Piper Cams Installed

[raygr]

With mixed results. More torque < 6000 rpm, but loss at high rpm. Anybody have any ideas? This is the Piper BP270 cam set on a 2006 Exige. The dyno below is before/after cams. Other mods in both runs: FF street header/cat, Larini Exaust, ReVerie intake.

[Boosted2.0]

Isn't the cam phasing between small and big lobe on the pipers non-staggered? The stock cam has like a 15 degree advance on the big lobe versus the small one, thats why the pipe has less dip at lift transition - you probably need a standalone to tune it properly and take advantage of it

[raygr]

Originally Posted by Boosted2.0

Isn;t teh cam phasing between small and big lobe on the pipers non-staggered? The stock cam has like a 15 degree advance on the big lobe versus the small one, thats why teh pipe has less dip at transition - you probably need a standalone to tune it properly and take advantage of it

Why wouldn't the Piper big lobe not contain the same phasing as the OE cam? Maybe I'm not following you. What would you tune if you could?

[shay2nak]

you lost HP on the 2nd cam?

[choi0706]

Originally Posted by raygr

What would you tune if you could?

everything..

[Randy Chase]

Keep in mind that all the bits work together.

When we tested with cams, we found certain headers and intakes lost power.

[raygr]

Originally Posted by Randy Chase

Keep in mind that all the bits work together.

When we tested with cams, we found certain headers and intakes lost power.

When we dyno'ed before cams, we found the FF headers made power. I suppose it could interact badly with the cams, but who knows?

Also, Piper claimed that this cam set (BP270) did not require ECU tuning - it should work with the stock ECU. Of course, tuning would help. I would love to tune the ECU, if anybody comes out with something that can be tuned.

[Randy Chase]

There are tunable ECUs coming. Stay tuned for more info.

Things can interact differently. What works with one set of cams, can be different with another cam. It all gets so involved trying to test all the combinations... but suffice to say that these things are all integral to each other and one thing will change the performance of the rest. It is not a case of this thing adding power, so then add that thing and the other thing.

[Randy Chase]

I can tell you that my cams, gave me a lot more power in the midrange... but also more power at the top end.

[MikeW]

Sleepless had piper cams and had a similar experience. The power was down on the 2nd cam but increased on the small cam. He had other issues but did do a before and after cam change dyno graph. It was the 270 grind. I would fax or email your graph to Piper for their opinion.

[raygr]

Originally Posted by MikeW

Sleepless had piper cams and had a similar experience. The power was down on the 2nd cam but increased on the small cam. He had other issues but did do a before and after cam change dyno graph. It was the 270 grind. I would fax or email your graph to Piper for their opinion.

Yes, we are going to follow up with Piper on this.

I think Randy has the 285 cams, which Piper claims required ECU tuning.

[Boosted2.0]

Originally Posted by raygr

Why wouldn't the Piper big lobe not contain the same phasing as the OE cam? Maybe I'm not following you. What would you tune if you could?

The seperation in lobe phasing on the stock cam is very undesireable for forced induction applications - its what causes that big dip in power at cam transition. I would assume thats why it was done away with - that or nust because its too hard to buld them like that - /shrug

If you want more NA power I would try advancing the intake cam position in lift, and increasing ignition timing. Also drop in some Denso IK22 plugs to ward off detonation with the increased timing.

[Boosted2.0]

wait - that cam is only 270 degrees of advertised duration?

[MikeW]

Originally Posted by raygr

Yes, we are going to follow up with Piper on this.

I think Randy has the 285 cams, which Piper claims required ECU tuning.

I'm glad you're letting us know your experience, good or not so good. I think you're going to need more info about your a/f . You need to know if the engine is definitely leaner on the new cam, especially the 2nd lobes. As far as the a/f on the stock small cam, mine was lean as hell and the ratio got fatter with more revs. It makes me wonder how a larger small lobe profile makes more power at all.

slight possibility the bigger 2nd cam isn't too happy with the springs. Better be a little persistent with piper about them being adequate.

[Boosted2.0]

The stock cams on a 2ZZ in a celica has a 276 degree advertised duration with 10mm lift on the high speed lobe for exhaust and 292 degrees of advertised duration with 11.2 mm lift on the intake cam.

If that Piper cam has 270 degrees of duration on the intake thats actually a smaller duration than the stock cam by a considerable margin - whats the lift on it?

[Boosted2.0]

These are the specs srraight out of the 2000 Celica new car features guide:



If the 2 sets of numbers are confusing you for open and close they represent maximum retard and advance on the VVTi

[MikeW]

I got 288 intake/284 exhaust advertised. They don't say how they arrived at the figures. Search "Piper". Where has my power gone/sleepless.

[Boosted2.0]

well if you're buying a cam with a smaller duration than stock I would expect it to loose power on the top end. You should also be able to tune it for a much earlier cam transition with zero dip using a standalone

[Boosted2.0]

Also who installed your cams, and did they know to make sure the exhaust dot is a tooth and a half CCW from the intake dot? If not your exhaust cam could be a tooth advanced.

[Boosted2.0]

Oh - looks like I was off on the phasing - its a 25 degree difference in intake phasing and 26 on the exhaust. Its been a while since I looked this stuff up - anyone have a link to pipers specs?