RobertWolfrays

Hi guys,

Just a quick question. My engine has the Mahle's long rod setup, 87.25mm bore with 12.5:1 compression, ap1 rods with ap2 crank. I'm going to use an EMS-4 to run the engine, but I don't have my patch harness for it yet. I was wondering if I could use 93 pump gas and an octane booster, or some kind of race fuel to run on the stock ecu. I need to refinance the car on 4/15 to get some equity back out of it and the back wants to see it running. The only driving I'd do would be limp it to the bank and back, until I could install the EMS-4. Is it possible?

Thanks,

iDomN8U

I'll take a guess at this and say no. I'd tow that car to the tuner with the EMS in hand and let them set it up so it doesn't explode.

Hate to see all this work go down the drain because of a small inconvenience and no patience.

Save up some funds, postpone the refinance and get it done right

RobertWolfrays

I'd love too wait, but my last payment on the car is 4/15, so I have to get it refinanced by 4/15. I've got the patch harness on order and hopefully I'll get it this week. This was just last option type question.

iDomN8U

I don't see why it wouldn't work. Physically it will work with the stock ecu and stock injectors.

I would be concerned about stock ecu, ignition timing and afr. The stock ECU should pull timing on pinging but who really knows what it might or might not do.

As long as your not going into a closed loop, the ECU will try to compensate the fuel to meet targets. Maybe the ECU will throw a CEL

s2000Junky

At 1.5 bump in compression and 93OCT id be surprised if you couldn’t just run the factory ecu timing curve period, along with the added fuel. The 11:1 comp is meant to run on 91. So would I limp it around without concern? yep. Would I drag race the guy at the light on the way to the bank, maybe once lol, but I wouldn’t advise it. As mentioned, if you stay in a light load on the motor/just run in closed loop, which is no more then about 35% throttle, then you should have no worry. The first place the motor is going to knock/detonate first is under high throttle load or where it makes peak trq at WOT.

06Estukay

You'll be fine. Avoid high load at low rpms.

My motor at 12.5 compression and 94 octane was not knock limited when using ignition timing values above stock (at upper rpms at least).

Again, keep a light foot between idle and ~4k. This is where you'll mostly get knock.

ShocK

Always let it warm up before driving too, my engine builder said you can score cylinder walls if you hop in and beat on it, not that you would now, just future reference. I am VERY curious to see what kind of power you make. I am about to take my engine out and install those exact pistons and ACL race bearings.

yamahaSHO

*Open Loop



If any doubt, although you should be able to log knock, put in some race fuel.

wadzii

those pistons are VERY thin under the intake valve relief, they will probably break. I'd ceramic coat the tops so maybe they will last a little longer.

It'll run good enough on the stock ecu and injectors

This combo works pretty well it just sucks that the pistons are so fragile.

Aurex

Would Mahle be able to make a custom piston that would have more material left after the relief cut out?