Ok here is the info on a 195 Hp Duke engine.Be warned in advance that this engine requires lots of TLC and you're probably cheaper to just swap in a V6. That said here goes nothing. First you need an S-10 truck block I used an 86 Block but then again my engine is not DIS. The S-10 Block is heavier than the stock Fiero Block. You will also want the S-10 Rods. The rods need to be polished The block is then bored over.040" The deck is shaved .045" and A good set of 350 Chevy flattop forged pistons is installed with Moly rings. Keep in mind you will also be spending the money to have the rotating assembly balanced. As far as the Cylinder head I used the HSC Fiero Head. The exhaust valve seats were cut out 1/8th of an inch and new seats installed. Also the exhaust side recieved some extensive porting and polishing. The intake side was also reworked in the bowl area and Intake and exhaust manifolds were then port matched to the cylinder head.Be careful if you're not having this professionally done I do it for a living and still destroyed one head getting the porting job right. This motor needs to spin to make HP so a cam is a must I found that using the same cam as the mercruiser 185 Horse boat engine yielded the best results. Also Federal Mogul makes a set of all steel timing gears. The gears are cut so you can advance or retard the cam timing in relation to the crank this shifts the HP peak in the engines RPM range. Currently I'm running with the cam at 4 degrees advance to bring the torque peak down in the rpm band. The extra RPM necessary to make HP from the duke requires a very hefty set of valve springs I used a set of edelbrock performance springs with extra .030" shims as well as the stock spring shrouds. The valve train assembly is currently stock that is the stock 2.5L rockers are being used. Going to rollers in the near future I hope. The cylinder head also needs to be planed .025" in order to bring the compression up a bit more.Final CR is in the neighborhood of 9.8:1. You will need a decent header the hooker works nice. Also the ECM will not be able to compensate for all the changes. You can either find someone to burn a custom chip or If you have the patience fool the ECM with a resistor box. I went with the Box for now but am looking into a TEC II system when I get my pennies saved up. Ignition is handled By an MSD Blaster coil and 8.8 mm Accel Custom Wires. I think thats about it if I think of anything else I will add it to this thread. Any questions or comments Feel free to E-mail me directly. CYA!!!!!

What exactly do you mean by extra RPM.. are you talking a 6-7K RPM duke.

Good job with the power, and you succesfuly avoided superduty parts so cost was probably.. . . resonable. Good luck and hope it stays together for ya.. the duke is a nice engine, it just needed more power.. you found it

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NOCONES
-84 2M4
-4.10 4-speed
-for sale.. .. perhaps
-SCCA sollo II
UPDATE
1986 SE 4-speed
V-6 :)

Addmit it... it's just as much fun alone... Solo II

what about forgoing the ecm and getting a carburated s10 engine? About how much did this cost? can you make part numbers available?

Wow, sounds like you did most of the stuff I am planning. I thought I would have mine together by now, but my wallet won't let me!

I never heard of the 185 hp Merc., I thought the highest was 140 hp ?

How long have you been running this engine? Have you had it dynoed? What is the Fiero like to drive now?

What was the total cost in machining and parts you had?

Thanks for the post, I've been waiting to hear some results as I know there are several people out there building Dukes right now.

Erik-

What's a Tec II?

For all of the trouble that it takes to build this super duke engine, I would think that it would be far less expensive to install a built V6. I find it hard to believe that a Duke can make 195HP without a turbo but anything possible if you try hard enough. I can appreicate the work that is going into this engine but I have a question- What is the point of this build, practicality, cost or ego?

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87GT 3.4 Turbo Best 0-60 5.2 seconds
http://turbofiero.fierojoe.com/turbo.htm

This may be a stupid question but I thought the S10 ( and all RWD Duke blocks for that matter) were slightly different due to the mounting points. Did your RWD Duke block bolt up to the Fiero no problem?

quote Originally posted by Dennis LaGrua: For all of the trouble that it takes to build this super duke engine, I would think that it would be far less expensive to install a built V6. I find it hard to believe that a Duke can make 195HP without a turbo but anything possible if you try hard enough.

That's why he said that in the original post!

There is only .3 liter difference between the v6 and Duke, and the Duke can be stroked to 3.0 liters easily. Why do you find it hard to believe it could make 195 HP? An SD version can make in the neighborhood of 400 hp without a turbo or nitrous. Also, to build a Duke as described (assuming all assymbly was done by the owner) would be less than the cost of a remanufactured Duke or v6. You have to remember you will end up with a freshly rebuilt engine as opposed to a worn out one. In fact, the build up I have planned will be around $1000 including forged rods, forged pistons, HiPo cam, alloy gears, new valves, all new high quality gaskets rings and bearings, and all machine work. I will also be installing a turbo and Crane DIS spark box which are included in my budget. My goal is 250 hp, but I am not to sure of the capabilities of the cylinder head right now.

Erik-

Which crank did you use? What about fuel and induction? Stock TBI? Holley TBI?

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Raydar

From the Department of Redundancy Department.

quote Originally posted by 30+mpg: What's a Tec II?

Total Engine Control - often used by hotrodders to add electronic ignition and all sorts of other computerized goodies to old carbed or low electronics cars. They're downright amazing. We have one on our Formula SAE competition car at University.

They come with a serial cable hookup, so you can tune on the fly with a laptop. Very cool stuff. Wanna lean it out a little? No problem. Fatten it up? No problem there either.

They're also very expensive (well on the other side of a grand if I recall correctly; we bought ours used for $600, but I don't remember if that was Canadian dollars or US dollars.

Hope this helps a little - I actually don't have a whole lot of experience, but I noticed your question was going unanswered

Cheers,
Andrew

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Andrew - 85SE - AKA Fieroless in Newfoundland :(

Ok to answer a few questions. The engine was built for the heck of it. I've seen lots of V8 Fiero's and lots of V6 Fieros And thought why not do the 4 cylinder since it has lots of potential. I suppose ego may have played a role as well....lol. The dyno numbers are rear wheel dyno numbers a friend of mine has his own water brake dyno that they use for tractor engines so we put it on one night just to see what the thing was making.

Sounds like that duke powered fiero would put quite a few V6 powerd fieros to shame!

You should take it to a show sometime. Maybe get some pictures of it posted here. What times are you getting?

I haven't had a chance to run it down the 1/4 yet to be honest so I don't have a valid time slip yet. Still waiting for the snow to melt here...lol. I will post them when I know. The few times I've had the car out to street race though I usually get asked if its a hopped up V6. Most people are amazed when I pop open the deck lid and all thats there is the Duke.The other thing I get asked alot is where I hide the nitrous bottle......lol. I can hardly wait to get a nitrous system for it but dollars are tight at the moment. I'll post some pictures as soon as I can. Don't have a digital camera so I'll have to borrow one. I think someone asked about reliability too. Again don't know what its going to be like yet but I am hopeful. I think that if the engine fails it will likely die a spectacular death......lol.

Another question about the block again......
Does the S10 block have provisions for hte external water pump?

quote Originally posted by TheTechnician: Hey erikred just so you know the Fiero is great to drive now....lol. It definitely needed the extra ponies. I would also reccomend that you use a crank girdle if you can find one for the 2.5 Block. I didn't but its probably a really good Idea. I'm also planning on going to a 100hp wet nitrous kit when I can afford it. If anyone has a decent used one let me know.

I have wondered if a girdle would help, the Ford 5.0 guys use them. I know how the girdle is installed but how does it strengthen the bottom end?

Erik-

Hank the bolt bosses were on the block I got again just had to be tapped. And Erik the girdle increases the rigidity of the web area of the block. I'm not even sure whats available for the 2.5L but I'm sure the off road market must offer something. Since this engine is basically an experiment at present I haven't really looked into a girdle yet. Thought I'd see if it would hang together without it.

quote Originally posted by Dennis LaGrua: For all of the trouble that it takes to build this super duke engine, I would think that it would be far less expensive to install a built V6. I find it hard to believe that a Duke can make 195HP without a turbo but anything possible if you try hard enough. I can appreicate the work that is going into this engine but I have a question- What is the point of this build, practicality, cost or ego?

because he wanted to build it is the answer to that question. why do you ask ****** questions..................

I am glad to see that he did it. it proves my point like he said it will take alot of tlc it you dogg on it or any engine its going to brake some thing sooner or later

quote Originally posted by Dennis LaGrua: For all of the trouble that it takes to build this super duke engine, I would think that it would be far less expensive to install a built V6. I find it hard to believe that a Duke can make 195HP without a turbo but anything possible if you try hard enough. I can appreicate the work that is going into this engine but I have a question- What is the point of this build, practicality, cost or ego?

Because he wanted to. You chose a turbo V6, I chose a SBC.

So what? To each their own. Personally I have no interest in building up a duke, or a V6 turbo, but this tread is very interesting.

Great work Technician, and congrats dude!
Like someone already stated, the duke is a great little motor, just needs more grunt.

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quote Originally posted by jelly2m8: Because he wanted to. You chose a turbo V6, I chose a SBC. So what? To each their own. Personally I have no interest in building up a duke, or a V6 turbo, but this tread is very interesting. Great work Technician, and congrats dude! Like someone already stated, the duke is a great little motor, just needs more grunt.

my thoughts exactly... if everyone did the exact same things to their cars this forum would be a pretty boring place... 195 HP is still 195 HP and thats something to be proud of! especially comeing from a duke.

quote Originally posted by TheTechnician: As far as the Cylinder head I used the HSC Fiero Head.

Not to sound ignorant, but what is the HSC head? I have an 86 Iron Duke....

-Karl

nice job!!

if I ever decided to build an Indy Fiero, I'd probably do a project like this, and dress it up as an SD4... (valve cover, air cleaner, etc)

I just have one question, approx how much did it cost? I can't be the only one here curious about this project.

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steve@digitalfusion.on.ca
http://www.fieroproject.com

[This message has been edited by DaRkLoRD (edited 04-19-2002).]

Me too.. VERY interested in this, in fact, i went junkyard divin for the block Out of curiosity, why wont the Fiero Block work?

-Karl

quote Originally posted by FieroJones: Not to sound ignorant, but what is the HSC head? I have an 86 Iron Duke.... -Karl

Technician, correct me if I am wrong, but I think HSC stands for High Swirl Chamber.

Also, FieroJones, the s-10 block is known to be stronger than the block that came in Fieros. This doesn't mean you cannot use the Fiero block though. It hasn't been proven how much the Fiero block can take though, so you are better to go with the S-10 block.

Erik-

In reply; Great work by the technician for sure and certainly he did it because he wanted a unique project. His work is both unique and interesting and if he did it to make himself happy that's great. I just question the cost effectiveness per HP of such a project. My thinking is that you build an engine for the max power for the money.
As for the comparison of the Duke to the potential of the Super Duty Four:
comparing the Duke engine to the Super Duty Four is like comparing a Rolls Royce to a Geo. The Super Duty Four was especially built for racing applications. It is a fine breathing super strong engine with and is capable of sustaining hi rev operation for a long periods of time. In contrast the Duke is a light duty poor breathing, engine with a recommended redline of only 4500 RPM. The Duke was developed for economy. The Dukes power potential is extremely limited especially at the bottom and top end. Add a turbo to it and you'll get about 145 HP but a shortened engine life. These engines also don't respond well to NOS.
Fieros with Duke engines are certainly nice, but the point that I am making is that you'll always make more power with the same mods applied to the V6.

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87GT 3.4 Turbo Best 0-60 5.2 seconds
http://turbofiero.fierojoe.com/turbo.htm

Thanks Eric. So do the Fiero Iron Duke's have the HSC heads, or is that somethin that you get done when getting head work? Thanks also on the Engine block, thats what i thought, but thought i would just double check.

Dennis, Its not about the "you can get more for less with this" that I am after. Its going for the Stock look on an Indy. Or that "look what i did!" feeling. I imagine this is the same line that was given to YOU when you first said "I want to put a Turbo on a V6" and all the V8 guys said that it wouldnt be worth it. Now I imagine that in your mind you proved them wrong. Now my question, why are you givin the 4cyl so much flak?

Once again, thanks Eric and thanks Technician!!

I have tryed to find the specs on the mercruiser 185 cam but found none so i have tryed to come to the closest hp ratings he got from the duke on my decktop dyno 2000

BORE:4.00 STROKE:3.00
Low Performance/Ported, Large Valves
Intake valve: 1.90 Exhaust valve: 1.50
compression: 10.1
induction flow: 300 cfm
Exhaust system: Small-Tube Headers With Mufflers
Cam : roller http://www.ultradyne.com/
cam Int & Exh duration: @ 0.050 223.0
cam lob center: 110.0
cam lift int & exh: 0.548
Top HP:5500 rpm at 199
Top Torq:4500rpm at 203

Has any one tryed to stroke a duke? Crankshaft specialest out of memphis tn said you can go as far as 3.4 (cost is $450) with out cuting in to the side walls of the block for clearence.

"Now my question, why are you giving the 4cyl so much flak?"

I'm not trying to dictate to anyone on how to spend their money or what engine to build. I just simply state my opinion, raise questions and participate in the open exchange of ideas and opinions like everyone else on this forum.
To those building a performance Duke engine their ideas and opinions are interesting to me. I wish everyone the best and hope that they will succeed.
If I seem a bit negative on the Dukes performance potential it is based on my research, discussions with other engine builders and a few guys that I know that tried a performance buildup and were disappointed with the outcome.

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87GT 3.4 Turbo Best 0-60 5.2 seconds
http://turbofiero.fierojoe.com/turbo.htm

TheTechnician, is fierojones, pretty close with the specs??

the buildup seems pretty cheap. Compared to other swaps. And i could probably get a block for 50 bucks. And i just got done with a class on rebuilding engines.

when u first installed the engine, how does the ECM react? And can you explain more about what needs to be fixed to get it running correctly.

Will the modded 2.5l pass emissions?

Have you tried the older S-10 heads? They don't have that annoying little hump in the middle of the intake runner taking up precious space that could be used better by air and fuel.

I'm very curious as to some of the mods, but I can only run a balanced and blueprinted motor in my class that I race in. With a b&b'ed motor and metal timing gears, I see 5500rpm on a regular basis. Oh yeah, that, and lots of oil in the system. An oil cooler and remote filter at least, but I've also got a 3qt. Accusump as well

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SCCA ITB '84 Fiero 2M4
AOL IM- DGPFiero

Wow I need to log on more often this thread has gone a long way since I was online last. I guess I should answer a few questions. First of all WHY? The answer is simple it was to see if I could make that kind of HP out of a duke engine. I own an automotive repair and performance shop so it was sort of an advertisment ego trip and fun project all rolled in to one. Fiero jones is close on the specs CR is actually 9.8:1. I got the car for a set of axles I installed in a Ford Taurus. Previous owner couldn't pay me any other way. So I think it cost me about $200 canadian. The previous engine was whipped so I got reading and researching and decided what the hellmight as well give it a shot. I have to admit the first attempt failed miserably. I used stock pistons and every one of them collapsed due to the RPM. Thats why I'm running the 350 chevy Forged flattops now. Stronger skirts allow the higher revs. Plus I have 4 spare pistons if anything goes wrong. This is also the reason that the block deck and cylinder head have to be shaved so much. The chevy pistons are about .032" shorter on the deck height. I'll answer a few more questions in my next post.

which part of the project cost $200 canadian?

I know the 350 pistons etc are more than that.. unless wholesale is a lot cheaper than I suspected.

thanks for the info btw, this project is fascinating!

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steve@digitalfusion.on.ca
http://www.fieroproject.com

Ok gonna answer a few more questions... The build itself cost about $1500 this does not include countless hours porting out the head which I do inhouse at my shop. It does include the cost of the junkyard engine. The HSC head is whats on your duke engine right now FieroJones. Oh yeah the cost of doing the engine twice is not included in the $1500 price tag. See my post above about why I did it twice. The resistor box is a home built unit that I use to modify sensor signals to the ECM. I'd advise that if your gonna do this build Use an aftermarket injection and Ignition system like a TEC II. The resistor box is a really crude way to do it although it does work I'm switching to a TEC system as soon as I have the bucks. I'll answer a few more questions in my next post keep your opinions coming.

Any info on where to get a TEC II box? I'll have to check on if I can run that in my class. If not, the resistor box sounds like it would work. Also, anybody know of anyone that can reprogram ECM's? I need more timing advance (MSD's website has a really nice rotor assembly for a std. Duke, but no info), and tailoring the fuel curve would be nice as well.

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SCCA ITB '84 Fiero 2M4
AOL IM- DGPFiero