Stroker small blocks - what intake?

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M1 single plane, or RPM air gap, depending. I havent run the Victor yet, but I'm sure at point I will.
 
Considering my cars weight (3840 w/me) and 2.94 gears, would a dual plane rpm be a better manifold than my strip dom? The car has a solid roller, 10.8, 255/264 @050. Low first gear 904 and a 10". The car is a cruiser, and runs great, but I just want to make sure I wouldn't lose anything in the 4-6K range with the RPM. I shift at 6200.
 
That's a medium sized cam for a 416. Have you put it on a chassis dyno? The dual plane might be restrictive for the long stroke over 4-5k. The Air gap ones I've built in most cases are mild and smaller cams, and the power is done at 5500, even tho the torque is hueg right off idle. If you have a low gear set, and a slick convertor, you may be better off with the single plane, or a smaller plenum single plane, like a Torker. What do you have now for an intake and convertor?
 
I've had the car on the chassis dyno twice. It made 432 ft lbs tq @ 3500 rpm, and 366 hp @ 6,000. I am running a port matched strip dominator with an HVH spacer. The converter flashes to about 3k.
 
What heads are on it? Those numbers tell me it's got too small a port (my opinion anyway...). The port includes the intake's passages, and the plenum size may also be a little small. That HVH (if it's the 4 holer)the reduces plenum size, usually adding torque and lowering the rpm the peak is at, on an intake that may have a small port, but a larger plenum. (It helps bend the air, and reduces the large single plane plenum.) Does the torque drop off, or stay strong until near the HP peak? What is the cam's lift and rocker ratio?
 
They are ported edelbrock heads. They flow 280/195 at 28 inches. The camshaft is 624/624 @.050. The carb is a 750 dp, an old Barry Grant unit. Do you think I should be using something like a Victor and a larger carb? It does seem to run out of breath upstairs. Exhaust is TTI 2.5 all the way. I am changing it to a 3" headpipe and X, and keeping the 2.5 tails. Thanks for the advice.
 
All those sound fine, except the intake and carb. See if you can borrow a larger carb. Either an 850 DP, or an 870 Vaccum Demon or Avenger..The VS may be easier for your kind of racing...I would also suggest a larger plenum intake, and either an open spacer, or none at all. The Victor might work well on your setup with a vaccum 870. Another choice would be a cleaned up M1 single plane with an open spacer.
 
Thats interesting. I did speak with Ryan J from Shadydell once very briefly. He seemed to lean towards the Victor as well. just too large? They seem The VS idea is something else I may try, but they are hard to find used. The 850 dp is cheap enough to try used.
 
In the range you specified, the victor may make more power. That 4" arm does some cool things, one of which is make the larger port/plenum work like a smaller one would. Same with carbs. The piston speed they generate really moves some air at lower engine speeds, so a large port helps, as opposed to hinders at slower engine speeds. As long as your heads can move the air (and they can), the intake can be a large port, and not lose much on the bottom. I think the carb and intake right now are the choke. The Victor may not clear a hood tho...
 
One thing I did do today is drive with a vacuum gage in the car. I was able to accelerate in second gear to about 5K before running out of road. I noticed the vacuum gage read 2" and climibing when I let off. Is it possible that the larger carb will be the cure without the intake change? To me, the Victor looks very similar to my strip dominator. Am I mistaken?
 
2" of vaccum is a lot. Try the carb first, you may also try the bigger carb with no spacer, then with an open one, if you can get to a track..We're on the 10th or so straight day of rain, they say it should dry out tomorrow, so maybe NE tracks will be open again...lol. The Strip Dominator looks similar, but I'm sure it's got less volume in the plenum and ports. Also, the ports tend to be shorter, which is why the power band is listed as starting at 3500. You may just find the carb is enough to get you a little more power, with no loss in lower end, where the manifold and carb might lose you a little down low, to get more in mid and higher ranges.
 
I agree, and thanks again for the advice. I will be playing around with an 850 and the open spacer. The spacer I have is a 4 holer....
 
I finally got a 4781-5 Carb (850DP), and all i can say is wow. I used my LM-1 to observe the fuel curve and it is much smoother than the old BG 750. The revving capability is tremendous. I used it with an open spacer. I will be at Englishtown on the power tour in a couple weeks and hope to do a back to back if time allows.
 
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