I am currently running the performer RPM. IN the past when I have been at the track we have experemnted with different carb spacers (1 inch 2 inch and 4 inch) and the bigger the spacer the faster she runs. I have seen .2 in crease in my 1/8 miles times just by adding the 4in spacer over the 1. This got me thinking that maby I should try the Victor Jr. because it has more plentium. How does that afect the performance if the engine? I know that single planes make more hp but have less torque and just the oppsite with duel planes like the RPM. Any ideas why I am getting the increase with the taller spacers? I have not seen any loss of torque with the spacers as I think my 60 ft's would have changed and they are a solid 1.8. THanks for your thoughts and Ideas

With a 2500 stall I would stay with the performer RPM. IMO you would loose too much TQ down low with the single plane intake. Depends on what cam you have too, but I don't see that in your sig.

The reason why it picked up is because your carb is too small :( , (try a 750 vac, 3310) and dual planes like bigger carbs. By adding spacers your making the plenum bigger and covering up the small carb deficiency.

eric68- THe stall I have is rated at 2500 but I can stall and hold it to 3000 and that is where I leave the line at. I know that single planes give up alot on the bottom end and I don't think I can spin this combo high enough to take advantage of the victor jr as my combo tops at 5500 and goes into valve float at 5700-5800.

67Rs502- I have thought for a while now that I needed to get a bigger carb but so many people keep telling me that with the mild setup I don't need it but the car runs way stronger than it should with what I got. I was wondering if you could explaine how the spacers compensate for the smaller carb? Is it possible that it is getting more air flow?? How?

Also I as asked about the cam... well i din't build this engine it came in the car when I bought it so I am not exactly sure.. at idle it has a nice lope to it and the power range is from 1500 - 5500. The car is still pulling untill the valves start to float. I think I need new springs. I would guess the cam to be in the 220* range

The cam may not be as mild as you think, and it just needs new springs,
since it floats 'em. What does your car run? 13s?
As for the small carb and spacers:
I'd stay with the RPM since you have a small engine and 3.55 gears.
The spacers just add plenum volume, which give each runner a larger volume
(space) to pull air from. (Most EFI intakes have a large plenum for this reason.)
The dual planes like larger carbs because they pull a better signal from the carb/booster,
and have a small plenums - so they still have good low end, and can use the extra CFM
to make more peak TQ and HP.
A single plane will also make more power with a bigger carb, but will have soggy
low end because of the weaker signal and bigger plenum.
A EFI system fixes this problem - since theres no fuel that needs to be pulled
from a booster, you can have a large (1000CFM) throttle body, a large plenum
and still have excellent off idle / low end throttle response.
Most people run carbs that are way too small (for peak TQ and HP) on the street.
(On the dyno I see 10-20HP and TQ just by switching to a larger carb.) Small is find
for a street motor which is just a cruiser - it will have good low end throttle response.

Here's 3 examples:
stock 307, performer/headers (68 chevelle) with 600 holley, ran 15.10s - swap to a
750 vac it ran 14.90s

406 w/750DP on the dyno = 430HP/485TQ, swap to 850DP = 440HP/500TQ.

Same 406 at track with 850DP = 12.20@111, swap to HP950 holley = 12.10@113

The 307:
3310 ~ 750 vac is a good all around carb for a mild street motor, it has good low end
throttle response, and since its a vac. secd. the engine only uses the CFM it needs.

The 406:
Most people will tell you a 850DP is too big for a mild street 406, but the dyno didnt.
99% of people will tell you a HP950 is waaaay too big for it, but the track didnt.
Why does the 950 work so well? They miss an important fact - the HP 950 uses a
750 body and an 850 base plate, giving it the throttle response of a 750CFM carb,
but the power of a big 950 CFM carb!
HP950 is the way to go on any serious street SB! - from mild like that 406, to a wild
solid roller, pump gas 406 in a buddy's Luv truck which runs 10.30@129.

Dare I say "bigger is better" - in most cases I do!
(on cams & headers stay reasonable)

67RS502- My car runs 8.70-8.55 in the 1/8 depending on wich spacer I am running. I have not been to a 1/4 since I have upgraded wo slicks and changed out the rear end but with thoes 1/8 mile times I am hopping for mid to low 13's. The only time that I raced 1/4 is when i had an open 10 bolt with 2.56 gears and I was using radials getting 60 ft times in the 2.4 range. Then I was running a 14.2 @ 103 and it pull hard to the end of the track. I now have a 12 bolt with a posi and thoes 3.55's and I run Mickey Thompsons that hook really hard. I am planning on making a run to the 1/4 in about a month or so. We will see what she runs. I think that with a little tinkering the 12's are not that far away. Thanks for all the info your knowlege is very helpfull. If you would like to see pics of the car just e-mail me and i will send em.