Offshoreonly.com - 502 EFI with side whipple help needed

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https://cimg6.ibsrv.net/gimg/www.off...01db185e10.png

That blue wire was tapped into the TPS extension and was running into the Piggyback harness.

you can also see i am holding the IAC extension, the purple and White wire were tapped into that extension and connected to the piggyback harness as well.

Yes that hose and filter are for my IAC vent. I believe the piggy back is wired that way so it can do its thing. I have the install pdf I can email you like.

Tim

Quote:

Originally Posted by articfriends (Post 4739505)

what kind of IAT's are you seeing? On the ones I dynoed with extra injectors the BSFCS even with "good" afrs everwhere kinda sucked (mid .650s to low ,700s at wot), that was tuned for 12.0 or so at beginning of boost and into mid 11.5s at top at 8 or 10 lbs of boost

nothing that bothered me.,my set up is far from stock.all the openings in the air flow thru the intercooler were opened up and smoothed out big time.most boost I see w/ the smallest pulleys are about 4.5-5psi.eventually I'll go to a 9-9.25" crank pulley.

Quote:

Originally Posted by 941 (Post 4739673)

Yes that hose and filter are for my IAC vent. I believe the piggy back is wired that way so it can do its thing. I have the install pdf I can email you like.

Tim

I have a PDF, thanks for the offer. I just need to get the tuning right now. I took out the piggyback and got it all cleaned up. Here is a look at my spark plugs. This was after about 2 hours at just idle.
And i did end up switching plugs to a NGK

https://cimg8.ibsrv.net/gimg/www.off...e48a34bdae.png

Quote:

Originally Posted by flawlesson24z (Post 4739665)

Correct. So what he did was wire (taped into) both Aux injectors to the #5 and #7 injectors. When i took off the plenum i seen the injector connector that comes from the piggyback harness zip tied and Not connected. The TPS and IAC extensions were there but for time reason he tapped into those wires and they were connected to the piggyback harness. It was a complete disaster.

i am trying to post pics but unfortunately it will not let me. I just don’t understand why the piggyback was wired and he tapped into other wires.

With the piggyback being wired and the injector plug not connect (because he tapped into the 2 batches) throw off the MEFI when they were trying to Tune?

So oit sounds like the piggy back was abandoned and injectors wired in, it was just never removed. It really WOULDNT affect the mefi tune, your tuner would just be tuning off the tailpipe readings yielded by the 10 injectors is all. Were his afr targets extremly rich? One mistake I have seen is IF somone put a crossover on and engine temp varies BUT they never blended out the ect table above 100 degrees it could make you run rich. Lets say it WAS 112 out, water was 90 degees, engine was running 140 or 150, he tuned for a target of lets say 11.5-1 under boost. Now, your running the boat BUT waters still "cold" compared to normal, motors running at 100 degrees, the ect table would richen it up by adding un-needed fuel. just a possibility, Smitty

Quote:

Originally Posted by articfriends (Post 4739736)

Great Point! That is something i have always wondered about with the crossover. In Havasu the water in currently still cold and when he tuned it last year it was in August and water was alot warmer. Also, Havasu is connected to the river in which the river water is ALWAYS colder.

Quote:

Originally Posted by 941 (Post 4739673)

Yes that hose and filter are for my IAC vent. I believe the piggy back is wired that way so it can do its thing. I have the install pdf I can email you like.

Tim

Hey Tim,

I would love to have a copy of the pdf. I can PM you my email address.

Thanks!