Are all late 60's/early 70's small block distributors interchangeable (sans LT1)? In other words, will a '73 or a '69 distributor perform in an acceptable manner in a '70? What other year distributors will work in a 1970 350/300 and yield the same performance? What are the differences say between a 1970 300 horse distributor and a 1970 350 horse distributor, or between a say a '72 200 horse distributor and my '70 300 horse unit? I have to believe all the internals are the same. Is it just the vacuum advance unit that's different?

 

I think all the small and big block distributors (other than transistor ingintion) from the late 60's to 74 will interchange. To take full advange of each engine the springs on the mechanical advance can be changed. Also you can get an adjustable vacuum advance if you feel you need to.

 

:iagree:
you should look at lars' timing paper on the corvettefaq site, it will tell you a lot about the differences in mechanical and vacuum advance between different distributors, it's more than just springs. joe

 

I am nearly 100% certain that the tach drive distributors in all 62 through 74 Corvettes, both Big Block and Small Block are virtually interchangeable. There are some variations, for TI ignition, Hi-Performance Engines and F.I. engines. Even though they are slightly different, they are still basically interchangeable.

 

Joe......how about a link to that site of lars'?
Thanks.

 

http://www.corvettefaq.com

Or send an email to Lars at V8FastCars@msn.com and request a specific article from him. Here's a list of the ones he has available at this time.


How to Rebuild your Alternator, Rev. A
How to Replace your C4 Front Brakes, Rev. A
How to Install your Distributor, Rev. A
How to Upgrade your C4 Driving Lights, Rev. B
How to Build a Fuel Line, Rev. C
HEI Ignition System Primers, Rev. New
How to Tune Your Holley, Rev. A
How to Tune Your BG Speed Demon, Rev. New
How to Adjust a Q-Jet Adjustable Power Piston, Rev. B
How to Set Your Ignition Timing, Rev. B
Handy Paint Mixing Formulas for Restorers, Rev. A
Corvette Body & Paint Basics (applicable to steel cars, too), Rev. C
How to Tune a Q-Jet, Rev. J
Q-Jet Problems I Have Seen, Rev. C
How to remove & Clean your C4 Radiator, Rev. C
How to Repair Rubber Bumpers, Rev. A
How to Replace Your Timing Chain (C4 specific, but applicable to any Chevy), Rev. B
How to Determine Top Dead Center, Rev. New
How to Adjust Your TPS and Idle Speed, Early C4, Rev. A
How to Refinish & Repair Interior Plastic Pieces, Rev. New
Vacuum Advance Control Units Facts and Specs, Rev. B
How to Adjust Your Hydraulic Lifters, Rev. A
How to Rebuild your Front End (C2 & C3), Rev. New
Engine Vacuum Explained, Rev. New
How to Set Up Corvette IRS Rear Camber (basic do-at-home version), Rev. A

 

All small block distributors will fully interchange. Big block distributors will also interchange with the small blocks with the exception of 348/409.

 

I found a little more info about HEI distributors that might interest some people. I think a lot of it generally pertains to the points ones, but the details will differ. Bottom line is aftermarket advance kits stink. Joe

changing hei mech adv
http://www.boyleworks.com/ta400/psp/distcurve.html

measurements of aftermarket kits
http://www.classicalpontiac.com/qa7/...i?number=49030