Just broke in my untuned LSV and ended up hearing what sounded like lost motion assembly clicking and after replacing them with new ones found out that was not the problem. Took head off and found out what looked like pistons 1 & 4 burning good with carbon build up and pistons 2 & 3 like they were clean there was no carbon build up on them. Took block back to machine shop and they claim fuel wash down, oil being washed away from walls by too much fuel and creating this problem. . They claimed that was due to not tuning engine. I am pretty much new to the Honda game and do not understand, with each injector how are each tuned independent of each other. Was this cause of the problem? Is this true? I have AEM fuel rail / regulator, RC 310 injectors, Walbro 255 fuel pump, Skunk 2 intake, Crowers stage 2 cams, skunk 2 gears, P72 chipped computer, GSR head (port and polished with springs / retainer and 3 angle job), LS sleeved block with Darton sleeves in a 94 hatch. What ever the replie is it still sucks that I will have to bore and hone block and get new pistons. Any questions or additional info that s needed PM. Being that I have to replace pistons any recommendations are truly appreciated, machine shop was recommending Manley pistons 11.5:1. I have no other choice but to go up to 85MM or 86MM Pistons, and car once runing right will be running like a 125 shot. Thanks.


Modified by 94redhatchbackNYC at 8:49 PM 5/14/2007

 

You need to set the car on the dyno, no chip is going to guess the proper fuel maps without real time tuning, was it smoking? what was your break-in method?

 

so you ran that engine with 310cc injectors and no tune?

read this and save your engine from the same fate: http://laskeyracing.com/shop/breakin.htm

 

No it was not smoking. Yes it ran on 310 and no tune. Question= does tuning tune each individual injector or all 4 at the same rate. I just want to make sure that there is not something wrong with the injectors / fuel components. Thanks.

 

you probably need some kind of fuel controller. because those injectors and fuel pump seem a little large for what the ecu alone would give the engine at low speeds. durring cold startup i bet it floods the hell out of it. fuel controllers need to be tuned with a wide band o2 sensor mostly on a dyno by someone with lots of experience.

but on the other hand. i gained 18 whp and 10 more mpg with a dynotune.. so its not like your paying for nothing.

 

Did you do a proper valve adjustment?

 

bigger than stock injectors will not run correctly with a stock virgin ecu! get that thing tuned ASAP if you want to avoid the same problem.

 

To the original poster, all I had to read was the first 5 words of your post and it answered your thread title. You spent so much coin on this build, and no one mentioned to you that you had to tune it or you could face washing your rings or worse, blowing your engine. Tell me you at least had a basemapped chip for your mod list.

Like the previous poster mentioned, a stock ecu is mapped for 240cc injectors. 310 injectors require a new map, especially if you are trying to break-in new rings. And why do you need to go with an oversize bore and new pistons? You probably just need a hone and install new rings...AND A TUNE this time around. And we are talking, dyno tune with a program like Crome using a wideband sensor to dial in your air/fuel ratios. Good luck and welcome to the Honda world. That is an impressive build, should make you happy when tuned.

 

Sam as per machine shop yes I would have to go with bigger pistons due to light scratches on sleeve wall. And no those two pistons were scraped on sides so I do need new pistons. Really sucks, but we learn by our mistakes. And yes as soon as I get around to fixing block I will do a Crome tune. But quick question based on what is in my original post what recommendations you would say on the new pistons. Dont forget I am going to at least dump a 100 to shot in it. Thanks.