V2Rocket

anybody in socal have an ostrich i can borrow..lol

Rogue_Ant

The ethanol sensors that I've looked at output a frequency, in accordance with ethanol content. These will not naively hook up to DME or most piggybacks. However, with a basic freq-to-volt conversion circuit, hooking an E85 sensor to the DME is do-able...
But really, I haven't had that much of an issue with drifting tune using E85 year round here in Colorado. And not enough to justify the $400 sensor, and the time to bother with making the circuit, then changing DME SW to use it. I guess if it that much of a concern, I'll look into it.


-Rogue

333pg333

So do you monitor it or just leave it as is and monitor knock counts or????

Rogue_Ant

I monitor AFR and knock of course (EGT as well). Perhaps a little global change is needed between winter and summer blends, but otherwise I don't change my tune much (not for ethanol content anyway).

333pg333

Ok thanks R.A.

sciroccio

If I made the Turbo+ E85 project, could I use 944 2.5 N/A engine with stock CR (10.6:1) ? Would the standard pistons work, or would I have to get the performance ones?

gt37vgt

Yes it will work just don't get greedy and ask for more than 400hp and every thing will be just peachy

Rogue_Ant

That high of CR, I wouldn't push much past 15psi... The NA pistons simply aren't as tough as the turbo ones.
But that should make some good power, and have great drivability - I know mine does, and I'm running a full point less CR then that

333pg333

Nice! Must be very responsive. Get some in car video Joshua.

blown 944

Depends on the year of engine. The early engines used forged pistons, while the later used cast. I have ran both and broken the later ring lands at around 25psi.

It does make a nice little difference in drivability using the higher compression. At this moment I am swapping my high compression engine into my driver car and using the lower compression engine in my lightweight. I was just doing a clutch, but have decided to have a little more fun too.

BC

With no detonation, I don't see how the pistons would come apart.

blown 944

weak ringlands between the top and second ring. The added pressure from the top ring ***** against the land which is not very strong on old cast units

I have a full knock monitoring setup on, and they do break due to pressure.

Rogue_Ant

Ring-lands aren't as strong/thick as turbo pistons. At a point they will fail.

*Sid beat me to it*

sciroccio

I have the turboS pistons with 8.0:1 CR. To my understanding, the CR is too low for the E85 fuel. Also, you say that they are stronger than the N/A pistons

95ONE

Side skirts also have less material giving less "rock" controll. not sure if the pins are pressed or full floating.. also makes a big difference.. considering 951, im guessing floating.