Cam Gear Timing Adjusting

[goldeninja20]

Im a little confused on the direction in which I am retarding or advancing the cam gear. My goal was to retard the intake cam(turning counter clockwise) and advance the exhaust cam (turning clockwise). Is this correct? Remember its a 420a. If this was correct I started to knock, and boost increase from 10psi to 12psi.

 

[goldeninja20]

Bump come on someone needs to know. I want my power band a little higher without increasing knock or compression.

 

[bryanwheat]

You need a degree wheel and dial bore indicator to correctly set the cam gears.

 

[goldeninja20]

The car is perfectly timed at 0 degrees on the cams. We wanted to optimize the power band and raise it a little bit.

 

[ed1380]

So the cams have been degreed? What are the can gears set to now?

 

[bryanwheat]

So the cams have been degreed? What are the can gears set to now?

I don't think he means degree'd, i think he is saying that the gear is zero'd out.

 

[goldeninja20]

I don't think he means degree'd, i think he is saying that the gear is zero'd out.

They were zerod out, everything was fine, I just wanted to raise the power band a little. I have the exhaust advanced 2 degree and the intake still set to zero. It helped a little but i feel like it is not building boost fast at all.

 

[turboglenn]

If the engine spins the gears clockwise (viewing from the angle you see them from in the pic) the you are correct on the timing adjustment... retarding them would be to loosen the bolts and sping the center (cam) counterclockwise from the outer edge (black part)

One of the best adjustments i've found (on the 4g63 anyway) is to advance the exhaust and retard the intake (decreasing overlap) turbo cars hate overlap except for very low RPM and cruiseand overlap only helps on the initial spool... removing the overlap lets the cylinders fill better because it shuts off the exhaust and i'ts back pressure from the cylinder before the intake valve opens letting just the boost fill the empty cylinder all on it's own (well along with the piston sucking down)

This was the first adjustment of all the different methods i've tried that i was able to sit there and say i really felt a good power gain..I would imagine on a turbo's n/a motor with n/a cams you would really benefit from doing them in this manner as the NA cams have a lot moreover lap than even a factory turbo cam

 

[goldeninja20]

If the engine spins the gears clockwise (viewing from the angle you see them from in the pic) the you are correct on the timing adjustment... retarding them would be to loosen the bolts and sping the center (cam) counterclockwise from the outer edge (black part)

One of the best adjustments i've found (on the 4g63 anyway) is to advance the exhaust and retard the intake (decreasing overlap) turbo cars hate overlap except for very low RPM and cruiseand overlap only helps on the initial spool... removing the overlap lets the cylinders fill better because it shuts off the exhaust and i'ts back pressure from the cylinder before the intake valve opens letting just the boost fill the empty cylinder all on it's own (well along with the piston sucking down)

This was the first adjustment of all the different methods i've tried that i was able to sit there and say i really felt a good power gain..I would imagine on a turbo's n/a motor with n/a cams you would really benefit from doing them in this manner as the NA cams have a lot moreover lap than even a factory turbo cam

The overlap on the cams are 26 degrees (turbo grind cams). This is a high compression build. Do you think my overlap is way too high for a high compression turbo build. What do you recommend i do now you know what my 420a has. I have the exhaust advanced 3 degrees now and it feels like the car wants to rev crazy high (my power band is high). I like it, but in 5th gear, i had it floored for for atleast 15 seconds and only built 2 psi of boost. Before i would increase to full boost. What do you guys think?

 

[turboglenn]

The overlap on the cams are 26 degrees (turbo grind cams). This is a high compression build. Do you think my overlap is way too high for a high compression turbo build. What do you recommend i do now you know what my 420a has. I have the exhaust advanced 3 degrees now and it feels like the car wants to rev crazy high (my power band is high). I like it, but in 5th gear, i had it floored for for atleast 15 seconds and only built 2 psi of boost. Before i would increase to full boost. What do you guys think?

Well, top end is what you wanted, the more you go advanced with the exh cam and retarding the intake cam the more top end you'll get, I know how the spool gets, i typically run +exh and -4 intake, my thughts on the 15 seconds of spool is this .... DOWNSHIFT@!

Really, it is raising the RPM at which you will start to spool, but when you are rowing the gears of a manualthat shouldn't matter to you and once you get over comparing the "old cam timing" to the new timing's behaviour and learn to drive the new timing properly, it won't take long before you're not even noticing the spool andyou'll naturally start to keep the car in it's rev range and using a higher RPM band for your daily driving and yo0u won't even miss what it was like before.. believe me i had to do the same thing, and even though my 67mm turbo could have used the cams timedfor spool, it would depress me with the lack of top end because it would fall off so early comparedto what I was use to with the +4/-4 setuip and i still went back to the top end favoring timing