Thread: Think I went with too big of a turbo...

nevermind, found it.

A thing you need to think about. On a proven good flowing setup, large turbine housing, equal length, large runner tubular manifold, port matched to the head, and large free flowing exhaust its proven the SR16ve cams are great cams for boost and make great power, Really helping on spool time as well with larger turbos which is a great benifit.

The key is to keep the backpressure lower than the boost pressure. If you can do this during the overlap your boost pressure will actually push heat out of the cylinder and help cool the cylinders down. If you have more backpressure than boost, this cannot happen.

I think thats why my 60 trim with the .82 turbine housing did soo well even at 30 psi of boost on a calum basic that i fine tuned i had no detonation or hotspots anywhere even with the crappy 100 dollar rwd short runner topmount manifold. The large turbine really helped keep the boost pressure higher than the backpressure.

I think when I went to the 67mm turbo and the C2 cams and tubular manifold it was a really good flowing setup and the Cams proved that as power was still on the rise all the way to 8700 rpm. Never did it even flatten out. Still going up. Cams pulled great. other issues with lean and over advanced timing caused issues with that but even then after I took the head off still no hotspots on the pistons or anything. Just the obvious detonation damage on the head and valves as egt's went way up from the overadvanced timing and lean mixtures.

There are keys to making every which setup work. Since your setup Vadim is impossible to keep the backpressure lower than boost pressure you need to have a cam that has little overlap to keep the heat down in the cylinders.

I think the VET cams are your best bet for sure if you want to keep your current setup. And i think its a great setup for what your looking to accomplish you just need to get the right parts together.

My old protech.



Turbine AR, trim, and overall size are major contributing factors to how well the manifold will work as well. My 84 trim T31 wheel flows quite a bit more than Vadim's wheel.

Can you post a video of the turd VVL when it kicks? Have it kick at 6000 and see if it does anything to the speedo.

Oh snap! I found my dyno of the .78 housing with tubular and VET cams!


This dyno was only (correction) 13-14psi.

Here is my dyno at 10psi of the tubular, sr16 s/r setup.
Green line is 10psi, 13-14 on the others. Played with timing on the red line.


Slight timing change aside, I would say the VET cams made very good power compared the the 1.6L cams.

Maybe it's the design of protech's that sucks so much?

I'll try to get a video up, my car is sitting in the garage because the Spal slim fans I bought where bigger anticipated, and I have no time to try to fit them. Basically what I'm getting to is, if these slim fans don't cool the car enough to have AC in dead stopped traffic, I'm saying bye bye to the turbo and going NA. Spent too much money to keep this car cool and it still fails miserably .

Once she is running I will do a video of 4k cam switching like I've been having it, and then will try to 6k for the first time. Gotta raise the redline to 7500 too.

n/a > turbo? !

This thread could provide much needed proof!

(see how I left it open ended for both sides? ahthank you.)

pussy

salty (we are describing one another, right)

Mr stock boosted car

factory boosed! get it right!

Another thing I'll try out is running just one high lobe cam.

If I use the intake cam only, it's 28* of overlap, if I use the exhaust cam only it's 20* of overlap. Looks like Coheed only dynoed the intake cam on without exhaust cam. Not Exhaust without intake, so it's worth a shot. As a temporary solution.