My homemade ring compresser
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by jackson
Stock sbc 400 bore = 4.125". FYI ... compared to thirty over pistons, there are relatively fewer offerings in twenty over ... MANY desirable shelf-stock sbc 400 pistons are not available in twenty over. Suggest do NOT assume that all pistons are available in twenty over ... but do your homework & all planning before you jump in.
Thanks for the info, but I have already had the motor back from the machine shop. Bored +.020 and decked. I then found and ordered a set of +.020 SpeedPro coated pistons. I then had them throw in the correct rings for a package purchase.
So a 400 being a stock bore of 4.125, I add .20, and need a compressor with a final bore of close to 4.145?
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Originally Posted by Durango_boy
Thanks for the info, but I have already had the motor back from the machine shop. Bored +.020 and decked. I then found and ordered a set of +.020 SpeedPro coated pistons. I then had them throw in the correct rings for a package purchase.
So a 400 being a stock bore of 4.125, I add .20, and need a compressor with a final bore of close to 4.145?
So a 400 being a stock bore of 4.125, I add .20, and need a compressor with a final bore of close to 4.145?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by jackson
Yes. Purely a guess ... SP pistons either H615CP20 or H616CP20? Next time ... best to bore-hone block with pistons in-hand ... honed to fit individual piston. Same goes for rings ... hone/finish/grit/Ra to mfg's specific ring guideline.
That was the original plan. I had dropped off the block to be bored +.030, and when I picked it up, the invoice said +.020. A called and asked what was up, and the machinist said they don't like to take more than is needed and the walls only needed that over-bore to be good again. Yes, I got a FULL refund, and then just decided to keep it the way it was.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Originally Posted by Hvymtlc5
Beats a tin can and hose clamps.
What's wrong with tin cans? Beer cans are close enough. Somewhere I have this cool pic of an engine with an intake that had 8 tubes, six inches long, going straight up. I can't recall what that kind of old intake is called. Anyway, he had bottomlesss beer cans over the tubes, I guess to keep any rain or dirt from getting down into the intake.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
