R-1 Compression

[J Boyle]

As part of my cars restoration I'm having the engine looked at.

And a rebuild might be in order.

The engine rebuilder I'm working with said in light of today's lousy unleaded gas, that I consider possibly lowering the compression ratio down to 9.5. He said it would help theengine in the long run...but he also said that if the basic design is strong enough, it may not be necessary.

My car is an R-1 with AC and auto, so I'm not going racing anytime soon...Bonneville and Strictly Stock drags are not in my plans.

So I doubt if I'd notice it.

Any opinions are welcome.

Also, can anyone recommend a vendor who sells rebuild kits...I don't want NAPA generic stuff.

Also, it looks like a need a new harmonic balancer...any suggestions for that?

Thanks...

[Gunslinger]

The stock compression for an R1 is 10.25:1. As long as you have the heads redone with hardened valve seats and keep the engine in tune, you should have no problems with todays gasoline. While I don't know how much of an issue this could possibly be, with the ethanol mixed in today's fuels, I understand it may not be all that compatible with the internal seals of the carburetor and flexible fuel lines from older cars. I can't say I have personal knowledge of anyone having such a problem, but it is supposed to be something to watch out for.

Even without hardened valve seats, most drivers of older cars have little if any problems with todays gas besides harder starting after the car has been sitting. That's due to fuel being reformulated today...it's not an issue for fuel injected vehicles, but carbureted cars experience it. Just something that has to be lived with. If your car has lived for over thirty years of only unleaded fuels being available, do you think it won't make it for another thirty years after a rebuild to the same stock specs using the same fuels?

BTW - there's nothing wrong with NAPA parts. They get their stuff from quality suppliers. There are a number of vendors listed through Turning Wheels and the AOAI magazine for most any part you want. Once you have your engine torn down and mic'd, you may find out all your cylinders are still within factory specs and don't need to be overbored...simply honed out. That way you wouldn't need new pistons...a big savings. The Stude block is quite hard and can take a lot of abuse. The '63 R1 I used to own was rebuilt at 100k miles...still within specs so a new set of rings was installed after honing with all new bearings. Most of the parts were sourced through NAPA.

Edited January 15, 2009 by Gunslinger