Does my 3.4 sound cammy?

[crzyone]

I recently installed a 94 3.4tdc into my fiero and it seems to sound quite different than other fiero's with a similar exhaust setup.

The owner of the motor said he got it off of a guy whose son wrecked the 94gtp in a street racing accident. They said they had done some performance modifications to the motor. Not sure but I thought maybe an exhaust cam retard?

Since you guys are the expert on this motor I thought I'd ask you. You can compare my engine to the other videos and sounds on the page.

Video of my car can be seen here:

http://www.fiero.nl/forum/Forum1/HTML/047008.html

And a build thread of my motor can be seen here:

http://www.fiero.nl/forum/Forum2/HTML/053341.html

Not sure how lopy a 3.4 is supposed to sound at idle with a cam retard but it does sound quite lopy.

Thanks for any answers!

[PlatinumZ34]

someone help him, i know alot of you have retarded exhaust timing... All i can tell you for sure is that doesn't sound stock.

[mopowr79]

Sometimes a total lack of knowledge might be helpful, so here goes. Do the DOHC motors use a CPS? If it is not getting the correct sensor information, then maybe it is running the timing retarded. Another option I noted was that when you fired the motor up, you said there was no O2 sensor, sometimes that can put the computer on limp home mode and will run the engine with a static set of ignition and fuel settings. Until recently, my major FI experience was with 4.0 Jeep motors, so its possible that noe of this trasfers over to GM DOHC tech, but I thought I would help is possible. mopowr79

[SappySE107]

If there is no O2 sensor, thats probably part of the problem. It doesn't sound too much different than mine, other than the note itself. Mine is tuned, 13 degree retard, ported heads, 2.5" mandrel bent exhaust with 1 40 series flowmaster. The way yours sounds though, the cam timing is not stock. Hard to say on any other mods without a dyno. I didnt read the thread on fiero.nl though but if the O2 isn't in there, that could be the only reason it sounds like that. The CPS is vital for the car to run, and it usually either works, or doesn't. I haven't seen one give bad info and still run the car.

[Mitch DOHC]

it sounds about like my cutlass.. and i also have the 13 degree retard

[crzyone]

Thanks guys, the O2 sensor has been installed, no change in sound. These motors sound pretty mean.

If these motors were 210 stock, how much more power can be expected from free flowing exhaust, intake and no power steering or a/c? Ive also heard the cam retard gives something like 25-30hp??

Thanks!

[SappySE107]

The power steering robs about 10 hp according to nico, who also ran his down the track with and without the power steering. I dunno what the cam timing really does so thats hard to say for sure without a dyno. intake and exhaust are worth a noticable amount as well, guessing at least 10 for both combined as well.

[Gemmer]

The AC wont make a difference.

[97montez34]

damn that sounds mean... kinda hollow sounding tho, but alot deeper then mine. i wish that cam timing thing would work or someone knew it would work for the 96+ DOHC's.. gotta do the timing belt soon and figure i might try it out, but thats alot of work if it doesnt run.

[SappySE107]

The cam specs were supposedly the same for 96, as far as duration and lift go. If that is the case, its just a matter of compensating for the cam flat position for your cams. With 2" primaries on your headers, you may as well give up on low end and tune it for all out top end. I am sure the 96 motors with their larger intake ports are pointless to tune for low end to begin with anyway.

[97montez34]

well the headers r probably going to be re-tuned down to 1 7/8" or smaller, it all depends on milzy... but your right, with the longer runners on the 96+ DOHC intakes, we have zero low-end to work with so its pointless to even try

[crzyone]

You guys should hear this thing at WOT at 4000-7200rpm :drool: It just screams and pulls like a freight train. I recomend this engine in a fiero, this thing is crazy! 60-100mph in 3rd gear goes by so quickly, way to easy to get your licence taken away

[Gemmer]

with the longer runners on the 96+ DOHC intakes

shorter?

[SappySE107]

I heard it was shorter. They are definetly larger, which hurts low RPM velocity.