Tuning issues.. Jake can you advise?, advance curve or jetting (that is the question) |
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Tuning issues.. Jake can you advise?, advance curve or jetting (that is the question) |
brant |
Jun 9 2009, 12:52 AM
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914 Wizard Group: Members Posts: 11,632 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
I finally got my latest project running but not well enough
I need to do a little tuning... its a 1.7 motor with a cam (don't know the specs of the cam) from the previous owner I can get leak down/compression, but don't have them at this moment. I also don't know the compression, but it is mild... probably stock the P.O. claims it was rebuilt and I believe it I took all of the tin/push rod tubes off, and it looks to have been rebuilt with out worn/shot stock cam lobes and with lifters showing no significant wear doesn't seem to burn-smoke or leak any oil at this point. Its running 40mm dual webers, currently testing at 3300 foot altitude (motor came from a running car at about 5500 ft) I rebuilt the carbs and the jetting is: -28mm (chokes) main venturis -2ndary venturis 4.5 -main jets 115 -air jets 200 -emulsions F11 -acc. pump ball jet 50 -acc. pump towers 50 -idles 50 I've never carbed a 1.7 before The motor came with a 009 distributor and points I ditched it and put in a L-jet 914 (1.8) distributor with points, blue coil, and no retard/advance lines hooked up the cap/rotor/plugs/wires are all good-new car idles smooth, pulls fine from standing, and then stumbles mildly from 2000 - 3000 the car clears out and runs great at 3000 or 3100rpm timing is currently set at 29degree's, but this is my norm for altitude. dad and I are in disagreement about the cause he thinks its too rich for the tiny motor I think its a distributor curve issue Jake, do you know? I have a Djet distributor available easily... or could put the 009 back on... or think maybe I should buy an 050 somewhere to see if the curve is actually the problem We discussed buying 110 mains also to play with it... thanks in advance for any advice from the guru's out there brant Attached thumbnail(s) |
Gint |
Jun 11 2009, 07:22 AM
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Mike Ginter Group: Admin Posts: 16,082 Joined: 26-December 02 From: Denver CO. Member No.: 20 Region Association: Rocky Mountains |
sorry for not calling I'll call tomorrow if thats ok with you after 3 good again? I have that vacuum port on this car also which side of the dash pot do I want to hook it too? (one hose barb is slightly bigger... like 3mm vs 4mm) I think I'll stick a distributor in before I buy jets... (cheaper) then I'll buy jets.. mains and idles any local shops for jets around? Is randy's VW still open? brant No sweat. Today works. I'm cell-less until this afternoon. See my email. I'll get a pic of one of my carbs or if we can meet up I can drive the 914 and you can see it for yourself. One of those vacuum ports on the dizzy can is for advance and the other is for retard. If memory serves me, advance pulls away from the dizzy and retard pushes. Based on the angle you can figure out which is which. Advance is usually the one sticking out the end and retard is in the side of the can. And then you can always pop the cap off and figure it out. Randy's is long gone. Painter's will have some and even IPW has a selection. That's where I got my last set of idle jets a couple of years ago. |
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