Thread: Possible Group Buy Intake Manis!!! Taking Orders!!!!

well going by their info, the manifold i have should flow really well especially with the plenum size and design and my runner length would come to 150mm.

But they mentioned that having a flat surface on the opposite side can create a turbulance in the airflow as well as having a squared shaped plenum. A tapered plenum where it starts large by the first cylinder which in our case would be #4 and then tapers down to the end and extends past the 1st cylinder a ways. Thats exactly how this one is built.

http://www.amsperformance.com/pdfs/intakemani.pdf
There you go....the link that you posted is the opposite of everything that I was ever taught and have read. I have also seen it first hand in the design's of o.e. manifolds. Look at a B series Honda, the engine's that make power higher in the rev range, ex type-r manifold vs a gsr or regular b16. The skunk 2 copy of the type r for the b series is a short runner design,makes more power only in the higher rpms with the right supporting mods. If you have any other info on this throw it up here. I enjoy discussions and not arguments. Keep up the info please, I like learning new things.
Drew

I'd be nice to have a little more top end power. but all in all I just want it to fit good. If it gets to long won't it come close to the firewall? I mean it looks like your only talking about 50mm difference though.

personally i feel if he is going to make them to spec then he should also make sure fitment is correct. esp if you are needing certain diameter of runner or length all should be made sure by the builder that its going to be right for the customer....but see this all is where you get into r&d and its not a simple cut of the stock manifold then weld on a larger plenum, this is where things take time, and tim is money, so i imagine unless he is a cool dude, the price is going to jump if people are going to need certain soecs out of their manifold that take him a longer ammount of time to get right. could be wrong though

generally the longer the runner the lower the peak power. but this is not all. the taper and diameter also come into play...

yes yea guys are right fitment will be hard with that large of a plenum and longer runners. what you should have him do is keep the plenum the same and for longer runners just have them protrude into the plenum so it does not interfere with the clearance. this will not affect the power or flow of the manifold.

Agreed, I don't think that having the runners protrude into the plenum will harm performance at all. This will be good for the n/a folks who will need slightly longer runners to take advantage of any gains from this type of manifold. This creates less turbulence at the beginning of the runners and if sized and tapered correctly will create a very good intake velocity.

Also agreed. This man has done some personal R&D on a bolt on ve and had very good results with holding power in the higher rpm's. There are many things that come into factor in intake manifold design. As a general rule, shorter runners=higher powerband gains, longer runners, lower powerband gains.

what do you think is a good runner size for turbo and n/a. Like i said these come out to right at 6" from the top of the velocity stack to the head which is 150mm. Should make for a pretty good topend especially with turbo use.

with runners isnt it important to measure them from the valve to the top of the runner? what specs would you use for a N/A ve were you want to improve your peak tq and hp numbers?say your peak tq is around 6-6500 rpms and peak hp is around 75-8000 rpms and you dont plan on reving higher than 8.5k.

I am not sure myself as I have not built a ve of my own yet. I have installed a couple in some customers vehicle's and they were more budget builds than anything which a stock one was used on one and the other used th N1 kit with a slight port job that was just to clean up some of the casting marks. This was way before I knew as much as I do now about the N1 intake design, which since a big ve build is in my near future, I will not be using. I would have to do some testing and measuring of the stock units which I don't at this point. I would start with what is known to work on a mildly worked unit for n/a. I have only seen 1 person that has shown back to back dyno graphs of a decently made custom intake manifold with shorter runners which held very well in the upper rpm's. If you want those specs I believe that cory has a thread about his intake manifold that he either had made or made himself. This would all be theory still as I have not seen or done any dyno's of different runner lengths besides cory's and that has a different plenum so the specs of his would just be a starting point. In all reality, the dyno's should be done in a car with this plenum and changing runner lengths to see how it reacts. Cam choice will be crucial to match the powerband of the intake manifold so I would use the most common set of cams for the testing which would be the N1's at this point. With at least N1 cams or bigger and every engine will react differently but similar enought that a manifold with decent gains, but certainly not optimal for every engine, could be made for N/A that should hold the power higher and make a decent peak gain. I think that it should be designed for peak power around 82-8500 and try to hold the power to above 9k before it starts to fall off fast. This testing should be done on the manifold should be done before any mass production starts. Untill it is actually tested it is just a guess. Most people wouldn't throw up the money like that, even though it is cheap for an intake manifold, based on a guess without dyno proof. Even then if one person seems to not get the gains they were expecting, it will hit the forums and then the sales will slow consideribaly. I hope it all works out but there is a reason that real companies hire engineers and do research and devolopment. It costs money, since there are no manifolds to straight up copy for the VE, real world knowledge is required.