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Timing map help?

To: "Datsun-Roadsters@Autox. Team. Net"
Subject: Timing map help?
From: "Daryl Smith" <drlsmith@telus.net>
Date: Sun, 8 Jan 2006 11:21:28 -0800
I was having some overheating issues on my new engine (before Xmas) on the
initial startup.
First startup it went to about 240 deg (took about ten minutes) before I shut
it down.
Second startup it peaked just below 220 deg (fuel adjusted rich and timing
adjustments) and I ran it for about 15 min. This is still too hot.

I noticed when it was running that only the passenger side of the radiator got
hot?
I've since swapped in a known good radiator, but not sure that is the biggest
issue. (haven't fired it back up yet)

Engine is R16 block, G15 crank, custom pistons, 38mm SU's (temporary).
MegaJolt/Edis ignition. (Megasquirt swap soon) Classic Instruments gauges.

I know I will be adjusting the fuel again, starting from scratch (mixture nuts
all the way in, then .......)

My timing, without vaccuum, is programmed for:
 16 to 36 deg btdc without vacuum,
 24 to 44 deg btdc with vacuum,
from idle to 3000 rpm.

For the second startup it was at 27 deg BTDC running in the driveway at 2000
rpm.

My mods prevent me from putting the dizzy back in (butchered dizzy mount) to
check dizzy timing, Soooo.....

I was wondering if anyone knew the timing curve of the stock dizzy, with the
vacuum hooked up, between idle and 3000 rpm?
I am thinking the above timing may be too conservative (retarded timing will
overheat the engine) and would like to know what the stock would be at........
(I know, it would have been so much easier if I would have thought of this
BEFORE I started cutting!! :oops: )

I have retorqued the head, Will reveiw how to adjust the carbs, and will
borrow a infrared thermometer for the next startup (soon), but wanted to check
on the timing issue,...... and any other issues I  may have overlooked.....

(this is also at http://www.311s.org/phpBB2/viewtopic.php?p=22875#22875 )

Thanks a bunch....

Daryl




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