I was wondering what differences I might find between the 272/272 cam set up vs. the 264/272 set up. I got a really fantastic deal on a set of brand new 272/272 cams, but heard some bad things about the idle. I found a vendor willing to sell me just a 264 intake cam, but then I am spending an additional $300.00. How bad is idle with the 272 set up compared to the 264/272. What about performance differences between the two?? Thanks for any insight you can provide!

 

Performance #s on all the HKS cam combos are pretty much identical. If you want a setup that doesn't have a lumpy idle, get a 272intake 264 exhaust combo. It is what I am running in my car right now. Makes great power. The only time the idle is somewhat lumpy is just on coldstarts before the motor is warmed up, and even then its not bad.

 

I run a straight 272/272 setup with Vishnu adjustable cam-gears set to -4/-1. Slightly lumpy idle with AC off, smooth with AC on, never stalls. This setup gets a very big from me

l8r)

 

how much of a power increase are you getting out of the cam upgrade?

 

Here's a combo of my 3 dyno sessions... What you're basically looking at is stock vs Vishnu stage 1 vs Vishnu stage 1+. However, keep in mind that the Stage 1 dyno pull was done on 91 Octane and in CO, whereas the Stage 1+ (272 cams) pull was done in Chicago with 93 Octane.

Going by the ole butt dyno, however, there is noticeable improvement after 5000rpm until redline. Even with a stage 1 (stock cams) tuned to 93 Octane, the car would start to run out of steam past 6K or so. Now it pulls very hard past 7K, with peak torque at just below 5000rpm



l8r)

 

Great graph - wow, what an increase in power.

Question: Was this Stage 1+ run done with the 272 cams timed as you indicated above (-4/-1)?

 

Thanks a lot!! I will stick to the 272/272 set up. I got a chance to sit in another Evo with 272/272 combo, and I did not find the idle to be too bad. I have to say when he took me for a ride all I could do was !

 

Yep.

l8r)

 

If this is the case, then it is significant where cam timing is concerned. I don't have the stock cam timing events, but here are the overlap settings (at 1mm) for HKS cam combinations:

HKS 264 set (9 deg)

HKS 264/272 (13 deg)

HKS 272 set (17)

HKS 272 set at -4/-1 (14 deg)


So basically, with the above cam timing, the 272 gives roughly the same overlap (one degree more) as the 272/264 combination. This setting must be significant, as even as low as 2000rpm, it looks to give some 30 ft/lbs greater than the stock configuration, and this figure jumps to an 80 ft/lb difference as low as 3000rpm.

This leaves me with little doubt that the -4/-1 setting is THE ticket to running the HKS 272 cam set on the street.