So I'm thouroughly disgusted with my dual quads. If they werent bolted on the car they would be in the woods right now. Looking to run a single 4bbl and going after a high hp number. It made 500 on the dyno with the 2x4 and those carbs are shitty. Here's the specs- -506ci (stroked/bored 429) -large solid lifter cam -3/3500 rpm stall, C6 auto trans -made peak HP around 5700rpm as I recall, dont plan on going over 6K just for long gevity. -will run a standard dual feed carb (not dominator) What would be best? Here's some I found... http://store.summitracing.com/partdetail.asp?part=EDL-2966&autoview=sku http://store.summitracing.com/partdetail.asp?part=TFS-53400111&autoview=sku http://store.summitracing.com/partdetail.asp?part=OFY-6157&autoview=sku Ideas on what size carb to run too would be great, thaks alot guys -Dean
At the time I had my 460 (Some time ago) HRM did a dyno test and decided the Offy Port-O-Sonic made the besr horsepower. It also had the greatest range of egts of any manifolds tested. So it was a lousy manifold that worked well. It was the only manifold I ever had on my 460 and ran good with a 1100 CFM Dominator. Had 13 to 1 pistons a Crower flat tappet race cam and home port job with 429CJ valves
If your not heading to the far side of 6 grand and the motor was out of Wheaties at 5700 then why bother with a single plane intake designed for 8000 RPM? Your giving up a ton of low and mid-range power with a single plane intake with that combo. Tossing parts that "make big power" and have high RPM capability at a motor doesn't usually result in a high HP motor. The combination as to be right. 500hp sounds a little soft for a 500 inch motor with a "large solid lifter cam". Sounds like your head and/or cam restricted if your going to wind it past 6000RPM and still make a 'high HP number'. If you've got to stick with the cam/head combo your using then you may need a dual plane intake for best all around performance under 6500RPM. The one intake many 385 series diehards use is the Weiand Stealth, its available in standard 429-460 intake port and 429 CJ intake port sizes and is under 250 bucks. Use a 1 inch spacer if you've got room under the hood. Its apples to oranges but we just finished a 9.5:1 331 SBF stroker that put out 400hp at 6500 and 370 ftlbs of torque from 3000 all the way to 6500 (yeah....the curve was pretty much flat). The customer was very specific about the motor being pump gas friendly, very driveable and be able to tolerate 100+ degree heat with AC, thus a compromise with a smaller cam and lower compression with the aluminum heads. Anyway....we used a Weiand Stealth on that combination and it worked suprisingly well.....we're RPM Air-Gap fans for all-around street performance but the Weiand really suprised us. I don't think you'll be disappointed if you choose to go that route. There are a couple of 385 series websites/groups out on the net that will have some great information for you to use when sorting out your motor's combination. As for the carb, my first thought would be that the motor may like an 850CFM carb....but I'd still try a 750 first....more common=easier to borrow and try out. Throttle response would be more crisp and the motor may like it better than the 850. Gotta try them both if you can. -Bigchief.
Also I see that Holman and Moody..http://www.holmanmoody.com/memorabilia.html makes a few for the mighty LIMA. We all know those guys could get some balls out of a Ford.
That is the Blue Thunder 4v dp intake...they are a dealer. Not a bad intake, but the Stealth is easier to obtain. I would not expect to see an incredible difference between the Stealth & the dual 4 bbl., unless the carburetors on the 2x4 are not tuned effectively. The 2x4 does have some known distribution issues (as do most intakes of one design or another). My personal choice, given what you've mentioned about the engine, would be the Stealth...it likes bigger CI/more RPM/more camshaft as compared to the Performer RPM or RPM AirGap. Both have their place & the avg. 466 "rebuild with a cam" is better off with the RPM, usually. What distributor are you using?
Dizzy is a MSD ready run unit (no box). I LOVE the look of these dual quads, but they have been nothing but trouble. I just spent $350 on having the carbs rebuilt and went to fire it up and had gas gushing out of every possible place of the front carb. I think the runners are too big too, looks to be CJ size maybe when my heads are Thunderjet heads. Are the big single plane manifolds no good for my rpm range? I'd like to make the highest hp out of this mill I can, I've been hearing good reviews though on that Weiand stealth. btw the cam duration @ .050 is 256 intake, 267 exhaust. Lift .589 intake, .615 exhaust. Thanks guys, -Dean
Sounds like the float level on the front carb need to be adjusted and/or there is dirt in the inlet needle. ....easy fix. The best manifold for max power at your budget level is going to be a dual plane single 4 barrel intake. If your using standard 429/460 heads (your ThunderJet reference suggests that is the case) then your all done dancing at the 5500ish range on a 500inch motor unless the heads have had CJ size valves installed and the required bowl work, port and polish to go with them.....and even that is a compromise compared to the nice heads now available for these motors. The single plane intake and especially the tunnel ram will do nothing to make you good power on this combination. Those manifolds are for 6500-8000+RPM range....something you won't see with this combo. Because the heads to do not have the capability to move the air the 500 inch motor will need your restricted in the amount of power you can make with it. A large single plane intake is not what you want to use on this motor unless you buy good aftermarket heads and build the rest of the motor to run at higher RPM. A good dual plane like the Stealth is probably your best bet. You still may only make 500-550hp but you'll have a mountain of torque and much more driveability. There's plenty of cam in the motor.....but the heads aren't going to support much more power than what your making now. Sell the dual quad stuff and save up for a set of aluminum CobraJet or Blue Thunder heads and go from there. The heads are where the smart money is spent first. -Bigchief.
I built a 506 for my '34 three window, and used a Weiand Stealth intake. Worked out really well on the street...
Of the three single plane intakes you looked at, the Victor is about the best, out of the box. The TFS can be made to work as well, but it is somewhat less effective "as is", according to a number of reliable sources. The Port-O-Sonic had its day, but wouldn't be my choice for single plane intakes. The Torker II can be good as well, if there is not enough hood height for a Victor. However, I'd still prefer the Stealth, which is being used by a number of low 500 CI engines very effectively, for your engine. I would bet pretty good money that you would see little, if any, improvement with a Victor- compared to a Stealth- for the rpm range you are running....but the Stealth will be more tractable on the street. As Big said, look at both 750 & 850 carbs if you can...if in doubt, run the 750 VS 3310 Holley. If you had a larger engine, or some other changes, the Victor might have an edge.... Ditto on adjusting the float levels, before anything else. Get the carbs sorted out a bit more, and then I would look at the advance curve. Do you know what initial timing is in it now, and then how the advance is set up? Also, have you set the lash recently?
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