[Murf]

I just put a 950 H.P. on my car and I have a couple questions. I would like input on a good tuning book or video. I haven't messed with any Holleys before so I need some guidance. The carb seems very responsive and works almost perfectly right out of the box. The one problem I have is, when I run it up against the converter and then floor it, it kinda stutters for awhile before accelerating cleanly. If I step into it more slowly, like when your trying to leave without spining it performs very well with excellent response and power. I went to Holleys website and , if I got this right, think I may need to play with the squirter size. Is this correct? Would it be the primary or secondary squirter that needs attention? Any input would be helpful.

Thanks in advance
Murf

[Murf]

I just put a 950 H.P. on my car and I have a couple questions. I would like input on a good tuning book or video. I haven't messed with any Holleys before so I need some guidance. The carb seems very responsive and works almost perfectly right out of the box. The one problem I have is, when I run it up against the converter and then floor it, it kinda stutters for awhile before accelerating cleanly. If I step into it more slowly, like when your trying to leave without spining it performs very well with excellent response and power. I went to Holleys website and , if I got this right, think I may need to play with the squirter size. Is this correct? Would it be the primary or secondary squirter that needs attention? Any input would be helpful.

Thanks in advance
Murf

[Gooatee]

I think they reccomend you step up to a 50cc accelerator pump above 35 also if you don't have it already! I had the same problem on my car and between the sqirters and pump change it cleared the problem! I am not in the HP range you are but the priciple applies! I was albe to achieve success by just adjusting parts to the primary! I went from 31 to 37 on the squirter and added the 50cc pump! Summit sells a tuning kit for this problem as well as the pump and several books on tuning Holleys! There's a plug for ya Scott(lol), by the way (hint) give Scott a call and he can set you up!

[Roger C]

Murf go up 2 numbers on the squirters until the stumble is gone,then back it down one side at a time until it does it again,or you can just leave it alone..
Later,
Roger

[Taff]

Check that you do indeed have a lean stumble not an over rich condition. Have a friend watch your headers/tailpipes when you floor it,if you have black smoke you'll need to downsize your squirters,if there's no black smoke go ahead and increase your primary squirters by a couple of numbers until the stumble goes away. You may also need to increase your secondary squirters and/or fit the 50cc pumps if you have a lot of manifold and port volume.

[SCOTT ESTERLE]

Go to a bigger squirter on the primary & secondary side. You are going lean off the line.

[KS circutguy]

I swapped out the stock 31s for 37s and it helped a bunch. No hesitation at all!

<font size="2" face="Verdana, Helvetica, sans-serif">One holley beginner mistake is to over richen the accell pump squirters and cover up another problem..

It's probably rich now,I'd start with changing the pump cam arm.Or go to a different color cam.
They come in a pack fairly cheap at any speed shop.

Then see how it leaves and make sure she ain't smokin on leaving the line..

Also make sure you aren't covering up a fuel volume problem (aka;fuel pump, fuel system not up to par..)

barry grant fuel system test

[ September 10, 2002, 09:37 PM: Message edited by: KS circutguy ]

[Murf]

Thanks Guys! Are the squirters sold seperatly or does Holley have a variety pack of them I could get? Scott, you think I should play with one side at a time or change both at once? Do you want to keep both the same size or do you mix and match?
Rodger, Do you agree that I will need to work on both squirters? Thanks alot for the help guys!

Later, Murf

[Scott65]

Start with the primary side. If you think about it, that's where you've taken away pump shot already by being partway into the throttle. Also, you can move the cam for the primary pump arm to the #3 position. This brings the shot in later in the throttle opening cycle. If you move the cam, re-adjust the arm to take out any slack. Some people will say playing with the cams is a waste of time. For a race car that's true, but for a street driven car, it might just allow you to stay with a smaller squirter, having good response in all situations. Roger and Scott are right, you need more shot, but there are several ways to achieve that. Good luck whichever route you take.

[Scott65]

I forgot, you asked about a book. I've had a book written by Dave Emanuel for years. I don't know it to be the best, as it was written before the HP series of carbs came out. It is very complete in its coverage of all the functions. It also goes into details of modifications for race, street-strip, and turbo applications. Hopefully someone else will know if there are books for the HP's. I've used one of those same carbs and liked it. I just didn't need a book by the time I got it.

[SCOTT ESTERLE]

I was having the same problem with a demon carb & they said to change both of them to the same size. My Barry Grant carb i run currently i was using a 31 primary & a 35 secondary. You can play around with them & see what works best for you.

[Scott65]

I don't think it's mandatory that they be the same. Some Holleys come staggered. Mine worked best with 35f-40r. My car's heavy with not enough converter...

[RPM]

I swapped out the stock 31s for 37s and it helped a bunch. No hesitation at all!