i have this damn tunnel ram on my small block and its driving me nuts i cant tune these carbs anymore i think there shot i want holleys can i please see some tunnel rams with small carbs 500 or 600's on it ..so i can get a idea on what i need to switch out ....so i can drive this thing with no trouble ..thanks edelbrock 650 carbs fellas ...
I tried 2 600's in hot rod and had quite a time tuning. It was a 331, 4 speed, 2300 lb street car with 3.70's. Then I got 2 390's. They required some pump shot and cam tuning but worked out fine, even at idle. I got them to the point where there were perfect at any throttle position.
you didnot mention which carbs so i looked for one of your older threads afb type carbs are the easy ones to tune saw photo with little air cleaners >they are too small >see any real rpms too rich............ are the stacks fake or?
What carbs on now ?? How many cubes? Vac*** at idle? Most (I think all) Holly's have to mount sideways...linkage is EXPENSIVE. I have been running T-rams with AFB's (750's) for years now on my Poncho...very responsive and idle fine... I would not hesitate to run on street. I had to drill out air bleeds as my Idle vac was only 5.5" due to large cam..When you first install carbs make all adjustments the same on both carbs as a "base tune" and keep ALL adjustments the same/equal on both carbs.. JMO..
Twin 600s on a 454 great response all the way through the RPMs,but loads up a bit in traffic but the most driveable tunnel ram I've experienced this is in a 2500 lbs car with a 3500 stall and 3.55 rear gears
650 edelbrocks i thought i mentioned that ... 350 small block dont know the cubic inch sorry pretty stock with headers stacks are on top of the air cleaners non flow threw ... they used to work very well ..i talked to the tech line at edelbrock they told me how to adjust them i did they worked for a while now there giving me **** again ..air fuel is adjusted just like they said to . fuel psi is at 5 psi all around i have 2 fuel pressure regulators so i know where both carbs are at . there not on progressive linkage i made the linkage thats on them both open at the same time . it runs great wide open with a small popping at top im sure the timeing could use adjustment also it also loads up a little bit but at idle i cant get it to saty at a decent rpm without it reving high to low .like a bad tps sensor on a newer car .wierd , i checked for va***e leaks all is good all the gaskets are new ..did the soapy water and carb cleaner tricks no change in idle ..and now the newest thing, after coming off the gas pedal at a light it will either stall out or the rpms will sky rocket ..it makes no sense to me ???
I have had several tunnel rams with 450 holleys.One on 289 ford then on 305 and 350 chevy.Mine either flooded at idle and shut off or when I went to take off normally,not stomping it to floor,it would just pop then shut off.I finally gave up on them.I know nothing about carb tuning.I may try another though,they just look so blooming cool, I would love to run one.I am sure someone here can help.
2 holley 450s - 28 squirters in both carbs - small accell pumps - pink cams w/ linkage adjusted half way or until it quits loading up at low rpm when you go half throttle - main jets according to plugs - small block, you'll probably have to drill out the jet plates on the secondaries - i went to #82 on both plates w/ a cammed sbf - it will pull down to 1800 rpm in high gear & pull up cleanly - idles @ 1300 rpm ---------- if you're not running holleys on a tunnel, you're going to be disappointed
Forgot you asked for pictures too.. Popping on top end could signal it's running lean. I think 5 PSI is too low..I run 6-6.5. When is last time you overhauled carbs? Have you checked the accel. pumps ?? I run my floats at 11/32 and have no issues. these "punny" Comp 750 AFB's are feeding 507 cubic inches and making over 800 HP !!...and I disagree with being disapointed with NOT running Holly's on a T-ram...Holly's are not the only carbs around..not disputing that they are good carbs. Have you checked for other possible non fuel related problems?
from the tank to threw the filter into a holley electric pump,threw 2 holley fuel pressure regulators 5 psi will bump it up ..into 3/8 line into carbs ..all my plugs were goldish brown except number 1 it was white .. wierd ..rebuilt the carbs a couple months ago new gaskets cleaned all the needles streched the springs cleaned floats ,
May I ask why you "stretched" the springs ?? I ***ume you mean the metering rod springs. They are calibrated for specific vac*** values at idle and cruising speeds. On the track they are not all that important but for street use they are very important. Best to take a vac*** reading at idle and match the springs to that figure ...Your stretched springs may be causing you to run RICH..during Idle and cruise mode. You can "crack" the rod covers open some (Tighten screwback down) so you can see metering rod pistons/caps and run car. At idle the metering rod pistons(over the springs) should be down at lowest point and not bouncing..if rods stay up,bounce,get the right springs for starters. Not trying to offened with crude explanation just trying to get info across.. Note: I adjust my carbs with the throttle linkage disconnected betwen the carbs. Then adjust that to fit with out disturbing the throtte shafts location... My set up idles good (@1,200) and response miimicks FI..And my cam is "big"..284/294 @ .050 -113 LSA with .853 lift !!
god damn tunnel ram is no longer ....cant get it to run right the edelbrock tech guys are not for nothing either dumb or just not experianced in the products they sell
get it running rite with stock type intake then install tunnel ram without the tunnel you have no stacks sticking out
i know it ****s ....im trying to find the adapter to put 1 4 barrel on the tunnel ram so i can still use it ..and have at least 1 stack sticking up threw the hood...
I run 2 600 afb Carters on a low profile intake on top of a relative mild sbc with straight linkage. It didn't run right out of the box but with tweaking it runs pretty damn good and idles at 600 in gear. Here's a little video of how it runs with no stumbling or bogging, I do run a rev limiter which is what you hear on the top end. <object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/uaEZL0opm5o?fs=1&hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/uaEZL0opm5o?fs=1&hl=en_US" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>
ive seen the video before straight up reckless i love it..... i think im going to run single 4 barrel till i can afford 2 holley 500 than put it back on unless i can find a single 4 barrel adapter for the top of this edelbrock manifold...
Sounds to me like the secondary stop is letting the back ****erfly wobble. This sometimes lets air in and sometimes don't. This affects idle speed and smoothness. Could be only one of the carbs. On the p***enger side of the carb is a metal cam attached to the secondary throttle shaft. Then there is a finger from the front shaft that has to just touch this cam at an idle. if there is play there it will give an unadjustable idle speed as the secondary ****erfly opens and closes a little. But if you have it too tight the throttle shaft on the front will bind and not close all the way. And keep the idle up way too high. You adjust this by gently bending the metal cam to get the back throttle closed and held there by the finger without flexing the cam or putting pressure on it. All it takes is a good bump on the linkage to screw up this adjustment.
i will try one of them out tomorrow beeing that i pulled the tunnel ram i installed a single plain manifold so im using one of the carbs im shure i will have to adjust it again ..
The Holley 450cfm carbs designed for dual carb setups are not much more money than a single Edelbrock. I paid $498 at Summit for the pair!
i fixed it a while back got a single tunnel ram set up and used a holley 650 street carb worked out great thanks
I have twin 750 Eddies on my 451. It is unreal! Instant response fantastic idle and unbelievable performance. Damon Khun (fugly-racing.com) set them up. He had been doing a series of white papers on this type of stuff for anyone that cared. Mine are perfect. I made a slight adjustment to the AF screws when the weather cooled off. Other than that in about 2k miles I havent had to touch them. He copied over some of his papers to the diamondback engines page. Here is the link to the carbs, but also if you look to the left on the page you will see some of his other papers. Good stuff and nice to read over to pick up tips. http://www.diamondbackengines.com/technical-white-papers/setting-up-dual-quads/ -Dave
The Jalopy Journal
