Are there any downsides to a greddy intake manifold?

I got my hands on a topspeed (greddy counterfeit) intake manifold for my s13 sr20det for free and I've been wondering whether to put it on or not. My motor is still pretty much stock with the original t25 turbocharger. Somewhere I read that it isn't good to put on the manifold with the stock turbo but gave no reason why. I think with the anemic stock turbo, I shouldn't even expect noticable power gains but I was just wondering if anyone knows if it could cause any problems for me if I do put it on (or changes in fuel economy).

this is a crapshoot... im assuming the new plenum is bigger than the stock one... maybe something to do with more air coming in while the same amount is leaving? just trying to use common sense.. i dont know too much about that stuff so thats the best i can do for you..:2cents:

Sell that bitch, since you got it for free it's 100% profit.

I'm going to be in the market for an upgrade turbo setup once I get a new job. I was planning on eventualy getting a manifold anyway when that does eventualy happen. I can't see myself shelling out the extra $300 for the actualy greddy manifold so I was planning on holding onto it. However, I was just thinking it would be nice if i could get a small power upgrade and top access to my oil filter in the meantime.

Topspeed mani eats shit.

China casting is porous so eventually oil and crap leaks through it.

People are talking about the intake manifold will gain power where the T25 is already choking. if you put the manifold on it won't help much since the T25 can't flow enough air to show gains where the greddy would be helpfull making the power.


Cams and a 2871R minimum.

Topspeed mani eats shit.

China casting is porous so eventually oil and crap leaks through it.

People are talking about the intake manifold will gain power where the T25 is already choking. if you put the manifold on it won't help much since the T25 can't flow enough air to show gains where the greddy would be helpfull making the power.


Cams and a 2871R minimum.

if you got oil in your intake mani, you got issues :P
I can understand what you're saying about quality, altough I'd doubt that air will leak through casting (or oil in the oilpan's case).


but I agree about the cams/turbo (injectors/tune) thing before putting one on.

unless you fab it, you have to buy the greddy coldpipe going from the in mani to the intercooler, this is what they say anyhow...

The piping is not an issue for me. As I said earlier, I plan on upgrading my turbo setup (with cams to match) sometime in the future. Since the intake manifold is not a wearing component and I plan on having one on there when I upgrade my turbo setup anyway, I would like to put it on sooner than later if it does not negativly effect my cars performance in any notable way. I know the manifold is ideal for a larger turbo but Im not exactly clear on what you're saying it will do to the t25. Are you saying that I will have problems with less restriction in the intake manifold because the small stock turbo will have trouble increasing pressure in the system because it cannot move a large enough volume of air?

you shouldn't have any problems, but don't expect crazy gains, I have seen sr20det's with them and stock t25's and they didnt seem to have any problems, I have also seen them on s14/s15 motors with a mostly stock motor (well s14/s15 mani is a bit diff) and turbine and they ran great.

in theory you'll lose power across the entire RPM band, the intake manifold will cause losses in the low end, and the T25 is already choking by the time the intake manifold will want to gain power.


it won't help, but its not really hurting anything.

which one of you is the real rw240?
pants or lol?