C1J Cam timing

[TNT ANDY]

First of all, a big thanks to Oli and Handy for coming over last night and helping out with my cam timing. As Scoff suggested, there was probably something wrong with power dropping off too low down in the rev range.

We had a look at the cam timing last night and although really difficult to accurately guage this, it look like we're about 129 deg atdc at full lift on the inlet on number 1. I know this is quite far out, but what kind of improvements can be made and what where would you expect to gain anything?

At the moment I stop making any more power @ 5500 rpm and it starts to drop off @ 5900

Any input greatfully recieved.

[TNT ANDY]

No takers?

[Slim]

I have the same problem :disagree: not sure whyyyyy,,

[TNT ANDY]

I have the same problem :disagree: not sure whyyyyy,,

I think it may be a crap 285 profile, they are well known for being poor. I have a vernier etc, just need to get it on there and time it up.

[Slim]

I think it may be a crap 285 profile, they are well known for being poor. I have a vernier etc, just need to get it on there and time it up.

What does that mean? its faulty? lol

[Dave Reed]

I'd be fitting the vernier and timing it up correctly..

[Markey Mark (BD)]

I'd be fitting the vernier and timing it up correctly..

:agree:

[Brigsy]

I'd be fitting the vernier and timing it up correctly..

:agree:

[rs250nut]

:agree:

:agree:

[Slim]

Im pretty sure the vernier is fitted,,, and i think the timing is std. Im not the one who done it tho.. I js got the parts,, someone else fitted it..

[TNT ANDY]

The response is conclusive - the vernier goes on soon.

Thanks Chaps
:)

[Os8472]

Get the vernier on there and we'll get the timing right, you'll be surprised at the difference

[TNT ANDY]

Not being funny Ol' but it don't feel like a slouch LOL. I'll do another measure and double check. According to a significant other if we where 129 deg atdc we would see it reving more freely?

[Os8472]

Not being funny Ol' but it don't feel like a slouch LOL. I'll do another measure and double check. According to a significant other if we where 129 deg atdc we would see it reving more freely?

Interesting, I'll not pretend to know everything about cams but what I do know is I set my 285 the same as you did to start with, retimed later with Andy's help to 110 and the difference was alot

[Scoff]

Interesting, I'll not pretend to know everything about cams but what I do know is I set my 285 the same as you did to start with, retimed later with Andy's help to 110 and the difference was alot

The problem with Piper is that it's a lottery when it comes to getting one with good base timing ! Normally they do not make good power if they are overly advanced. Andy's is the other way. Maybe it's too far the other way for the normal rules to apply, who knows ? but either way if he adjusts the timing much then his map is likely to be some way out afterward. :crap:

[Os8472]

The problem with Piper is that it's a lottery when it comes to getting one with good base timing ! Normally they do not make good power if they are overly advanced. Andy's is the other way. Maybe it's too far the other way for the normal rules to apply, who knows ? but either way if he adjusts the timing much then his map is likely to be some way out afterward. :crap:

Good point, bloody cams :crap:

Another reason why I haven't gone high lift with my f7r yet

[GTphil]

When I fitted my piper 285 it was pretty much bang on at 112 degrees, mine wasn't a re-grind, maybe that's why, or maybe I just got lucky.

[TNT ANDY]

The problem with Piper is that it's a lottery when it comes to getting one with good base timing ! Normally they do not make good power if they are overly advanced. Andy's is the other way. Maybe it's too far the other way for the normal rules to apply, who knows ? but either way if he adjusts the timing much then his map is likely to be some way out afterward. :crap:

I'll be waiting until this season is out, fit the vernier then over to you again Scoff, I just don't have the time to get over to you b4 Blyton prk. But I still like it as it is, this is more fine tuning I feel.

[Andrew Cooke]

When I fitted my piper 285 it was pretty much bang on at 112 degrees, mine wasn't a re-grind, maybe that's why, or maybe I just got lucky.

you were lucky:agree:

[Fordy]

my regrind 285 on a stock timing gear was 132degrees !

so glad I brought a vernier..timed to 109degrees and its made my turbo technics t25 a whole new animal to drive

[TNT ANDY]

Ok - you've talked me into it, I'll plan to get it done ASAP.