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I can't believe that there aren't gains available from larger cams...call me crazy, but here are the factory specs:

BNR32 RB26DETT Solid

Intake duration 240°

Exhaust duration 236°

Intake lift 8.58

Exhaust lift 8.28

Preset valve timing INTAKE 113°

Preset valve timing EXHAUST 125°

And here are some Tomei "drop-in" examples:

Type A

Intake duration 260

Exhaust duration 252

Intake lift 9.15

Exhaust lift 9.15

Type B

Intake duration 260 (same intake as type A)

Exhaust duration 260

Intake lift 9.15

Exhaust lift 9.15

* Type A
Designed to best suit the stock & N1 turbos for optimum performance balance of low to mid range torque.
The Exhaust cams duration was reduced to maintain best idling.
* Type B
By extending the duration timing compared to the Type A Poncams, both response and peak power was raised and these camshafts best compliment the mid to large size turbo charged applications.

How can one say that they won't make more horsepower with more duaration and lift? surely this is a myth?! Perhaps the gains aren't there with some turbo / valvetrain setups, but I assure you there will be a powerband difference between STOCK, A and B in nothing more than lift alone.

Now, does everyone have the mods to support the flow / overlap? Who knows.

My experience with streetcars with turbos and cams, stay on the small side of duration. I chose Poncam A's for my 2.75L stroker motor with ported head, +0.5mm SS valves, retainers, springs, etc. Just wanted a touch more duration and lift than factory. I won't be able to tell you what they do different, but then again, I'm pretty extreme on setup with BW 8374EFR turbo and all.

Edited by HarrisRacing
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Change the cams when you change the capacity of the engine or you are going for a hell of a lot more power then the -9 will ever make

R34 brembos can be made to fit you just need to drill out the holes on the r32 front hub so that the bolts fit thru

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You are right there will be a power band difference it all move to the left and causes the car to drive worse then it needs to for the power they give, the other issue with all these "drop in" cams is they never have enough lift for the increased duration, which causes them to lower dynamic compression even more then a properly designed cam shaft

We have made the mistakes of using all these parts and know first hand what their benefits/flaws are, a lot of people get caught up in the fact they fitted these pieces of junk and made 5-10kw but forget they lost 20kw out of the bottom end of the rev range where you spend most of your time actually driving the car

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