Piper Cam Selection

[bju90]

Has anyone fitted a set of the ultimate street or rally cams from Piper to an NA engine and can comment on the results they saw?

I am looking at a simple NA build for circuit racin: 8k rev limit (stock bottom end), 2017 intake manifold (limited to stock manifold by regs), EL 4-1 headers, mild port/polish to clean up the stock castings, cams, valve springs. Was thinking the SUBFA20BP300 ("Rally" cam) but unsure if this might be too aggressive.

I have been in contact with Piper but they seem very reluctant to provide any selection advice.

[CSG Mike]

I can.

You really need to be talking to your engine builder to determine what is appropriate for your application.

[Turdinator]

Originally Posted by bju90

Has anyone fitted a set of the ultimate street or rally cams from Piper to an NA engine and can comment on the results they saw?

I am looking at a simple NA build for circuit racin: 8k rev limit (stock bottom end), 2017 intake manifold (limited to stock manifold by regs), EL 4-1 headers, mild port/polish to clean up the stock castings, cams, valve springs. Was thinking the SUBFA20BP300 ("Rally" cam) but unsure if this might be too aggressive.

I have been in contact with Piper but they seem very reluctant to provide any selection advice.

I know this isn't exactly what you have asked but I'll throw it out there as an FYI. Oil pressure on the standard block is known to become unreliable once you go much beyond stock redline. Also do some research on the Piper cams for our engine. There have been reports of camshaft breakages floating around.

[bju90]

Originally Posted by CSG Mike

I can.

You really need to be talking to your engine builder to determine what is appropriate for your application.

I am my engine builder.... I am still in the stages of compiling all the necessary information to make the decision on cam selection and far off finalising anything. This will be my first build (have to start somewhere). Background: Mechanical Engineer. So if you have any info you would can share it would be much appreciated. The more technical the better :P.

Originally Posted by Turdinator

I know this isn't exactly what you have asked but I'll throw it out there as an FYI. Oil pressure on the standard block is known to become unreliable once you go much beyond stock redline. Also do some research on the Piper cams for our engine. There have been reports of camshaft breakages floating around.

It seems oil pressure is an issue above 8200 RPM. I will be monitoring oil pressure and raising the limit to somewhere between 7800 - 8000 RPM. Hopefully the rods hold up.

[CSG Mike]

Originally Posted by bju90

I am my engine builder.... I am still in the stages of compiling all the necessary information to make the decision on cam selection and far off finalising anything. This will be my first build (have to start somewhere). Background: Mechanical Engineer. So if you have any info you would can share it would be much appreciated. The more technical the better :P.



It seems oil pressure is an issue above 8200 RPM. I will be monitoring oil pressure and raising the limit to somewhere between 7800 - 8000 RPM. Hopefully the rods hold up.

Flowbench your heads, figure out your flow and flow requirements, make sure you have the header and manifold to support the flow, and then pick your cam.

[bju90]

Originally Posted by CSG Mike

Flowbench your heads, figure out your flow and flow requirements, make sure you have the header and manifold to support the flow, and then pick your cam.

Well I am limited to the stock manifold so I believe this to be the limiting factor. As for head flow I have been running off FBM as target figures:

Exhaust Flow @ .500 = 220

Intake Flow @ .500 = 305

Exhaust manifold - Only limited by the imagination, Ace, SME or make my own if need be.

I am starting to think the ultimate road is the safer bet. Can sit here and do all the calculations and research in the world but until they are installed I wont know the result.

Hence why some one with real world experience would be nice to chime in but no one wants to open up including piper.

[Scrappydoo]

Originally Posted by bju90

Well I am limited to the stock manifold so I believe this to be the limiting factor. As for head flow I have been running off FBM as target figures:

Exhaust Flow @ .500 = 220

Intake Flow @ .500 = 305

Exhaust manifold - Only limited by the imagination, Ace, SME or make my own if need be.

I am starting to think the ultimate road is the safer bet. Can sit here and do all the calculations and research in the world but until they are installed I wont know the result.

Hence why some one with real world experience would be nice to chime in but no one wants to open up including piper.

It does seem frustrating even from reading this post. I suspect you are asking a question that nobody has the individual experience or knowledge to answer hence the marked reluctance to actually provide any useful information.

You may just have to suck it and see

[bju90]

Originally Posted by Scrappydoo

It does seem frustrating even from reading this post. I suspect you are asking a question that nobody has the individual experience or knowledge to answer hence the marked reluctance to actually provide any useful information.

You may just have to suck it and see

Exactly how I feel lol.

I was hoping Piper or their distributors on the board could chime in with something but evidently not. Only testing is the German guys who broke 2 sets. They appear to be largely untested I guess, even pipers response via email

"We do not have any dyno test results in house as we are a manufacturing plant, but I can request some information from previous customers supplied"

Never came back with anything in the end.

This was supposed to be a stepping stone to a larger project but looks like I will have to go further down the path of education on cam design earlier than I had hoped to meet my needs. Probably better to get something custom made locally.

[Turdinator]

Have you spoken to @Tim Radley he seems to have some experience with Piper Cams.

See this thread: http://www.ft86club.com/forums//show...t=91080&page=2

[bju90]

Good find! I think id be best with the ultimate road and hope the 2017 manifold flows better.

[twag4]

Originally Posted by Turdinator

I know this isn't exactly what you have asked but I'll throw it out there as an FYI. Oil pressure on the standard block is known to become unreliable once you go much beyond stock redline. Also do some research on the Piper cams for our engine. There have been reports of camshaft breakages floating around.

Do you have any knowledge of cam breakage besides the incidence with the German video that is listed on one if these. Threads? Not being snarky, but I have piper cams going in a built engine as we speak. I just want to read about any other issue, as I have seen this statement made before, but am only aware of that incident. I want to know if I bought the wrong brand!

[sw20kosh]

@bju90 I am using the stg3 cams in my built motor. The results were disappointing. The shape of the torque curve did not change from stock. Current theory is the intake manifold is the bottleneck.

Pm me if you want more specifics.

[go_a_way1]

Any input on one of these cams with FI??

[Kodename47]

Read this?

http://www.ft86club.com/forums/showthread.php?t=91080