how much HP can 3400 handle

[tejohnson]

95-2001 UPDATE, (2002+ does not need this as it has the updated regulator valve and spacerplate) spacer plate kit, 24224336
and while your in there put in a new pressure control solenoid 10478146

besure after this to clear your trans adapts, (will need tech2 to do so)

Thanks! As for the adapts, I have been programming my PCM "Offboard", and have already uploaded a modified calibration to the PCM almost 4-5 times already with DHP's PowrTuner software...

Re: http://groomlakelabs.com/gallery/DHP

[2M6]

WOW.....

I clicked on this thread to see how much power people are getting out of their 3400s because I am getting ready to build one for my Fiero. Everything I got from these four pages was useless info to me since I have a 5-speed. If I was a moderator I would have split this topic by the 4th post and titled it "Tranny discussion-which is best" so this one could stay on its origional topic. I admit there is a good amount of useful info in this thread, it just doesn't belong in it.

To get back on topic, what seems to be the weak link in the 3400 for power levels above 250hp at the crank? My goal is ~275hp at the crank with a high compression normally aspirated build. What is a safe CR on 91 octane with an aftermarket engine management such as SDS or something similar?

My plans are to upgrade to forged pistons and go with stronger (LS1?) valve springs. I will consider a custom grind cam if it's worth the money. Any other suggestions?

[sharkey]

to get 3400 NA to put ot 275hp is gonna take a lot of cash. you are going to need to get high compression (12:1), beam polished rods, or sbc rods, lighten and knife endge the crank, forged pistons, custom ground cam (currently are no cams for the 3x00 motors, unless you retro a gen 1/2 timing set and use a cam for one of those motors) ported heads, stainless valves, headers, bigger tb, ect. you will need to run stand alone on it, as a beast like that will need some serious custom tuning.

[Froggx]

WOW.....

I clicked on this thread to see how much power people are getting out of their 3400s because I am getting ready to build one for my Fiero. Everything I got from these four pages was useless info to me since I have a 5-speed. If I was a moderator I would have split this topic by the 4th post and titled it "Tranny discussion-which is best" so this one could stay on its origional topic. I admit there is a good amount of useful info in this thread, it just doesn't belong in it.

To get back on topic, what seems to be the weak link in the 3400 for power levels above 250hp at the crank? My goal is ~275hp at the crank with a high compression normally aspirated build. What is a safe CR on 91 octane with an aftermarket engine management such as SDS or something similar?

My plans are to upgrade to forged pistons and go with stronger (LS1?) valve springs. I will consider a custom grind cam if it's worth the money. Any other suggestions?

Pistons are generally regarded as the first thing to go. Forged pistons solves this problem nicely. Lightening up the crankshaft/con rods would be a good idea. From what I've heard (no personal experience) the stock crank and rods can handle at least the 275 hp you're going for. The way I see it you're going to need a rather aggressive cam, head porting, headers + exhaust, maybe custom plenum, etc to hit that power level. Of course, fiero drivers are famous for being extra resourceful so you shouldn't have much trouble with those things. I would vote a path that sacrifices some low end torque for top end power in an NA build for these. Have you looked at the DOHC 3.4 motors? Debatably they are easier to build for power if you can find one that hasn't chewed itself to pieces.

[imported_germ]

blah, just slap a big as turbo on it.

10 psi, easily 325+ crank hp if done right.

[Froggx]

blah, just slap a big as turbo on it.

10 psi, easily 325+ crank hp if done right.

[bszopi]

I've thought about splitting this thread, just haven't gotten around to it. Maybe I'll do it later....

[AaronGTR]

The stock internals can handle 275hp at the crank easily. I'm over 300 at the crank with no engine problems so far (using boost of course). Only major problem I've had is the transmission.

If you plan on getting 275hp NA though, that will be quite a task. Most NA 3400's I know of are running under 200whp, but aren't completely built. You'll need custom internals with forged high compression pistons and everything lightened and balanced so you can rev it higher (power=torque x rpm). Ported heads, headers, maybe extrudehoned or at least port matched intake manifolds. A cam would definitely be necessary to get more power out of the top end. Milzymotorsports has a small run of custom 3400 cams coming out, and supposedly comp is still developing a 3400 cam. You'll probably want gapless piston rings, and maybe some of the new high tech piston and cylinder head coatings. Anything to optimize the engine's thermal efficiency and reduce friction. Then you get all the fun of tuning it. Since you have a manual trans, I would recommend going the stand alone route. Have fun...

Personally I'd go with Germ's recommendation and boost it. You get the power increase without the loss of low end torque, and it will be cheaper in the long run I think.

[TurboZ24]

Yeah, I was going too also say boost is probably the best way too maintain good overall powerband and producing some higher HP numbers. A high HP NA motor doesn't usually have a real good powerband, it's mostly all up top.

With a stock 3.1 (not 3100) with head work and cam, you can basically hit that 275 crank HP with just 6 psi. That's what we got out of Steve's wagon, 229.1 wheel HP and 261.7 wheel ft lbs at 6 psi, so like 265 crank HP and around 301 crank ft lbs (assuming a 15% drivetrain loss).

Oh, and a stock 3.1 crank, you shouldn't worry about those, mine is still stock also. As for mileage also, mine still get's upto around 29 mph highway (unless I drive like an ass).

[Berettaspeed]

Im planing on using an air to water(i think thats what you call it) intercooler. I already have most of the stuff. its just a matter of fabbing everything up. I think im just going to run around6-8psi thats it. the turbo im using is a mitsubishi, but not off a mitsu??????
mmmm

Im worried about the tuning. its easy to get everything to fit in place and work, but tuning is going to be a pain. i just hope i don't ruin anything.Funny thing is i know nothing about turbos, so this whole thing will be a learning experience.

[2M6]

My plan is..
11.5:1 CR
Forged pistons
Ported/polished heads
Custom ITB intake manifold with short runners
SDS engine management
Lightened crank
SBC forged rods


If all this proves to be too much $$$ for too little power gains I may boost it or do a whole different engine/trans combo (not 60* V6)