intake manifold: sheet metal vs cast

[greathuskie]

ive done a bit of reading about both, which one would you rather have and why?

they both have their strong points, one question though (im just wondering) is it possible to run direct port nitrous on a cast manifold? i would think it would be easier on a sheet metal intake because of the length of the runners but what do you think?

[autronicDSM]

Length of the runners depends on what RPM range manifold is designed for. So if you want to run direct port nitrous you can do it on either one, you still end up drilling holes in either one. Cast manifold will obviously have less rough edges then sheetmetal just because there's no welds. I think you should look at where manifold improves the flow and makes power and not from what material it's made of.

[kilurv8]

The only cast Intake Manifold is the one that Dale Forrester makes and who I am a big proponent of. His manifold actually comes with NOS bungs that have been predrilled and tapped for direct port (comes with plugs if you do not want to run NOS right away). Sheet metal is difficult because you have to get bungs welded on then tap them where as with the cast manifold, you can drill and tap anywhere for vacume taps, intake temp sensors, map sensors and the like. The rest of the decision is up to you and of course I am going to suggest Dale's manifold becuase I have one and helped him develop it. I have seen it do some major improvements on many cars and even great improvements on 16G powered cars. Let me know if you have any more questions.