First track run - less than exciting....

-
Well - it seems I have the hood clearance to do this.....Just gotta save for the carbs now!

IMG_0313_zps531984ba.jpg



IMG_0315_zps9175e3be.jpg
 
I understood the question as what cfm does a 6.1 intake flow- which can be answered by stating the throttle body is the restriction point, which flows about 800 cfm. If you open up the port, you increase the flow.

Correct me if I'm wrong, rat, but were you not looking for a comparison when sizing your carbs? If you were looking for flow bench numbers of a 6.1 intake on a single port- that I don't readily have available.
 
Uhcoog1 said:
I understood the question as what cfm does a 6.1 intake flow- which can be answered by stating the throttle body is the restriction point, which flows about 800 cfm. If you open up the port, you increase the flow.

Correct me if I'm wrong, rat, but were you not looking for a comparison when sizing your carbs? If you were looking for flow bench numbers of a 6.1 intake on a single port- that I don't readily have available.
Click to expand...

I guess to ask it another way....what is it about the EFI intake that means the lean out issue doesnt happen?

Is it the amount the intake flows per minute, or is it air speed, or a combination of both?
 
Rat Patrol said:
I guess to ask it another way....what is it about the EFI intake that means the lean out issue doesnt happen?

Is it the amount the intake flows per minute, or is it air speed, or a combination of both?
Click to expand...

It's the EFI. The fuel is injected at the port at the right time, amount, and place and the intake has only air to run through it. One of the many advantages of EFI. We have to rely on the design and efficiency of the intake on a carbed engine which in this case sucks so the dual quad top may help the fuel distribution.
 
Well...we trialled an 850 double pumper today and PRESTO.....lean bog completely disappeared!


This was with a down and dirty tune...I'd probably run it leaner if the carb was staying on.


But the guts of it proved that it needed more fuel on a rapid secondary transition.

IMG_0318_zps71bc641d.jpg
 
Great news rat--Keep feeding the monster and forget anything to do with vac. secondary's---Steve
 
Oh and now that i'm home we have 84 squirters in our carb both front and back--Steve
 
As long as people learn form our experience...that's the crucial thing.

I'll use the single 800 AVS - until I can spare the $$ for a set of dual quads...
 
Rat Patrol said:
As long as people learn form our experience...that's the crucial thing.

I'll use the single 800 AVS - until I can spare the $$ for a set of dual quads...
Click to expand...

i dont understand... it ran with the holley... leave it with the holley...
 
Nice to see you post,been watching the thread. Now you know ,what works. A damn good start. Been watching, good luck.
 
Save yourself the aggrivation , go the DP holley , 750 cfm should work well on a stock 6.1.

Go back and re- read Hemijoejr's second post.
 
mo-cars said:
Save yourself the aggrivation , go the DP holley , 750 cfm should work well on a stock 6.1.

Go back and re- read Hemijoejr's second post.
Click to expand...


Mo-Cars - I'm not understanding where you are headed.......I saw where HJJ stated he had no bog but a 60 ft time of 2.0 secs.....but he was running a 2500 converter.

Mine flashes to 3800... So are you saying it'll still be a pig with dual quads?


https://www.coperacingtrans.com/pro...d=246&osCsid=6501bdbb45c8f3bdd026c113833318df
 
hemijoejr said:
Due to the difference in the "K" value I was curious to know what the physical size is. You can have an 11" converter stall at 3800 rpm behind a 640 CID 950hp beast and the same 11" converter will only stall at 1800 behind a stock 273. My six pack was sort of like that. I think youre issue as you know is purely vacuum signal to the carb and a good Holley should be able to be tuned through it. I have had my dealings with Carters and Eddys. There are just some things that can be done with a Holley that can't be done with a Carter/Eddy. We have one of the most modified Carter AVS carbs on my friends F.A.S.T. Dart and it was a total bear!! I mean bored out for bigger throttle plated and completely modified and reworked within class rules.
Click to expand...

Hi Rat I was refering to the part where HJJ said (quote there are some things that can be done with a Holley that can't be done with a Carter .

I'll try to explain . The double pump Holley has two accelorator pumps and four nozzles , 'one for each barrel' , and each is adjustable for duration and volume . So there is a lot that can be done to cover that lean bog when the pedal is smashed to the floor and the slicks bite the track .

The Carter only has an accelerator pump for the primarys , so when the bog occurs you adjust by slowing down the opening rate of the air door , to suit your gearing , convertor , vehicle weight , and engine torque .

You might find the bog free setting but it will likely compromise your 60 ft times .

Hey i'm not an expert here , so maybe start a" Carter vs Holley for drags " tread in the fuel air systems section of the forum .
 
I think what you say makes a lot of sense.

I guess the only thing the jury still doesnt know is if the issue was more about the pump shot...or the vac sec design.....?
 
Squirters to 40?????? I have 73's--65's and if you go that big you have to use the special screw because it's modified for more flow---Steve
 
After I thought about what I had wrote , I thought it sounded like I was implying that a double pump Holley is the answer for all bog related issues , which it is not it's basically a race carb .

In answer to your question [ quote is the issue more about the pump shot or vac sec design .

I think it's the large plenum single plane manifold ( as you have already mentioned ) and the Carters Air valve secondary design not being able to cope .
I can't think of any factory installed carter being used on a single plane manifold , the Hyper Pack is an exeption .

So what I was trying to say was if you intend to stick with that manifold the double pumper sounds like it will work as you have found out , I think it would be a good idea to try it out at the track with maximum traction .

And another thing to consider , I believe Hemijoejr is using a dual plain manifold under his dual Carter/Edelbrocks.
 
You must log in or register to reply here.
-

Back
Top