Pressure plate bolts for FieroRog 3800sc flywheel (Page 1/1)
GodSend OCT 25, 11:05 AM
Hi Guys,

Thought I would check with the Gurus here. I've reached out to FieroRog via facebook several times (he has responded) but im not getting the info I need for some reason.

I have my flywheel mounted up, and according to all the guides GM Part "24571667" is what I should be using. I bought those bolts (they aint cheap) and the absolutely do NOT thread in (more than a thread or two). The 3800sc swap group on facebook is giving me all kinds of suggestions, but nothing has worked so far. ARP 651-0750 was also suggested to me, which is a 5/16-18RH thread. Picked up a few generic bolts just to test, and sure enough, no dice.


I even went as far as buying a "26 piece bolt thread checker", none of them fit. I did confirm the 24571667 bolts do fit my old fiero flywheel from the 2.8 (should they be the same bolts fiero stock and fierorog?)


Its possible the threads are ALL messed? I dont mind chasing them with a TAP, but I need to know what they are supposed to be. I even went as far as asking FieroRog "Is this a Camero flywheel" after I coulden't get an answer on the specific part number so I can simply confirm absolutely what bolts I should be using. Seems like a basic question.

IMSA GT OCT 25, 12:36 PM
This was from another thread. I don't know if it helps.

quote
Originally posted by slideways:


Keep forgetting to measure the extras I have in the shop, I'll get back to you.

But I can tell you the FW - Crank bolts were 5/16" - 18 Grade 8.2

FW - PP bolts were metric I used 12.9's and they were 1/4" longer than the ones from SPEC

Got them all from HD supply, the 5/16's were some kind of aviation grade at $6 a piece...



Also regarding the stock 2.8 flywheel.

quote
According to the P22:

Flywheel to crankshaft: M10 X 1.0 X 23 (10.9)

Pressure plate to flywheel: M8 X 1.25 X 22 (9.8)

where for example for the first bolt:
M = metric
10 = diameter in mm's
1.0 = thread pitch
23 = length under the head in mm's
10.9 = metric bolt grade

[This message has been edited by IMSA GT (edited 10-25-2023).]

IMSA GT OCT 25, 12:54 PM
.

[This message has been edited by IMSA GT (edited 10-25-2023).]

GodSend OCT 25, 04:35 PM

quote
Originally posted by IMSA GT:

This was from another thread. I don't know if it helps.




See, this is the weird part. GM 24571667 is indeed m8x1.25x21.6, 10.9 . Which as you show above fits the stock 2.8, but then I find threads like this

https://www.fiero.nl/forum/Forum2/HTML/134623.html

which references this build

https://www.fiero.nl/forum/...2/HTML/000156-4.html

If I am not mistaken that build uses a Camero flywheel machined down, which is what FIEROROG sells (I wish he would bloody confirm this with me).

SOoooooo... both the fiero and camero flywheels are supposed to use the same bolt? I mean I feel like I am takign crazy pills because the 3800sc facebook group jumped down my throat when I tried to clarify.

IMSA GT OCT 29, 05:47 PM
Just a bump to help you out.

We have so many people with 3800 motors and NO ONE can answer this?
cam-a-lot OCT 30, 06:02 AM
I used 2000 V6 Camaro flywheel (not pressure plate) bolts and they worked fine. I think maybe you just need to de-burr the holes and try again? Make sure you pay attention to the correct torque settings. Darth Fiero (Ryan) has posted the correct info a number of times.