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Discussion Starter #1
Hi all

with an upgraded v6 ( turbo etc ) whats the best Timing Degree if any have been tested. Or should it just be set to Zero TDC

thx
 

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Are you using verier pulleys .. if not then as far as i can see on these engines cam timing is a real nightmare. guess the only way forward is time spent on a rolling road. but having to mark the standard pulleys up fitting cam locks adjusting the pulleys on the cam tightening everything up and then re testing would get very expensive for what might be small gains.. are you using standard cams or a set designed for the turbos..

At a guess setting the cams with as little overlap as possible is usually a good step on turbo engines
 

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Discussion Starter #3
Thx for reply Maxi

Ive lazy so ive not completed the adjustable pulleys but i will get them finished and put them on , as i have all the parts made i just need to do a little drilling and cutting to finish them off.

I need to pull the engine out yet again to fit a better gearbox with LSD , but its been to cold for me :biglaugh:

So ive bought a space heater and going to have a fiddle this week.

Ive been pondering over new cams but how am i going to get round not being able to use cam locks.

Can i mark the cams and head with locks on before i send them off for re-profile and when they are back line the marks up. or is it going to be completely different timing set up.
Other then that i guess i could go GTA cams but not much gain for the same cost as a re-profile.

So if you and anyone can help me with how to go about with timing with re-profiled cams please help then i would be more excited about doing it :biglaugh:
But what ever happens i need to get this car finished this year :depressed:

Thx in advance
 

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If the cams are reprofiled then they will have the timing info with them. Your right you wont be able to use the cam locks, you will need to use a timing disc on the crank with it rotated to whatever degrees btdc the cam info gives you and then adjust your vernier cam gear to max lift on number 1 for both inlets and exhaust cams measured with a dti gauge.

Its been a long time since I built an enging with reprofiled lift and duration cams, It was a ford pinto but it will e the same principal.
 

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Thx for reply Maxi

Ive lazy so ive not completed the adjustable pulleys but i will get them finished and put them on , as i have all the parts made i just need to do a little drilling and cutting to finish them off.

I need to pull the engine out yet again to fit a better gearbox with LSD , but its been to cold for me :biglaugh:

So ive bought a space heater and going to have a fiddle this week.

Ive been pondering over new cams but how am i going to get round not being able to use cam locks.

Can i mark the cams and head with locks on before i send them off for re-profile and when they are back line the marks up. or is it going to be completely different timing set up.
Other then that i guess i could go GTA cams but not much gain for the same cost as a re-profile.

So if you and anyone can help me with how to go about with timing with re-profiled cams please help then i would be more excited about doing it :biglaugh:
But what ever happens i need to get this car finished this year :depressed:

Thx in advance
yeah little difficult as you have no keyways but would have to fit the pulleys locked up and set everything up with a dial gauge to the cam re-profilers setting using a dti gauge. i,m going to do the same and once set up make a set of cam locks so its easy from then on... lol
 

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This info may or may nor be useful ... but .... I built a 3.8 litre Busso using an AHM kit that included AHM designed "fast road" cams. The timing of these cams must be done with a DTI and the method is to ascertain the exact point maximum lift is achieved using a DTI on the cam follower. Before doing this you establish TDC on # 1 cylinder with a degree disc on crank pully and then turn the engine forward so crank is 110 deg after TDC, you then set that position for the exhaust cam. In other words the exhaust cam is at maximum lift 110 degrees ATDC. The same system is used for the inlet but at 110 deg before TDC. That's # 1 the first cylinder on the left hand side. Pretty sure that the right hand bank ( viewed from front ) its # 5 cylinder you need to set to the same timing but with the engine rotated 180 degrees. In other words # 1 & # 5 are at TDC together but one is on power stroke and the other is on exhaust.
I used Vernier pullies but the std pullies can be used if you are canny. Be aware that I used home made cam locking tools but if you buy 4 round jawed "mole" vice grips from a pound shop and use these to hold each cam in place once they are in desired place. Not sure this will help but .................... there you go,
 

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First question: Did it work? What is the bhp on your current setting? :paperbag:
Yes, it works great. These are fast road cams ( not too 'cammy' with not too much overlap ) and are ideal for my application which includes a Rotrex supercharger. The BHP is 345 BHP at the wheels. The torque in 4th gear on the motorway from 4000 RPM > 7300 is sensational hence me saying these cams and their timing settings are ideal.
 

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Discussion Starter #9
Thanks alot AlfaMail

That is a great help i just need to decide which profile to go for , it may be just fast road piper cam set up. ive got time to think it may even be a case of pick from a hat :biglaugh:

:thumbup:
 

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Thanks alot AlfaMail

That is a great help i just need to decide which profile to go for , it may be just fast road piper cam set up. ive got time to think it may even be a case of pick from a hat :biglaugh:

:thumbup:
contact Jim K or catcams and tell them a spec and get a custom profile made ... higher lift cams dont always work better with turbo cars as they normally increase the duration.
you need reduced duration to make better benefits on turbo cars iirc
 
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