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Direct connection carb tune up

BadBee

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Hello All,
After reading the thread TUNING a SIX PACK I'm looking for any input on these Mechanical
Carbs these are OOTB new unused on a mid 440/.030 with 906 heads pics are below, I was going to take the current cam out and put in a 509-292/292 in her but I think the springs on these heads are to "WEAK"? All input APPRECIATED!!
Thanks,
Mitch
 
6-Pack: That is a "triple-pumper" setup typically used for race only with HUGE cams/heads/etc. and in my opinion are WAY too much for a 906-head motor with a 292/509 cam.

292/509 Purple Shaft Cam: A good cam in my opinion if you don't have power brakes (very low engine vacuum, so little/no power assist when coming down an off ramp). The old Direct Connection book said the 292/509 cam was "on the borderline" between needing "big"single valve springs & "small" double springs (fyi-doubles require cutting the valve guides & adding Perfect Circle smaller valve guide seals for clearance). If your spring are stock, I would definitely NOT run them with that cam. There's another guy on here that's is trying to do just that & I believe he's getting valve float (motor cuts out at 5000 rpm) and is flirting with disaster of dropping a valve & locking up the motor.
 
Hi Purple,
Back in the DAY I ran these carbs on my '69 Bee 440 with 12 1/2-1.13-1 hi domes, 575 on the Dyno, I ran em with a GENERAL KINETICS cam (AWSOME) cam! 67 915's ported and flowed at AIR FLOW RESEARCH in Ca. These current heads were milled.025 but!! I guess I'm gonna have to check valve clearance so with that said, I'll pull heads and do the springs, or maybe go with TRICK-FLOWS! thanks for the IP!!
Mitch
 
Hi Purple,
Back in the DAY I ran these carbs on my '69 Bee 440 with 12 1/2-1.13-1 hi domes, 575 on the Dyno, I ran em with a GENERAL KINETICS cam (AWSOME) cam! 67 915's ported and flowed at AIR FLOW RESEARCH in Ca. These current heads were milled.025 but!! I guess I'm gonna have to check valve clearance so with that said, I'll pull heads and do the springs, or maybe go with TRICK-FLOWS! thanks for the IP!!
Mitch

Oh yeah... I forgot the 292/509 cam is borderline for piston-to-valve clearance too (good thing YOU remembered). I've always liked those triple-pumper setups, but have never had a hot enough motor to use them effectively.
 
Kicking my *** I sold my BEE way back but ID probably not be writing now, I WAS A NUT!!
That S.O.B did 10.80 in the street, it would PIN YOU TO THE SEAT! I always used a '67 Block and 915 heads + ALL THE EXTRAS I COULD, that Six Pack set up was deadly, but when Sunoco 260 went from 98.5. To 94 octane it sounded like some one was in my motor with a sledge hammer,going to the airport for ave gas and cam 2 was a major PIA!! Moroso fuel additive SUCKED! So I parked her then F-CKED myself and sold her,can't find her either.Now with the Dart this SUCKKA wants to LIFT OFF AND FLY!!! Well I'll keep you informed,Thanks Bro!
 
Those look like the springs I used to have. No good!
I am running a 292/509 hydraulic purple stripe cam with CompCams single spring w/flat spring inside:
https://m.summitracing.com/parts/cc...-_-comp-cams&gclid=COe4v5fp19QCFUWBswod_JUC8w
10° locks and retainers, and CompCams lifters. I don't recall the closed/open spring pressure of the new springs (they work great), but I replaced the stock springs because of the motor floating valves (I could feel it) Had the stock springs tested and they were weak on pressure open and closed. The new springs, lifters, etc work GREAT! Sounds amazing, still plenty of off-idle torque, and with a stock 71 short block spins willingly to 6,200, pulling all the way. I believe that I am probably going past peak HP vs. RPMs, and hope to get on a chassis dyno soon, but it seems to want to spin up there.
I set my rev limiter at 6,200 and shift light at 5,800. Next trip to the track I will force myself to shift out at lower RPMs for a couple of runs and see how that affects my ET and MPH.
Did I mention that cam sounds AWESOME? LOL.
 
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Thanks BIO! What heads did you have, 906's?
Mitch
 
Thanks BIO! What heads did you have, 906's?
Mitch
Nope. Lowly 452s. At least they have hardened valve seats. I have heard that they have plenty of "meat" to port, but I am going aluminum when I get the stroker built. I am going to "fog" my current motor, wrap it in plastic, and manually turn it over every few months, to keep it as a "backup". The exception is the intake and carbs which will go on the stroker.
 
those springs are some kind of aftermarket hipo. count the coils; look like 911's. take one off and test it.
 
Hi LEW AGAIN!!
My other option was by the time I took the heads off and brought em to the shop and went through more $ I was considering 440 Source Stealth heads just for the street, motor only has 5K on it .030 over cam is mild so I figured the 509/292 with 440 Source heads to give it a LITTLE MORE OOOMPPP. What do you think about those heads OOTB? Or as I've read have the shop go through em first? New retainers? Or are they using Comp stuff now?
Thanks,
Mitch
 
440 source heads OOTB don't come close to advertised numbers in the real world, but edelbrocks don't do advertised numbers either. if I did the 440 source I would send them out for a "tune up" before installing.

I don't like big hydraulic cams of any type. they're just power robbing tune-up headaches.
 
FYI, if it wasn't already said, with those aftermarket carbs, nothing Chrysler had for tuning tips would apply. Hell, I'm not convinced they ever did for my stock 6 BBL in the '70's. Those carbs will need plain old tuning, dyno could help.
 
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