My draw through turbo
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Re: My draw through turbo
It appears your using an 009 distributor. The advance in these can vary a lot depending on the manufacturer. If your total centrifugal advance is 24, and you set the total advance at 24, your idle initial advance is 0. That will cause your entire advance curve to be 10 degrees retarded until you reach 2800 RPM. Try this. Put away your timing light and hook up a vacuum gauge to the manifold. Move the distributor until you get the highest manifold vacuum. You'll probably have to turn your idle speed down and maybe lean out the idle mixture as you go. Now see what your idle timing is set at with the light. It will probably be somewhere between 10 and 16 degrees depending on your cam and compression. Subtract that amount from your centrifugal advance, and in this example, you get 12 degrees. Add weight travel stops of some kind so advance will only advance 12 degrees centrifugal, for a total of 24 degrees. I see guys chase their tails changing carb jets when they should be looking at their ignition advance curve. You would be much better off with a distributor that incorporated a port vacuum advance along with a centrifugal advance.
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Re: My draw through turbo
I see what your say and that's what I have done. My 009 had 24 degrees of advance and I used to set it on my N/A engine to 32 degrees BTDC @ 3000rpm but I I have limited its advance by locking a screw in it ( witch I can't remove) to only 14 degrees of advance. But do I now set that max advance of 24 BTDC @ 3000rpm or @ 2500rpm ?
Now by my calculations this 009 distributor when unlocked on my N/A engine when set to max advance 32 BTDC @ 3000rpm would of hit 24 degrees BTDC @ 2500rpm.
So should I now be setting the max 24 BTDC @ 2500 or 3000rpm?
I have also got a SVDA distributor but there is no vacuum port on the carb to connect to and when connected to the manifold port I get max vacuum advance when at idle
Now by my calculations this 009 distributor when unlocked on my N/A engine when set to max advance 32 BTDC @ 3000rpm would of hit 24 degrees BTDC @ 2500rpm.
So should I now be setting the max 24 BTDC @ 2500 or 3000rpm?
I have also got a SVDA distributor but there is no vacuum port on the carb to connect to and when connected to the manifold port I get max vacuum advance when at idle
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Re: My draw through turbo
My bad my timing gun is at fault. Used my dads gun and got a reading of 8 degrees BTDC at idle but only 18 degrees max advance so I've bloody limited my distributor to only a 10 degree advance and there's no way of correcting it. Anyway I now have a 15 degree advance at idle witch is giving me 25 max advance at 2500rpm and all is good no flat spots at all and is so pleasant to drive
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Re: My draw through turbo
Glad u got it sorted,
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Re: My draw through turbo
turbos are the future
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Re: My draw through turbo
Is it worth wrapping the exhaust or not people?
- Chip Birks
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Re: My draw through turbo
Is your exhaust stainless? I almost ruined my expensive steel A1 turbo header when i wrapped it. I'm sure things were a little cooler, but it definitely limits the life of your exhaust. If you need it use it, but just realize that your header has become a consumable and will rust away.
- petew
- Posts: 3920
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Re: My draw through turbo
There is a way around that. Have the header ceramic coated first. It's not cheap exactly, but it will help.
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Re: My draw through turbo
Yes the exhaust connector pipe and the last part is but the 4 into 1 header is not.
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Re: My draw through turbo
Maybe ok in the 'Desert'? but we live where it's just too Humid
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Re: My draw through turbo
Going to leave the exhaust wrap. What clutches and pressure plates you lot running ?
I've definitely burnt my out and it's not that old done around 2000 miles on it in total, was just driving around at 70mph @4000 rpm then noticed the rpm was holding still and the speed was dropping off
I've definitely burnt my out and it's not that old done around 2000 miles on it in total, was just driving around at 70mph @4000 rpm then noticed the rpm was holding still and the speed was dropping off
- Chip Birks
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- Joined: Wed Mar 12, 2008 5:59 pm
- petew
- Posts: 3920
- Joined: Sat Oct 07, 2006 4:05 pm
Re: My draw through turbo
200mm Kennedy stage II pressure plate and stock German disc. The pressure plate is probably overkill, but I wanted something that was tough enough to deal with all-day dumping the clutch at autokhanas. The advantage with a stock "rag" disc is even if it slips when hot it will grip again once it cools down. A good friend with a 400hp blown V6 in his bus ran a similar setup and turned me onto it. Hasn't slipped yet and my 13yo daughter has driven it, so it can't be too heavy.
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Re: My draw through turbo
I'm running a 1700lbs. / stage 1 with a sprung center 4 puck ,,1825 lbs bug with me in it, holds great, even with slicks
- rubenski
- Posts: 2033
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Re: My draw through turbo
Will you still destroy you exhaust with wrap if its stainless?
Better to be blown than to suck!