regarding piper 285 dialing in

[chipis]

would like to know how did you dialed this piper 285 in your engine. im interested especially in overlap. im having camshaft vernier pulley so i cannot see on it when it is zero degrees on it, because it is not marked on it. at the time at TDC im having about 0,9mm inlet valve open and about 0,2mm exhaust valve open. how much overlap have you dialed at the tdc and how much boost and bhp ar you running with it? asking because i have some worries that i have dialled it wrongly and cannot reach 200bhp line with a lot of boost

[Sparkie]

you can't change overlap by changing the timing.
its ground into the cam.
you can mess with the advance and retard though....

[chipis]

yes you are right, would like to know how other members has diaed theirs piper 285 cams at the top dead center.

[Scoff]

it sounds like you have a 2 or 3 degrees of advance at the moment. Try it symmetric or with some retard. Optimum cam timing seems to be engine specific but usually some retard will help make the numbers at high rpm.

[chipis]

as how i think, i should have almost the same lift at tdc for intake and exhaust valve?

[chipis]

so no one has piper 285 cam or no one wants to share its secret information about how it is dialed in? :)

[Sparkie]

assuming the cam is designed to be at 112deg - retard it by 4deg to move the torque up the rev range.
tappets at 10 tho inlet and 12 thou exhaust.

what else do you wanna know?

[GTphil]

My 112 degree piper 285 is retarded by 4 degrees, most definatly gives me more power high up the revs, my car did just under 107mph terminal speed at Santa pod with 22psi boost from a t28, thats an honest 200hp. I also run lower than standard compression.

It's pretty flat low down the revs off boost, I rev it to 7k but it feels like it wants to rev more.

[Alex]

My 285 is dialled in @ 114 degress running 15 psi on a T2/T25 turbo with standard pistons, but the engine has a lightened/balanced bottom end and a flowed head etc.

It's nice..... :D

[chipis]

can i run piper 285 with stock with stock cam pulley?

[Alex]

Yep, but I'd make sure you check the timing :agree:

[chipis]

so the timing checking during alignment of cam puley and crankshaft pulley, what else can be wrong if it is aligned well?

[Jonny5]

My 285 is dialled in @ 114 degress running 15 psi on a T2/T25 turbo with standard pistons, but the engine has a lightened/balanced bottom end and a flowed head etc.

It's nice..... :D

Andy idea of what power you're making with that setup alex?

[Alex]

so the timing checking during alignment of cam puley and crankshaft pulley, what else can be wrong if it is aligned well?

As long as the timing isn't miles out with the standard pulley (some of the cams are waaaaaay out!) then all will be well :agree:

[Alex]

Andy idea of what power you're making with that setup alex?

157 BHP and 181 LB on the WGT hub dyno :agree: It's not just about the figures for me though, it's the way the car delivers it. My set up seems to pull really well, especially out of corners. I suspect if I went for a full T25 it'd be better again, especially at the top end :)

[Nottswoody]

157 BHP and 181 LB on the WGT hub dyno :agree: It's not just about the figures for me though, it's the way the car delivers it. My set up seems to pull really well, especially out of corners. I suspect if I went for a full T25 it'd be better again, especially at the top end :)

But this worries me as I have a standard engine and a t25 an I got 154bhp at nd :scratch: I think something is a miss here bud.. I'm putting a cam in over winter but was hoping for much more..

[Alex]

At what boost? My engine does have quite a few mods internally plus the 285 cam. Also different rolling roads will give different readings..... :)

[Nottswoody]

A sneaky 1.2 bar leaves a little bit to play with but I wa lead to believe with a cam it would be closer to 200?

[Alex]

I think you'll struggle to see 200 BHP with your spec to be honest, I think you'll need the cam + more boost. As ever it's all in the tune - turbo/cam combo (timed in correctly) boost and AFR to name but a few. 154 BHP seems o.k to me really :)

[Nottswoody]

I was told the t25 is good for 24psi but I could always go t28 if needed see what happens after Iv built the engine it's going to take a little while though due to asking the wench to marry my ass :) but I'm aiming for next yrs nd..