Brian Crower 7M cams and ignition timing issue

[amichie]

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Hey

I have just fitted a set of brian crower stage 2 cams to my 7MGE and now I cant get enough static ignition advance before I hit the end of the adjustment range. Max advance at idle I can get is about 5 deg BTDC.

I have tried popping the dizzy out and advancing it by one tooth on the drive gear but this gave way too much advance.

Anybody else tried these cams out and had similar issues??

I may just file out the slot to get about another 10 degrees advance.

Factory setting is 10 deg BTDC and I have found it runs well with upto 15 deg BTDC on premium gas.

 

[IJ.]

Interesting sounds like someone got the phasing on the Helical gear a little off during production.

Would like to hear from anyone else using these cams to see if this is just an isolated case.

If needs be you can pull the CPS apart and rephase the Reluctors to suit getting your full range of adjustment back again.

 

[AJ'S 88NA]

Interesting sounds like someone got the phasing on the Helical gear a little off during production.

Would like to hear from anyone else using these cams to see if this is just an isolated case.

If needs be you can pull the CPS apart and rephase the Reluctors to suit getting your full range of adjustment back again.

No CPS on a NA. Check your timing gears at marks, #1 at TDC, rotor pointing at # 1 on the distributor, and the crank mark at "o". Sounds like something is still out.
Make sure you adjust the timing belt right according to the TSRM.

 

[IJ.]

AJ: It can still be rephased as the reluctors are just pressed onto the shaft the same as the CPS (I used to trigger a standalone using a modded NA Distributor)

 

[amichie]

No CPS on a NA. Check your timing gears at marks, #1 at TDC, rotor pointing at # 1 on the distributor, and the crank mark at "o". Sounds like something is still out.
Make sure you adjust the timing belt right according to the TSRM.

Done this and double checked a few times now.

I also think the drive gear is out of phase.

I think of all these cams that have been sold nearly all are still sitting in boxes and have not been tried.

 

[AJ'S 88NA]

AJ: It can still be rephased as the reluctors are just pressed onto the shaft the same as the CPS (I used to trigger a standalone using a modded NA Distributor)

O.K. I thought I had read that somewere, just that he didn't say he had done that.

 

[AJ'S 88NA]

Done this and double checked a few times now.

I also think the drive gear is out of phase.

I think of all these cams that have been sold nearly all are still sitting in boxes and have not been tried.

It seems that if the drive gear was off it would have a hard time turning without causing some damage?
I see alot of questions asked about these cams, but few responses? Maybe alot of them are still sitting in their boxes.

Am I missing something? This thread was moved from the General section, to the GTE section and he says it's a GE?

 

[amichie]

It seems that if the drive gear was off it would have a hard time turning without causing some damage?
I see alot of questions asked about these cams, but few responses? Maybe alot of them are still sitting in their boxes.

Am I missing something? This thread was moved from the General section, to the GTE section and he says it's a GE?

Yes it was moved by the moderator and yes it is a GE (non turbo)

Here is an update.

I filed out the slot a little and now I have enough static advance for general driving.

Idle is crap and it regularly stalls. I might have to tweak the cam timing a little as there must be too much overlap for steady idle.

I'm guessing that advancing the exhaust cam slightly might be the way to go since that will improve both the static ignition advance and reduce the overlap slightly.

Having fun anyway.

 

[IJ.]

AJ: Phasing as in where a tooth on the Cam is in relation to the middle hole on the front of the Cam.

Move that a few degrees and you run out of travel in the Distributor/CPS adjustment slot before you get the correct ignition timing.

 

[amichie]

AJ: Phasing as in where a tooth on the Cam is in relation to the middle hole on the front of the Cam.

Move that a few degrees and you run out of travel in the Distributor/CPS adjustment slot before you get the correct ignition timing.

100% agreed.

Can I ask where in Aus you are roughly??

 

[IJ.]

I'm in Melbourne

 

[AJ'S 88NA]

Yes it was moved by the moderator and yes it is a GE (non turbo)

Here is an update.

I filed out the slot a little and now I have enough static advance for general driving.

Idle is crap and it regularly stalls. I might have to tweak the cam timing a little as there must be too much overlap for steady idle.

I'm guessing that advancing the exhaust cam slightly might be the way to go since that will improve both the static ignition advance and reduce the overlap slightly.

Having fun anyway.

I take it you have adj. cam gears? Do you have any type of AFR adjustment? Just curious if you can get it running well enought without some sort of piggyback(i.e. Apexi, etc.) When I installed my cams it was with other mods, bored, stroked, etc., and I had to install a Apexi II to get it to run decient. It would run OK, just wouldn't run GOOD. I also had problems with idle.

I still don't understand why the thread was moved from Gen Diss., to GTE when you have a GE? Are you going GE-T.

Also thanks for the lesson IJ.

 

[amichie]

I take it you have adj. cam gears? Do you have any type of AFR adjustment? Just curious if you can get it running well enought without some sort of piggyback(i.e. Apexi, etc.) When I installed my cams it was with other mods, bored, stroked, etc., and I had to install a Apexi II to get it to run decient. It would run OK, just wouldn't run GOOD. I also had problems with idle.

I still don't understand why the thread was moved from Gen Diss., to GTE when you have a GE? Are you going GE-T.

Also thanks for the lesson IJ.

I don't know why it was moved by the moderator and I have no plans to go turbo. The moderator did send me a very polite PM saying it was being moved and I'm not that fussed about it.

Oh and I have only one 5 bolt adjustable cam gear and one factory vernier gear. I think I will try reduced overlap with my 5 bolt gear on the intake cam and if that improves idle then I will remove the exhaust cam gear and advance it by 6 crank degrees.

 

[IJ.]

AJ: Very welcome I learned all about it when I made my own billet cam for my old 3.4L Toyota V8 way back when

No idea why Duane moved it but it's back where it's meant to be now

 

[AJ'S 88NA]

AJ: Very welcome I learned all about it when I made my own billet cam for my old 3.4L Toyota V8 way back when

No idea why Duane moved it but it's back where it's meant to be now

Is there anything you haven't made?:biglaugh: Except "baby buggy rubber bumpers"

Amichie: Interested to see if you can get it to run well enough without fuel control and just timing. Please keep us posted.

 

[IJ.]

AJ: Been doing this a very long time and in the old days we made just about everything as there was very little "aftermarket" available

 

[amichie]

Is there anything you haven't made?:biglaugh: Except "baby buggy rubber bumpers"

Amichie: Interested to see if you can get it to run well enough without fuel control and just timing. Please keep us posted.

It seems to me that degreeing of the cams is required.

The fact that the ignition timing was retarded so much and that the idle is so bad suggests to me that there is a lot of static retard on the exhaust cam.

I assumed the dowel pin holes would be set up so that if you use the middle pin hole on both the cam and the wheel then the timing wold start off in a neutral position. I will try and do some kind of check on valve opening and closing angles to try and figure out if the cams are biased one way or the other.

 

[IJ.]

Degree them per the timing tag so you have a baseline 0 point then go from there (sorry didn't realise you hadn't degreed yet)

 

[amichie]

Degree them per the timing tag so you have a baseline 0 point then go from there (sorry didn't realise you hadn't degreed yet)

Why the XXXX wouldn't they do it from the factory. If toyota can do it then Brian Crower should be able to.

They did supply a little timing card. A few pics below

 

[IJ.]

There are a bunch of variables that will affect the Cam's true 0 point such as ANY machine work done on the block or head, Belt stretch, Pully wear, Head Gasket thickness and so on.

This is why they give you the "220@50 thou" Spec so you can degree them in and when your degree wheel says 220@50 thou you look at the Cam pully and this will be YOUR motor's true 0.

From memory 1mm difference is around 2>3 degrees.