Hey all, My friend and I built a motor for his 1970 Chevy C10, but are really disappointed with the bottom end power this motor has, especially since its supposed to be a street/strip setup, it doesn't even spin the tires from a dead stop and we are starting to think it is because he is running a Victor Jr. and that it is too much for his set up, we are now deciding if we should switch to an Air Gap or Performer RPM, and thats why i'm posting this to see if you guys could help. His motor specs are as follows:
355 c.i.
9.5 C.R.
2.02/1.60 heads from Aero Head
234/244 @ .050 with .488/.510 lift cam
Victor Jr. (bogs at low RPM, but pulls hard after 3000 RPM)
Holley 750 Double Pumper
2500 Stall converter (soon to be on)
3.73 Gears and Posi (soon to be on)
Help Guys we want to be able to light up the tires from a dead stop, what should we do?!?!
Any help and advice would be greatly appreciated.
-Thank You,
-Cyrus '72 Chevelle
'76 BMW 2002

i would definately be using a dual plane intake either the rpm or the air-gap, but most of your problem is going to be with convertor and gears. it needs at least a 3.73 gear and a 3000 stall, IMO. if it's not driven on the street a whole lot, then i'd go with a 4.10 gear and a 3500 convertor. what convertor and gears does it have now? i think they are probably more of a problem than the victor jr intake. that cam probably won't make any torque until at least 3000rpms.

RPM air gap, my sons truck has 4.11's with your same stall and less cam with vortec heads and 10-1 compression,,,it will light em up and runs 13.50's all day

Very true, it makes power past 3000, and thats what i keep telling him to change first, his stall and gears since they are stock. He has the parts sitting in his room and he's going to install them soon. The 3.73 gears and Posi that i mentioned in the original post. I told him to go with a 2800 or 3000 stall but he bought a 2500 stall on ebay for $50, so thats going in also. I think the Air Gap would be better than the RPM, what about you guys?
Thank You,
-Cyrus '72 Chevelle
'76 BMW 2002

You should have never asked that...

He has is a problem.Too much weight for the torque of the little 350.

With 9.5:1 compression the cam choice is a bit off.He should have selected a cam with an intake duration of 221-225 degrees at .050. and a 108-110 LSA.It would also work great with the 2500 stall.

The 9.5:1 compression is to low with the cam to get top torque out of it.He should have about 10.5:1 with that cam.Also a cam with a LSA (Lobe Seperation Angle) of 108 would help produce low end torque for a better launch.A cam with a LSA of 112 or more should be avoided.

Those spec's sure look like the Performer RPM/Speed-Pro/Summit cam.If it is there is something you should know about it.
It is lazy and it lacks bottom end, as such a cam change is in order.

A 10inch 3200-3500 stall should be used to get the 350 up "On the cam".When it is on the cam it will produce good strong torque.It will work with a 2500 stall,but it is not a good situation for the weight though.
I know you and he are probably thinking that a 3500 stall speed on the street is crazy.That is not so.If you get a good converter such as an ATI Street Master they are very easy on the street.ATI is having their Fall/Winter sale.Go to their web site and look at their advertised price,take about 150 bucks off because of the sale.
THE CONVERTER IS NOT A COMPONENT TO SAVE MONEY ON!!!
As they say "It will make you or it will break you".
http://www.atiperformanceproducts.com/products/tc/smtcprices.htm

The rpm torque range with the cam and the 350 is just at too low of an rpm range for a Victor JR to be any good.If he had a 4000 stall it might be OK.A hi rise dual plane should be used.

1 5/8 headers should also be used for torque.