13.5:1 E85 street/autocross

I'm picking my engine parts up from the machine shop Monday. A bored 75.5mm, decked, D16z6. With ARP equiped resized stock rods, NPR P29 pistons, micropolished crank & cut down OEM pulley, crank & 8lb flywheel balanced to 0.02 grams. The head is at a specialty Honda porter getting a serious porting, 3 angle, Supertech springs, new seals & guides. Then adding ACL bearings, 272 cam,60mm Tb port matched to intake & RDX 410cc injectors .This will be joined to a new SI carbon sycro lsd trans & it's all going into my '76 Civic which already has BCR coilovers, big front discs, rear discs & polyurethane bushings. The final compression will be @13-13.5:1. I will be getting it tuned but for the breakin I have some questions. I have a gas wideband meter & do I understand correctly that since e85 stoic is @ 9.5, when it says 14.7 which is for gas, since it's e85 it is actually 9.5 stoic is stoic. Or did I not understand what I was reading? I understand the 105 octane, better forgiveness for lean, @30% less energy hence the need for more compression, not sure about how to read the meter. I also need to get basemap to break it in before tuning.

See if you can set your meter to lamda. Less BS-ing with conversions.

Sounds like a nice build. Should do 150+ to the ground.

As a rule of thumb, you can never have too much compression, just too little camshaft.

With a decent camshaft, 13.5 should be able to be run on pump 93 with those teeny tiny little bores.

So if the meter is set to lamda, it would show lamda for the e85 which then should be @9.5. Looks like most leave it & tune for 14.7 then just tune to that.

Converting gas to e85afrs can be a pain. Lambda is nice as you can think universally of it regardless of fuel type. 1 is stoich, less is rich and more is lean. .75-.85 is max power rich on that fuel, which on a gas cal wb is 11.5:1 give or take a little.

Knurled wrote: As a rule of thumb, you can never have too much compression, just too little camshaft. With a decent camshaft, 13.5 should be able to be run on pump 93 with those teeny tiny little bores.

With e85 @ 13:1+ & the law of diminishing returns sets in. 11-13:1 is where the big gains are. Yes but where I live there is 91 & there are 2 stations with e85. So e85 it is.
I can set my AEM WB to Lambda so will be just like gas.
Yes 11.5 rich power seems to be the common opinion.

I tuned for .85 Lambda on my E85 D16 and advanced the timing until it stopped making power. Never did get knock, and that was boosted.