*Delta Cams* 272 Intake, 264 Exhaust, what's the deal?

[jjrock5]

Well as I type this I have in my fresh engine a set of the Delta cams stated in the title. As Ive been talking to people they tell me that the 272 cam should be in the exhaust NOT the intake, and it makes sense to me (try to get the gases out asap).

Well I knew this before I got the cams but when I talked to the guys at Delta they told me that turbo applications call for 272 on the intake and 264 on the exhaust BUT their logic was the same, 'try to get the gases out asap' and they told me that this setup would do that. and that 264 I/272 E would NOT be as efficient in doing this as the way they recommended. Now idk if my cams arent as efficient as they should be since I may have the profiles backwards. When I talked to them I told them, just do the 272/264 setup that is best for turbos and Ill trust your judgement (since they deal with cams all damn day!!)

What do you guys think?

 

[TSIMonsteR]

This use to be real big back in the day. I'll see if I can search through some old threads and find something to help.

 

[jjrock5]

Thanks thatd be cool. I searched as well but all I found was ppl running the 'normal' setup, which is opposite of what I have.

 

[e85_4g63]

Not sure why they told you that the reasoning for the 264/272 combo was to "get the exhaust gases out asap" but that isn't why you run that combo. The reason you run the 264 on the exhaust (smaller then intake) is so the turbo will hold boost higher into the rpm band. This is especially helpful on the 2g cars (because they have smaller ports). Smaller ports keep velocity up (which in turns keep the torque closer to HP for a more streetable power band). If you look at the difference in lift and duration compared to the stock cam, and take some time to think about it, you'll get the idea. The purpose is to keep the turbo holding boost higher into the RPM range for a "smoother" power band. Not sure why your profile isn't filled out but if your still on the stock turbo this will help hold boost longer.

 

[jjrock5]

Let me ask you a ? if I switch to 272 E/264 intake will the idle lope be less than the other way around? At this moment the lope is noticeable (stock gears) and I thought this combo was supposed to sound very much like stock if not the exact same.

Profile updated BTW

 

[chanley talon]

I'm going to be contacting delta also to grind my cams. What should i have done? 264I 272E or 272 I 264E . I like lope! I want it NOT TO sound stock as much as possible. Thanks!

 

[jjrock5]

YouTube - DSM GST, FP T28, Delta 272/264, 3 in downpipe, no cat, Thermal catback exhaust, fresh 7 bolt

YouTube - dsm gst vibrant exhaust with resonator fresh 7 bolt

Heres my car with two diff exhaust setups. Maybe youll like the lope. The 'normal' way is 264I/272E but I have 264E/272I and thats what the vids show.

 

[GalantGreg]

I like the the sound of the 2nd video. What is the cam setup on that one?

 

[chanley talon]

I like the first video best . I don't know why people don't like the cammed sound? I think it sounds like it means business! Are these delta cams? I'm going to go with the 264i and the 272e . I think with the exhaust valves being small that this will equal out the flow.

 

[e85_4g63]

I have there 272/272 combo. If you don't mind me asking, why are you guys interested in the 264/272 combo instead of just going with 272's on both sides? To jjrock5, thanks for filling out your profile, that helps us alot when giving advice on things. If your planing on staying with that T28 for a while, then I understand why you'd want the smaller cams, but to be honest, you would've seen better results with just straight 264/264 combo with your setup. What does your car idle at? Do you have the AEM W/B o2 hooked up yet?

 

[chanley talon]

The Dyno charts show that the 264/272 set up makes just a little bit more torque and horsepower than the 264/264 . When you go 272/272 you lose torque. But gain like 1hp over the 264/272 when running to 6800-7000 rpm. So it seems for a good street setup up the 264/272 combo is ideal. I have an automatic so i am concerned with low end torque as well as top end power. http://www.automotosports.com/cam_test.asp

 

[e85_4g63]

If your concerned with making more torque then HP (or making power sub 7K rpm's) then go with the 264 / 272 combo, keep the stock 1g intake manifold and T/B. The longer runners on the 1g intake manifold favor a wider torque curve.