Ive been haveing issues with mine in a 51 chevy truck. My buddie found something online swapping one from a 80 chevy 250 motor. it says there is a little modification that needs to be done. Has anyone tried this and if so how difficult is it?
This is what he must have seen. Doesn't look too difficult. http://www.stovebolt.com/techtips/hei_conversion.htm
The 216 camshaft is steel, later cams are cast iron. I'm not sure if this applies, but when swapping a 235 (2nd gen.) distributor into a 216, the 235 distributor gear (iron) must be replaced with the 216 distributor gear (steel).
Stovebolt stories from someone who never did it because he's forgetting an important part ...I was doing the conversions around 1999 with hand tools and selling them.You will have to shorten the distributor shaft about 3/8 inch and then reprofile a tang to fit in the oil pump properly.If you don't do this the gear won't be lined up properly with the cam gear.Just match the old and new side by side..... About the gear and cam material...By the late 60's GM parts manuals only listed one gear from 1940 ish to 1962.So either it's not a problem or GM didn't think so...
Ill have to use hand tools also. My buddy found this http://www.chevytalk.org/fusionbb/showtopic.php?tid/277820/post/2201990/hl//fromsearch/1/.
Just remember that 216 had a very aggressive advance; That HEI only has 20 @ 4200 The original called for 5 initial plus 36 distributor at 3500. You can tweak the HEI to get around 30 at 3500 and run 11 initial. This mod allows the weights to retract more. See; http://www.pontiacstreetperformance.com/psp/distcurve.html The VC1835 AS2 1975-76 350 Olds 5.5-7.5 12 @ 15-17 has the right vacuum level but 2 x 12 for 24 crank advance. A Crane advance limiter is like 3 bucks, The second notch from left would give you 20, or whatever you need.
When the gas prices blew up in the 70's we got interested in fuel economy. Had to learn how to tune an HEI. We didn't have the easy stuff so we would get the right Vac in Hg and then use a screw to limit the travel in the slot. We did grind the center plate and being a GM driveability tech with a distributor machine we played with all kinds of tricks on the mechanical advance. A 375 center plate with a 109 weight gave 26 crank, and you could trim the center with a file to get a few more. We also wired up a relay to the 5 terminal EMR module to give us 10 degrees cranking retard. I think we would run 20 initial, 18 distributor on a 250 with a speedo cable made up with dials on one end and double dd's so we could dial in advance limit and APT or lean Stop from the cockpit. We would go for max vacuum with timing, then as lean as it would run, then more timing. This new stuff is just a lot easier but I would replicate what Chevy did back then instead of reinvent the wheel. Hoop
That looks like a pretty good way to go; ) Here to: http://www.jalopyjournal.com/forum/showthread.php?t=679518&highlight=hei But MO is right about the steel gear, you may be able to swap them out. Langdons sells a real nice stealth HEI for a good price. My timming worked out fine...the one i bought had an adjustabe vacuum can.
I took off around a quarter of an inch when I put the dust in its sitting about a half inch high and not engaging the oil pump. But the gear is engaging any ideas what I need to do
Look at the position the oil pump needs to be at when you install the distributor. Thake a long skrewdriver and clock the oil pump drive to that position.
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