3.4L DOHC performance rebuild

[pontiac92gp]

Im thinkin bout sendin my engine to a machine shop in town for a rebuild. The only thing is .. I just dont want a plain rebuild .. I was wondering if I could put different cams or cylinder heads or are they aftermarket pistons(bore it out?) or something to gain around 40hp?

So i was wondering whut kind of possibilities there are? I would like to keep it all motor .. but is a turbo a better way to go?

Thanks for any input .. aprreciate it ..
92 Prix SE w/ 3.4L TDC and getrag 284

[robby1870]

Talk to fleetwoodguy79, hes done a performance rebuild of a DOHC. Hes not on this board, I dont think, but his AIM name is fleetwoodguy79 Tell him you heard of him from Robby1870 or from the W-body boards

[SappySE107]

Turbo would give you a lot of extra ponies. To gain 40 hp, you can simply change your cam timing to 13 degrees retarded on the exhaust side, FFP chip, and have the heads ported.

You dont need to worry about pistons really, unless you want to run some boost. otherwise, just get some stock replacements (hyperuetectic). Rods, you can run stock but I would have them polished, deburred, and shotpeened. Have the crank balanced, and get moly or total seal rings. Cams, you can have a regrind done but I dont know the specs yet so I can't share any more on that other than it costs 477 bucks to have them done.

[bwawuz02]

have you put them in yet? results?

[SappySE107]

no.

[blk92z34getrag]

Where are the power gains from retarding the exhaust cams? i.e. low-end, top-end, etc. Also does it affect the exhaust tone? Reason is I'm concidering doing this eventually, also are there any ill effects?

and yes, I know I'm getting ahead of myself (still haven't gotten the stalling under control)

[Anonymous]

Retarded exhaust cams = ++Top-end

It also gives the idle a bigger lope. Dunno about the tone.

Ill effects: possible loss of low-end (wouldnt really effect you cuz of the 5spd).

[pontiac92gp]

Heh .. is brian89gp gonna update his website .. so damn interested in his project .. I crave the knowledge to turbo the 3.4L TDC ..

[pontiac92gp]

Do you need to change your compression when adding a turbo? Need different manifolds? You guys sed that the Supra turbo in the 3.4L TDC is good for 350hp .. would that blow the transaxle / burn out clutch in no time?

[ryan.hess]

bump because I'm curious also

[brian89gp]

Update?

The Toyota CT-26 will work but if I were to do it again I would look for a Garrett model, easier to find and easier to rebuild. The CT-26 is on the bottom edge of the usability range, it would be much like the TGP with little to no lag and limited potential. It is a good place to start though. HP, 350 for a stock CT-26 seems high, it might be possible but I would only hope for the 300-325 range. Mine has a Garret T4 compressor wheel in it and I am only expecting 350-375.

The 4t60-e would live a short life. If you lowered the shift points all to under 6000 it might help, but it would still die a lot sooner then normal. Mine the torque converter burnt up and it started shifting real slow (slipping) within 2 months of 1-2psi of boost. If you use the CT-26 you can expect to have boost at 2500 or below, one time my wastegate hose blew off and I hit 8psi at 3000.

The Getrag 284, stock clutch probably wouldn't be wise. SPEC, Clutchmasters, and ClutchNet all make performance discs and can all re-arch the pressure plate so I wouldnt worry about it too much. I would either go with the 284 or a built 4t65e.

Compression, it would be wise to drop it some but its not necessary. Depends on your self control. The rear manifold will need to be changed, a custom crossover, and then wedge a downpipe through the mess.

[Anonymous]

I rebuilt my 5-speed a little while ago, pretty much a stock rebuild with some good parts. I used Total Seal rings, bored .030 over with forged alum pistons, decked the heads for .25:1 more compression, and so forth. The car runs awesome, and it is faster than before, a good deal faster.

And horspower won't go through a clutch fast, a bad driver will. Just don't ride it. My clutch is either in or out, never in between. The 3.4 already eats clutches though, so on race launches it will not last long.

You won't ever get the stalling/rough idle under control. ALL 5-speeds jump up and down 200rpm or so at idle from 800. Down to 600, up to 1200, etc. Mine does it, Bowtiekid79's car does, every one. I replaced my IAC and it helped tremendously, it rarely dies now, but still gets close. Also, try not using turn signals when coming to a light. They create a varying draw on your alternator, which is fine on most cars, but ours seem to not like it. It helped my car, with turn signals it died a lot more.

[SappySE107]

all 5 speeds...mine doesn't. Maybe all luminas do:P ok so i think its the elevation and the computer programming for the IAC. Mine is pretty damn dead on and smooth. It only revs up to 2000 when coming to a stop if I was going above 35 or so and the heater/ac has to be on for that to happen. ill find it in the spring to fix that problem.

[pocket-rocket]

Mine doesn't die. It used to, then I changed the intake gaskets that went bad, and put the vacuum hose back on the FPR and it works fine now. The 91 barely even has a stalling problem either, and that engine is so worn out you can hear the bottom end in the morning when it is started cold. New bearings will take care of that this summer.

[brian89gp]

Mine tends to fluctuate with the idle. Course I am using an auto chip in it I found that raising my idle up to 1000 solved a lot of the surging and stumbling.