Intake manifold comparisons
 

I've been doing a little reading and wanted to get some people's opinions about some different intake setups.
The car I have is a s4 NA. What I'm curious about is, assuming I have a true dual exhaust, (the RB setup, header back), and stand alone EFI, which intake is going to give me the best gains? Or, the best gains for the buck, at least.
I saw a previous post about converting to a s5 intake, which got the guy like 10hp over the stock s4 one, but was also curious about hp increases people were seeing from EFI weber and holley setups.
Is either the weber or holley EFI setups worth the money in terms of hp gains over a s5 setup, or would you need porting to take advantage of the aftermarket intake?

For a stock port, the weber efi system is overkill. While you might see a small gain, its not nearly enough to justify the money for a whole new intake system. You would probably see some gains from an s5 intake, but again, probably not a whole lot with a stock port. Remember that the stock s5 engine only made 14 more hp than the stock s4 engine, a good bit of that was from the higher compresoin rotors.
I would like to see what kind of gains people have gotten from aftermarket ITB setups with a street port. I'm looking at doing that on my car down the line and sould like to see some numbers. I haven't found any yet, but I might be looking in the wrong place.

i have a street ported S4 TII and i would like to know also what kind of gains people were getting outta different intakes....

also what about using the 3rd gen intakes is it possible and would it be worth it someone let us know

thanks

You can have a small gain (3-5 h.p.) from using an s5 upper intake on a s4 lower, but you will need to elongate the outer mounting holes. Everything else lines up. The s5 took advantage of slightly longer runners, which helps with acceleration of pressure waves and bottom end power.

Technically is has longer AND shorter runners from the VDI.

Meh. Do you like torque? If yes, go with the S5 NA manifolds.


Do you not care about torque? Do you want a top-end that never runs out of breath? Remove your aux sleeves, port match an S5 turbo LIM, and an FD UIM to match that. Now you have an intake that would be 6port turbo friendly (easy to setup) if you have plans of ever going that route, and you will never run out of breath. Perfect for ported, and stock port, motors.

I think you can tell which one I'm setting up.

That is true Sideways7.....I was thinking about a tII upper intake and forgot he mentioned he had an n/a.

That wont work unless you use 4-port turbo irons.
Your best bet is to use the s4 lim and tb and s5 lim, its the best of both worlds. First off, that gets the best power, and keeping the s4 tb means you can keep the mechanical omp. The s4 lim means you can keep the exaust operated aux ports and dont have to run an airpump or mess with electronic activation.

After searching around more, the full s5 intake conv. doesn't seem like a good idea. I read in someone's conversion write-up he dyno'd a 10hp gain, which is why I thought about doin it, but can't seem to find it now..
Icemark posted some useful info about it also, so based on that I'll probably just stay with the stock for awhile, then use a holley style TB with my stand alone eventually. Main reason I wanted to was at some point in the future I'll put a ported motor in and it'd be nice not to worry about ECU mods at that time, just retune.

you need to work more on those mad driving skillz. when are you coming back to the ville? mine is finally alive. tiny and i are finding some nice places for drift sessions on the weekends.