Thread: Cams for Ve-t

um yes maybe that's why i put my input in. i am not stuck in a box

So have honestly tried running a cam with 280* duration, 70* overlap on a T28? What was the setup? Did you make more power? Any results you can post up?

I seem to be the only person who has dyno compared the VET cams vs the stock 2.0 cams. There was nearly 100whp difference on my setup.

GT3076r .63.
Protech redesigned Log manifold
8.5:1 compression.
3" exhaust.

15psi




VET cams 1 year later.

Facts are always best...

Coheed, did you compare both VET-cams to both SR20VE Cams?
Were the shifting points the same?

Yes. I didn't bother making a hybrid cam swap and dynoing it. On the old graphs I believe the switch points were around 5000 or so. I may have kicked it earlier though I really can't remember that far back.

The last dyno you can see where the graph starts to take off again after switching the intake cam.

I tried switching the ex cam on the VET but it also seemed to lose power, just like in the stock cams. The stock cams with 48* of overlap had horrible reversion issues. I could actually feel the car choke up when switching the exhaust cam on the stock 2.0 cams with the log manifold.

Which is why I went with a Twin Scroll setup. With TS you are not likely to see reversion. The seperation between firings makes it nearly impossible for a pulse to contaminate the air charge. High backpressure can still cause a big loss of performance though. And the bigger the cams, the less backpressure you want.

Of course you could have too little backpressure as well. This will cause your fuel mixture to go into the combustion chamber, then quickly exit out the exhaust during the overlap period. Ya, you don't want that either.

Best place to start to get the best performance... log backpressure VS your boost pressure. If you can get slightly over unity, but not too far, the gains are rediculous. Go too far though, and you run the risk of dumping raw fuel in the exhaust.

Getting equal intake pressure with exhaust backpressure is a good place to start getting the best performance from a cam designed for NA applications to start. NA engines perform with close to equal intake pressure and exhaust pressure. I would say that is the best place to start, but what do I know?

interresting....80whp ist a hughe difference....

and the 444hp@25psi you also made with VET Cams but different turbo/manifold setup?

I made 442whp with 349wtq on that same exact setup on 24psi. The turbo seemed to have maxxed out on the log manifold, so I decided to upgrade to get more power.

I ran the VET cams even when I put the tubular manifold on. The cams are very loud. They seemed to spool the turbo a lot quicker, but the stock cams have the push on the top end. When the 2.0 cams kick in at 5500rpm you feel it kick you back in the seat. It was a completely different animal than with the log manifold.

Despite the fact that the 2.0 cams have better push, the VET cams never surged the turbo, even though they spooled faster. The new cams push the turbo into surge in 4th gear because they can't flow enough on the bottom end when the turbo really wants to take off.

precious info coheed, are there updated dyno-prints to visualize this "kick in the back when shifting" maybe it only feels like that because its much weaker in the low lobe in comparison to the VET? Or are your sure that top end power is defenitively better with the stock cams with the TS tubular?

Another idea: What happens when you shift the exh high lobe on the VET cams with tubular manifold ( i think nobody tested that before?)

facts are great and i do agree with the vet cams but i disagree with sr20ve cams being best for a t28 i lost the motor before i had any chance to dyno it and i am going with a bigger turbo now but i can tell you this i felt a difference up top with n1 cams on a t28

I have some dyno charts posted in some of my other threads. The VET cams seemed to spool quick but didn't make as much torque as the VE cams did once the tubular was on. The VE cams make a ton of torque at 5000rpm. I went from 349wtq to over 400wtq just changing the manifold, housing, and cams. The top end suffered because of a weak engine.

There is a possibility the VET cams perform better all-around, but I didn't ever dyno on the VET cams with the tubular. Just driving around. The 2.0 cams have a very noticeable kick when they switch. It was so much fun I couldn't get rid of them. 5000rpm switchover and you actually feel the car pull harder.

With the VET cams I had to wait until 6000 to 6500rpm to actually feel the cam switch, and it wasn't as big of a kick.

Actually no. It is a modified Pulsar manifold with an external gate.