S2 oncenter question

[straycat990]

I was checking some measurements on my 153 block and came across one thing that made me go "hmmmmm". I was measuring the distance from the top of the front main bearing bore to the bottom of the cam bearing bore. The distance measured 2.0335; I compared that to the measurement I took off of a untouched (factory) 109 block. Which was 2.0235. So any one know why a S2 block would measure 0.010 more than a standard 109 block

Since my S2 block is .010 taller in that area .... I am guessing that I won't have to worry about having this block lined bored.

 

[TurboDave]

You got me wondering, so I went down and measured my blocks.

109 and BMS SII on center (aluminum).

They both measure 2.029"

 

[straycat990]

interesting Dave ... wonder if maybe my S2 block has never had a line bore or maybe it's bore was set up for gear drive timing set

 

[indyrich07]

now you got me wondering

I have one motor that came with gear drive,does that mean I can't put a roller timing chain back on it ?

 

[Big Stu]

Re: now you got me wondering

Originally posted by indyrich07
I have one motor that came with gear drive,does that mean I can't put a roller timing chain back on it ?

Out of curiousity, after having a gear drive, why would you switch back to a timing chain?

 

[TurboDave]

Re: Re: now you got me wondering

Originally posted by Big Stu
Out of curiousity, after having a gear drive, why would you switch back to a timing chain?

Probably because of the horrible reputation that gear drives have in the Turbo 6 motor.

 

[Big Stu]

Dave, where can I get that info? Maybe elaborate a little bit?

 

[TurboDave]

Just word of mouth stuff that I've heard around.

 

[indyrich07]

what I've heard

I was told by a couple of people,that on the buick motor the gear drive beats its self to death, I just think the roller chain is simpler and cheaper in the long run.

 

[opeltwinturbo]

I had a chat with Kent Rudbeck about timing chain vs. gear drive at BG right after my motor broke. He stated the gear drives tend to bind up under big power which could cause the keyways to break or the idler shaft to break. Timing chain is a little more forgiving at high HP.
I have been running gear drive for five years in the Opel motors without failure. Others have not been as fortunate. The new motor in the Riv is being built with a chain.
Good luck with whatever you select.

 

[BAGN]

Re: now you got me wondering

Originally posted by indyrich07
I have one motor that came with gear drive,does that mean I can't put a roller timing chain back on it ?

I had a friend who had a gear drive on his Stage II. The Cam bolt vibrated loose twice. (Loc-Tighted it both times) Still vibrated loose.
We put a Comp. Double Roller Timing Chain on it over 2 years ago & has had no problems since. (His Car makes over 950 H.P. @ the Rear Wheels & the timing chain works great.)

Hope this answers your question

 

[GARY HARVEY]

another reason...

Sides you can't run a gear drive with MR. Duttweilers oiler config.

Gary

 

[indyrich07]

hey Gary

Hey gary , I've bought parts off you long time ago