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TR4/4A TR3b / TR4 distributor curve

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tdskip

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Hi guys. I'm about to pull the positive earth distributor from the TR3, which has a TR4 engine, and send it off to Jeff at Advanced Distributors for a rebuild and Pertronix install.

Does anyone have the proper curve map for Jeff?

She is a stock, somewhat tired, motor although her compression is good.

Thanks!
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif If Jeff is as good as everyone claims, he will have an updated curve more suitable to the fuel available today.

But I think original for a TR4 would be a model 40795 (or 40795A), which I have as 1 degree @ 350 rpm; 6 degrees @ 600 rpm; 10 degrees @ 1200 rpm (distributor degrees & rpm, advance numbers +/- 1 degree).

Vacuum unit should be a 54413565, rated 2-6-3 (meaning advance starts at 2 inches Hg and reaches 3 degrees by 6 inches Hg).

PS, Don, doncha just hate it when you hit the caps lock & don't notice it until too late /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
Jeff has the curve information for about any distributor ever made.

It's more important to tell him everything about your engine and your intentions going forward, so that he can set it up properly from the start.
 
Yep - the misunderstanding was all my fault. I DO have a great street curve for the TR3s. What I had asked was something I didn't explain very well. I ask all my customers to fill out a "curve worksheet" from my website:
https://www.advanceddistributors.com/Curve%20Worksheet%2007.htm

That gives me more than enough info to determine which curve to use. I modify the TR4 curve and will use that in this case, with the stock vacuum advance. Hopefully this dizzy has the TR4 advacne assembly already installed. I like to use the 25D advance assemblies in the TR3s because its far more consistent in operation than the DM2 "toggle type" advance assembly. That consistency is how I manage to obtain the steadiest possible idle and reliable performance. If this distributor doesn't have it already installed, I have the assemblies here ready to use!
Jeff
 
Jeff, been watching your posts.Maybe you can help. I am doing an MGA w MGB 5 main/alloy head/mikuni-44 engine/LH OD conversion. I dont want to use the electric tack from a B. So I have gutted a TR6 dist with tack drive and put the MBG dist parts in it. I think the weights and springs are incorrect. I cant get the dist to work properly in the B's engine. Just pops/backfires. If I send it to you can you set it up to B specs?
 
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