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Timing, pulley wheel and cam shaft query???
Avoneer - 27/9/04 at 07:07 PM

Hi Guys,
Before I have a heart attack pricing up a new cam kit and vernier pulley, someone please tell me if I really need one????

I currently have a 2ltr Pinto with an unknown/un-identifiable AE cam, twin 45's, normal pulley wheel and standard dizzy and small black ignition amplifier module.
Will a rolling road be able to set all this up to the best of their ability without knowing what the cam is or do I need to start spending some money.
As I plan to sell my tiger early next year, would prefer the first option, but just wondering if a rolling road session would be cost effective or just a waste of time?
May be I could get away with just a new standard cam???
Cheers,
Pat.....


Viper - 27/9/04 at 07:20 PM

stick it on the rollers, simple.
Tim


Avoneer - 27/9/04 at 07:57 PM

Hi Tim,
Will they be able to tweek and twiddle and make it half decent just with what i've got though????
Pat....


dblissett - 27/9/04 at 08:37 PM

stick it on the rollers and they will sort it out
you only need adjustable pulleys if you are trying to get the last drop of power out of the set up
ps if its all standard the twin 45s are a bit over kill
so check what the chokes are
good luck dave


Rob Lane - 27/9/04 at 10:23 PM

If it's a non standard grind cam then the standard pulley wheel will definitely not be spot on.

Without a rolling road it is possible to ascertain whether cam timing is set properly. Although to be honest I've not done a Pinto.

If it's a regrind the same applies, as when the profile is reground the operative has to take account of pattern and lobe. This means that there is an offset from optimum.

A vernier pulley will give you the ability to time a cam spot on.

To say that a roller tuner will set it up spot on is nonsense without a vernier. The standard cam wheel is non adjustable and the above applies.

Just being 3-5 degrees out can make a great deal of difference to the car, depending on state of tune it could be as much as 10% power loss.

[Edited on 27/9/04 by Rob Lane]


Rob Lane - 27/9/04 at 10:45 PM

I've posted three jpegs of a cam timing article by Dave Walker of CCC fame.

They are probably quite large and really need downloading and zoom once to read.

They are in photos album of Rob Lane.

If you want I can email the pics.

I used to time cams on Xflows with the crankshaft timing wheel and dial guage.
After reading the article I used dual dial guages and got spot on timing. Improved engine tuning as a result.

[Edited on 27/9/04 by Rob Lane]


Avoneer - 28/9/04 at 11:39 AM

I can live with a 10% power loss though rather than spend £60 on a vernier - and besides, will they still be able to set up the vernier without knowing the cam details?
Pat.....


Rob Lane - 28/9/04 at 12:49 PM

10bhp loss from 100bhp, that will feel significantly different when retuned.

At around £20 per bhp rough tuning costs on engines that's quite a saving.

i.e. adding twin webers at say £400, manifold say £150 and all to gain 15bhp without other mods.

You can time the cam without knowing it's details, as per article I've posted.
I've used this method on many a crossflow and it works everytime.

Measure it first and don't buy a vernier unless the timing is way out.

[Edited on 28/9/04 by Rob Lane]


Viper - 28/9/04 at 04:37 PM

whoever does your rolling road will set up the carbs and ignition to its optimum, but won't set your cam timing, have you any numbers stamped on the very back of the cam? who supplied the cam?
Tim


Avoneer - 28/9/04 at 05:03 PM

Hi Vipe,
The cam has AE and F96 & 5723 on the end and GC 0916 & K355-C on the shaft.
I have emailed AE a number of times, but have had no responce.
Cheers Rob, will have a good luck at the pics and article and take it from there.
Pat....

[Edited on 28/9/04 by Avoneer]


Viper - 28/9/04 at 05:52 PM

I didn't know AE made performance cams, only stock replacements, course i could be wrong just never heard of it..


Avoneer - 28/9/04 at 06:12 PM

That may bethe answer then Viper - a stock cam?????
I'm still happy with how fast it goes at the moment though!
Pat....


Viper - 28/9/04 at 06:15 PM

i would still stick it on th rollers, i can guarantee your carbs are out, probably on the rich side


Avoneer - 28/9/04 at 06:22 PM

Cheers.
Will get Elvington out of the way first and then worry about it after that. Need a new exhaust anyway as the Tiger one is now almost hollow and the headers were never perfectly flat against the head anyway...
Can't wait to commence on the Fury, that should be a piece of wee after the Avon.....
Pat.....


Northy - 28/9/04 at 08:03 PM

quote:
Originally posted by Avoneer
Need a new exhaust anyway as the Tiger one is now almost hollow....


SNAP! But mines sat on the garage floor! Never fitted it. Its a better bell than exhaust!


Viper - 28/9/04 at 08:06 PM

Standard Tiger quality then...
(can the words Tiger and quality be used in the same sentence?)


Northy - 28/9/04 at 08:09 PM

quote:
Originally posted by Viper
Tiger quality


Shuder!


Jon Ison - 28/9/04 at 08:20 PM

IMHO you can set the cam up "perfect" as per book with dial gauge ect but on the rollers you can swing it looking for that last little bit, no two engines are the same and only the rollers can give the true story, same with carbs, you can't get the optimum out of a book, summat near yes, optimum no.


Avoneer - 29/9/04 at 09:46 PM

So, would I be right in saying that if you have a standard cam and standard pulley wheel, the pulley can only go on in one place and therefore cam timing is irellevant?
Therefore, if I use my standard pulley with my cam which may or may not be a fast road one, then I will (may) only loose a percentage of power due to not being able to "fine tune" the cam.
Does that make sense???~
Pat....


Rob Lane - 29/9/04 at 09:58 PM

Makes sense and yes correct.

If the cam has been reground at all, then it may have been reground off from ideal timing.
However, if it's standard then it should be close to optimum.

Despite what has been said, unless you ask specifically for it to be done, a rolling road will only attempt to set up fuel and ignition.


Avoneer - 29/9/04 at 10:15 PM

So considering my set up and unwillingness to spend any more money, I'd be best leaving the cam alone and just worrying about the timing and carbs on the rolling road and just let the cam do what it's going to do.
Cheers for all the info - when I build my Fury next year with a K series - I can worry about it all again then!
Pat.....


Northy - 29/9/04 at 11:02 PM

Fury? K series? WTF? I thought you were gonna build a Robin Hood!

You change your mind more than I change my underpants!

See you Saturday.

Cheers