For the guys that went from a FI'd stock compression motor tuned with a Haltech to a FI'd lower compression motor.

Did you guys have to retune for the lower compression motor?

did you wait until after the break in(No Boost, 4000RPM Limiter enabled)?

Will the Haltech automatically compensate for a tune that was made with 600cc if you change them out for a 800CC and you change the injector size in the proper tables?

 

For non boost driving the same tune should be close enough (assuming your original tune was good). I always recommend having your tuner on hand for new engine first-start, as rich conditions can do unreversible damage quickly on a fresh engine.

If your tune was done in VE and is properly calibrated - changing injector flow and dead times for the new injectors should cause it to run the same after the injector swap.

I do recommend a retune on a new engine especially when changing internals and compression ratio.

 

Car was only dyno tuned it hasn't even been on the road yet.

Would another option be to install the stock injectors and just use the factory ECU for the break in?

I won't have access to my tuner for the first start since he is 2 states over.

 

That would work as well so long as you have the MAF and everything the stock computer requires. I would also suggest having an aftermarket wideband(s) in place for first start so you know immediately if something is wrong and it is overly rich.

 

I do still have MAF connected to the stock wiring.
I got the Haltech AIT Sensor connected directly to the Haltech EMS.
I got the AEM Wideband for awhile so no issue there and
I have the CJM Fuel Return System at Stock Fuel Pressure.

Thanks for the info Hal.

 

ya but did you cut out the stock AIT to wire in the haltech AIT?

 

Nope ran new wire to the Haltech for the AIT



Which I need to clean up and make it look better

 

Your ignition timing won't be optimal with the new lower comp ratio.

 

Will it damage the motor?

or am I just looking at it as a performance loss?

If it's a performance loss I really wouldn't mind
since I won't pass 3-4k RPM during the breaking.

From what Hal is saying there should be no negative
for me to be running stock injectors with stock ecu
as long as I don't get into boost

Plus I need to get my state inspection as long as I'm able
to get the car OBDII ready I will be happy

Compression is 8.8 and the only other thing is JWT S7 cams

 

No, it won't damage it at all. You'll just be leaving some hp on the table, so to speak.