I'm new and I want a 3.4 DOHC

[vinny]

Hello everyone. I have a 88 Fiero gt that I'm wanting to do a swap on in the near future like the first part of next spring. I have thought it over pretty good and decided to go DOHC. I choose this motor because I think its a great choice for the Fiero. I have bypassed 2 N*s, 1 Olds 4.0 and a 3800sc. I know I'll need lots of help and guidence so what better place than 60DegreeV6.com. Oh yeah and Pennocks Fiero forum.

1)Is it realistic for me to build a 300HP 3.4? If so what would be a good combination of parts and machine work?

2)If I choose to go turbo what is the best rout to go turbo wise. I've heard the stock turbo on a Buick GN was a good size.

3) I believe in being economical so I'm not afraid of used parts or Diy advise!

Any help or advice on collecting parts would be great!


Vinny

[z34phoenix]

to realistically build a 300HP DOHC motor it would have to be boost. NA it would be a stretch.

for turbo your best chocies i think would be the older 91-94 block due to the lower compression of 9.5 vs 9.7 and run a 96-97 intake manifold set. the newer intake manifold makes diff TB's much easyer. also the longer runers will give better Tq for when you are not in boost.

get a set of 2 front exhaust manifolds from the 91-95 motors... i beleive it is the 95's that dont have the AIR ports drilled into them... these would be ideal. using two front manifolds makes for an easyer design of a turbo crossover.

as for turbo size, it all depends on what you want... if you want a drag car? a daily driver? or AutoX beast. from what i have heard a t3/t4 hybrid or t04 is what most have used. as im sure you know by now, aftermarket is almost non existent now... even less then it was 2-3 years ago.

[dohcfiend]

I believe 300hp n/a can be had but it wouldn't be cheap. It would probably cost just as much as the turbo kit. at that point, it depends on your preference.

N/A if you get the heads ported, cams done, few ud pullies, headers, free flowing exhaust, 96-97 intake, 96-97 heads, computer tuning and a few small bolt-ons, i believe 300hp can be had.

96-97 heads are definately the better choice for n/a and the best choice performance-wise for turbo. As z34pheonix mentioned with the symmetrical exhaust ports, unfortunately it is a feature that the 96-97 heads do not posess so if you used 96-97 heads, turbo headers or manifolds would have to be fabricated. The 91-95 heads would be overall a more "economical" choice for turbo. i think the status quo is/was a t4 60 turbo.

[MOTORHEAD]

i got a 92 3.4 dohc block w crankshaft, rods, pistons, i have the assembly to the engine except for valve heads..

[vinny]

Thanks for the info guys. I'm going to the Super Chevy show this weekend in Memphis. If any luck I may find one there. I know where one is in a Cutlass but its only good for parts I would imagine because the hood is gone and its been at the mercy of the elements for a couple of years. The owner wants $100 for it firm. I may still get it though. the heads are probably good among other things and they will only get harder to find. A buddy of mine may also have a lead on a whole Z34 for about $500.

I was planning on some port work here and there. Also reground cams. I read somewhere I believe on here there is a guy that will do regrinds for $100 a cam. Is this true? If it is how did they turn out?

[Emc209i]

http://www.fiero.nl/forum/Forum4/HTML/041879.html !!!!!

[RedZMonte]

turbo would be the easiest way to get 300+hp. Im making 290hp to the wheels on 7psi and timg is making 325hp on 10psi... all stock internals and both are a '95 engine. there was a fiero guy a while back making 400hp w/ a DOHC turbo (don't recall the boost). and i think timg is building a engine and looking to reclaim the highest HP dohc title

OR.... do a 3800 S/C.. i know its been done alot but its a strong motor and ALOT of aftermarket.

S

[vinny]

That sounds perfect but I don't know how I would pick them up. I'm in MS

Vinny

[vinny]

I just figured on the trip to Colorado for the two engines and Sh!t! It would cost me about $400 in fuel alone coming from MS