School me on cam timin'!
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- 240sx Wannabe
- Posts: 118
- Joined: Sat Aug 17, 2013 10:38 am
School me on cam timin'!
So I am fighting some issues. I just swapped my bc stage 2's for a set of JWT s1's hoping they extra lift and duration would help out. This killed my spool, it was around 3800 to full boost and now its 44-4500. So now i'm running with a much shorter powerband. On top of that recent dyno's show power dropping off after 6500. Which it shouldn't with a big 60mm turbo and excissive intake manifold. these are not degreed, but neither where the BC's. I definitely plan on running a set of JWT's cam gears, but am unfamiliar where to go from there. SuperStreet did a nice write up on the same gears and cams in a ka i can base my reference off of. They ended up making a rather large adjustment. Someone spoon feed me!
Re: School me on cam timin'!
You will need a degree wheel, valve lash gauge, and cam card. It is not that hard once you get the concept. Basically, you put the degree wheel on, put the engine at TDC, use a pointer to point at TDC on degree wheel, then put gauge on intake bucket, and rotate motor and wait for the gauge .050 inch and get the degree mark off the wheel. Then look at the jwt cam gear and adjust the cam sprocket to advance or retard cam. Then repeat the steps again to make sure the cam opens at the desired degree on the wheel based off the cam card. I probably lost you cause I cannot explain well but hopefully I gave you an idea.
12.96 @ 116.36 - 2.1 60ft - 11/2011
13.1 @ 114 - 2.3 60ft - 8/2012
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13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel
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- 240sx Wannabe
- Posts: 118
- Joined: Sat Aug 17, 2013 10:38 am
Re: School me on cam timin'!
Correction, i actually have the old turboholics cams. From what i recall i believe these were identical to the JWT s1's? I have an engine builder who can help walk me through the process of degreeing them, i dont think i have the proper tools. If i buy the adjustable cam gears is there any easy adjustments i make guaranteed to help out? maybe advance them both a few degrees while decreasing overlap?
Re: School me on cam timin'!
I thought they were identical to BC and Crower 264 cams?
viewtopic.php?f=1&t=57359&hilit=turboholic+cam
viewtopic.php?f=2&t=61301&hilit=turboholic+cam
Every setup is different and with the cam gears, you may not get the correct timing but it will be in the same ball park tho. IIRC, my intake opens 4* after cam card but exhaust is spot on. I also drilled my own cam gears which adds to the issue. My head and block are decked and it look like the motor previously owner may have done the block as well. As long as the valves don't kiss, I am happy for the extra compression.
viewtopic.php?f=1&t=57359&hilit=turboholic+cam
viewtopic.php?f=2&t=61301&hilit=turboholic+cam
Every setup is different and with the cam gears, you may not get the correct timing but it will be in the same ball park tho. IIRC, my intake opens 4* after cam card but exhaust is spot on. I also drilled my own cam gears which adds to the issue. My head and block are decked and it look like the motor previously owner may have done the block as well. As long as the valves don't kiss, I am happy for the extra compression.
12.96 @ 116.36 - 2.1 60ft - 11/2011
13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel
13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel
Re: School me on cam timin'!
No, there slightly bigger... But what about huge cams like the jwt c78 288/280 with .480' lift, and also I found these huge cams for cheap pdm/colt custom cams 300 duration and .500" lift, which I believe are the biggest cams for the ka but im not sure... And I have no clue as far timing goes for those
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- 240sx Wannabe
- Posts: 118
- Joined: Sat Aug 17, 2013 10:38 am
Re: School me on cam timin'!
Definitely not the same, I mic'ed them and there's half a mm more lift on the turboholic vs my bc's
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- 240sx Wannabe
- Posts: 118
- Joined: Sat Aug 17, 2013 10:38 am
Re: School me on cam timin'!
These cams are for the more extreme set ups. Besides the point that our crank will shatter at the rpms High enough to put the cams to use, lift that high requires clearancing the bucket area as the lobes will make contact.321Ricky wrote:No, there slightly bigger... But what about huge cams like the jwt c78 288/280 with .480' lift, and also I found these huge cams for cheap pdm/colt custom cams 300 duration and .500" lift, which I believe are the biggest cams for the ka but im not sure... And I have no clue as far timing goes for those
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- Knows Some Stuff About 240's!
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Re: School me on cam timin'!
You definitely, definitely need to use a degree wheel, when installing cams, and yes you do need cam gears, or drill the whole on the gear.
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