short and sweet : will forged pistons in my h22 make the stock knock sensor (2000 lude) think i'm detonating and retard the timing?

 

no. you better resleeve the block if you want forged pistons though.

 

yeah, i was planning on that. sending the block to golden eagle for sleeving and decking, but i can't decide between arias 9.6:1 pistons (87.5 mm), je 9:1 (87mm) or je 9:1 (90mm) pistons. what's the increased likelihood of headgasket failure with the 90mm bore?

the arias pistons are cheaper....

 

How much do they want for the 9.6:1's? I am sending my block to them next week and I need pistons. The je's in 87mm are 9:1, I was thinking going a bit higher, we have 94octane everywhere.

 

are you boosting? i've only got 91 octane out here, so maybe 9:1 is the right thing to do...

ge has a "package," sleeving, decking, bore & hone, pistons, rings, and wrist pings for $1390. i assume that varies depending on motor, this is of course for an H22A4. same thing minus the pistons was $975. $400 bucks for the pistons, rings, and pins seems pretty cheap to me. je is more.

 

while i'm at it, would it be worthwhile to throw in another $330 and get some eagle rods? only looking at 9psi of boost, around 250whp.

 

if you're only going to boost 9 psi why even get forged pistons and resleeving? inline pro has an h22 turbo stock motor except for metal head gasket running like 18 psi (<<<not positive on that figure but it's up there). if you're going to boost more, and you have your mind set on getting forged slugs and resleeving, then you should go with the 87 mm pistons. you prolly won't get good life out of your head gasket with a 90 mm bore. yes while you're at it you might as well get rods.

 

well, everything is back together and running, still breaking it in, but i am getting a MIL with code 0325 (knock sensor circuit malfunction.)

i assume that the sensor got broken in some rough handling when the block came out? or else the wives tales about stock obd2 knock sensors and forged internals are true.

 

I don't think you need to spend all that money on 9 psi. Just my opinion.
jason phan


[Modified by Ltech, 4:29 PM 6/19/2002]

 

did i ask? maybe you can tell that to the ±50% of boosted prelude owners (<10psi) who have broken their ring lands?

 

I'm having the same problem on my car right now. I don't know if this is going to work, but I'm taking the knock sensor off of the block but leaving the wire connected. I'm trying to trick the sensor so it doesn't turn on my check engine light and retard my timing. They say you can lose up to 40-50 whp with the knock sensor retarding your timing. I'll let you know tommorrow if it works.

 

what is a code 0325? is that an obd2 code or something? do you have the knock sensor hooked up? running to the correct ecm plug? i have je pistons and i don't get a knock code.

 

Yes, and the truth is, it will cost a grip more to fix/replace a block should damage occur. I've spent more money fixing my bock than sleeving it.

 

It is an OBD-II code for faulty knock sensor.

 

Ok, so I am not the only one. I have a OBDI car I am currently having problems with. I have a Hondata chip installed, and I guess the codes are not there, but my check engine light comes on almost right away after I start the car. I have forged pistons installed. You can put a resistor to ground which is probably what I am going to do, instead of just leaving the sensor hanging there. I will research it more, let me know if you want to know the outcome.

 

The K/S is affected by the forged piston slap on most pistons, particularly low silicone pistons like JE/Weisco. Your ECU may retard the timing on occasion, mistaking slap for knock.
If that's all you need to know.. there's your answer. It can happen.