is it possible to get 250hp out of a freshly built 3.2 with a turbo, how much boost would i have to run, and would there be any weak points? the engine does have forged pistons.

iron heads ?
what compression ratio ?
if not too high 10psi maybe max every day driving
maybe 15psi for a drag race with air water intercooler


head gaskets are allways a turbo weak point

exhaust valves are an other seals guides ect

with a good intercooler it should live IF the C/R is not too high and you use hi-test
use a water cooled turbo [yes plumbing is a pain ] but they help

just swap in a 3800....sorry

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Turbo 3800 E85 5spd spec5
11.53@126.7

quote Originally posted by drebinpk: is it possible to get 250hp out of a freshly built 3.2 with a turbo, how much boost would i have to run, and would there be any weak points? the engine does have forged pistons.

Possible? Yeah. (Thats about the best answer your going to get with the details you've listed)

We'd need more details than a 3.2 with forged pistons.

well theres really nothing more to tell about the engine it is completely a stock rebuild outside of the 3.1 crank and the forged pistons

what is a 3.2? .if you want an engine to last under boost you need bigger injectors , water meth injection , intercooling of your choice and a turbo that only puts out 6 psi .that being said 250 HP is pretty mild from 3.2 L .

quote Originally posted by drebinpk: is it possible to get 250hp out of a freshly built 3.2 with a turbo, how much boost would i have to run, and would there be any weak points? the engine does have forged pistons.

You have forged pistons and that's a great start. Boost pressure is resistance to air flow through an engine. Since you have a stock engine other than just a little increase in displacement and forged pistons 250 hp should not be a problem if you have the ability to tune it.

I'm going to assume your torque has increased most if you are using the Fiero upper intake. Your hp may not have increased much above stock using the 2.8 camshaft. So assuming you are starting with say 150 hp and stock to 9.5:1 compression you need an estimated 67% increase in power to get to 250 hp. which equates to a bout 10 psi: 14.7 psi x .67= 9.85psi. Theoretically ~14.7 psi of boost should double your hp, but since your engine is not 100% efficient, in a realistic setting it would take more than 14.7 psi to double power and more than 10 psi to increase it by 67%. If you're reaching 85% efficiency another 2 psi should get you there for a total of 12 psi.

That should be pretty close as the Turbo Grand Prix made about 225 hp with first design aluminum heads on about 8 psi with a restrictive turbo but better flowing intake than the Fiero.

I've been boosting Fieros since about 1995 and ran 12 psi on a bone stock 2.8L with an intercooler for a little while with nowhere near the tuning support available today. Later I settled for a daily 7-8 psi without an intercooler.
If tuned appropriately that engine will take 12 psi and more without any problem as long as you have a practical setup to facilitate boost, ~24 lb/hr injectors, manageable compression, at least a T3 turbo with .60 compressor and .81 turbine or something a little bigger but not much, intercooler or watermeth injection and a proper tune. There are members such as Darthfiero that can help you with tuning.

If you can get those things together you could possibly end up with more than 250 hp. You shouldn't need the following for that boost level but I would add head studs because they're cheap for the iron heads. The biggest challenge with your goal is posed by the intake system, the bottom end combo has been subjected to boost levels that high many times without problems on aluminum head motors which climb into the 300 hp range on less boost than that due to much better flow through the intake and heads. Having forged pistons adds considerable potential because most run stock with good success.

You will need to read a good bit for a good understanding of what it takes to succeed at this.

yes, it is most certainly possible
7730 ECM (or better), Cam ground for boost, some 24# injectors, knock sensor, strong ignition

the amount of boost needed depends much on the intake. well ported & something other than the Fiero intake will take ALOT less boost to make power.

If you are simply talking about a 2.8 with 3.1 crank and forged pistons, you will get about 210 BHP when you turbo it to 7 psi or so.

If you want more, you need more boost (10 psi is fine but beyond that is fairly pointless without an intercooler, and you should have knock sensing even at 10 psi).

You should also use a custom cam designed for turbo usage, and do all the usual things you would do on the intake and exhuast on an NA engine to increase flow. You don't need injectors as big as 24# necessarily - 19 - 22 can work just fine.

Turbo is a great way to force some power out of the cast iron heads, which are normally reluctant performers.

I've seen a dyno run with a 2.8 turbo'd getting close to that power on pump gas.

My Ferrari kit had a built 3.1 turbo. It was dynoed at the engine builder (Nascar shop) shop with the turbo at 8 pnds and put out over 275 on plain pump gas.

if you go with a different camshaft , make sure you get new GM lifters to go with it .and then find some dino oil with lots of zinc in it to make the new setup survive brake in .look up Joe Gibbs oil .

quote Originally posted by rogergarrison: My Ferrari kit had a built 3.1 turbo. It was dynoed at the engine builder (Nascar shop) shop with the turbo at 8 pnds and put out over 275 on plain pump gas.

Let me put on my hip boots......

ask if I care what you think...... That was now almost 10 years ago. A friend who built Nascar engines built the whole thing, Headwork, roller rockers and lifters, and tons of other tricks. Another friend is still using the same engine in his road race car. It also did 177 mph by GPS, 200 mph speedo and Sheriffs radar gun all at same time on a 10 mile stretch of Interstate. So you know where you can stick your boots. Oh, and it blew the doors off my buddies Shelby Mustang on top end. My 08 Bullit Mustang has hot cams and exhaust work and cant get within 30 mph of my old kit. My 413 Super Bee wont do 120 mph with 375 hp.

by the way, Design One Turbos claimed their bolt on Fiero kit made 250 hp according to sources, bolted on to bone stock 2.8s. I never seen anyone produce a dyno sheet to refute it.

[This message has been edited by rogergarrison (edited 02-12-2011).]

quote Originally posted by rogergarrison: by the way, Design One Turbos claimed their bolt on Fiero kit made 250 hp according to sources, bolted on to bone stock 2.8s. I never seen anyone produce a dyno sheet to refute it.

That is not correct.

Design One took over from the original turbo kit maker, Miller Woods, and they always stated that on a manual transmission car the output would be around 210 BHP as a bolt on kit on a stock 2.8 engine. Design One makes the claim for 200 BHP and does not specify what the stage 2 kits with higher boost and knock sensor produces. Simply take a look at http://www.design1systems.com/turbo/index.html to confirm.

I installed my Miller Woods kit in 1991 and have kept in touch with Kevin Leslie at Design One over the years. I also have all the original literature issued by both businesses. None ever claimed more than 210 BHP without higher boost and internal modification.

Ill stand corrected on that Bill. Id always heard 250 was the claim, but I never intended it for a stock 2.8 so didnt do much digging. I drove the car for 100,000 miles, but detuned it down to 4 pnds of boost shortly after it was installed for longer life since it was my only car at the time. I still stand on my dyno figs for my motor though since it was in black and white from a very reputable race shop ran by my friend. The speed is not in doubt...I drove the car.

quote Originally posted by rogergarrison: My Ferrari kit had a built 3.1 turbo. It was dynoed at the engine builder (Nascar shop) shop with the turbo at 8 pnds and put out over 275 on plain pump gas.

Had? Did you sell it?

quote Originally posted by drebinpk: well theres really nothing more to tell about the engine it is completely a stock rebuild outside of the 3.1 crank and the forged pistons

Is it just me, or doesn't a 2.8L with a stock rebuild and a 3.1 crank make something closer to a 2.9L and not a 3.2L?

If you want to make some decent power over just turbocharging basically a stock motor, these guys have been giving some good advice. You don't NEED an intercooler or any kind of chemical injection. Your ECM should be able to compensate for a few pounds of boost already.

If you want to make more use of the boost, it would be best to get some higher flow injectors (because your stock ones will max out), A new cam (to increase valve duration), and just make it generally breath better ( Port the exhaust or get headers, Open up the intake a bit, or buy a hi-flow one).

You'll also have to figure out what size of turbocharger your going to want. A larger turbocharger won't make as much power down low in the power band, but will make alot more higher... Where a small turbo will spool quick with only minimum lag.. Or a mid-range turbocharger...

It really boils down to how much money you want to spend and whose doing the work. If your piecing it together with junkyard parts, make sure you do your research.

quote Originally posted by Custom2M4: Is it just me, or doesn't a 2.8L with a stock rebuild and a 3.1 crank make something closer to a 2.9L and not a 3.2L?

It makes a 3.1, since the 2.8 and 3.1 have the same bore. With a .030 overbore it makes a 3.2.

quote Originally posted by rogergarrison: ask if I care what you think...... That was now almost 10 years ago. A friend who built Nascar engines built the whole thing, Headwork, roller rockers and lifters, and tons of other tricks. Another friend is still using the same engine in his road race car. It also did 177 mph by GPS, 200 mph speedo and Sheriffs radar gun all at same time on a 10 mile stretch of Interstate. So you know where you can stick your boots. Oh, and it blew the doors off my buddies Shelby Mustang on top end. My 08 Bullit Mustang has hot cams and exhaust work and cant get within 30 mph of my old kit. My 413 Super Bee wont do 120 mph with 375 hp. by the way, Design One Turbos claimed their bolt on Fiero kit made 250 hp according to sources, bolted on to bone stock 2.8s. I never seen anyone produce a dyno sheet to refute it.

LOL.

I did a turbo on a 3.1 and 3.4. I ran around 8psi, and they are nothing to laugh at. I have 3800 SC, and though it is more powerful, certainly more torque, it is not much more of a contender than the 60 degree engines. I estimate I was making close to 200hp. The thing about those turbo engines is they make a lot of heat, with the turbo under the hood and the turbo manifold you will see the increase in heat. Be smart and make sure you put the air filter outside the engine compartment.

[This message has been edited by RotrexFiero (edited 02-13-2011).]

Well...

My 3.1L engine orbited Mercury. I was only commanding 2 lbs of boost. The engine was built by Chuck Norris.

This kind of hearsay is what puts the community as a whole in metaphorical "reverse". It's not really about who's opinion matters, it's about context and the empirical data which qualifies what's being claimed. An iron head 60* making 275bhp on 8 lbs of boost, this is pretty outlandish. Is there any science behind it, a dynometer sheet perhaps?

quote Originally posted by rogergarrison: My Ferrari kit had a built 3.1 turbo. It was dynoed at the engine builder (Nascar shop) shop with the turbo at 8 pnds and put out over 275 on plain pump gas.

The "shop" was blowing smoke up your ass.

Dyno sheet or it never happened.

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Buy a fiero, become a mechanic
3.4 dohc Install
Sub Install
Northstar Install

quote Originally posted by L67: Well... My 3.1L engine orbited Mercury. I was only commanding 2 lbs of boost. The engine was built by Chuck Norris. This kind of hearsay is what puts the community as a whole in metaphorical "reverse". It's not really about who's opinion matters, it's about context and the empirical data which qualifies what's being claimed. An iron head 60* making 275bhp on 8 lbs of boost, this is pretty outlandish. Is there any science behind it, a dynometer sheet perhaps?

But even GM claimed 275hp with Falconer ported heads out of a 2.8...
I have a dyno of my 3.4 making 249 ft*lbs of torque naturally aspirated... Why is it so hard to believe from a boosted 3.2?

oops, mixed up two threads
(We all already knew that garrison made 2,531hp on watered down 87 octane on his NASCAR built engine that god himself couldn't prefect)

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Turbo 3800 E85 5spd spec5
11.53@126.7

[This message has been edited by Justinbart (edited 02-13-2011).]

This could easley be done with the 3400 SFI out of a Grand am. I have yet to get mine dynoed but the P/O said its getting about 240-250 or so to the wheels.

[This message has been edited by pontiackid86 (edited 02-13-2011).]

quote Originally posted by lou_dias: Why is it so hard to believe from a boosted 3.2?

“The deepest sin of the human mind is to believe things without evidence” -Thomas Huxley (1825-1895)

Where's the dyno sheet lou?

quote Originally posted by lou_dias: But even GM claimed 275hp with Falconer ported heads out of a 2.8... I have a dyno of my 3.4 making 249 ft*lbs of torque naturally aspirated... Why is it so hard to believe from a boosted 3.2?

Yeah, Falconer got that much power out of a 2.8, but that was on a PURE RACE engine with a throttle per cylinder intake manifold and long tube headers, as well as a LOT of port work (I have a pallet of heads they ported), HUGE cams, titanium valves, compression and built rotating assembly, etc.

250 to 275 HP out of an iron head 3.1 is perfectly believable, but will require boost pressures between 15 and 20 psi and good efficient turbo selection (IE, a T3 stands exactly zero chance of getting there).

Getting to 177 MPH on a vehicle turbocharged by a T3 only happens if that vehicle's a motorcycle.

quote Originally posted by L67: “The deepest sin of the human mind is to believe things without evidence” -Thomas Huxley (1825-1895) Where's the dyno sheet lou?

I think it's reasonable to believe reasonable things consistent with experience without evidence.
If I called you up before you got out of bed and said "the sky is blue today", you'd probably believe me. If I said "the sky is orange today", you probably would not believe me, even if you hadn't been outside to see the sky yourself yet.

That's why classic BS'ers fail... they claim things that aren't reasonable.

[This message has been edited by Will (edited 02-14-2011).]

quote Originally posted by lou_dias: But even GM claimed 275hp with Falconer ported heads out of a 2.8... I have a dyno of my 3.4 making 249 ft*lbs of torque naturally aspirated... Why is it so hard to believe from a boosted 3.2?

If my observations over the years serve me correctly, it is much easier to achieve low hp and high torque on a low flowing motor than it is to have high hp on the same engine. I don't recall your numbers exactly but in your case the hp numbers are relatively low for your efforts. You need flow to get high hp numbers as they generally occur at higher rpm than torque peak. I wonder if any of the high hp numbers being alluded to on 2.8 heads involved a carbed intake system.

quote Originally posted by L67:“The deepest sin of the human mind is to believe things without evidence” -Thomas Huxley (1825-1895)

That's an interesting quote given its mention of sin (regarding its origin) and the failure to recognize belief without evidence, as an act of faith.

quote Originally posted by Will: 250 to 275 HP out of an iron head 3.1 is perfectly believable, but will require boost pressures between 15 and 20 psi and good efficient turbo selection (IE, a T3 stands exactly zero chance of getting there). That's why classic BS'ers fail... they claim things that aren't reasonable.

Exactly!

Steve Hamm and Shaun Hammitt are both great people to talk to about what the iron head motors can do when putting large amounts (15+ lbs) of boost through said engine. Making 275 wheel horsepower (or crank even) on 8lbs of boost far fetched, given how inefficient the engine is in stock form. Where's the data?

quote Originally posted by Joseph Upson: That's an interesting quote given its mention of sin and the failure to recognize belief without evidence, as an act of faith.

Thomas Huxley was of course an athiest. Clinical psychology only concretes what he said. Whenever I go to local Fiero gatherings, I usually stay pretty quiet and size everyone up in the room on how they carry themselves and the things they say. In a room of 20 people, my experience has been only two or three (10%) know what they're talking about and the rest "believe" many things. Automotive enthusiast are on a whole are very idiosyncratic by nature. Science is a great tool in weeding out all the nonsense. I see very little of it here.

[This message has been edited by L67 (edited 02-14-2011).]

I have no problem believing 270+ horsepower from a 3.1 Turbo.

If you spend enough money, you can pretty much get any engine to do anything...

All that's needed is a good turbo, forged rods (as I understand it, people have been able to adapt SBC rods to the V6/60), forged pistons (which are available) the right compression ratio, tuning, etc...

EDIT: That Design-1 system looks REALLY decent. I even like the exhaust system...

I wonder what effect that will have on the trunk in terms of heat? Anyone here have that kit?


~$4,000 is hard to swallow for basically an extra 50hp... but... if I want to keep my pretty intake, and still play with the big dogs... it might be my only option...


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Todd,
2008 Jeep Patriot Limited 4x2
2002 Ford Explorer Sport 2dr 4x2
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6
1973 Volkswagen Type-2 Transporter

[This message has been edited by 82-T/A [At Work] (edited 02-14-2011).]

quote Originally posted by 82-T/A [At Work]: If you spend enough money, you can pretty much get any engine to do anything...

And that's how I orbited Mercury.

quote Originally posted by 82-T/A [At Work]: I have no problem believing 270+ horsepower from a 3.1 Turbo. If you spend enough money, you can pretty much get any engine to do anything... All that's needed is a good turbo, forged rods (as I understand it, people have been able to adapt SBC rods to the V6/60), forged pistons (which are available) the right compression ratio, tuning, etc...

The two most important things are boost pressure and turbo efficiency. A "good" turbo is one that's efficient (>75%) at 15-20 psi of boost with enough airflow for 300 HP. This DOES *NOT* describe the Design1 turbo.

[This message has been edited by Will (edited 02-14-2011).]

quote Originally posted by L67: “The deepest sin of the human mind is to believe things without evidence” -Thomas Huxley (1825-1895) Where's the dyno sheet lou?

https://www.fiero.nl/forum/F...2/HTML/075502-3.html

No point speculating. A dyno sheet is the only thing people believe nowadays. Unless you can provide one, or you are claiming stock engine specs then there is no need to list your HP level. Period.