Rod length on Spec motor

[dirtdevil]

On a SUPR Spec motor is there any noticeable advantage/gain from a traditional 3.48 stroke w/ 6.00 rod compared to 3.50 stroke and 6.125 rod ?? What about 6.250 rod ??

[TBRE]

I hate to go against the "Holy Grail" of racing engine builders, but not every engine will benefit from a longer rod.
Matter of fact (no pun intended, but these are my personal findings), the only engine I have seen that benefited time after time, from a longer rod, was a "plate" engine.
A "SPEC" engine, "SUPR" engine, 2bl engine, all have restrictions built in them, but it is an uninterupted flow, unlike putting a plate on top of an engine capable of making much, much, more power, without it.
I've spent a lot of time on this, and hate to share to much, but you're going to figure it out anyway eventually.
What I gained on "dyno" with a 6.200 rod, I lost on the racetrack in performance. The 6" in not too long, and not too short. There, I just saved you thousands of bucks. Call Liz next time you need a good price on engine parts.
Have a Happy New Year.TB

[dirtdevil]

Thank you Mr. Barker. Your answer is what I was thinking.

[parrot69777]

It really all depends on what the driver prefers.