SB Tunnel Ram tunning

Hi,

I dicided move forward from Super Victor Intake to Tunnel Ram. My engine is a 360" with 12.0:1 CR, Voodoo Flat Tapped cam, Eddy Ported Heads flowed 301cfm@.600". I was running with a Super Victor Intake + Mighty Demon 750 Carb. Now I'm planning use two Mighty Demons 750 on Tunnel Ram.

I never had tunning a tunnel ram so far and I would like some advices like jets to start and use or do not use power valve on the carb?

Thanks

Tune the idle circuits first, all eight of them
I would use the power valves for part throttle cruising
Make sure your fuel system will keep the carbs. full of fuel at WOT
If you can't jet the carbs up enough(richer) to slow the car down in the 1/4 mile you don't have enough fuel volume
As far as adjusting the idle circuits on multiple carbs. I have had to screw them in from 1/4 to 1/2 turn out from bottomed to get the idle circuits lean enough to not foul the plugs
All the rest is basic carb tuning, squirters, primary and secondary jetting, needle and seat size needed and all the rest
Have fun, let us know how it goes

Post all of the specs as in jets, ifr's, idle bleeds, high bleeds,amount of emulsion holes and the sizes timing etc. then we can help ya out...............

Thanks Dom,

Carb is a Mighty Demon 750 with annular boosters. About the Jets, I'm planning start with 72 in primary and 84 in secundary.

SQUIRTER: 0.031
IFR: 0.038
IDLE AIR BLEEDS: 0.070
HIGH BLEDS: 0.033
EMULSION HOLES: 3
EMULSION HOLE DIAM: 0.031

Thank you Mr. Carb! I think that will have a lot of work to tunning correctly multiple carbs but will be very fun.

My fuel pump is Holley Blue and I tested this pump some weeks ago and they flowed 124 GPH of free flow... With single carb, I had no issues so far. Do you think that I could have any issues running with multiple carbs?

For sure. I will keep everyone knows about improvements.

The last 750 t-rams I did ended up as follows but your tune may vary;

jets 72-83
idle bleeds .068
high bleeds .029
kills .027
pvcr's .061
ifr's .031 lowered
t-slots .085
squirters .028-.031 pink cams
angle channels .140
needle n seats.120 6 psi max
emulsion .026 in #1 and #3 middle plugged

very little t-slot exposed on primary and secondary otherwise wouldn't idle but less is sometimes better........

Hope this helps you out.......... I'd get a better fuel pump if it was me............

Mind you these were down leg boosters and you MAY need less jet.........Get a wide band if you don't have one already and tuning will come way faster.........

Start out by driving it on the street, if it is street and strip car, at light part throttle for your normal street driving distance and type (except WOT )
Pull all 8 plugs out and look at each one real hard with a good magnafeir Go from there on the primary jetting
Don't be surprised if you end up with 3 or 4 different jet sizes in the primary Tunnel ram intakes are very tunable One barrel per cylinder at WOT

If your car leaves well and your carbs are mounted sideways, you may require j tubes and wedged floats. HTH's

Dom, I really appreciate all your knowledge that you shared with me. Thank you!

I still need buy some parts to fine tune on carbs like bleeds, squirters and needles... But I will do..

About wide band , yes I've one with datalogger, amazing resource!

One barrel per cylinder at WOT looks great..

As you can see at pictures below, I'm having some work at Intake...

Anytime and v floats will help a lot........

I forgot to tell you one important thing about fuel. Here in Brazil we've around 30% of ethanol in gasoline. This percentage of ethanol could change some configurations that you sent me ok?

Not totally sure on that but the WB will help in directional tuning and I know my Dart runs richer on 91 pump than the VP-100 Unleaded I tune and race with...........

Hi Folks...

I'm almost there adjusting my Tunnel Ram setup...

So Far...

Squirter: 31 Pri and Sec
Jets: 74 pri, 80 sec
Cam Pink
IFR: 0.038
Air Bleeds: 0.070
High Bleeds: 0.033

Still little poor when I get WOT, maybe small squirter?

when do you expect to take it to the track again.. what would be atypical air density for you guys corrected of course..

This weekend! I made some changes in my suspension setup to try eliminate bouncing on the start and also I moved from Super Victor to Tunnel Ram. Last night I tested the car on the street and looks great. Looking for something under 6.98 in 1/8.

About the air density. last time that I ran was 1.1467 kg/m3

First Start with Tunnel Ram:

https://youtu.be/ap8u2OfaBCw

She has amazing throttle response great job.. very clean installation

Looking at the graph this looks like a 3rd gear cruise and then a w/o throttle mash since there are no rpm dips to indicate a shift. (This is assuming we are seeing rpm and a single AFR trace). It looks like you go rich and then lean till you recover onto the jets, this indicates to me that you may pick something up playing with the accelerator pump cams to give a longer squirter duration. I see you use lambda rather than ratio figures too which I'm not used to either.

As a side note, I have my tunnel ram carbs set up with one to one linkages and all square jets with the power valves blanked, this seemed a more logical way of setting them up up but I'm no expert and have only just figured out how to get cleanly off the line.