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Discussion Starter #1
Hey guys,

So my car is a 91 L98 bone stock and want to replace the timing chain and sprockets since they have been there since it was made probably...
The issue is I bought a kit at O`Reillys that reads 1955 and up chevy small block, but it turns out the sprocket on the Camshaft does not fit since screw holes are not at the same distance.
I have heard the single pin kit that was on the car is supposed to be worse in terms of performance since was developed for emissions purposes...?????
And that the double roller will not only make it run better for being new but better performance since it wasnt designed for emissions... ?????

Anyone bump into this?? All I want is a double roller that fits my car and CC shows they have it but not sure if it will fit my camshaft...

http://www.parts123.com/parts123/yb.dll?parta~showpic~Z5Z5Z50000050f~Z5Z5Z5FAYEU~Z5Z5Z5~Z5Z5Z5~Z5Z5Z5

or this one??

http://www.parts123.com/parts123/yb.dll?parta~showpic~Z5Z5Z50000050f~Z5Z5Z5FAXMC~Z5Z5Z5~Z5Z5Z5~Z5Z5Z5
 

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I'm not a fan of the second choice chain. It is a butt link and not a roller. It does great for longevity on a budget and that is it's design. I prefer single roller for the least friction issue and the best I've ever used is the Cloyes 3157. Big ole' 1/4"
rollers and very heavy duty. Never seen one even get loose and I've built an engine or two.
 

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i also used the Cloyes True-Roller on my 1990 L98 (factory hyd roller cam block).

i think the part number is 9-3145.
 

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Discussion Starter #5
Thanks guys,

I ended up ordering the first option that I posted above since they give me the best deal shipping it to Spain... I hope it works... and it seems to be OK for a stock engine.

The factory single pin I pulled out of the car was completly loose and it was causing the car to run awfull since the cam is about 4 degrees off.
I was having to correct that by setting base timing at 12 instead of 6 and it therefor not a good idle and could hear that chain making noise if I tryed to lower idle speed.

So hopefully this will fix it...

Thanks again!
 

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Discussion Starter #6
OK, so ordering from CC didnt fix it since they sent what I already had and doesnt fit my car.

The timing chain kit they sent as a 91 has the same Cam sproket I had... with the screw holes too far apart on the Cam sporket.

The problem is online I cant seem to even find one that looks like the one I pulled out of the car, sonce on the Cam sproket the center hole is not completly round ( has a flat section).
And the screw holes are much closer toghether than what seems to be the standard cam sproket.

Does that mean I can only mount a butt link kit on my car and that the Cam that my car has is diferent or form a diferent year model???:huh:

Thanks!
 

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can you post a clear picture of the cam and sprocket thats currently in the car, theres a chance that youve had a previous owner swap components with a different gen sbc
 

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Discussion Starter #8
Grumpyvette,

I hope to get sometime off soon and be able to take those pictures and see iff we can figure this out. I mean the car has a timing kit on it, its just old, chain is way too long and its that but link kind...

Will post pics ASAP!!

Thanks!
 

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Discussion Starter #9
Here is the picture of the problem,

The one with the blck piece of tape came out of the car and the one in red tape is what i have been sent twice. But notice how much bigger the center hole and how much further apart they are.

I cant seem to find a cam sprocket thats equal to mine...
This was taken off a bone stock 91 in Spain where people just dont change cams in american cars cause there arent many of these and cero aftermarket parts or performance...
 

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here's what I think your replacement timing chain is supposed to look like, this is a Cloyes 9-3145.

you can see on the Cloyes below, the big sprocket is machined to clear the cam thrust retainer plate bolts, and the three bolts holes are at the edge of the register step.

I'm suspecting that somebody did change out your timing chain, but because they couldn't find the right one, they used something "close". the one with the black tape: kinda puzzled by the small hole, looks like that was for the LT1 water pump drive (or is it the LT1 Optispark distributor drive)? I'm not familiar with LT1's. mebbe that's all they could get ahold of, and it fit, so voila. is the previous owners' name "Bubba"?

in your picture, the timing chain kit with the RED tape looks like the SBC kit for non-factory-roller cams, i.e. SBC 55-86? can't remember when the factory hydraulic rollers first started, either 87 or 88...



 
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