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Can you tell me what is normal with Tomei 256cams? people are saying they idle like stock but looking at 4 utube video's they idle the same as mine, and thats a long way from stock. The tuner showed me as he adjusted fuel mixtures from over 15.3:1 down to 14.5:1

tried different cells making them richer/leaner, so is this really about the tune or the Cams??????

can my cam timing be changed as in retard/advanced to help smooth this idle and low speed jolting?

This comment "fuel mixtures from over 15.3:1 down to 14.5:1" throws up issues from the get go with cams, it should idle nearly std if its tuned right.

DO you have a hand controller? ive got a quick test you can try.

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Hey Mark,

Heard my car running on a video for the first time yesterday and it has 260 poncams with 9.15 lift, it is smooth az during low revs and at idle.... Even though its untuned.... Just a bit of feedback :yes:

That just makes this even more frustrating then, im sure i can remember mine idling perfect the very first time starting it, was even bit disappointed cause it was so smooth,

then the cas broke, so i replaced that then the 555's then a Z32 and tune, and now i have this.. :unsure:

Not really if its getting done properly and by $650 im assuming full retune, here's my thoughts on tune touch ups and why we dont do them.

We dont touch up other shops tunes full stop, a tune from us would be the same price $650. First thing we do is revert to default and work from scratch on EVERY car, we do this for two reasons ONE is to make sure each parameter is the way "I" like it and the SECOND reason is we dont want to take on the possible faults from the other tune which may cause it to come back (things like cold start etc).

That $650 is not just a tune charge but a goodwill charge which means we take on FULL responsibility for said tune... any cold start issues etc we will cover and not recharge to remedy if need be (rare but possible). Any engine mods done down the track get charged @ 150 P/hour,we can do this as we have a known good base to work from (most mods only take an hour or two at the most to tune for).

Theoretically if i was to "touch up a tune" and charge $150 to fix a idle issue many people then assume i have fixed the tune, this is not so.... what if these changes at operating temp make the car hard to start cold or hot or introduces a stumble... the customer comes back and complains and then i have to patch another part of the other tune... and so and so on it often snowballs as the underlying base is not right.... and the responsibility for the tune in the customers eyes falls on me even though ive only done the idle and relevant parts..

:worship:

Very well explained and a good price for the touch up tune (after you have done the full tune)

Thanks for clearing that part up.

I had the same issue when I was going to get a basic tune that would allow me to limp to Jez's

then get Jez to touch it up but that wasnt very cost effective.

If someone changed a turbo is that charged at $150p/hour or because its a huge change then it will cost more?

taking the car back friday, rang tuner this morning, he is thinking it maybe running a bit lean on light throttle and there could be a vacumn leak somwhere, but ive gone thru that over and over,

what things can i check on this power fc for idling?? the following i can see on controller

Injectors 62.5% 0.18ms

Throttle 0,37V at 950revs

A/F meter 1.28V

02-1 is 0.02

the $650 was the quote off a different tuner that i was asking so i could have a second opinion, but obviously dont want to spend that.

i am going back to same tuner this friday to see if he can explain whats doing with it.

i made short vid if it helps, it doesnt sound that bad but does get worse after driving and this doesnt show the jolting it does.

http://youtu.be/lZcehjuxYbg

Edited by SliverS2

Not really if its getting done properly and by $650 im assuming full retune, here's my thoughts on tune touch ups and why we dont do them.

We dont touch up other shops tunes full stop, a tune from us would be the same price $650. First thing we do is revert to default and work from scratch on EVERY car, we do this for two reasons ONE is to make sure each parameter is the way "I" like it and the SECOND reason is we dont want to take on the possible faults from the other tune which may cause it to come back (things like cold start etc).

That $650 is not just a tune charge but a goodwill charge which means we take on FULL responsibility for said tune... any cold start issues etc we will cover and not recharge to remedy if need be (rare but possible). Any engine mods done down the track get charged @ 150 P/hour,we can do this as we have a known good base to work from (most mods only take an hour or two at the most to tune for).

Theoretically if i was to "touch up a tune" and charge $150 to fix a idle issue many people then assume i have fixed the tune, this is not so.... what if these changes at operating temp make the car hard to start cold or hot or introduces a stumble... the customer comes back and complains and then i have to patch another part of the other tune... and so and so on it often snowballs as the underlying base is not right.... and the responsibility for the tune in the customers eyes falls on me even though ive only done the idle and relevant parts..

This times 11tybillion. Have recently learnt this

well thats all fair enough

My problem seems to occur hot or cold, i drove the car this morning and ive noticed that this is a very light throttle problem

the jerking happens between 1000rpm and 2000rpm with upto 10%throttle, even at 3000rpm on this throttle position it wants to jerk but you can just feel and hear it hesitating slightly.

I dont think it is the cams or a vacumn leak or the intake pipe, it has to be tune or timing , although at about 5psi i can hear a leak of some sort like a horn blowing or a cat noise under bonnet still. I tightened up exhaust bolts and still there.

Hypothetically speaking would a stretched timing belt cause the exhaust cam to be out enough to do this?

anyone have any suggestions here? what could be causing this?

Edited by SliverS2

no havnt changed the intake pipe, if it were a air leak it wouldnt hold its idle so well would it?

its more like full on missing,

what if i could connect the airflow directly to the cross over pipe? would that eliminate a vacumn leak?

Get wd40 and spray it around the injector seals and where the plenum meets the head while engine is running. See if anything changes.

I have to replace intake gaskets on a rb26 tonight due to a constant miss at idle, un noticable at higher rpm.

I diagnosed it as cylinder 2 plenum gasket leaking. U should see the thing plume smoke out of the gasket when i have the smoke tester on it.

no havnt changed the intake pipe, if it were a air leak it wouldnt hold its idle so well would it?

its more like full on missing,

what if i could connect the airflow directly to the cross over pipe? would that eliminate a vacumn leak?

Also what ecu do u have? If its a power fc be sure u havent selected the wrong afm by accident

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