old school tunnel ram and carbs question

musclcar · #1 03-11-2005, 01:43 AM

i'm about ready to put my edelbrock TR1-X tunnel ram on my sbc and need a few questions answered.was there or is there a spacer or adapter to mount the carbs sideways instead of inline.the carbs i'm going to run are 1850 holley's now i'm trying to get a period correct look is this the correct carb used back in the 70's.on these 1850's i was told i need to run a balance tube for the secondary diaphram so to open correctly.was this how they were set-up back then or did they just run independent of each other. now the fuel line routing i'm currently running the stock 69-70 Z28 metal fuel line for holley carbs.this had a 1/2 line from pump to a brass fuel block then (2) 5/16th lines one to each bowl.i was thinking of running rubber hose from that fuel block to each carb does that sound period correct or is there another way.

whitetop · #2 03-11-2005, 02:36 AM

I have set up 2 TR systems for myself and one for a friend who has a street rod. Take this info or leave it but it works. I got this info by trial and error and talking with guys who actually run these cominations on the street and who actually don't LIE to you telling how good their combination runs on the street. I think only 2 out of 10 TR systems I see on street cars actually work decent. Here is the engine out of my mustang-see attachment.

1. Get rid of the 1850 4160 carbs and the sideways linkage. They were hardly ever run on the street in the day and were mostly race car only. Those 4160 double pumpers are way too much for any small block on the street even if they are vac. sec. You will end up with gas washing down your cylinder walls and will be rebuilding the engine by the end of the summer. Run two Holley 4150 carbs with 450 cfm inline. (600x2 =1200 cfm is way too much). I had two of the 600cfm 4150 carbs on my car when I got it. It ran o.k. but the 450's were way better and the 390's I finally ended up were the best. I think the very best carb is Holley 4150 390 cfm #6299 (with no choke) and vacuum secondary. That is what is in my pics. 6299 are discont. by Holley but you can find them on ebay just about every day of the week. Do not run the 390 carb Holley still on the books. It is an emision carb. I used the balance tube kit for the v secondaries and it made the carbs run incredible-great as a matter of fact. The balance tubes were not availble in early '70's but came out in '74 ish period. I'm very picky about being period correct but would run the tubes anyway.

The trick to getting a tr to run good on the street is lots of torque. Get this by running the heaviest flywheel you can find, smallest tube headers, and highest number rear end gears like 4:11 etc. Anything less than 4:11 forget it.

I'm running an early 6530 Moroso y-block with 3/8 mainline and two 5/16 rubber lines to each carb. I've never seen guys back then run any type of OEM fuel blocks etc. Not to say that someone did. Just from looking at 5000 old magazines amd seeing original cars. Also a red Holley street electric fuel pump that puts out around 5 psi. Don't go much over that or you will be washing down your cylinder walls. The blue pump is overkill for the street. I've seen some guys just run a mchanical pump. The only problem is you will be cranking the engine alot each time to get it started. With my electric pump I turn it on for 5-6 seconds and it fills up the fuel bowels and then turn the keys and the engine kicks right off. I had the mechanical fuel pump only at one time on my car and I was always cranking the starter.

Best compression ratio for the street with a tr is 9 1/2 to 10:1. You also need to run a very mild cam that produces lots of vacuum. RV style cams work great. You need lots of vaccuum to pull that air/fuel down that long intake at low rpms. If you are running a rumpity rump cam it's probably wrong.

Also offenhauser made the best tr for the street amd most street freaks of the day (who new better) ran offie. That is what is on my mustang-which was built in '72-'74. Offenhauser Tr's for sbc and sbf came out in 1970 anyway and you can still buy them from offie through summit. I know 3 guys that run offie tr on their sb chev's and swear by them. Also a magazine did a tr comparison backin the late '70's and the offies came out on top for the street. Had to do with top plenum size and tube length and diamater.
I have to go back and see my notes etc. There is alot more info.
Dave

budnate · #3 03-11-2005, 03:42 AM

WOW..great stuff Dave..I snagged a set-up this last fall and have been wanting to read up on proper tuning...please keep sharing your "tune tips"...I really need them as I have never set one up before..

**Salvatore** · #4 03-11-2005, 03:50 AM

Dave, You sound right on. Small Carbs that run 85-90% efficient is much better than big carbs running 60% efficient. Need steep gears and heavy flywheel. My friend Pete used to run a 50lb. wheel with a 6.17 ring and pinnion and a 3.00 first gear in a Nash 5 speed. Car was 280 cubes in a 57 2 door wagon that weighed about 3400lbs. 10.82 @ about 130mph back in 1979. Carbs were inline (660) center squirters with an Engle roller cam. (G/MP)

JoeG · #5 03-11-2005, 04:05 AM

engine whitetop--Are you running a straight linkage ie.-1 to 1 ratio or progressive setting on your linkage

**Mr70** · #6 03-11-2005, 04:53 AM

I'm not really up on street engines,but that looks like one hell of an engine whitetop.

**Salvatore** · #7 03-11-2005, 05:11 AM

I here Marlin is trying to sneak a tunnel ram on his car to run Frankie.

budnate · #8 03-11-2005, 05:58 AM

[ QUOTE ]
I here Marlin is trying to sneak a tunnel ram on his car to run Frankie.

[/ QUOTE ]

Really...well I will ship mine back to Frankie...

**Salvatore** · #9 03-11-2005, 06:12 AM

We got something going here!

**hvychev** · #10 03-11-2005, 07:22 AM

LOL!

Don't tempt me! It has taken me everything that I got to not day 2 my car!

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