This voice in the back of my head keeps asking me "Could I
sweak out a little more HP if I change to a Victor jr or a Team G
intake."

So I pose this to the Forum. Would I?

My combination is in my sig. It runs great now
But is there more? :rolleyes:

Oh the RPM Airgap does have 1" open spacer
cam specs 242I 248E @.50
294I 301E duration
570I 599E lift with 1.6 RR
I think thats right I'm trying to pull it from memory
Thanks for the help
Mike



[Modified by MCAF84, 5:27 AM 12/18/2002]

 

I am running a single plane in my stroker. The power comes on at a higher rpm than the dual plane but the vette just flies from 50 mph to well over 135 with no let up. I was told that this would happen by a drag racer who needs to run at the high rpms. I set my MSD at 6500 rpm though I know the engine is good for over 7000 .

 

Your motor is probably right on the edge. The limiting factor I see is your hydraulic cam. If it were a solid roller I would say yes try to single plane. You will make more power with the single plane, but how much torque will you give up. With your cam not being able to rev high it might not be a good switch.

If you dont mind the work in swapping it over, give it a try and post your results. :chevy


[Modified by 69 N.O.X. RATT, 3:39 PM 12/18/2002]

 

I still have plenty of low end torque. I can run thru town in D
@ 1500 RPM and not buck or have drivability problems
I usually shift at 6500
The bug in my ear tells me to try it ....
but I want to run the car on the dyno first to get a baseline
I'm also trying to get a feeling of how much torque I will give up
from you fellow forum members
Thanks Mike

 

http://www.weiand.com/HiOctn/ProdLin...AMSM/7530.html

I actually use the 7532 with a 1/2 inch wood spacer.


Our motor build ups have much in common. I just got done digging through the web sites to check gasket sizes. My question to you is: Why are you using an intake with smaller runners than your Dart Pro 1's? There is no way to make that combo run at 100% with intake ports 1.28 X 2.09 inches and head ports slightly bigger than 1.34 X 2.21.

So yes it would run better with the correct port matched single plane. The idea behind tuned port intakes is the added power of the ram effect. Your setup doesn't do that. The reason I know it doesn't work right is becaused I tried it and I finally talked to a knowledgable dyno person at Edelbrock.

As air moves to the intake valve you want the port continueing to get smaller as the air speeds up (LIKE A FUNNEL) Going from small internal manifold passageways to big head ports causes fuel separation and turbulance

If some race shop set you up like that I'd go kick their butt :smash:

 

gkull, that is not always true. I have many times put a smaller intake runner on bigger heads and gained in "useable rpm range" performance. The best example I can give is of a 496 BBC that was origionally running a set of cast iron gm rect. port cyl. heads and a vic. Jr with a 850dp holley. It was in a 67 camaro conv. running a best of 9.60 in the 1/4. I did all the carb/intake work on this guys engines, and at the end of the racing season he asked me to do a dominator for him. I asked him why?, I didn't think he needed one. He replied that he had talked to an engine builder and was going to have the 496 gone over. The engine builder he was going to is the kind of guy that always thinks bigger is better. He ended up with pontiac big chief cylinder heads, a dart/wilson dominator intake and a 1250 dominator! Well after his "dyno tune" and some runs at the strip he was amased that for the $7000+ he spent, he now was able to run a best of 9.58 and gained a whopping 3mph!! He lost .02-.04 in his 60' times! I had told him that it was going to be WAY TOO MUCH for his 496 but the engine builder "builds racing engines for a living, he's not some guy fooling around in his garage out back"!(that would be me). After they spent close to 8 weeks trying to get this package to run, the owner and I got together and this is what we did. I did some minor work on a holley strip dominator OVAL port intake and built a 1050cfm 4150series double pumper. Upon startup you could hear a definate change in this 496. It had a tun more throttle response and idled alot better. The first pass off the trailer went 9.14! He also had a best ever 1.30 60'! By the end of the night he was told to update the car or slow down running a best et of 8.98. Not all of the results are this good, but generally you can make up for too much cylinder head with too little cam by using a smaller intake manifold runner. As for the port being smaller as it gets closer to the valve, Ive always had the best results with both flow #'s and actual hp output when the "choke" of the port was equal to the distance of the stroke of the engine that the cyliner heads were going on. What I mean by this is, if the engine has a 3" stroke, then the tightest area of the intake runner is 3" up from yhe valve seat. I've talked with many head porters/builders, and they also use this as a guide when porting/seting up a set of heads for a particular engine.

MCAF84, if you noticed a gain with the addition of the 1" open spacer, then you will more than likely benefit from a single plane intake. With your set up I'd lean towards the weiand manifold. Depending on your carb, you might not loose any torque, just move it up in the rpm range. Do your baseline tests, and then switch to a single palne, it would be :cool: to see your results! :cheers:

 

gkull It's my butt thats to be kicked :eek: I didn't know how much torque I was going to give up on the bottom end with the big cam and heads now I know that it wasn't much if any :D I went with the rpm airgap and 1" wood spacer because my research showed that it could work to help maintain low end torque and higher end hp. I did gasket match the intake to help smooth out the transition.

It will be after the holidays before I can run a baseline on a dyno I will post the numbers when I get them

Thanks Mike

 

(sinistervette)

I'm going to find some research material. But the choke spot from what I’ve heard is the area just before the seat. It is supposed to be 85-90% of the valve seat area. I'm not sure how or why you would place a choke area 4.25 or 4.5 inches away from the valve seat on a big cubic inch motor.

Your friends Camero problems were probably the result of too big a carb and plenum volume and it caused fuel separation problems. I would have tried the big manifold and the 1050 carb with maybe even a 4-hole spacer. Most big intakes aren't a slap on deal. You often have to epoxy in turtles to correct distribution problems.

 

The correct answer is you probably will get more HP if the engine is set up for that style of manifold. Very high RPM`s. But notice, L88`s used a dual plane style and produced tons of HP with a solid lifter cam. A hydraulic camed engine will not be able to handle the single plane manifold effectively. Solids would be required. Cooler fuel would be obtained but tons of RPM is necessary. A driver even with a solid cam would be better off with the dual plane for everyday use. Good luck, :thumbs: :cheers:

 

When I was running bracket and Super Comp cars we always played with intakes and carbs to try to get the most consistant combo we could. In all instances the cars ended up with some sort of dual plane. The last Super Comp car had a long rod 461 with ported 077 heads and a ton of cam with a 6000 convertor. We put it together with an 8896 modified with annular boosters and a Team G single plane. I had an old C454 (dual plane Dominator manifold) that I tried. All of the tuning problems disappeared and I was able to go from 4.56 gears to 4.11s with no loss in performance.

 

Same voice in my head,but all dyno's seem to indicate the dual plane has the edge on the street. The engine buildup I modeled mine after lost 30+ lbs of torque and only gained 5 hp on top when they switched from the RPM to the Vic Jr. intake. I'm still playing with timing and rocker ratio and find there's a huge difference when tweaking in this area. I'm keeping my port matched RPM intake,but I drive my car 400 miles a week. It's no trailer queen!

 

LMAO....when I went to your website and the A990 70 Cuda Page I had to laugh with a smile on my face....Your Car Sounds just like my LS6 Vette!!!!!!!!! Did you manage to sneak in here and start it up? I just love the sound.... :cheers: Truely they do both sound the same.... :smash:

 

Same here I have always wanted to try the Victor Jr. but I have seen dyno results on a 500HP small block that gained less than 10HP ( at 6500 RPM anything below it was less ) with a Victor Jr. over and RPM Air Gap and lost a ton of torque. 5 HP on the top end might be the difference in a close drag race but for the street it looks like the RPM Air Gap dual plane is a good choice.