Power loss

[curtis73]

I agree 100% with zagrot, but I wish to add something. The construction of the intake is less critical with forced induction, but only under boost.

For instance, if you construct an engine designed for low-rpm power but use a large, short-runner intake, you'll have sluggish performance. If you add a turbo tuned for high rpm boost, you'll have an engine that is frustratingly sluggish until boost comes in.

Although the intake design has less importance under boost, its still wise to tune a proper intake for times when you're not under boost. I guess what I'm saying is, since intake design has little to do with performance during boost, but a lot to do with performance off boost, design it for the naturally aspirated engine so you have the best of both.

[T66]

Originally Posted by zagrot

it appears that you have great metal fabrication skill, the intake looks good. i went digging through some of the stuff that i found when researching intake manifolds and subwoofer design, you'd be surprised how similar the two subjects are. here is some stuff that is actually usefull.

this one is a good reference:
http://www.grapeaperacing.com/GrapeA...ionsystems.pdf

though i don't think you need guidance with the metal work aspect of fabricating a manifold, this site has pictures of the fabrication process. note the use of velocity stacks at the end of the runners.
http://www.themininut.com/inlet.asp

also since you said that you plan to install some type of forced induction device the manifold specifications will be less critical, though a tuned runner length would be beneficial. you would probably have been more pleased with your creation if a turbo charger, i'm asuming, was already in place.

Thank you very much. Yip, by forced induction I mean the Turbo route, the only route!!!!!!!!!!

[T66]

Originally Posted by curtis73

I agree 100% with zagrot, but I wish to add something. The construction of the intake is less critical with forced induction, but only under boost.

For instance, if you construct an engine designed for low-rpm power but use a large, short-runner intake, you'll have sluggish performance. If you add a turbo tuned for high rpm boost, you'll have an engine that is frustratingly sluggish until boost comes in.

Although the intake design has less importance under boost, its still wise to tune a proper intake for times when you're not under boost. I guess what I'm saying is, since intake design has little to do with performance during boost, but a lot to do with performance off boost, design it for the naturally aspirated engine so you have the best of both.

You guys are rocking.

[superchuckles]

one thing i haven't seen mentioned, & it can make quite a bit of difference, is port matching. not just between intake & head or head & exhaust but also port matching your gaskets. ideally, you can get all your ports to equal sizes between cylinders for equal flow, but also, matching the mating surfaces of the intake/head so that the openings are precisely the same shape & alignment, AND trimming the opening part of the gaskets so that the transition from intake, across the gasket, to the head, is a completely smooth one. granted it is a time consuming task, but one that yields an engine that doesn't have as many "quirky" spots across it's rpm range.