Baseline carb suggestions for tunnel ram

Posted By: MadMez

Baseline carb suggestions for tunnel ram - 07/08/14 07:56 PM

I finally found a Wieand low deck tunnel ram for my 383. It is built up pretty good in an old school way. 11.5-1 TRWs, .557 lift x 296 duration solid DC cam, ported OS valve 906s. Right now I have a Torker and a single Holley 750DP.

I am going to use two Holley 750 double pumpers. What would you gentlemen suggest for squirters, pump cams, jets, PVs or not, all that stuff.. The usage is street and strip with more street. The car is a 64 Dodge 440 with a 4 speed and 4.56 gears.

Thanks!

Tim

Posted By: Cab_Burge

Re: Baseline carb suggestions for tunnel ram - 07/08/14 09:16 PM

Make sure and get the same, identicle LIST number Holley carbs(IE 4779-1 or 4779 no dash or 4779-4 and so on

), verify all you can verify on both carbs. as far as idle air bleeds, high speed bleeds, start with the stock Holley jetting, power valves and squirters also to start with

Tune from there, do the basic set up as far as the throttle settings on both carbs to match as far as the throttle blades are open and so on

Make sure and check the throttle linkage travel and wide open throttle checks

Posted By: JohnRR

Re: Baseline carb suggestions for tunnel ram - 07/08/14 09:48 PM

A pair of 750's on a tunnel ram is a little overkill on a 383 don't you think? Throttle response would be better I would think with something smaller ?

Posted By: gregsdart

Re: Baseline carb suggestions for tunnel ram - 07/08/14 10:45 PM

At 6800 rpm, a 383 pulls 753 cfm of air at 100 percent efficiency. Running two 750 Dps, they will work well about there, but probably not very good below there. I would call Holley tech and ask what they recommend. There are other options, like vacuum secondary carbs that might be better suited to your deal, especially if you don't have a 5,000 or higher stall converter.

Posted By: ademon

Re: Baseline carb suggestions for tunnel ram - 07/09/14 12:17 AM

I've been on the lookout for the offy 5186 low rise dual quad intake for my mild 383 4 speed RR. From the research I have seen most guys seem happier when they went down to the 500cfm Eddy's or twin 450cfm holleys .

Posted By: Mopar-Al

Re: Baseline carb suggestions for tunnel ram - 07/09/14 02:53 AM

two 660 holleys will work well when matched and tuned. At least it did for me

Posted By: MadMez

Re: Baseline carb suggestions for tunnel ram - 07/09/14 05:08 AM

I have the 750s. Carbs are expensive!

Posted By: MR_P_BODY

Re: Baseline carb suggestions for tunnel ram - 07/09/14 05:35 AM

Quote:

I have the 750s. Carbs are expensive!

Being that you are gonna run the pair of 750s you
can cut down on the squirters and jetting... your
gonna need to test for YOUR driving style.. but I'd
start
at a 28-30 squirters and maybe 70s all around on jets
but once you figure out the jetting then swap in a
pair of PVs on the primary of both... this would be
pretty close to where I would start... remember you
have 2 carbs that basically draw half the air each

Posted By: JohnRR

Re: Baseline carb suggestions for tunnel ram - 07/09/14 03:48 PM

Quote:

I have the 750s. Carbs are expensive!

I assumed that is why you are running the 750's , try trading them for something smaller if they don't work out ?

Posted By: Cab_Burge

Re: Baseline carb suggestions for tunnel ram - 07/09/14 05:02 PM

Quote:

I have the 750s. Carbs are expensive!

The right foot controls how far oepn the throttle is

I like the 660 center squirters and the 750 D.P. for street tunnel rams

1050 Dominators for race motors

Posted By: Thumperdart

Re: Baseline carb suggestions for tunnel ram - 07/09/14 06:47 PM

A common practice on t-rams to controll/maintain leaner idle/cruise afr`s(hope u have a wideband)is to lower the ifr sizes down a bit and as stated less jet and bleed tweeks for wfo............

Posted By: David_in_St_Croi

Re: Baseline carb suggestions for tunnel ram - 07/12/14 03:56 PM

On our low deck based 452 with a Weiand tunnel ram we have 2 Holley Ultra HP 600's. Apparently they were a pain to get dialed in but eventually Dan got there. The carbs were my choice precisely because of all the built in tuning options plus the idle air bypasss. I do not know what jets and air correctors were in the carbs originally so can not compare to what is in it now. It is close to square jetted, 70hf in primaries, 71 in secondaries with power valves in front and rear metering blocks. I think they are 6.5 but they were hard to read. Not sure on the air correctors. Linkage is set up progressive, carbs sideways mounted.

Engine is not in the car yet but hopefully this weekend at least get it set in place so it can move under its own power (hurricane season and all that).

I just recently purchased DAvid Vizard's book "How to supertune and modify holley carburetors" and it is a very informative read. The proofreading and depth is not up to his "Tuning BL's A-series engine" but still worth the read. He does a very good job of explaining how all the circuits work and which direction to go. Might want to consider looking for a copy. I used Amazon as I can guarantee it is not in the one bookstore on island.

Mr. Vizard highly recommends a wideband. Eventually we will get one as we have three cars we could tune with it; the RR, Michelle's 67 Landy, and our 63 MG Midget (assuming we bring the MG Midget down from Bab).