ggino85

iTrader: (1)

Ok so i have confirmed that the engine is bored .010 over. (the pistons say .25mm on the tops). which i was really happy to find out because the engine was rebuilt like the previous owner said. but then i have been reading that it is not good to bore/hone a 98 block more than .005 over........so am i screwed? i already installed a ls2 timing chain and new sprockets, i have 243 heads to put on and also have ls7 lifters with ls2 lifter trays. i was gonna buy a new oil pump but it looks like the one on there has recently been replaced......now im almost ready to start putting her back together and im wondering if i am doing this all to a motor that isn't going to last please give me your opinions and if anyone has a bored/honed block i would really like to hear some details like how long its held up ect........

reeperz28

iTrader: (1)

I've have read on here about guys bragging with cleaned up cylinders with .11 bore over boosted. In my honest opinion I'm sure it will be fine

Darkman

iTrader: (2)

For what it is worth - according to Jospeh Potak's LS engine book, the maximum overbore on 1997-1998 LS1 blocks is 0.007 inch (3.905-3.898) while later blocks were good for 0.012 inch overbore (3.910-3.898).

ls1 1990 VN

I am running a pre 02 block and it's on it's 3rd hone, i am running 3.908 pistons & have been now for 3yrs, i road race on occasion & also 1/4 ml. There have been zero issues regarding piston/bore size.

BlackScreaminMachine

iTrader: (17)

You can certainly push it but your on the ragged edge.

farmington

iTrader: (14)

Do you realize that .010 over is only .005 off all around. A piece of paper is .003 thick. Think about it. You're OK. Don't worry about it.

tim99ws6

iTrader: (31)

if it's a thin walled 98 or older block....I wouldnt run any kind of big power through it. It's a gamble regardless, but at lower power levels, it's probably fine.

redbird555

iTrader: (14)

like I told you on ls1.com man, a lot of people go that route hell if you have a worn blocvk and then hone it .005 your probably around .010 anyway i wouldnt worry. Now I wouldnt go running 15lbs of boost or a 200 shot on it but for a basic blvd bruiser with a cam and such i wouldnt worry

ggino85

iTrader: (1)

i started this thread before you posted that response. the post you answered me previously about was about the pistons being .25mm oversized (which was very helpfull, thank you), it is what confirmed for me that the block was bored/honed .010.... you also told me that .010 was the max bore for an ls1 and i was thinking AWESOME! but then i reading that some people say you can not bore 98 blocks that much, so i started this thread to get a bunch of opinions

im really glad to read everyones responses! its put me at ease......im not going to run any kind of big power, im probably gonna even keep the ''baby cam''. im in Cali and i dont wanna deal with smog at this point.....

XtraCajunSS

iTrader: (2)

Those recommendations are meant for GM service overbore with STOCK type reliability so GM can stand behind the repair. I can assure you, GM has plenty of safety factor built in for warranty concerns.

That being said, I have gone up to .020" over on those blocks for my personal use with no issues. I wouldn't do this on a customers build for ethical reasons but on my own stuff, I wouldn't hesitate. You are talking about a .003" difference in bore. I've seen blocks with more core shift than that!

Shane

redbird555

iTrader: (14)

Ya man sorry if my comment came off as being a little dickish but shane is right the .010 is just a safety thing for fm. I didn't mention the thing about it being a 98 block because I didn't see it being a big deal since your not going to be going any bigger lol

ggino85

iTrader: (1)

no worries redbird, that makes a lot of sense what shane is saying about the warranty safety. after reading all these post i am now happy again that my block is honed/bored. i was freaking out at first lol.

thanks for the info! everyone! now i can get back to getting this baby up and running.