I wonder if a stoker motor with its deeper breathing and its ability to produce major torque at the lower end would be effected at lower rpm with a single plane intake with its large, straight runners enough to even notice this loss?
I wonder if a stoker motor with its deeper breathing and its ability to produce major torque at the lower end would be effected at lower rpm with a single plane intake with its large, straight runners enough to even notice this loss?
The longer the stroke, and to some degree the more CID, the less adverse affect a single plane has on torque.
Good engine builders rarely recommend dual planes for big block Chevys, for example, especially strokers. They just don't have to try to get torque, it's there no matter what.
It seems to stand to reason that SBFs with their short stroke wouldn't like SP intakes, but they actually love them because the short stroke won't make power until higher rpms. The SBF loves to rev, and other than the rod bolts, it is very sturdy at moderately high rpms in stock form. I look at it as reverse of the big block idea... The stroke is so short on the SBF that the torque will not be there no matter what, so you might as well be able to rev it to 7k and use an intake that will breathe that high.
That is my personal theory anyway and has served me well.
I think it is important though to use a single plane that has narrower ports and a smallish plenum so the bottom end is not soggy. Victor Jr need not apply unless you have low gears.
As for a 347 stroker, I think that it still needs to rev to 6k anyway, and I think that for street use, a well chosen single plane is perfect.
Dave
For a Stroker on the street, mine at least, the minimal loss of low end torque does not make a bit of difference. With 245/50/16's, 3:70 gears in a nine inch and a 2500 stall the car shreds the tires through first and second no matter what.
But like I said I have not been back to the track on my slicks so I do not know how my 60' times will be affected. Even with the weight I am adding with the roll cage I really believe my 60' time will not suffer and most likely will improve.
I put the my slicks on once this year (Hoosier 26X9.0X15's drags) on the street after the single plane upgrade and ran 18lbs in them, heated them up good on some good concrete and tried to launch to see how it felt. It would not hook which is not unusual as I have never been able to hook anywhere except at the track with 12lbs in the tires. So I really believe that with a stroker and a light car you already have an abundance or torque (if it's built right) and the gain from the high end is well worth it. Just the seat of the pants feel with a SP is tens times better than a DP and I am shifting at only 6200RPM with my XE roller cam.
I have ordered a victor jr so I will let you know the results. The drag strip dyno says its worth 11.2 ET at 122.4 mph in 1/4 mi or 7.2 ET at 99 mph in 1/8 mi. If this is close; which it is usually within +/- .2 tenths; that would mean I would break into the 7.49 mandatory roll bar rule. Even though I have the "need for speed" I don't really want to put a roll bar into my classic stang. Thanks for all the input!