And I didn't say that either. I said on some motors they might not pick up swapping out a 4150. On a heavier car without a lot of motor, 4150 might well ET better.My old 422 W5 motor being an example. That said I took off a 1025 race a Demon rs, and I didn't lose by the swap, just didn't gain anything. Depends on the intake as well, a dominator flanged intake has definate advantages. My 422 intake I used an adapter, probably part of the equation no doubt. The 1025 wasnight and day better on the street. I was an idiot getting rid of it to gain nothing and suffer in drive ability.
Patrick at pro systems is a friend of mine. He loaned me a 750 4150 carb, and a 1000 cfm 4150 carb. Tried both those, the 1100 dominator and the 1025 race demon. The 750 only ran about 13 hundreds worse than the Dom and race demon.
Bigger isn't always better. My little 318 was dyno'ed at engine masters with a 950 on it. It I am sure made the most power with it. I put a 750 on it the other night, and the car seemed noticeably quicker pretty much right out of the box.Have yet to verify the results at the track, but will soon

Here is pic of intake and adapter that Brett done on my motor.

i will try the carb spec sheet again.

That's a wacky tune up in my humble opinion.................What`s the emulsion set up?

Same exact carb I had. It's an 1100, not a 1050. Only difference is squirters sizes that I can see.

Thumper do you see anything that would cause me to loose 60ft? Or anybody else got any ideas.

1 tenth and 2 mile an hour WOW.this thread should be Pro System kicks butt. that's very impressive.I'd say try the timing thing.and talk to your converter people it might need to be loosened up a few. Rpm can help air speed down low dominators don't like slow Air speed.but like what was mentioned more timing would be my first test

I`d size down the squirters for starters and mess w/float level and emulsion sizing and maybe a t-slot jet and as others mentioned timing stall etc.

No 4500 experience, but I'd get timing squared away first.

Distributor locked out or have advance curve? Initial timing will have a large impact on idle characteristics, signal strength, etc. Need that set up before you mess with the carb or you will just end up chasing your tail.

Rich at the hit and rich at part throttle can be tuned with squirters, idle feed restriction and transfer slot, as Thump stated.

Would love to see your spec sheet posted up. I bet it is VERY similar to ALOT of others he does, regardless of the combo it was built for. Seen it many times before.

When I bought my Dommy it had 28 squirters thinking they were too small went 42 before I tried it picked up 1 tenth and 2 mph. but 60 was slower. next week after a couple tt's changed back to the 28 sqirters it came with and 60 foot cam back so was now .2 and 2 mph faster.
Guess guy who owned it before me had it right.

Put the timing in the motor, I went from 9.70s to 9.50s with 4° of timing. It will help 60 ft too.

Thanks, that sounds what I need to try. It has #40 squirters in it now.

Also I forgot to say that I FOOT BRAKE. I do not have a trans brake.

Why is it so hard to just add timing... I would start
at 2* per jump

The 1100 of Patrick's I had came armed with 45 squirters. Either off the foot or the brake the car 60 footed the same number( and if the car is sorted out that should be the case with most such bracket cars)
Don't think I ever tried smaller squirters, the 45's were just as crisp as could be. I have no idea why he uses such big squirters after getting all the combo information and then building a custom carb to suit that combo..... But they seem to be the norm.

I have the timing set exactly where it was when I had the 950 on it when I was having 1.33-1.34 60ft. times. I did not know that you had to change the timing when you changed the carb. I was just wondering why I lost 60ft. with the bigger carb. That was the only change. I lost at least 6 hundreds in the 60 ft. But I am here to learn something..

I dont know didilly but if the guy that built the
engine says jump the timing up... thats what I do

Pull timing! Less power more hook....? Idk anymore

I thought it would be better to figure out the carb problem before I started changing the timing. I guess I will try more timing next time to the track.

And you are right........If you lost 60ft, with the same timing you had before, the carb is NOT right. Yes timing may help it, but it would have likely helped before as well. Bigger carb, slower 60ft, equals that it is TOO RICH down low. Fix that, 60ft will come back

Monte