Inliners International Forums General Discussion Hi Performance Dyno day for a 292, Need help

I am back, after a very long dyno day.
Much has been learned about this motor and some of the different theories out there have been put to test.
offy vs clifford vs PES
stock head thru big valve lump head tests (4 of them)
5 cam tests
even the ole 194 cu in high compression head test

The dynoing is not complete, today did not go as well as yesterday, and maybe yesterday went way better than we deserved.

We chased a bug after a cam change that could not be shook. So not all tests were run , yet. The engine is staying on the dyno for a bit longer, will try to wring out the bug.

Here is the bug.
Head presently: 194 with 1.94 intakes / 1.60 exh. ported and lumped.
cam Clifford 270
Intake Clifford
carb 600 holly
When making the run torq starts nice and is higher than most other runs. About 3600 rpm it seems to have a dip and then pulls again, at higher rpm, there is a definate cough/ hiccup around 4600-4900 rpm. AFR looks good and simular to other runs. Did same thing with another head but was more prevalent. We found a galled exhaust valve and thought we cured it(with other head). This week will try a different dist. If that fails then change the cam, since this is when it started, even with other head.

So far the highest Hp seen was 275, but we are sure that this cam will surely produce 5 hp more. tq with this cam stays above 300 from 2500 - 4600 rpm. but the hiccup kills the dyno run.

I will get the info compiled and let you know more about the specific tests.

I can say this without a doubt, The Clifford manifold wins hands down over a Offy in tq from 2500 rpm Up. And this is where we tested.
Also tested was a PES intake. We could not even get a full pull from it! It must send the worst vacum signal ever to the carb. I even tried to hold the secondaries closed and open to get it to work. Bad science there for us. That was also the start of problems for us on Sunday.

A big thankyou to the local( 2 hr drive ) guy's. They were a huge help. And big thankyou to Tom Langdon and Elmer Stange that drove 8 Hrs to help for 2 days. That is dedication! Dave Jones was a big help on Saturday and kept all the tools and parts going the right way.

I finally succombed to those blasted headers with a intake swap. Got a Rasberry burn on my forearm. Got alot of complaints of the shine in the camera images, what are they talking about? And that Joe Gibbs Racing oil is going to stay in my hands for a week! On the drive home in the Elco, Spilled the crock pot of baked beans in the bed, tried to get the dog to eat them and he thumbed his nose. Guess I will have to clean it up.