Hello, I'm looking for opinions.

CAR: 68 442 W30, 4 speed, 400 G block, D heads with a 4 speed, all stock.

Just return from the machine shop and everything checks out on my heads, block and crank. They honed the block and everything looks good, just as he thought he can reuse the .30 oversize pistons, just need some new rings. We talked about the compression ratio again, we both decided we should do more research on the subject before we go any further, he said he would look up the W30 cam spec and see if that will work with these 10:5/1 compression pistons with todays low octane fuel. So I'm to do my research as well, so here I'm am.

Ok, finally to my question to you: Your thoughts, running these high compression pistons, W30 cam, stock carb distributor, stock everything with today fuel, is this gonna be a problem?

Thanks so much guys. I haven't been on here for awhile, took about a two year sabbatical from the car, so I'm back on it.

 

Before you assume that you really do have 10.5:1, you'll need to know your deck height, cylinder cc, piston cc, and gasket cc.
Once you do that and know how much you really have, then we can go from there. Again don't assume.

 

Very good point and thank you. I believe my builder has done that, he showed me on a piece of paper with a calculation of 10.62.

 

Get rid of the W-30 cam, there is a ton of potential in a modern grind. Once again, figure the exact compression before discussing camshafts.

 

To be honest, I’d like to see those calculations. How would he know what the deck height is already without assembling it? Hmmmm

 

Just to clarify what needs to be done is:

Reassemble the block, this will give the deck height, then cc the piston, then cc the head and gasket, this will give the exact data to figure out what the compression ratio will be.

After that, then you can pick out the cam to match?
What happens if the compression is still high, even after the head work.

 

 

Polishing combustion chambers is an option. What octane is the premium in your area?

 

92 and I was planning on running non-ethanal.

 

Maybe I should have approached this thread a little differently". So, the car is a frame off restoration, I don't plan to race it, nor daily driver, mostly a few cars shows and a occasional trip on a warm summer day to the local drive-in. (So honestly, I don't drive the cars enough). With that in mind, I want it to drive, run, sound like a W30. What the inside of the engine has in it to get there, I don't really care, just need it not to ping.

I talked to the builder and he clarified, his paper was basically guess work based off stock info and that he just wants me to be aware that I could run into high compression using these flat top pistons. He said we wouldn't really know until we go down the road as Cutlassefi has described.

I sure appreciate the feed back guys, when it comes to paint and body I can hold my own, get inside the motor, well...post pretty well sum's it up. Thanks

 

 

If you are not driving the car that much, why is higher octane fuel not a option ?