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E85 carb mods?

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Not specifically, but it shouldn't be too hard. You'll probably need to press the jets lower in the main body, with some experimentation to find just the right position (so you can dial in the mixture with the needle adjustment).

Some years ago I tried running my TR3A on E100. It actually ran pretty good with the jets lowered about 3/16" (on SU H6 carbs, so not directly comparable to your ZS carbs).

But I assume you realize that power output will be down and fuel consumption up. And of course after the changes, it won't run right on E10 or E15.
 
I just found out the head on the car I purchased was milled a lot. If I try to put the timing where the engine runs good, it pings a ton without a bunch of 110 octane added to 92 octane.
I purchased this car from a auction and it wasn't running, previous owner rebuilt the engine but only drove it about 50 miles before some electric trouble, then it sat for many years.
So I need to either run some good gas or reduce the compression, I did a compresion test and I got 185 PSI in all the cylinders.
Does anybody make a thick head gasket?
And thanks for the sugestion on the jet adjustment. Are there larger jets and rods large enough to increase the flow 30%
 
W/ E85 you can run higher compression. It must have been cut a lot.
 
MGTF1250Dave said:
I think this is a link to the steel shim you need to lower the compression on your engine:

https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=65584
Click to expand...

Er, no. For one thing, that is a 4-cylinder gasket, while the OP has a 6. For another, it crushes to only about .010" thick, not enough to lower compression by any significant amount. It's more commonly used to raise compression (since it is thinner than the standard head gasket).

It was originally part of a compression lowering kit for the 4-cylinder motor; but the actual compression lowering was done by a steel plate some 1/8" thick. The shim steel gasket just sealed between the plate and block (or head, whichever side didn't have the standard composition gasket).

However, I'm pretty sure Mordy could put together a similar kit for the TR6, for not too much money. It would be a special, though, so you'd have to contact him directly for availability and pricing.
https://www.headgasket.com/

But since your head has already been goofed with, I'd probably look at enlarging the combustion chambers first. Also round off any sharp edges, as they promote detonation.

You might also try looking for an "octane improver" that contains MMT. When I was running a TR3 head that was shaved too much, the engine seemed to really like MMT. The deposits would build up and actually reduce the requirement over time; after 10 or 20 tankfuls I was down to only adding about 1/10 the recommended amount. But it didn't work nearly as well for my buddy with the supercharged Miata, so YMMV.

I'd also try modifying the ignition advance curve, before using the compression lowering plate. Lower compression is bad enough, but the plate also reduces quench, which reduces efficiency even further.
 
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