Lets say someone was putting a Shortstar in his Fiero. And that person was also using a Getrag trans. What flywheel and clutch should fit? It stands to reason that since the 3.5TDC and the 3800SC both bolt to a 4t65, and people use getrags on 3800SCs, the same flywheel and clutch setup should work. -Matt BTW, what flywheel are you Manual 3800sc people using?
IP: Logged
05:15 PM
PFF
System Bot
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
I have a crate motor 3.5 on the floor so I will check it out. I have thought about this before but never got around to cheking it out. I did bolt the 3.5 to a 5 speed Getrag just to see how it looks. It will bolt right up to it. the problem may be the offset of the flywheel and crank flang. I have a flex plate from a 3800SC and a custom flywheel (modified 3800 Firebird) which is what some people use on 3800 conversions. I will take some pics and find someone that can post them for you to see.
IP: Logged
09:35 PM
DakotaMatt Member
Posts: 144 From: Macomb, MI, USA Registered: Oct 2002
Well I am not doing a 5 speed............Yet I need to get the auto to pass smog in CA. first, then change it over to a 5 speed. After it is all legal "auto" and the bugs are worked out, I plan to swap it over. I know I cant get it certified as a stick, but I may be able to just get the simple 2 year smogs, if they dont look close? Also doing the auto to manual swap after the system was debugged, will narrow the field of potential bugs. IE, Is the problem in the wireing or in the PCM? If the problem is in the wireing the stock engine/tranny drivetrain wont work. But if it does work and runs great, then switch to a stick and it dont run so good anymore then I will know the problem is in the auto/stick conversion not in the Olds/Fiero conversion.
IP: Logged
12:41 AM
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
I just looked at the 3.5 flex plate, it has a bolt circle that is MUCH larger than the 3800. So I will have to get a different flywheel. I guess that it is the same flywheel as the N*?
IP: Logged
01:12 PM
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
This is a pic of the 3.5 and 3800 flexplate side by side. The 3800 is externaly balanced and the 3.5 is not. Also the hub-centric hole on the 3.5 is much smaller than the 3800. And if you look close you can see the differance between the two bolt circles.
IP: Logged
03:13 PM
sspeedstreet Member
Posts: 2306 From: Santa Maria, CA Registered: Dec 2002
Mostly plugged and redrilled stock flywheels, however KF Group now makes an aluminum flywheel for the Northstar.
------------------ '87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc. '90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow
IP: Logged
09:18 PM
PFF
System Bot
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002