DeTomaso Mailing List: November 97, Message #43
     



From: 	"Curt T." <curt@digitalthunder.com>

Subject: RE: To pump or not to pump, is size really important??????

Date: 	Sun, 2 Nov 1997 20:25:41 +0000



Bryan wrote:

Your opinions please,



I was wondering what you guys thought is the better choice

for high-performance street use, a Holley with vacuum secondaries,

or a Holley double-pumper with mechanical secondaries?

What are the pros and cons of each?

Which gives better throttle response?

What's the best size for a mostly-stock 351c?

I know I could call Holley, but I'd rather hear some personal

experience.  Input would be appreciated.



Thanks,

Bryan

Carburetors SUCK!!!!:-)



------------------------------------

I have the 750 Holley double pumper.  It's been on the car about 1 1/2 

years so far and I have no major complaints.  Compared to the old 650 

carb that was on there, it has made a very big difference!  It's as strong 

as the old carb wide open without out opening its secondaries.   Now a 

mechanical secondary since it uses no vacuum should have more power. 

But you do have to push harder on the gas to get them open, I like this, 

there is a definite stop in the pedal at that point.



Problems, I need to change the jets by all indications it is running a 

little lean.  Has had some fuel leaks, very small but you the other day I 

did see fuel drip after I stopped.  It did tighten back up and seems to have 

stopped the leak.  The other problem was has been getting the float level 

low enough to keep it from stalling during a hard stop.  



I would say that the ideal size would depend on a few other factors.  Size and 

type of intake, cam and exhaust.  I have a slightly over stock cam, a Edelbrock 

Performer intake and GTS exhaust all which could help use the extra flow of 

the 750. 



Curt T.

1TO9 MPG, Yes, this carb sucks, and my exhaust blows!