Wow! Thanks for all the info. I will have to read it a few times and try it out. I have 2.76 gears and at 50 MPH, I am at 2,000 RPM. I did notice the sag right around 10 inches. Before I read your message, I threw in a 5.0 PV from the 6.5 originally installed and it feels even better. Really pulls much harder. I reverified the transfer slot and I'm just over a square opening with the mixture screws out 1.75 turns. Thanks again for the good info.
This is not going to work;
Those 2.76s have got to go.You have way too much cam for those.And not enough tire.
Well it kindof depends on your stall, but here is the deal;
That cam has not yet vacuum-peaked at 2000, so you will be too deep into the throttle at 50 mph, and so yes, you will be on the mains, and sucking gas bigtime. Do not try to select a MJ your way, there is too much ugly stuff going on inside the intake, and the throttle will be too far open.
That cam wants at least 3.23s with high compression and a loose TC, and up to 3.91s with low compression and a tight TC. Typically it wants 3.55s with a 2800. Yes the Rs at 60 mph will go up, but the throttle opening will go down. And your tires are too short and they are probably gonna be way too skinny once this is sorted out.
Furthermore
If your screws are out 1.75, then the T-port sync is still off. Close them up to 1.0 and increase the transfer fuel by cranking in the curb-idle. Then back off the timing to get the idle speed down. Then adjust the idle air to make the engine happy.Then fine tune the idleAFR by tweaking the screws leaner from 1.0,or the transfer exposure, or the bypass air. You may have to try several different timings to give the engine what she wants.
If the 5.0PV charged harder than the 6.5, then the MJ is too big. Think about it. The 5.0 is slower to open than a 6.5, so you delayed the fuel delivery.And it ran better. So reduce the MJ size and try again, with the 6.5. Personally,I would try 68s and a PV in the 8.5 to 9.5 range This is just rearranging the curve, and leaning it out some, this is all gonna come out in the wash if you follow my outline in the earlier post, with the roll-in/roll-out procedure, looking for the sag.
But I'll tell you a secret;You can spend a bunch of time on this, and then when the 3.55s go in,you get to do it all over again.And if you swap out the TC,there might be some more changes.
If you insist on keeping the 2.76s, be advised that,that cam will buz you up to 65=6100......still in first gear. And if you still have the stock 73 teener TC which stalled at 1700ish with that old teener, now with the big cam, it may stall at a lessor rpm. So your car, while the motor is strong through the midrange, is gonna lose time at the start-line and suffer from low average power during the run,since it is a one gear run with small cubes. You may be embarrassed up to 35mph by a stock teener with 4.30s and if he has a small 4bbl,and a free-flowing exhaust, he may put a hurt on you all the way to 55/65;car for car.
I cannot imagine a good reason to keep the 2.76s with that cam, in North America. Well I can, but that would be kindof silly; Going hammer down at 45 mph, just above peak torque...... into first gear.Yeah she'll be quick from 45 to 65. You got money on that race? If no, the 2.76s gotta go.
Please, I built a combo like this once, a long time ago. It had great passing power, but man was it hard to get her up to speed.
My neighbor, in about 78 had a 71 Demon and asked me what was the quickest way to go fast with his teener. Four-tens I said. He hired me to set them up. You cannot imagine the smile on his face after the maiden voyage. He went on to other mods as time went by, but nothing compared to the day those 4.10s went in. Teeners and 4.10s are a match made in heaven. With your combo you have extended the operating range of your teener probably 1500 rpm. Your power peak is probably around 5400rpm, and she will hang on to at least 5800/6000. So if you wanted to max out the Rs at 65 mph, in second gear(1.45ratio) with 275/60-15s, you would need 4.88s, at least. You would need a traction aider and an LSD, cuz the starter gear of 11.96 would put "massive" amounts of torque into the axles, and they're not going to be able to hook on their own.Even with that stock TC, I can see 1600/1700ftlbs into the axles. With the 4.10s I see this reduced to about 1400 ftlbs. So with 4.10s I would suggest more TC, say a 2800 if you really wanna have fun. By 2800 your combo might be making 65% of peak torque, which might be 350 ftlbs, so 228ftlbs.(I'm guessing). And that would put 2300ftlbs into the axles. Now that's getting somewhere. What are you putting in now? I'll guess less than 850. So the 4.10s and the 2800TC will nearly triple the output into your rear axles. Can you say HANG-ON!
I did something like this to my winter motor back in the early 2000s. It was a totally hi-mileage 318 with a small TQ, some 360 valve springs shimmed up, and headers. Then I added the 4.30s, an A999 with a 2.74 low gear, and a 2800TC. Now a stock teener puts out its peak torque very low, right around 2800 or a little earlier. And it might make 320ftlbs. But lets say she was a lil tired and was down to 85%. With all that gearage she might still put down 3200 into the rear axles. I can tell you this much: that teener was the funnest combo I ever had.
Long story short, those 2.76s have got to go, and the stock TC too. Or else the cam, cuz it is sacrificing huge amounts of performance from idle to, what was it? 34mph did I say. I think so.
Ok got to go to bed now, I work tomorow.
