Cam timing changes
#16
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Originally Posted by cambria
Is the reccomendation to set the PS to 7 degrees and the drivers side to 8 degrees?
The 7/8 was cool around town, but on the dyno it took about 20HP off the table on my '86.
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Originally Posted by cambria
Is the reccomendation to set the PS to 7 degrees and the drivers side to 8 degrees?
I'm going back in there shortly for a new t.belt and Ken's new tensioner project and may consider adjusting again if I can get sufficient seat time with the present set up - it's friggin snowing again.
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Originally Posted by PorKen
...... Malcom is using 6° (8° hole on the V1 tool) which I think is the max which doesn't take away too much HP on top.....
Glenn
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Originally Posted by PorKen
I was on the dyno, yesterday. (Clone chips, X-pipe, RMB, PKsn'r.) At 8° I managed 304rwtq, at around 4000rpm, but IIRC, HP was only ~274@5500! But, at 0°, it was very close at 297, but at 4500rpm, and rwhp was 297@5800. (no TB covers).
Glenn
#20
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Glenn,
Advancing will probably raise NOx, as the dynamic compression ratio is raised.
0° with engine warm, both sides. On the V1 tool, that would be usually be one hole CCW. When cold, it would be 0°L/-1°R.
Louie reckons I might be able to get over 300RWHP with a little retard, as the HP is almost flat from 5500-6200, with a slight drop after 6000.
Advancing will probably raise NOx, as the dynamic compression ratio is raised.
0° with engine warm, both sides. On the V1 tool, that would be usually be one hole CCW. When cold, it would be 0°L/-1°R.
Louie reckons I might be able to get over 300RWHP with a little retard, as the HP is almost flat from 5500-6200, with a slight drop after 6000.
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Ken,
Gotcha. Am I right in concluding then that all previous talk of using 8 degrees advance would mainly be of advantage to those with an auto box then? With a 5- spd, maybe I should just stick to the stock 2L/1R timing as near optimum? Thoughts or opinions?
Glenn
Gotcha. Am I right in concluding then that all previous talk of using 8 degrees advance would mainly be of advantage to those with an auto box then? With a 5- spd, maybe I should just stick to the stock 2L/1R timing as near optimum? Thoughts or opinions?
Glenn
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Originally Posted by sharkmeister85
Ken,
Gotcha. Am I right in concluding then that all previous talk of using 8 degrees advance would mainly be of advantage to those with an auto box then? With a 5- spd, maybe I should just stick to the stock 2L/1R timing as near optimum? Thoughts or opinions?
Glenn
Gotcha. Am I right in concluding then that all previous talk of using 8 degrees advance would mainly be of advantage to those with an auto box then? With a 5- spd, maybe I should just stick to the stock 2L/1R timing as near optimum? Thoughts or opinions?
Glenn
My question is, as the rotor is bolted to the cam hub how is the ignition timing change affecting the performance? Advanced cam and ignition appear to be good results...........long term effects?
#23
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It depends how you drive, I reckon. I'm such a died-in-the-wool auto driver that driving a GT makes me uncomfortable, rev'ving up to 4000rpm to shift seems so foreign. If you do most of your driving in the city, and/or you want to have more grunt off the line, without having to dump the clutch, then some advance wouldn't hurt.
The ignition trigger is taken from the crank, so it doesn't change. The ignition rotor has a broad tip to match the range of the adjustable cam gears.
The ignition trigger is taken from the crank, so it doesn't change. The ignition rotor has a broad tip to match the range of the adjustable cam gears.