GenVibe - Community for Pontiac Vibe Enthusiasts

I see a lot of Short Rams on Ebay for the GT, but none for the Base. Is there a difference?

yes. there is one more vacuum hose for the GT then the base, but i believe you can use a GT system on a base, but not the other way around. someone correct me if i'm wrong.oh, and welcome to genvibe.

BTW, at least one Viber (me) thinks short rams aren't nearly as good as long ones, and should be called HAIs (Hot Air Intakes), since they pick up hot, thin underhood air, which costs ~ 5% power vs. cold air...

Quote, originally posted by MadBill »BTW, at least one Viber (me) thinks short rams aren't nearly as good as long ones, and should be called HAIs (Hot Air Intakes), since they pick up hot, thin underhood air, which costs ~ 5% power vs. cold air...i agree w/ that statment, madbill. from my reading here on this forum and consulting w/ other modders.. there is a big diff b/w short ram and full cai.

Quote, originally posted by MadBill »BTW, at least one Viber (me) thinks short rams aren't nearly as good as long ones, and should be called HAIs (Hot Air Intakes), since they pick up hot, thin underhood air, which costs ~ 5% power vs. cold air...I also will agree with MadBill on this one. If you're going to go with an aftermarket air intake, it's worth the extra $ to get the CAI. Unless, of course, you are planning on placing the inlet of the short ram intake up in a hood scoop.

I think the throttle bodies sit at different angles which creates a difference for the short ram. Somebody correct me if I'm wrong.

Yeah MadBill, what do ya think about what ebslopp posted? I was thinking of getting the SLP hood with the twin air scoops and putting the short ram intake under the scoops if possible. Do you think that would work?

yep, that'd be the only way for me to do a short ram system. to have the ram air hood that let cool air flow over it.... but then it'd be sooo expensive, still not worth it!

Yes, as Hope says that would work great, but with paint and parts would likely run close to 1K...

Personally, I don't really car for hood scoops. I think they ruin the look of a hood. Go with the CAI. You get more bang for your buck. Or if you want the most HP per $ go with the supercharger.

Quote, originally posted by ebslopp »Or if you want the most HP per $ go with the supercharger.Still really too much expensive for me...

yep, you can get a cosmo full cai for about $120 USD. best price and product from my understanding if you don't want to go name brand.

I wouldn't concern myself so much with CAIs vs. short rams. The power comes from eliminating the restrictions of the factory box/piping more so than temprature.

Err... Not quite, Fusion! Much of the gain does come from eliminating restrictions, but each 10 degree F. drop in temperature is good for a 1% power increase, not counting any possible resultant reduction in detonation and hence spark retard. I measured the temperatures where a typical short ram picks up it's air and at the inlet of the stock system, just behind a hole in the radiator support. I took readings both idling in traffic and at various speeds on my base Vibe last summer and found that while the stock inlet temp was less than 10 degrees above ambient, the short ram inlet point was as much as 55 degrees higher, thus costing almost 6 HP on a IZZ.BTW, usually when a car is dyno tested the hood is left open, so a short ram would get unrealistically cold air.

What was the temperature difference at slow speeds Madbill? I can fully understand the 55deg. difference at idle, but when the car is moving, you should see less of a difference, right?I don't want a CAI because I don't want to deal with the hassles of getting to the filter for maintenance. The main reason for the short ram is for some additional hp during accelerations in 2nd and 3rd gears.

OK Bill,Get on a chassis dyno in a temprature controlled cell and prove it.

Quote, originally posted by rocstar »What was the temperature difference at slow speeds Madbill? I can fully understand the 55deg. difference at idle, but when the car is moving, you should see less of a difference, right?I don't want a CAI because I don't want to deal with the hassles of getting to the filter for maintenance. The main reason for the short ram is for some additional hp during accelerations in 2nd and 3rd gears. Yes, idle was the worst, but even at 50 MPH I recall the difference being over 40 degrees. The numbers are in a post of mine from last summer, will try to track them down.On various other vehicles, I have seen set ups where the filter was in the engine compartment, but either fed by a duct from a cold intake source and sealed around the filter or walled off from engine heat by a baffle.

>Quote: OK Bill,Get on a chassis dyno in a temprature controlled cell and prove it.End QuoteHey, I stand by the physics on this one, Fusion! "I doan' need no steenkin' dyno!" (Athough depending on where in Michigan the town of "Look at your Vibe" is located, maybe we could meet at a dyno somewhere to verify the issue. Loser pays for dyno time, winner buys the first round. ) The gas law PV =NRT tells us that the density of a gas is directly proportional to its absolute temperature, so if the temp goes from say 70 F. (530 R.) to 120 F. (580 R), then the air density and hence the power drops to 530/580 x 100 = 91.38%. This equals a 1% loss for about every 6 F. degrees, but in an engine more charge heating occurs in the inlet runner and port with colder air, because of the greater temperature difference, so the 10 degree rule of thumb is a better predictor.

Bill, if I take another physics class next semester, could I email you my homework and projects to do for me?

Ha! 37 years after my last physics class, it amazes me that I can remember even the bits that I care about!

The Vibe is from Pontiac, thus I live in Pontiac MI. I've got enough academic and practical experience with all this to know what's going on, but I don't feel the need to cred drop. Pressure, velocity and cylinder fill all play a part. The MAF sampling is another factor. You're only looking at temprature.