How to set TDC with an aftermarket flywheel...

Author Topic: How to set TDC with an aftermarket flywheel...  (Read 7008 times)

JiXer

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How to set TDC with an aftermarket flywheel...
« Reply #15 on: June 26, 2007, 11:08:32 AM »
Quote from: romkasponka;28543
Sorry for my mistake, you should retard intake camshaft for better top end. The valve shoud be opened later and closed later. My first atempt was to advance intake, after that I got terible noise and weak top end. After I retarded intake camshaft at max posible position. And after this I lost low end torq, but top end was much better. Limiter is 7200rpm.

You can try to simulate it on the DynoSim 2003.




You have it backwards.

J.

badboypolar

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How to set TDC with an aftermarket flywheel...
« Reply #16 on: June 27, 2007, 10:34:25 AM »
This is what I do to get TDC.

After installing your flywheel and clutch set it as close to TDC as you can. Then remove the timing chain and set the cams to TDC. The flat ends of the cam should be straight across. Then set the crank to TDC (I use the long screw driver in the spark plug hole trick). Then install the timing chain.

It's worked for me everytime.

gearheadE30

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How to set TDC with an aftermarket flywheel...
« Reply #17 on: June 27, 2007, 03:21:39 PM »
Cam should be advanced, not retarded, according to everything I've heard. Anyone know for sure which? Advanced makes the most sense to me.

1991 318is Turbo
1989 Caprice Classic Wagon named Humphrey
1979 Suzuki GS750E

romkasponka

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How to set TDC with an aftermarket flywheel...
« Reply #18 on: June 27, 2007, 05:36:11 PM »
Quote from: gearheadE30;28648
Cam should be advanced, not retarded, according to everything I've heard. Anyone know for sure which? Advanced makes the most sense to me.


Why do think so? I'm saying you how I did that and what results were after adjustment. Do what you want... ;)


This setup was shit and inverted is wich I'm driving now.
E30 318is M42
E36 318is M44

badboypolar

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How to set TDC with an aftermarket flywheel...
« Reply #19 on: June 28, 2007, 03:01:13 PM »
That is a full 10 degrees advanced, you should only be 5 to 6. Advancing helps top end HP and hurt low end torque, which if you drive down low (around town) would feel worse.

Retarding helps torque. So when you drive around town it will feel alot better. But if you are racing (not necessarily atuo-x) then you would want it advanced.

Secondly you need to replace your cam sprockets. They are beat. I'd recommend replacing your chain also.

romkasponka

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How to set TDC with an aftermarket flywheel...
« Reply #20 on: June 29, 2007, 06:02:36 AM »
Quote
Advancing helps top end HP and hurt low end torque, which if you drive down low (around town) would feel worse.


You are totaly wrong. Try some simulation software.




Quote
Retarding helps torque. So when you drive around town it will feel alot better. But if you are racing (not necessarily atuo-x) then you would want it advanced.


Wrong, all is vice versa...

Quote
Secondly you need to replace your cam sprockets. They are beat. I'd recommend replacing your chain also.


Sprockets was inspected during engine rebuild. They are good enough to be used. As I said before in one thread it coud be that diferent manufacturers use diferent tooth profile, or diferent tooth profile height. Worn places are always fully polished and places which are worn litlle bit still have mashining patern.
E30 318is M42
E36 318is M44

badboypolar

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How to set TDC with an aftermarket flywheel...
« Reply #21 on: June 29, 2007, 12:55:09 PM »
I will respectfully disagree.

However I feel obligated to tell you that your cam gears are done. They should not be sharp like that (should have a flat top roughly 1.5mm long) and they should not have those deep grooves and pits in them.

Now I have to say that while I am also a stubborn and prideful person, when numerous people who have lots of PERSONAL experience with something tell me something that may be contrary to what I know, I will certainly look it up. Before I started doing things myself I had many mechanics who told me something that was totally wrong. They didn't know any better at that time.

I've tuned many cars and advancing the timing in conjunction with added fuel is one of the easiest ways to get some HP up top. When you retard the ignition it helps down low. This is of course all to a point. At a certain point you start to lose horsepower or torque when you go beyond that peak.

If you are beyond the point especially with timing you can lose power really fast. Two years ago I was tuning a Honda and this guy wanted to use a certain chip, it had timing advanced way too far. I had to convince him that the timing up top need to be retarded back to a certain point. The timing was still advanced but not to that point that the chip values started at. But it was a gain of 8 horsepower for 7 degrees (35 degrees vs. 42) in one small change. That combined with 3 degrees advanced intake and 2 degrees retard exhaust, combined with fuel mapping, and it came out to 12 hp gain for that tune, the engine as a whole gained 60hp. I built and tuned that motor.

I hope you don’t take this as a personal attack, yet as a learning experience. It’s hard a prideful person to accept that you are wrong, believe me I know (ask my wife). However if you continue to “know” you are correct, in the face of data that suggest otherwise, you’ll end up with a ½ ton paperweight.

romkasponka

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How to set TDC with an aftermarket flywheel...
« Reply #22 on: June 30, 2007, 02:48:55 AM »
best is 7 degress retarded setup, exaust stock.
E30 318is M42
E36 318is M44

romkasponka

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How to set TDC with an aftermarket flywheel...
« Reply #23 on: June 30, 2007, 03:02:35 AM »
check Catcams.com
E30 318is M42
E36 318is M44