Does timing affect engine temps?, I swear my engine is running hotter... |
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Does timing affect engine temps?, I swear my engine is running hotter... |
pete914 |
Jan 31 2008, 06:33 AM
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#1
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Member Group: Members Posts: 178 Joined: 21-August 07 From: east coast Member No.: 8,025 |
So,
I'm running a 1.8L stock Vacuum advance dizzy with single weber (i know...not ideal) and as I've learned the advance curve is wrong for this setup and I have pretty bad lag now before 3000rpm. I swear the engine is running hotter now. Is it because the timing is too retarded in the lower rpm range? does that affect engine temperature? Anyone running a similiar setup with a suggestion as to where to set my timing to get better performance? I don't rev it up much past 4500 Oh, and I just ordered a a centrifugal advance dizzy, if someone is using one of those with a single carb and is having luck, please tell me your settings. Thanks. |
Twystd1 |
Feb 1 2008, 03:54 AM
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#2
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You don't want to know... really..... Group: Members Posts: 2,514 Joined: 12-September 04 From: Newport Beach, California Member No.: 2,743 |
OK,
Hers my take on this stuff. I don't play with stock engines very often. Your engine ain't stock. It has a weber 32/36 DGV or DGAV more than likely. Since it ain't stock. Forget about stock timing marks. You have no clue to WHAT YOUR ENGINE internals ARE unless YOU rebuilt it or have reciepts from the PO. So when ya have a non stock unknown engine. I set the timing to where the engine runs right. Period. I first make sure the dizzy is in tip top condition. New springs on the advance mechanism. Take it apart and clean and lube everything. If the dizzy has a worn bushing. I toss it on the pile or rebuild it if possible. In a perfect world. You would put this dizzy on a distributor machine and make sure the curve isn't notchy and it starts at the right RPM and finishes (all in) by 3400 RPM or a bit sooner. (3.2K - 3.4K) Or buy a Mallory and be done with it. Once I have a known good dizzy. I simply install it like the factory manual says to. Or use Jakes description above. Either way. Put the sucker in correctly with the little spring under the dizzy shaft. If it's missing. Get one. New points or pertronix or whatever. I set points with a dwell meter. I don't use feeler gauges on points. Too inaccurate if the points are used at all. I check to see if the plugs, cap, wires etc are in good cosmetic order. (Use an ohm meter on plug wires. My wires see less than 1K ohms per foot) Once this is done. I make sure I have fresh gasoline. In fact the same gas I am gunna run in this engine most of the time if possible. I then start the engine. Get it timed by ear so it idles pretty dam good. If it ain't fresh gas. Your wasting your time. I find TDC. I point the rotor to Number 1 on the dizzy. I keep the dizzy loose enough to turn it by hand. Yet not so loose it will turn by itself. (Stiff turn) Next: Start engine. Move dizzy a little till it fires up and runs. I get the car warmed up. I drive around the block a bit to clean up the plugs. Then I purposely try to lightly bog the engine in 2nd and 3rd gear to listen if it pings or not. I get out of the car every 100 yards or so and keep turning the dizzy till there is an audible ping in the engine when it is bogged. Att that point. I KNOW I am too far advanced. Then I simply back off the timing till it stops. Then I back it off a hair more. For the moment. I am done timing my engine. Now I go higher speeds and see how it's running. I watch head temps and oil temps. If anything is out of the ordinary. I tweak the timing until I find out it's not a timing issue or little sucker runs just right. I can tell you that you are now close to what works for your combo. If the ambient air temps get much hotter than your original setting. (Like summer) You may have to back off the dizzy. (Retard it a bit) Shit gas will have the same effect. Once you have ascertained what works. Then break out your timing light and see where you are in comparison to your stock timing mark. If it's a mile off. You have something mechanically screwed up. (wrong fan, wrong mark, bad dizzy install, etc) The above is all you have to work with unless you have a chassis dyno to play with. If you find you need to sync your carbs or do some tuning outside of your timing. NOWS THE TIME TO DO IT. As you will probably need to time your engine AGAIN as other things that effect proper combustion have changed. Once you have it all dialed in. Set it and forget it. Until you change something else. NOTE: If you aren't absolutely clear on what pinging sounds like. (Pebbles in a tin can) DON'T TRY ANY OF THE ABOVE. FIND SOMEONE THAT KNOW THAT SOUND VERY WELL. This is all backyard mechanic stuff. And it works. Now: Anyone else have any other options for this fella? Clayton |
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