I knew some reference to my 4.10s being "race equipment" would be made making it higher rpm. That's only roughly 10% more gear than 3.73s what ALOT of "street" guys run. They are still in the car from the 400 and roller motor. The car has seen only 2 outings and 7 runs since the new motor. The 3.42 are in the garage to be put back in when I get the time, and the A/C. From the feel of the car I doubt it will suddenly become a "PIG" and have no low end off idle power. The motor makes over 410 ftlbs @ 2100rpm! To even get the dyno load to read low rpm we couldn't do full pull. It can easily haze the street tires in first or second, so the decreased torque multiplication will improve that. Do I really need more torque at 1500, especially with a convertor that goes past that quickly. Maybe if you have a TKO stick and leave in in high gear, but that's why God gave you a gear shift.I've ridden/driven in alot of different combinations(including Jim's wagon) and know the feel of bottom end and throttle response.
By the way let's look at the rest of the pump gas "race" combo that just clicked off 10.99 @ 124.5 and drives 40 miles to car shows. 0.030 455 no stroker crank or long rods. A 239/247 flat tappet hydraulic (5 degrees bigger than Jim's) Jim's is a little bigger than Cliffs, the same on Floyd Hand used for awhile.Torker II that many feel is worse than a RPM or cast iron(Shaker hood) out of the box Holley 850(Cliff runs the same or slower with a massaged one) with a 2.75x13.5 air cleaner and Shaker base. 10" Hand convertor -out of the box-same as Cliff, Jim and Floyd and many others here.Headers 3" full exhaust with mufflers and tailpipes. Ported Eheads-has to be a race car high rpm no bottom end.
You missed my point Cliff did back to back with similar cam specs and ran faster(yes I know Cliff's combo) with the BIG heads. The extra weight of the hydraulic rollers could even be a potential detriment. He's said the car is at least as responsive as before. TCSGTO in the street section ran faster with out of the box E heads over ported D ports. Several others ran faster still in streetable range. I've always contended MOST of our street/strip Pontiacs can use more airflow and still have so much bottom end torque you won't notice. I think most of these guys are showing that.
example a stage 2 ported cast iron head flows in 240cfm will be so much crispier-razor sharp bottom end over a 310 cfm head., "AGAIN only low speed part throtle drivability" . Look at the bottom end number off the Kasse motor from last years Engine Master with the HUGE Tiger heads more bottom end than my motor! Tell me that motor didn't have a crisp bottom end and it was all over by 6500.
The variables of the different port shapes, chamber shapes don't make an apples to apples on just port ccs. A 6X-4 head has a smaller diameter chamber than a 6X-8 head why they are 93cc vs 98cc. That has to affect flow into the cylnder , quench slightly differently even if the port is the exact same. A 62 head has the same shape chamber but much shallower (.200) so even different flow into the cylinder, and has a different shape port than the 6X in the intake and exhaust floor. The we have the RAIV, and HO/SD "open Chamber shape" that os totally different. We'll leave the RAV out with its different chamber not too many to comapre with. We are stil talking iron heads with many variables (enough Pete Mcarthy had numerous articles documenting) and haven't even gotten to the different port shapes or chamber shapes of a aftermarket head.
So how can we say we are just looking at larger ports? I think that is being way too simplistic. Unless Cliff throws on some ported larger KRE heads or Jim had tested his 6X before his meticulous porting to spare ccs(something not done in most commercial porting jobs) we are not just looking at ccs we have other variables at play so no way its apples to apples. And as I stated before how do we know that a smaller poorer shaped port will have better overall velocity and cylinder filling than a slightly larger better shaped port? I still have a problem believing in a RUNNING engine we don't see high velocity in a port the size many FACTORY first gen SBC use(Vortecs) with 100+ CI more to suck on them, especially with the piston speed a 4.21 or 4.25 stroke puts on the port. The same way a Superflow 600 with more motors can flow more velocity test pressure on the same hole compared to a smaller (fewer motors) 110 Superflow. It can barely pull the cfm at 10" in a moderate head compared to 28" on the big bench on a big head.
In being around some chassis dynos a loose convertor almost negates an accurate torque number. So I don't think Ron's numbers would clarify that unless he has engine dyno numbers.
Those Crower rocker numbers 1.33 break ins 72885
stainless 0.090 offset trunnions 1.8-73689, 1.75 73688, 1.7 73687
aluminum offset trunnion 1.7 72897
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