Tuning the ecoboost

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1955moose

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To say 40 horsepower can't be felt, is nuts. You can actually feel an acceleration difference with as little as 10 horsepower. Not only does the [emoji470] give a seat of the pants difference, the additional torque that most always comes with it is what you "feel" on the lower end of RPM range 1k to 3.5k. if you don't believe it, drive a 99-04 2 valver, then jump into an 05-06 3valve. If you don't notice a difference 40 horsepower makes, then that individual is numb, and has no right driving either of them. That individual should be pushing a skateboard like they do here in the Haight Ashbury of my lovely fog City. Just don't complain when one of those "slow" expeditions passes you!

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rjdelp7

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To say 40 horsepower can't be felt, is nuts. You can actually feel an acceleration difference with as little as 10 horsepower. Not only does the [emoji470] give a seat of the pants difference, the additional torque that most always comes with it is what you "feel" on the lower end of RPM range 1k to 3.5k. if you don't believe it, drive a 99-04 2 valver, then jump into an 05-06 3valve. If you don't notice a difference 40 horsepower makes, then that individual is numb, and has no right driving either of them. That individual should be pushing a skateboard like they do here in the Haight Ashbury of my lovely fog City. Just don't complain when one of those "slow" expeditions passes you!

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I have driven a 06, 12 and 15. They wouldn't exactly 'blow the doors off' my 1st Gen. They can definitely tow better and more. None were that impressive, but get the job done fine. My point was the price($400) doesn't justify the 40hp. The poster wanted honest feedback, not stats, graphs and charts. I don't race my Expedition. I can't understand, why someone would buy one and expect high performance. The put the V6 in it to save gas for soccer Moms.
 

1955moose

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$400.00 for horsepower bumps these days is cheap. You can spend that much on an air filter, and a couple of mufflers. This rant has gotten a little out of control. You, like me, have been on the forum a long time. Let it go. Theirs always something each week or so. We'll move along to another problem, another day.

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TobyU

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As far as towing and feeling a hp difference. We must remember that the shift points and feel of power is very different and a turbo charged car is even more noticeable.
It is very possible for tow cars with identical peak HP on a dyno for one to feel a lot faster than the other.
It is also common with turbo cars for two to have the exact eta in 1/4 mile but one have a lot more power and acceleration in one part of the race.

A tune takes advantage of all the computer abilities to alter many things.
An old car in the 70's the only "computer" style or electronic things you could do to tune it would be initial timing and timing advance and or mechanical advance.
For real power increases or any more than that it took mechanical things.
Even adjusting secondary carb plates and top air horn flaps did a a lot but was a mechanical change. Then you has the more air in more air out idea with carbs intakes headers more open exhaust. Then you had cams (timing and flow) heads (flow).

You can feel a difference and see it in the 1/4 mile times of about any newer vehicle after it is tuned by electronic means. You can really get a lot from any forced induction car. Hard to find a car that the turbo or blower where engine is using its max cfm or pressure at all times.
Electronically you can crank the boost up and if you can increase the duty cycle of the injectors you can crank fuel up and get a lot of hp. Then if you can go a lot more on injectors you can add e85 and get more boost with no detonation.

In the early days of turbo Grand Nationals we could get over a second 1/4 mile et reduction from a 1.29 little threaded turnbuckle at hardware store, a paperclip, and higher octane fuel.
Then if you wanted more, you got adjustable fuel pressure regulator and an eprom chip to fire injectors more. Then after you maxed that out you had to go bigger injectors and other chips. Then eventually after you were a lot faster than stock you would need to get a bigger turbo (downpipe was always first).
Most vehicles have some room for increased performance with all or most factory parts. Some have a LOT.
With the the 3.8 Buick they were running low to mid tens with factory heads and original factory exhaust manifolds which were like shorty headers, factory intake, TB, factory 3.42 rear axle etc.

These ecoboost turbos should have a lot of potential in them.
 

Mike Wolfe

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As far as towing and feeling a hp difference. We must remember that the shift points and feel of power is very different and a turbo charged car is even more noticeable.
It is very possible for tow cars with identical peak HP on a dyno for one to feel a lot faster than the other.
It is also common with turbo cars for two to have the exact eta in 1/4 mile but one have a lot more power and acceleration in one part of the race.

A tune takes advantage of all the computer abilities to alter many things.
An old car in the 70's the only "computer" style or electronic things you could do to tune it would be initial timing and timing advance and or mechanical advance.
For real power increases or any more than that it took mechanical things.
Even adjusting secondary carb plates and top air horn flaps did a a lot but was a mechanical change. Then you has the more air in more air out idea with carbs intakes headers more open exhaust. Then you had cams (timing and flow) heads (flow).

You can feel a difference and see it in the 1/4 mile times of about any newer vehicle after it is tuned by electronic means. You can really get a lot from any forced induction car. Hard to find a car that the turbo or blower where engine is using its max cfm or pressure at all times.
Electronically you can crank the boost up and if you can increase the duty cycle of the injectors you can crank fuel up and get a lot of hp. Then if you can go a lot more on injectors you can add e85 and get more boost with no detonation.

In the early days of turbo Grand Nationals we could get over a second 1/4 mile et reduction from a 1.29 little threaded turnbuckle at hardware store, a paperclip, and higher octane fuel.
Then if you wanted more, you got adjustable fuel pressure regulator and an eprom chip to fire injectors more. Then after you maxed that out you had to go bigger injectors and other chips. Then eventually after you were a lot faster than stock you would need to get a bigger turbo (downpipe was always first).
Most vehicles have some room for increased performance with all or most factory parts. Some have a LOT.
With the the 3.8 Buick they were running low to mid tens with factory heads and original factory exhaust manifolds which were like shorty headers, factory intake, TB, factory 3.42 rear axle etc.

These ecoboost turbos should have a lot of potential in them.

Sure do have a lot of potential
The gen II engines have both port & GDI injectors have high enough flow rate to accommodate up to 50% ethanol
That along with 91 octane premium will boost toe octane level to well over 100
Can get close to 600hp with the ECOBOOST with a E50 blend:burnout:
 

Garrett

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Only drove about 15 miles in city traffic today after loading my perf/tow tune. I'll admit I'm a total n00b and don't know the first thing about engines, etc., but the punch was very noticeable! I also felt like the shifting was much better and still buttery smooth.

Do you lose the gear indicator next to the RPM gauge when you have a tune loaded, or did I accidentally turn it off?
 

Mike Wolfe

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Only drove about 15 miles in city traffic today after loading my perf/tow tune. I'll admit I'm a total n00b and don't know the first thing about engines, etc., but the punch was very noticeable! I also felt like the shifting was much better and still buttery smooth.

Do you lose the gear indicator next to the RPM gauge when you have a tune loaded, or did I accidentally turn it off?
touch the + of the manual shift buttons & it will show up again
 

TobyU

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Sure do have a lot of potential
The gen II engines have both port & GDI injectors have high enough flow rate to accommodate up to 50% ethanol
That along with 91 octane premium will boost toe octane level to well over 100
Can get close to 600hp with the ECOBOOST with a E50 blend:burnout:


You got to love it when they make something with a lot of headroom to tweak. I just would have not put it in a truck and suv body. But that's just me.

Now when they give you a forged steel crank and a special stronger steel block to go with it like on the turbo regals...it's just heaven.

Some of these motor divisions know a lot more than they let on.
The turbo regals in 1986 had a dash light for PWR INJ....It was never used. But more than likely they were thinking about water or alcohol injection which was all the rave just a few years ago in them. Now people just mix E-85 and adjust fuel volume and crank up the boost.
I still like the idea of having a 7th injector of alcohol under boost.

Few people in 84-87 had any idea what knock counts, timing retard, etc was but it's all there in a pre OBDII ALDL connector.
The whole fuel thing is mapped into little blocks....It's crazy? Especially for mod 80s.

They knew exactly what they were doing.
They only let them tweak the GNX a little (1 sec). If they would have let the Buick team go full out they would have had 1000hp+ 3.8s ( that's only 231cu in). Wicked!!!
 

Mike Wolfe

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You got to love it when they make something with a lot of headroom to tweak. I just would have not put it in a truck and suv body. But that's just me.

Now when they give you a forged steel crank and a special stronger steel block to go with it like on the turbo regals...it's just heaven.

Some of these motor divisions know a lot more than they let on.
The turbo regals in 1986 had a dash light for PWR INJ....It was never used. But more than likely they were thinking about water or alcohol injection which was all the rave just a few years ago in them. Now people just mix E-85 and adjust fuel volume and crank up the boost.
I still like the idea of having a 7th injector of alcohol under boost.

Few people in 84-87 had any idea what knock counts, timing retard, etc was but it's all there in a pre OBDII ALDL connector.
The whole fuel thing is mapped into little blocks....It's crazy? Especially for mod 80s.

They knew exactly what they were doing.
They only let them tweak the GNX a little (1 sec). If they would have let the Buick team go full out they would have had 1000hp+ 3.8s ( that's only 231cu in). Wicked!!!

At that time we worked with LUCAS & developed high flow disc style injectors for the Grand nationals
sold a bunch of them in the 80's & early 90's
 

rjdelp7

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You got to love it when they make something with a lot of headroom to tweak. I just would have not put it in a truck and suv body. But that's just me.

Now when they give you a forged steel crank and a special stronger steel block to go with it like on the turbo regals...it's just heaven.

Some of these motor divisions know a lot more than they let on.
The turbo regals in 1986 had a dash light for PWR INJ....It was never used. But more than likely they were thinking about water or alcohol injection which was all the rave just a few years ago in them. Now people just mix E-85 and adjust fuel volume and crank up the boost.
I still like the idea of having a 7th injector of alcohol under boost.

Few people in 84-87 had any idea what knock counts, timing retard, etc was but it's all there in a pre OBDII ALDL connector.
The whole fuel thing is mapped into little blocks....It's crazy? Especially for mod 80s.

They knew exactly what they were doing.
They only let them tweak the GNX a little (1 sec). If they would have let the Buick team go full out they would have had 1000hp+ 3.8s ( that's only 231cu in). Wicked!!!
The Buick GN was junk. $30K, back in 1987. Cheap plastic interior, cloth seats, crappy black paint and steel wheels. The heavy "G' body was a lousy platform. The tri-angulated 4 link rear end, was a disaster. It caused a twist in the chassis and could not get traction or launch straight(G body shuffle). The 1987 GNX added ladder bars, but it still sucked. The under rated, 225hp early 90's V8, $16K Mustang GT's could beat them or easily keep up. The one guy I knew, that owned a GN, blew the motor(head gaskets, aka too much boost). He added NOS to the new motor and soon melted the pistons. Wicked?
 
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edizzle

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The Buick GN was junk. $30K, back in 1987. Cheap plastic interior, cloth seats, crappy black paint and steel wheels. The heavy "G' body was a lousy platform. The tri-anglaited 4 link rear end, was a disaster. It caused a twist in the chassis and could not get traction or launch straight(G body shuffle). The 1987 GNX added ladder bars, but it still sucked. The under rated, 225hp early 90's V8, $16K Mustang GT's could beat them or easily keep up. The one guy I knew, that owned a GN, blew the motor(head gaskets, aka too much boost). He added NOS to the new motor and soon melted the pistons. Wicked?
LOL!!!
 

TobyU

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The Buick GN was junk. $30K, back in 1987. Cheap plastic interior, cloth seats, crappy black paint and steel wheels. The heavy "G' body was a lousy platform. The tri-angulated 4 link rear end, was a disaster. It caused a twist in the chassis and could not get traction or launch straight(G body shuffle). The 1987 GNX added ladder bars, but it still sucked. The under rated, 225hp early 90's V8, $16K Mustang GT's could beat them or easily keep up. The one guy I knew, that owned a GN, blew the motor(head gaskets, aka too much boost). He added NOS to the new motor and soon melted the pistons. Wicked?

As with some other posts where you come across arrogant and condescending, but the worst part is you spout non factual information. You do have a few correct facts thrown in there. But not many.
I'll stay away from subjective personal preference words like wicked and you can stay away from one's like junk. As those are opinions and not fact.

The Buick Grand National or GN as commonly referred to was not $30,000. They were sitting in the dealers at $17,804. The actual MSRP was right at 16,xxxbut by the time you saw them sitting there with the window sticker on them they were right around $17,000.
So there is correct fact number one.

Maybe you mixed that up with the GNX that you mentioned later. Those were 26,000 - 28,0000 with most people paying 28,000 unless they were a GM employee. Of course that's only if they ordered them early before the word got out what they were and the dealers started charging more for them.
That's fact number two.

Grand Nationals did not have a triangulated 4-link suspension.
GNs had the same plain old solid rear axle that every basically every other G body (you got G body right) had.

The GNX add a longitudinal torque bar coming across the back of the vehicle, a special differential cover with mounting points on it and a panhard bar.
This changed the traditional rear wheel drive car squatting action under torque to a rear-end raising up and getting excellent traction under torque.

This suspension tutorial would be fact number three.

Paint was black, you got that right too. It was lacquer and they did have some problems with cracking. You almost got the wheels right. 86 and 87 were steel wheels with turbo six centers. 84 and 85 were aluminum wheels but nobody really wants those.

As a side note, who am I kidding here. Do you even know the difference between 84-85 and 86-87? Go ahead, I'll wait while you Google it.

They were rated at 225 horsepower by some so you got that one right too although those were joke ratings and hardly anybody stayed at 225 very long. Actually I think the production specs were 245 for 87 and 276 for the GNX.
However in the very next sentence you said a Mustang GT could beat them. That's the biggest joke of all time.
There is no stock Mustang GT EVER not even after you blow up the crummy transmission and then the second Borg Warner T5 transmission and then put a Tremec in it.... can ever beat a stock 86 to 87 Grand National.
Once again, maybe your experiences with an 84-85 but for most of us those don't really count.

That's a big fact number four.

Head gaskets did blow on Grand Nationals dr. When you over boosted them. They were intentionally designed this way with only 2 fewer head bolts.
The engineers designed it this way to be the weak link so you wouldn't just keep building boost and pressure and snap the crankshaft in half or crack or flex the block.
The people that blew head gaskets were the people that started modifying things but didn't know what they were doing and modifying the wrong way.

Very, very few if any people added NOS to Grand Nationals.
It would be an absolute waste and a joke. Why pay even back in the day $45 for a minute and a half of juice boost when you have unlimited amount and time of boost already under the hood.
Grand Nationals an NOS was never a thing.

That would be fact number five for you.

I am an opinionated sob and will tell you when something is my personal opinion for whatever reasons or if I have no reasons but.....
I can damn well guarantee you that if I say something is true or a fact, you can take that shit to the bank.

Back in the day when these cars were new and running the streets, I chased down and raced them and the Mustangs. I hated the 5. 0 Mustang, mostly their owners, with a passion.
I have lost count of how many times I have done a smoking U-turn through four lanes of traffic to go chase down a Mustang whose car look like he thought he was bad.
They were far fewer Grand Nationals on the road but I chase them too.
I was an equal-opportunity offender. Every time we would get next to a Grand National we would roll down the window and point at the emblem on the side of it and when we had their attention we would say... "I don't see anything Grand about it"
Then we would dust them. The owner is always wanted to race from a 20-25 mph roll because that was their peak. They had a lot less off the line..
That was totally fine with me. I was running a highly built car on the street and had no problems dusting them no matter how they wanted to run.

So enough adjacent topics of my stories but if you're going to spew things as fact, get your facts straight.

I won't go out around quoting how many 92 Cobra Mustangs they made because I frankly don't know. I just know some of them had a little snake on the side and they were rated at like 10 more horsepower.

The beauty of the Grand National and any other 86 and 87 Turbo Regal for that matter and for the 89 turbo Trans Am, was that it was probably the easiest and cheapest car out there to modify to get substantial power and quarter mile ETA games.
At that time you could go out and get a chip for a Camaro or a Mustang and some did little to nothing but you had to start swapping a lot of hard parts to get any performance gains. The Grand National already had so much headroom built into it all you had to do was access that hidden power and you could go quite far.
 
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rjdelp7

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As with some other posts where you come across arrogant and condescending, but the worst part is you spout non factual information. You do have a few correct facts thrown in there. But not many.
I'll stay away from subjective personal preference words like wicked and you can stay away from one's like junk. As those are opinions and not fact.

The Buick Grand National or GN as commonly referred to was not $30,000. They were sitting in the dealers at $17,804. The actual MSRP was right at 16,xxxbut by the time you saw them sitting there with the window sticker on them they were right around $17,000.
So there is correct fact number one.

Maybe you mixed that up with the GNX that you mentioned later. Those were 26,000 - 28,0000 with most people paying 28,000 unless they were a GM employee. Of course that's only if they ordered them early before the word got out what they were and the dealers started charging more for them.
That's fact number two.

Grand Nationals did not have a triangulated 4-link suspension.
GNs had the same plain old solid rear axle that every basically every other G body (you got G body right) had.

The GNX add a longitudinal torque bar coming across the back of the vehicle, a special differential cover with mounting points on it and a panhard bar.
This changed the traditional rear wheel drive car squatting action under torque to a rear-end raising up and getting excellent traction under torque.

This suspension tutorial would be fact number three.

Paint was black, you got that right too. It was lacquer and they did have some problems with cracking. You almost got the wheels right. 86 and 87 were steel wheels with turbo six centers. 84 and 85 were aluminum wheels but nobody really wants those.

As a side note, who am I kidding here. Do you even know the difference between 84-85 and 86-87? Go ahead, I'll wait while you Google it.

They were rated at 225 horsepower so you got that one right too although those were joke ratings and hardly anybody stayed at 225 very long.
However in the very next sentence you said a Mustang GT could beat them. That's the biggest joke of all time.
There is no stock Mustang GT EVER not even after you blow up the crummy transmission and then the second Borg Warner T5 transmission and then put a Tremec in it.... can ever beat a stock 86 to 87 Grand National.
Once again, maybe your experiences with an 84-85 but for most of us those don't really count.

That's a big fact number four.

Head gaskets did blow on Grand Nationals dr. When you over boosted them. They were intentionally designed this way with only 2 fewer head bolts.
The engineers designed it this way to be the weak link so you wouldn't just keep building boost and pressure and snap the crankshaft in half or crack or flex the block.
The people that blew head gaskets were the people that started modifying things but didn't know what they were doing and modifying the wrong way.

Very, very few if any people added NOS to Grand Nationals.
It would be an absolute waste and a joke. Why pay even back in the day $45 for a minute and a half of juice boost when you have unlimited amount and time of boost already under the hood.
Grand Nationals an NOS was never a thing.

That would be fact number five for you.

I am an opinionated sob and will tell you when something is my personal opinion for whatever reasons or if I have no reasons but.....
I can damn well guarantee you that if I say something is true or a fact, you can take that shit to the bank.

Back in the day when these cars were new and running the streets, I chased down and raced them and the Mustangs. I hated the 5. 0 Mustang, mostly their owners, with a passion.
I have lost count of how many times I have done a smoking U-turn through four lanes of traffic to go chase down a Mustang whose car look like he thought he was bad.
They were far fewer Grand Nationals on the road but I chase them too.
I was an equal-opportunity offender. Every time we would get next to a Grand National we would roll down the window and point at the emblem on the side of it and when we had their attention we would say... "I don't see anything Grand about it"
Then we would dust them. The owner is always wanted to race from a 20-25 mph roll because that was their peak. They had a lot less off the line..
That was totally fine with me. I was running a highly built car on the street and had no problems dusting them no matter how they wanted to run.

So enough adjacent topics of my stories but if you're going to spew things as fact, get your facts straight.

I won't go out around quoting how many 92 Cobra Mustangs they made because I frankly don't know. I just know some of them had a little snake on the side and they were rated at like 10 more horsepower.

The beauty of the Grand National and any other 86 and 87 Turbo Regal for that matter and for the 89 turbo Trans Am, was that it was probably the easiest and cheapest car out there to modify to get substantial power and quarter mile ETA games.
At that time you could go out and get a chip for a Camaro or a Mustang and some did little to nothing but you had to start swapping a lot of hard parts to get any performance gains. The Grand National already had so much headroom built into it all you had to do was access that hidden power and you could go quite far.
Geez, That's a lot of info. Thanks for clearing up anything, I didn't have exactly right. 95% is still a 'A-', however. The Early 90's Mustang may of not of been the fastest, but who cares its 2019. I had a Ford mechanic tell me, they were actually 300+hp. Ford 'underrated' them after insurance companies, cried foul. I had fun with mine and easily beat a Monte SS and a Camaro. I tied a Vette and Buick GN. Jay Leno's Garage recently had a brand new GN, still sitting in the dealer. $29+ on the sticker. I do disagree, that Buick intentionally designed the head gaskets fail. If memory serves me, there is a safety or blow off valve. The one I drove, sounded like a fart(air release), every time you got off the gas, after being on boost. The Eco Boost should have a similar feature. That is a reason, I disagree they can be safely tuned for additional HP. The GN was a niche auto, with a strange mix old and new. It was quick(for the era), but 300hp in a heavy car, can only do so much. Many 'old school car guys', could not get past the turbo V6. The 1980's turbo attempts, did little to help its image. Compared to a similar Monte SS and its sad 305ci, The Buick GN was better. Yes, it was slightly and embarrassing, faster than the 87 Vette. The suspension, was designed for its smooth ride and increased interior space. It was a Buick, after all.
 
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TobyU

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Geez, That's a lot of info. Thanks for clearing up anything, I didn't have exactly right. 95% is still a 'A-', however. The Early 90's Mustang may of not of been the fastest, but who cares its 2019. I had a Ford mechanic tell me, they were actually 300+hp. Ford 'underrated' them after insurance companies, cried foul. I had fun with mine and easily beat a Monte SS and a Camaro. I tied a Vette and Buick GN. Jay Leno's Garage recently had a brand new GN, still sitting in the dealer. $29+ on the sticker. I do disagree, that Buick intentionally designed the head gaskets fail. If memory serves me, there is a safety or blow off valve. The one I drove, sounded like a fart(air release), every time you got off the gas, after being on boost. The Eco Boost should have a similar feature. That is a reason, I disagree they can be safely tuned for additional HP. The GN was a niche auto, with a strange mix old and new. It was quick(for the era), but 300hp in a heavy car, can only do so much. Many 'old school car guys', could not get past the turbo V6. The 1980's turbo attempts, did little to help its image. Compared to a similar Monte SS and its sad 305ci, The Buick GN was better. Yes, it was slightly and embarrassing, faster than the 87 Vette. The suspension, was designed for its smooth ride and increased interior space. It was a Buick, after all.


Buicks we're basically luxury cars. Lol
You can Google the MSRP for the Grand Nationals. They were in the 17.000s. The GNXs were the ones that were pushing 30k.

If you do some reading on it you'll also find the part about the head gaskets being design with the heads having red fewer bolts so they didn't want to put them down too tight to make it the part that would pop instead of blowing the whole engine.

Factory 3.8 turbo do not have a blow off valve. Blow-off valves are, often on turbo charged cars but not normally until a few years later and all of the import tuners. Some people have added them into the aftermarket turbo systems are intercoolers but the vast majority of 3.8 Buick turbo do not have a blow off valve. They only make a little bit of sound when you let off as the there air spools back through the air filter housing but it's definitely not the popping blow off farting sound that a blow off valve have. It's possible the one you had experience with had one added.

They are heavily modifiable and that's why it's hard to find one that's in Factory stock condition. Not that I would want to keep one in Factory stock condition because they were way too slow even though they were faster than the Corvettes of the same year. It's just that they are so easy to modify. There are tons horsepower to be had out of them.
All the horsepower is back then were underrated as they were net and they tried their best to get them low for numbers of years because of insurance purposes and everything else. The 5.0 and the GT Mustang was probably putting out around 295 to 315 horsepower that's if you had the engine out and put it on a dyno the real way you're supposed to test engines. The turbo 3.8s were also around that 300-320 mark.
Of all the turbo Buicks that have ever been in existence and are still in existence the vast majority of them are modified and a good deal faster than stock. It didn't take much at all to put these cars into the high 12 and that's something it took a lot more money to do with the normally aspirated cars like the Mustangs and the Corvettes at that time frame.
 

rjdelp7

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Buicks we're basically luxury cars. Lol
You can Google the MSRP for the Grand Nationals. They were in the 17.000s. The GNXs were the ones that were pushing 30k.

If you do some reading on it you'll also find the part about the head gaskets being design with the heads having red fewer bolts so they didn't want to put them down too tight to make it the part that would pop instead of blowing the whole engine.

Factory 3.8 turbo do not have a blow off valve. Blow-off valves are, often on turbo charged cars but not normally until a few years later and all of the import tuners. Some people have added them into the aftermarket turbo systems are intercoolers but the vast majority of 3.8 Buick turbo do not have a blow off valve. They only make a little bit of sound when you let off as the there air spools back through the air filter housing but it's definitely not the popping blow off farting sound that a blow off valve have. It's possible the one you had experience with had one added.

They are heavily modifiable and that's why it's hard to find one that's in Factory stock condition. Not that I would want to keep one in Factory stock condition because they were way too slow even though they were faster than the Corvettes of the same year. It's just that they are so easy to modify. There are tons horsepower to be had out of them.
All the horsepower is back then were underrated as they were net and they tried their best to get them low for numbers of years because of insurance purposes and everything else. The 5.0 and the GT Mustang was probably putting out around 295 to 315 horsepower that's if you had the engine out and put it on a dyno the real way you're supposed to test engines. The turbo 3.8s were also around that 300-320 mark.
Of all the turbo Buicks that have ever been in existence and are still in existence the vast majority of them are modified and a good deal faster than stock. It didn't take much at all to put these cars into the high 12 and that's something it took a lot more money to do with the normally aspirated cars like the Mustangs and the Corvettes at that time frame.
A guy I went High school with, who own one, claimed the 87 GNX was different. They were modified by and outside company. The early models were only like 200HP. Mustangs could beat them. The 87 GNX(experimental), maybe only 500 produced. They are the ones, people goes nuts for. Two were found untouched, in a dusty garage. They were on Ebay. Another 'new one' was just found in a shipping container. it went to a museum. Jay Leno offered 'sticker' to the dealer, for the one featured on his show. They wanted $200K. He joked, "you will have it, another 30 years at that price."
 

JExpedition07

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Well, as with most tuning threads.....here we are. We started on Earth and now we are over on Neptune.

Anyone ever tune their lawn mower? I’ve heard the Briggs and Stratton’s can make some serious gains with a 93 octane tune.
 
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TobyU

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A guy I went High school with, who own one, claimed the 87 GNX was different. They were modified by and outside company. The early models were only like 200HP. Mustangs could beat them. The 87 GNX(experimental), maybe only 500 produced. They are the ones, people goes nuts for. Two were found untouched, in a dusty garage. They were on Ebay. Another 'new one' was just found in a shipping container. it went to a museum. Jay Leno offered 'sticker' to the dealer, for the one featured on his show. They wanted $200K. He joked, "you will have it, another 30 years at that price."

The GNX was different. Stood for Grand National Xperimental but I've also seen it Xtreme. They were a second faster in 1/4 mile. ASC McLaren made them. Random 87 GNs were sent there. 547 were produced. Each had number 1 -547 (have to read the history I think 1 and 2 were never sold and one was stolen and wrecked or something)
Each had number plate on dash and numbered owner's manual. Numbers on intercooler too.

The early GNs were 84 -85. Called Hot Air cars because no intercooler. Less hp and slower and you are right about the Mustangs. Ran right about with them stock for stock but a good power shifting driver could take one...but a good turbo spooling launcher in GN could take the Mustang.
86-87 were intercooled cars. More hp and faster. About 1-1.5 seconds faster than Mustangs.

All GNXs were 87.
GNXs had several upgrades. Suspension, rear seat braces, front braces too IIRC, custom Stuart Warner dash and gauges, ceramic turbine in turbo (spools faster I guess), better intercooler (neck design I think), ecm eprom chip tweaks I think too, and some more I can't remember now.
They could have been a lot faster than they were but that was a time when hp and fast cars were out of style. They guys at Buick were on their game! Would have been amazing to see them go full tilt.

Most every GN out there is faster than a stock GNX. You can't touch or alter a GNX because they are worth so much. I guess some people keep everything and put them back to original but like with most high dollar collectables- you can''t have any fun or you kill the value.
So, there are tons of regular GNs and T-type regals with plush soft interiors like a lesabre inside that are screaming machines.

Eastern Performance had customers back in 92 running 10.20 -10.70s with stock blocks and non tubbed rear ends.
This being a big heavy car with only 6 cyls. They chevelles and novas etc with 454s and bigger had a hard time doing this unless you tubbed the rear and put some serious meat on the back.
Back then I think the world'd fasted turbo buick was 8.46 1/4 mile. Kenny Duttweiler was the man back then. I think the fasted GN now is 7.29 or so. Heck maybe they have cracked into the 6s.
 
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TobyU

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I love this guy but they got the editing wrong in one part.
He says that Buick took off the season for 83 and came back with better..They did but it shows an 86 or 87 intercooled engine in the pic after he says it.
the 84 and 85 were better but the turbo was not up front at all. It was around back between firewall and engine and lower.

Available in any color you want...as long as that's black!!!! LOL
That's a better line than I am your father...

I have to say....even with my fairly extensive GN and GNX interests...I had NEVER seen this video.

IT'S the best EVER.
He rocks!!!

I have always agreed with him on bringing it back.
They would just screw it up.
Maybe if they would follow the Hellcat and Demons lead with the retro style (compare a 70 challenger to a new one outside)
I mean if they make it smaller or change one look on the outside they would destroy it.
They were already fast and with mods really fast. I new one with a V6 -required- with 800hp dusting a Challenger would be fun.

They already made "The baddest car to ever eat up American pavement" clapped their hands as he said and said "See ya". Ended on the highest note ever.
1987 12.7s BABY!! Although with stock GNX tolerances like exact wastegate rod length adn gas etc...the turbo cars varied more than N/A cars in 1/4 miles. Most GNXs ran 13.0s to 13.2s but a few screamed...maybe hotter stickier pavement that day.
Either way WICKED!!!! There is no better word to describe them.
 
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