ok i am new i was wondering if any one has attempted to do this if u have or know any that has could some one direct me in the right way

It's not worth it. The Dukes tend to explode.

Nate

------------------

My Web page

i know that but i just wanna know if any one has done that

Sure! Pontiac did, and it exploded. Simple as that.

Some people on the Forum have turbocharged the Duke. Look for one by Oslo a while back, and there was another I can't offhand remember the name of right now. Although the Dukes don't literally "explode" they are relatively fragile motors that don't hold up well to large amounts of horsepower. Between cracking blocks and heads, weak cranks, and generally poor performance of the cylinder head porting it is hard to get much more than 100-120 reliable horsepower out of one.

It would be possible with a great amount of work to go past that, but it would have to be to prove a point because it is much easier and cheaper to swap in a much more robust motor like the 3800SC or Caddy 4.9, or even any of the small block options using a V8 Archie kit.

JazzMan

i only wanna run about 6 lbs of boost i just want the sound, plus the new engine is out of other gm tech4

[This message has been edited by sergioazevedo (edited 06-10-2004).]

quote Originally posted by FastIndyFiero: It's not worth it. The Dukes tend to explode. Nate

Hey Nate I saw your webpage and your sig and you claim your duke is handling 180 to 200 hp. What did you do to make the block handle all that? What would be the difference in slapping a turbo on a stock rebuilt motor and getting less hp vs. what you did to yours?

Not trying to doubt you or put you on the spot. Its just that you seem to have good experience with this engine.

------------------
I have the precious gift of patience.....it just takes too long to use it!

The first 2 pictures are of his Super Duty block and crank, the SD rods are mentioned in the caption.

GL

[This message has been edited by Tugboat (edited 06-10-2004).]

I have yet to see a cracked Iron Duke block (that wasn't cracked as a result of something else failing first). The stock reciprocating parts seem to be pretty worthless though (rods, pistons, crank) with few workarounds (SD crank/Mercruiser crank, custom rods, aftermarket pistons) I also hold out hope for a robust duke one day.

Kurt

I have had 2 turbo'ed duke fieros. Neither exploded but WTF do I know?

------------------
'02 Subaru WRX, 5MT, Loaded, "free mods", Green induction, Vishnu silicone hoses & ECM, Gutted up-pipe, Halman ES MBC @ 15.5psi, JDM STi guage cluster, EGT/02 fix.
'88 Fiero Formula 5-speed, Loaded, Sunroof, YELLOW! EBC Green stuff pads, Poly everything, Bridgestone Potenza RE930's, K&N, Sprint headers, Cat elim, T/B coolant elim, Dickman UGSK w/ comp short throw shifter, KYB's and the list continues.....
'87 Fiero GT 4.9/4T60e w/3.33 final drive, ZEX nitrous 65hp shot, 88 cradle w/ 325# coil overs, Poly everything, Upgraded sway bars, KYB's, 16X7 M11's, 11.25 "Zettner" front brakes, Complete MSD ignition w/ 6AL box, Custom 2.5" Flowmaster exhaust, Grand Sport Corvette paint, Carbon fiber interior trim, '98 T/A CD w/ ETR, Reverse Indiglo guages, Pillar mounted AutoMeter O2, Hella H4 conversion.
Follow its built up here:
https://www.fiero.nl/forum/Forum1/HTML/027460.html
Sadly... SOLD.

quote Originally posted by BV MotorSports: I have had 2 turbo'ed duke fieros. Neither exploded but WTF do I know?

Nuthin!

------------------

****************************************
http://home.cfl.rr.com/fierose
Central Florida Fieroshttp://www.centralfloridafieros.org

ouch thats a shoot ot the ego, but can any one tell me how to accopmlish this

It's funny (ok maybe it's more distgusting than funny), but the people spreading the rumors about the frailties of the Duke are the the ones who have no or little experience modding or even working with a Duke. Ask someone who has actualy done something or who has the ability to use common sense and it's a different story. Non SD4 Duke are still fairly popular in various forms of racing.

Think about it, a stock Duke is 89-110 HP. So if I do some basic mods like headers, K&N, tuning ect. and gain 10 hp the engine is at it's durability limit? That's just plain idiotic. If GM had designed it to be so close to it's power limit we wouldn't be discussing it because it would not have been kept in production long enough to put in the Fiero. They had warranty periods they had to make it through.

Granted, some versions of the Duke had problems, so did small block Chevys. Do you see peole constantly claiming the will explode with anything more than a 10-20% power increase? There is no reason that most stock Dukes in sound condition couldn't safley handle around 150 hp. Over 150 hp durability starts to become an issue. A stronger crank, after market rods, and hyper or forged pistons should be used. Big deal. You wouldn't go from 200 hp to 400 hp on a SBC without changing those would you?

-According to Engine Builders magazine some Dukes came with hyperutectic pistons from the factory.

-The SD4 block was produced on the same production line as the truck blocks. The truck blocks have similar features as the SD4 block but have a lower nickle content in the iron used to cast them.

-Factory parts can be mix matched to create a strong yet enexpensive engine.

-Almost any performance part you could want is avaiable for the Duke if you know where to look.

The bottom line is: If you want getting a little more pep or being competative against a stock v6 is your goal, bolt ons will do the job reliably. If you want to do some mild or recreational racing a Duke can be built up with mostly production parts at a relativly low cost. If an all out race engine is what you want go with a SD4.

Erik-

quote Originally posted by erikred: Now I can answer your question. Yes people have done the turbo. It isn't that difficult, and is claimed to be worth while.It is hard to get accurate info on it though. Lucky for you, I am in the process of installing a turbo right now. I hope to have it installed with pics within the next 2 months, if my life will finaly allow me to finish this project. The most difficult part will be either adapting the turbo to the stock manifold or fabricating a new header. If you do the work yourself and shop at the junkyard it can be done cheap. Tunercat now has a definition file so the stock ecm can be tuned for the turbo, too. Erik-

just keep me informed and pm me with finall details/cost if u wouldn't mind

quote Originally posted by erikred: You wouldn't go from 200 hp to 400 hp on a SBC without changing those would you? Erik-

Actually, yes. A stock SBC bottom end should be able to handle 400 HP no problem.

GL

quote Originally posted by Tugboat: Actually, yes. A stock SBC bottom end should be able to handle 400 HP no problem. GL

Only if you are refering to certain ones. A LS1, LT1, or HP SBC could handle it. I am refering to the ordinary run of the mill economy SBC, such as a carbed 305 or even a TPI 305/350. They could probably handle the extra power, but it would cut the life expectancy. Which is the point I am trying to make about the Duke.

Erik-

quote Originally posted by erikred: It's funny (ok maybe it's more distgusting than funny), but the people spreading the rumors about the frailties of the Duke are the the ones who have no or little experience modding or even working with a Duke.

Well, it's no rumor, it's fact. I have worked with Dukes before, not hotrodding, just keeping them running. I'm on my third head (last two cracked, no overheating involved) and second block (first one cracked in the lifter galley) again with no history of overheating. Two machinists I have worked with have told me about the cracking problem, especially the heads. Call around and see how much the core charge is on a 2.5 head and compare it to a similarly common head like a small block Chevy. Around here the 2.5 core is $200, the Chevy core is $20 or less. Why? Because even though millions of 2.5 motors were built it is extremely difficult to get a rebuildable core due to the cracking. The core charge is in essance a "reward" for bringing back a rebuildable part.

Personally? If it floats your boat, go for it. I myself wouldn't spend any money on the head for porting and flow work because that will all be lost when (not if) it cracks.

JazzMan

I've already been down this road man, there was a complete of threads that people where trying to prove something but they never follow through. Search for a member called mrossom he had a duke build up thread. Honestly how the hell can you be satisfied with that amount of boost in a 98HP car to begin with, 8 psi is usually a 50% increase in HP in most cars so you are shooting for less then that i understand but common the amount of work it takes to get 120Hp out of your duke you could do a V-6 swap, You should have that laying around now (I hope) A duke was build primarily as a economy engine it has it's limits I'm unaware of them but not one person has set the bar adn that too much gamble for me.

If your not busy I'll take you or you can come to the next fiero meet on thursday, you know you want some quad 4 action. I'll be at tim hortons tonight too, get your cuz there as well. Hopefully your not too drunk from James 18th

------------------
Calgary - August 1, 2004 Fiero Fiesta
@ SouthCenter Mall

quote Originally posted by sergioazevedo: ok i am new i was wondering if any one has attempted to do this if u have or know any that has could some one direct me in the right way

It's your car, do what YOU want to do with it. You might do something we could all learn from...most certainly you will learn in the process.

I've never had a Duke, so I don't really know. But, everytime somebody asks about the Duke, the detractors are quick to point out what a worthless engine it is. Others say they've put 200,000 to 300,000 miles on them with no problems. Somewhere in between those extremes is the real truth. Go find it for yourself...life is too short to just follow what everyone else does.

Just to clarify my position on this subject. I am not in any way against hotrodding a Duke. It all depends on what the goals are when starting a project. If the goal is to increase power the cheapest way possible then a Duke wouldn't be the best candidate because you can get more for less buck with a swap. If the goal is to take on the challenge of wringing a lot of power out of a Duke then go for it, for it will be a real test of one's mechanical abilities.

The Duke is most definitely a very hard motor to get reliable power out of, many of those problems can be traced back to its origins as a light-weight emissions-oriented motor. If GM had added another 10% to the mass of the head and block in the right places it would be an entirely different proposition, but the fact remains that the head especially is a very lightweight casting known industry-wide for a propensity for cracking. At a minimum, to hot-rod a Duke in a serious way will require an SD head, and those alone cost more than the typical V6 swap. Add in a custom forged crank and other expensive goodies and you're already up into Northstar swap territory in terms of cost.

A decision to build up a Duke has to be driven by something other than cost.

Anyway, my 0.02 worth.

JazzMan

quote Originally posted by erikred: It's funny (ok maybe it's more distgusting than funny), but the people spreading the rumors about the frailties of the Duke are the the ones who have no or little experience modding or even working with a Duke. Ask someone who has actualy done something or who has the ability to use common sense and it's a different story. Non SD4 Duke are still fairly popular in various forms of racing. Think about it, a stock Duke is 89-110 HP. So if I do some basic mods like headers, K&N, tuning ect. and gain 10 hp the engine is at it's durability limit? That's just plain idiotic. If GM had designed it to be so close to it's power limit we wouldn't be discussing it because it would not have been kept in production long enough to put in the Fiero. They had warranty periods they had to make it through. Granted, some versions of the Duke had problems, so did small block Chevys. Do you see peole constantly claiming the will explode with anything more than a 10-20% power increase? There is no reason that most stock Dukes in sound condition couldn't safley handle around 150 hp. Over 150 hp durability starts to become an issue. A stronger crank, after market rods, and hyper or forged pistons should be used. Big deal. You wouldn't go from 200 hp to 400 hp on a SBC without changing those would you? -According to Engine Builders magazine some Dukes came with hyperutectic pistons from the factory. -The SD4 block was produced on the same production line as the truck blocks. The truck blocks have similar features as the SD4 block but have a lower nickle content in the iron used to cast them. -Factory parts can be mix matched to create a strong yet enexpensive engine. -Almost any performance part you could want is avaiable for the Duke if you know where to look. The bottom line is: If you want getting a little more pep or being competative against a stock v6 is your goal, bolt ons will do the job reliably. If you want to do some mild or recreational racing a Duke can be built up with mostly production parts at a relativly low cost. If an all out race engine is what you want go with a SD4. Erik-

Why does this always come up? What kind of experience does it take to count? Why continue to ignore first hand experience? I say the Duke is weak. You know what? I have three Duke blocks and cranks sitting in my garage. The sidewall and main bulkheads of those blocks are about .3" in most places. That's pitiful. The SD block is .7"-.8" thick on the sidewalls and main bulkheads. That's three times as thick.

Here are pictures that I took:

That's a cleaned up Duke rod. It's sad.

Again, my own crankshaft. It sucks.

Again this is my SD block and SCAT billet crank, 3.100" stroke. It doesn't suck.

I'm not trying to be cocky, just provide some credibility. I don't want to say anything that would end up taking this thread to the can.

Two questions:
What forms of racing are the stock Iron Duke blocks used in? Some websites would be nice.
Which bolt on parts will get you another 30hp to make it competitive against the stock V6?

The Iron Dukes are prone to cracking and failure if power is increased to any level beyond stock. Some parts are already at their limit.

Nate

[This message has been edited by FastIndyFiero (edited 06-12-2004).]

ok so what is the sd block casting numbers just so i can check to see if i have one

quote Originally posted by sergioazevedo: ok so what is the sd block casting numbers just so i can check to see if i have one

SD blocks are rare and expensive items. No SD blocks were placed in factory cars as far as i can tell.

It's pretty easy to tell:

quote Originally posted by JazzMan: Just to clarify my position on this subject. I am not in any way against hotrodding a Duke. It all depends on what the goals are when starting a project. If the goal is to increase power the cheapest way possible then a Duke wouldn't be the best candidate because you can get more for less buck with a swap. If the goal is to take on the challenge of wringing a lot of power out of a Duke then go for it, for it will be a real test of one's mechanical abilities. The Duke is most definitely a very hard motor to get reliable power out of, many of those problems can be traced back to its origins as a light-weight emissions-oriented motor. If GM had added another 10% to the mass of the head and block in the right places it would be an entirely different proposition, but the fact remains that the head especially is a very lightweight casting known industry-wide for a propensity for cracking. At a minimum, to hot-rod a Duke in a serious way will require an SD head, and those alone cost more than the typical V6 swap. Add in a custom forged crank and other expensive goodies and you're already up into Northstar swap territory in terms of cost. A decision to build up a Duke has to be driven by something other than cost. Anyway, my 0.02 worth. JazzMan

The worst part of it is the Duke weighs a lot more than most four cylinders of comparable displacement, as much as some V6s.

At least in the listings I've seen.

GL

Hey sergioazevedo. I have a turbo iron duke that I just finished and is currently running at 6 psi. Still have some bugs to work out but runs decently ok. I actually have Oslo's old turbo which was BV Motorsports turbo setup. I will be starting a new thread with finished pics in it soon. If you have any questions about the setup just PM or e-mail me.

-Frank

I do not wish to get into the argument about the Duke engine but I will say that the stock turbocharged 2.5L powerplant won't make much more than 130 HP. Still not bad though!
A company by the name of Pfaff pioneered the turbo kit for the Duke back in 1985. It was not a commercial success and the rights were eventually sold to IRM in Maryland. IRM manufactured and sold a few kits under the name HiTech but discontinued the kits shortly therafter. I spoke to Jim about this quite a few years back and he claimed that it was too difficult to get enought fuel in the engine and the stock throttle body proved too large an air restriction. While the boost was set to 5-6 psi, Jim had a few customers that went wild, raised the boost and toasted engines. JIm didn't want any more problems and dropped making the kits. .Read the road test in the the book Fiero Performance portfolio for more info.
Point is that if you want a little more pep, sure bolt on a turbo, CAREFULLY tune the chip program limit the boost to 5 psi and keep the RPM's below 5000. Sure you could up the power with more boost but it would be foolhardy to do so. Nothing wrong with a turbo Duke for a few more ponies , just do it carefully and do it wisely.

quote Originally posted by Kento: Nuthin!

LOL you suck!

sweet keep me informed about the kit and the how toos

quote Originally posted by BV MotorSports: LOL you suck!

You're Welcome