retarding cam timing on 307

[olds307owner]

hey everyone, my 1985 delta 88 has a vin y 307 that is 180,000 miles old so I was considering replacing the timing chain with a double roller. Upon doing a little research I read an article that said if you have a small cam like the one on the vin y 307 you can retard the cam timing 2 degrees and the engine will think it has a bigger cam thus you will get a little more power. Is this true? Also what chains would you recommend (edelbrock, cloyes, comp cams?)?

[88 coupe]

Originally Posted by olds307owner

........ I was considering replacing the timing chain with a double roller ........

You didn't say why. If it ain't broke, don't waste your money.

........ you can retard the cam timing 2 degrees and the engine will think it has a bigger cam ........

It will move the power band slightly higher. You probably would not see a measurable power gain.

........ Also what chains would you recommend ........

Any OEM quality replacement.

Norm

[olds307owner]

You didn't say why. If it ain't broke, don't waste your money.

I am replacing it because I have the money and I believe that in 180,00 miles there's some timing chain stretch already, and I have run it a few times without oil accidentally

Any OEM quality replacement.

I dont know but Ive heard that olds oem chains have a plastic gear, isnt this bad. Also, wouldnt a double roller be more reliable.

[88 coupe]

Originally Posted by olds307owner

........ because I have the money ........

If you waste it on a useless project, you will be that much farther away from having your 350 completed.

........ and I believe that in 180,00 miles there's some timing chain stretch already ........

OK, and some stretch occurred by 18 miles. How does your mileage show yours needs to be changed?

Do you know, for sure, it's the original chain? If it is, it will have stretched enough to give you part of that 2° cam retard you originally asked about.

........ I have run it a few times without oil ........

For what reason?

If the main/rod bearings survived, the chain was not affected.

........ oem chains have a plastic gear ........

Doubtful if "OEM" is still available. You can find "OEM quality" parts, at your local automotive machine shop or auto parts supplier.

........ wouldn't a double roller be more reliable.

Depends on your definition of reliable. Either should outlive a rebuilt engine.

As far as valve timing accuracy, the only way you can tell which is closer would be to degree the cam using both chain sets.

It's your car, and your money.

Norm

[olds307owner]

you will be that much farther away from having your 350 completed.

Well, I dont know if I said this before but even if I had the money for the 350 now I dont have plans on getting it until next May because right now its my daily driver and I dont want to affect my gas mileage too badly.

Do you know, for sure, it's the original chain? If it is, it will have stretched enough to give you part of that 2° cam retard you originally asked about.

Im sure my cars chain is oem because that car has only had me and my dad as owners. My dad told me he didnt change it when it was his so I guess it hasnt been changed yet. Thanks for telling me that thing of the timing chain stretch equaling to retarding it

For what reason?

I dont know why I was running it without oil. One time I noticed the oil pressure at 0 and checked the oil after having run around 25 miles and it didnt have oil. This also happened again a couple of weeks ago. Its pretty weird because there are no signs of oil leaks.

Thanks for your suggestion on telling me to not replace my chain I will consider something else

[joe_padavano]

Originally Posted by olds307owner

Thanks for your suggestion on telling me to not replace my chain I will consider something else

I've had the plastic cam gear come apart and toss the timing chain on an SBO with well under 180K miles. Fortunately the valves did not touch the pistons, so I was able to install a new chain and get the car running again. Personally I don't like to be stranded so I'll spend the money on preventative maintenance. If the car has a plastic cam gear I'll change the gear and chain at 80K - 100K miles. Usually the plastic teeth are getting worn by then.

For a different data point, I changed the chain in my Chevy truck at 150K and the factory single roller with metal gears was barely worn, but by the time you find that out, you might as well replace it. Again, for $50 I'd rather have the peace of mind.

The bottom line is that by 180K, I'd go ahead and put in a stock replacement chain (with metal cam gear, which is probably all you can get) and also replace the seal on the front cover (which is probably seeping by now). If the sealing surface on the balancer is worn, get a repair sleeve. And since you've already torn the front of the motor apart, you MIGHTASWELL put in a new water pump if this one has any age on it. Again, you don't have to, but personally I don't have the time to do this sort of thing twice. Your own personal free time and finances will dictate what you choose to do.

[88 coupe]

Originally Posted by olds307owner

........ Thanks for your suggestion on telling me to not replace my chain I will consider something else

Did I say that?

Norm

[olds307owner]

You didn't say why. If it ain't broke, don't waste your money.

If you waste it on a useless project, you will be that much farther away from having your 350 completed.

I dont know but from what you said thats the vibe I got.
By the way thanks joe. I too believe in preventative mainteneance if you can.

[88 coupe]

Originally Posted by olds307owner

I dont know but from what you said thats the vibe I got ........

Read it again. This time, in context and without adding any "vibes".

I'm done.