Just curious if anyone here knows. I'm searching for a 1pc rear main 2bolt 350 block for a rebuild. I have a 2pc, but since I'll be using a f-body 6 spd, I'd rather save the $$$ than spend it on the centerforce flywheel needed.

Anyone know for sure?

 

GM went to the one peice rear main in 86 I think. THen went to centerbolt valvecovers in 87.

 

thanks. that will help me in my search!

 

However remember that no Camaros were produced with a 350 in 86, they were all 305s. SO if someone tells you they have an 86 f-body with a 350 they either have a swap or they are lying. GM didnt put 350s back in them till 87

 

Well, I wont be looking for a whole car - just a shortblock. With the heads off, I should think I can ID the 350 vs. the 305. Thanks for the advice though!

 

Yeah Im pretty sure all of teh one peice rear-main seal blocks have 305 or 350 just stamped clearly on them. No looking up numbers on Mortec

 

87 for both (centerbolt and 1 peice RMS)

 

ive been under the impression that it has been 1 piece since 87. same time they swithched to the roller cam

 

Wrong! Their were Iroc-z's produced in 86 with the 350, however, only 74 were made.

 

I believe there were some engines produced in 1986 that had the one-piece rear main but still used flat tappet cams. 1987 they definitely had both the one piece rear main and roller cams.

 

Dude the L98 wasnt avaiable to the public untill 87...theres no 2 ways about it,...everyone and there brother knows someone with a 86 roc with a 350...BTW the "real number" was 50 not 74...None were sold to the public, IF there were any built they were used as mules then destroyed...and theres no proof they were even built...why dont you look up WILLIE on here and thirdgen.org..

go to www.gtasourcepage.com....www.thirdgen.org...

1987 was the year the 1 peice RMS and centerbolt heads started production...

 

:Corey gives you a round of applause:

The guy needed to know what year block to look for.

1987+ buddy - Hydraulic Roller, 1 Pc. RMS, Centerbolt

 

yeah, 87 was the roller block, centerbolt headed 350 with 1 peice rear main. But Im 99% sure that the 86 305s were 1 peice rear main too.

 

I've always seen the Car V8's had a one-pc seal in '86, but trucks had either or. It's confusing b/c of all the replacement engines with 2-pc'ers and production engines with 1-pc'ers floating around together. A lot of warantee replacments etc..

 

In 1986, Chevy started with the 1 piece rear main seal, but left the standard 4 bolt flange valve covers and the flat tappet cam in the motors. In 1987 GM changed to the centerbolt valve covers and roller cam. I spent many years working at parts stores selling replacement motors (and taking cores back), working on F-bodies and then did a few years at Jegs in tech support (for anyone who wonders who I am and how would I know). However, the 1986 block castings are not setup for the roller cam. So, you may want to consider a 1987 and up block to save money on the roller bits.

I've seen a few truck blocks with the "bosses" and the deep lifter bores for the roller cam, but the bosses weren't tapped and it didn't seem to be worth the effort to tap them for the conversion.

Hope this helps.

Good luck!

(I miss my 3rd gen....I keep thinking of selling the new Z-28 and buying another 88 or 89 Formula.....)