Re: Heads up runs in Stock & Super Stock
 

Nope, doesn't seem like a problem to me. If the carb cars were better, we would be back to racing carb combos. If they combined stick with autos, we would put five speeds in our cars.

Re: Heads up runs in Stock & Super Stock
 

Tom, I didn't think I was jumping on you, I simply pointed out that you decided the car and combo you run. I didn't think it was being personal. If youre going to build a combination for your car, shouldn't you build the most favorable?? Or should you build the combination that's been hammered and beat on?? There are still carb combos out there that are still favorable.

Re: Heads up runs in Stock & Super Stock
 

I'm not offended, I built what I like. Yes there are other combos. I was not trying to make it about me at all just some of the real situations out there. By the way Sean what size throttle body is on your combo? I don't know anything about injected cars. Or any lt1 l98 deal

Re: Heads up runs in Stock & Super Stock
 

Its a 48mm throttle body, smaller than your average carb.

Re: Heads up runs in Stock & Super Stock
 

Thanks, 48mm flows 650-700 cfm. That answers all my questions.

Re: Heads up runs in Stock & Super Stock
 

What questions would that be??

Re: Heads up runs in Stock & Super Stock
 

Fuel injected has nothing to do with it. Those cars have better cylinder heads and more compression than most carb engines. Ask Bobby or Jeff Warren what they saw on their dyno when Bobby put a Quadrajet on his LT1.

Re: Heads up runs in Stock & Super Stock
 

Alex Kadar and I came within one more round win of having a heads-up DF/S race in Rnd.4 (of the Carquest Nationals), but our Rnd 3 redlights through a couple of flies in the ointment of that happening...I know I'd have probably lost the race (given Alex had a .9 sec advantage on me in that race), but I would've earned an extra $100 bucks, and Alex would've earned (at least) an extra $150 for making it to the semi's....that would've been "Way Cool"!!!! :)

Re: Heads up runs in Stock & Super Stock
 

Crickets.......

Re: Heads up runs in Stock & Super Stock
 

Or Jr.

Re: Heads up runs in Stock & Super Stock
 

48 mm flows 600cfm.

Re: Heads up runs in Stock & Super Stock
 

Mine shows manifold vacuum above 6000 RPM.
A Quadrajet would be a good bit faster.

Re: Heads up runs in Stock & Super Stock
 

We dyno'ed with both ... Right at 20 hp difference... But the FI is such a flat powerband it makes up for it ...

Re: Heads up runs in Stock & Super Stock
 

Same numbers Bobby Warren told me.

Ever try it at the track? Hard to think the flatter torque curve would make up for 20. Bobby didn't seem to think it would.

Re: Heads up runs in Stock & Super Stock
 

If a stock 48mm flows 453 from Gm.... How are they flowing 600 and above? Thanks.

Re: Heads up runs in Stock & Super Stock
 

Sorry..... I recheck my notes. 435 from Gm.

Re: Heads up runs in Stock & Super Stock
 

I never flowed one. Where did you get 435?

Re: Heads up runs in Stock & Super Stock
 

We have more heads up races at our local
combo's and association races than most
nationals and divisionals. Just sayin!!

Re: Heads up runs in Stock & Super Stock
 

Ed.... Just Google it.

Re: Heads up runs in Stock & Super Stock
 

OK, thanks.

Re: Heads up runs in Stock & Super Stock
 

These are what I found TPI Intakes and runners

The following airflow tests were performed on the University of Northwestern Ohio's SuperFlow SF600 Flow Bench.
All CFM values are corrected for airflow at 28 inches of water.
Injector flow rates are flowed at 43.5 PSI on an injector flow bench using test fluid with same density as gasoline.

AirFlow

Stock TPI/LT1 48mm Throttle Body w/o airfoil -- 783.0 cfm

Stock TPI/LT1 48mm Throttle Body w/ airfoil -- 821.9 cfm

TPI/LT1 52mm Throttle Body w/o airfoil -- 848.9 cfm

TPI/LT1 52mm Throttle Body w/ airfoil -- 898.8 cfm

Stock 98 Camaro 3800 II Throttle Body -- 554.3 cfm

Stock TPI Bosch MAF sensor w/ screens -- 517.8 cfm

Stock TPI Bosch MAF sensor w/o screens -- 658.4 cfm

Stock 87 GN 3.8L Turbo AC MAF sensor w/ screen -- 584.2 cfm

Stock 86 2.8L AC 5-wire MAF sensor w/ screen -- 576.2 cfm

Stock 96-up AC 3100 V6 MAF sensor w/ screen -- 616.4 cfm

Stock 96-up AC 3100 V6 MAF sensor w/o screen -- 670.7 cfm

Stock 94-up LT1 MAF Sensor w/o screen -- 719.0 cfm

Stock 85-87 Firebird TPI airbox mid piece -- 499.3 cfm

Stock 4.3/5.0/5.7 2bbl TBI complete -- 574.1 cfm (dry)

Stock 4.3/5.0/5.7 2bbl TBI w/o injectors -- 584.7 cfm

Stock 3800 vin L throttle body w/ screen -- 419.1 cfm

Stock 3800 vin L throttle body w/o screen -- 444.8 cfm

4bbl MPFI Holley Throttle Body -- 1287.6 cfm

Re: Heads up runs in Stock & Super Stock
 

From same web page

Flow (cfm) Max. NA HP
Stock 668 300
Stock w/airfoil 710 350
52MM w/airfoil 835 400
54MM (AS&M) 900 450
58MM 1050 500

Re: Heads up runs in Stock & Super Stock
 

Great info. Any track confirmation A.B.A?

Re: Heads up runs in Stock & Super Stock
 

Here is a similar website..

http://gmtuners.com/flow/

Re: Heads up runs in Stock & Super Stock
 

Carburetors are not rated at that high of a test pressure. Raise that, cfm goes up.
Flow a 750 cfm Holley or Quadrajet carb ar 28", it will show MUCH more than 750 cfm.
28" is for cylinder heads.

Re: Heads up runs in Stock & Super Stock
 

28" vacuum is standard = 1.01 lbf/ inch squared

Re: Heads up runs in Stock & Super Stock
 

It is the standard for CYLINDER HEADS! And, not all shops even use that.

When did you get your first flow bench? Over 30 years ago here.

2 & 4 barrels carbs are not even rated at the same depression.

To compare them to carburetors, they would have to be flowed at the same depression.

Re: Heads up runs in Stock & Super Stock
 

My cfm measurement is the timeslip! :-)

Re: Heads up runs in Stock & Super Stock
 

But, we don't know as much as the office guy above. He has Google.

Re: Heads up runs in Stock & Super Stock
 

Sean,

This sounds like a lot of fun, do you think we can make this happen? I'll reinstall my rear view mirrors and get some new brake pads...

Jim Caughlin
SS 6019

Re: Heads up runs in Stock & Super Stock
 

I'm sure if you messaged Matt, he could let you know if it's a possibility. It would be fun, for sure!