I am looking for your best "educated" guesses here, as I know without putting her on a Dyno, we are just guessing!
The 3.4L is from a 1995 camaro, with about 80K miles on it. Good compression, no leaks, nice engine. Used this long block and transferred all of the stock Fiero intake, exhaust, sensors, etc onto the 3.4 The Fiero is a 1985 GT.
The Fiero throttle body is bored out slightly, but I can't find the numbers on how much it is bored out - - -
Manifolds and Plenum are ported to the 3.4L heads
Accel 8.8mm plug wires, with cap, rotor, and coil also by Accel
Fierostore.com High pressure / high flow fuel pump installed
adjustable fuel pressure regulator installed
Flowmaster muffler, and cat converter test-pipe installed
RD stainless steel vacuum line kit installed
power pulley kit installed
So, I am curious, with this set up, what do we realistically expect this mill to make ??
The stock engine, when it was in the Camaro, was rated at 160 ponies, and 200 ft-lbs torque -
Ooops! I forgot - it also has a lightened or lightweight flywheel,
and a big bore cold air intake, with the big cone style air filter - not sure if they would have any effect on power output or not -
And I suppose I should have mentioned I am running the Muncie four speed manual transaxle, not the evil automatic !
Thanks for any and all comments, suggestions, and encouragement !!
[This message has been edited by Fastfocusguy (edited 04-17-2015).]
This is a Tech section after all, so while guessing may be fun, most of us try to stick to the facts. How much could it cost to find out the answer? We have seen some pretty tall tales over the years...
[This message has been edited by Gall757 (edited 04-17-2015).]
I had a similar setup but I had more goodies added. On top of what you have I had trueleo intake and exhaust, 260 cam, 1.6 full roller rockers and p&p heads. I think I was at 205 - 210 hp. I still have most of my parts to get rid of since I have a 3800 now
I agree 140~150 to the wheel if you can get to the rated flywheel HP of the Fiero except at the wheel you are going to feel the difference if that's what you are worried about
When my 3.4L was a new crate engine, with a 440T auto, I had it dynode and it dynode at 118 HP @ 5000 RPM at the wheels. It was done in third gear and it was running 142 mph at 5000 rpm. If you figure a 30% loss in HP going through an auto transmission, It calculates to about 150 at the crank.
When my 3.4L was a new crate engine, with a 440T auto, I had it dynode and it dynode at 118 HP @ 5000 RPM at the wheels. It was done in third gear and it was running 142 mph at 5000 rpm. If you figure a 30% loss in HP going through an auto transmission, It calculates to about 150 at the crank.
Absolutely zero knowledge, but this seems about spot on to me. A 160hp engine with a little intake restriction (versus the Camarobird intake) sound like a 150hp engine to me. All the fancy fuel and ignition bolt ons won't change the intake manifold one bit - I wouldn't expect anything from them.
But, really, the horsepower out of these old pushrod motors is not the attraction. It's the sub-4k torque. The 3.4l makes the Fiero feel like a rocket ship for the first 30 or 40mph. Neck-snapping clutch drops for everyone!
I'm guessing 160, tops, if you are running the Fiero upper intake. That will work out to 120 or so, at the wheels. The Fiero upper is a huge bottleneck for a 3.4. It's barely enough flow for a 2.8. Boring the throttle body will have next to no effect at WOT, anywhere near redline.
As others have said, the 3.4's strong point is it's low RPM torque. Just short shift, and enjoy it.
I might have gotten 200 out of mine (never dynoed it either) but that was with a trueleo intake, and about $800 worth of head work, a 272 cam, and the appropriate springs. It felt almost as strong as my 4.9, minus the tractor torque.
As posted above, with the stock Fiero intake manifold you will be making less than the 160HP the engine made in the Camaro and probably around 150HP as also stated above. If you get the intake from WCF installed and the additional fueling requirements dialed in you are probably looking at 185-200 flywheel and 160 to 170 at the wheels on a dyno. That would be my next investment if you are looking to stay with this engine.
Some people still confuse rated engine horsepower with rear wheel horse power. 160 rated engine = ~135 rwhp in a Fiero. The stock accessories and transmission consume about 25 hp... Which is why a stock 140 rated 2.8 dynos at 115 rwhp. Don't expect much over 140 since you didn't change cams...which is the biggest initial limitation and ultimately controls how much air your heads may desire. While you had it out would have been the perfect time for a cam upgrade. Your best bet right now is to go with 1.6 full roller rockers if you are looking to get close to 150rwhp. You should also remove the Y pipe restriction.
Don't know a number, but with the Fiero intake, dizzy and ECU, UNtuned, it will definitely make LESS power than it made in the Camaro, even with your other mods.
Will a lightweight flywheel and transverse transmission allow it to match the stock Camaro output at the wheels? I don't know.
[This message has been edited by Will (edited 04-19-2015).]
I've driven Fieros with the a stock 3.4L P/R engine swap. The low end was stronger but the top end power seemed to drop off. Several years back Fierochic ran a 14.9 1/4 mile time with hers so the power has to be superior to that of a 2.8L.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
The guys saying 150 are likely correct. You've done nothing to increase power and in fact have used bits that reduce power.
You need to go through the heads, intake and exhasut and make the well known mods that improve flow, and you also need more cam and high ratio rockers and...... The stock heads are the same as the 2.8 and flow sucks, at least compared to modern heads, and the restrictions in the exhaust cost another 12-14 bhp. Having a larger TB does nothing if the engine can't use more air. Stock 3.4s run out of suck after about 5,000 rpm.
I run a 3.4 that I've gone through and puts out around 200 bhp and that is a world of difference from a plug in 3.4 with Fiero stuff on it. I am about the same performance in my car (not a Fiero) as a similar car with an alloy V8.
According to the OP, aside from boring out the TB, he ported the manifolds & plenum, as well as used the power pulley kit, flowmaster exhaust, and straight-pipe cat. Not a truleo intake, but still.
Intake mods are basically ineffective unless accompanied by serious surgery to enlarge the neck of the Fiero intake manifold between the throttle and plenum.
[This message has been edited by Will (edited 05-01-2015).]
If you put in a big cone-type "cold air intake" then you probably now have a warm air intake that pulls in from the engine bay vice the outside air, which is a step back from stock. I did the same thing when I was younger, till I looked at it and saw my purchase made no sense, lol. I just went with the K&N filter you can drop in the stock can, but I doubt it helps that much.
