hYbRid_Eg6

iTrader: (2)

ok I have a b series (gsr) block which is sleeved, that is bored out to 85.5mm, I wanted to boost it, anyone have the same bore that is boosted? And anyone have problems with the head gasket not sealing?

king06

iTrader: (1)

Mine was at 85, had it for three months and blew the head gasket, but it was most likely due to me over heating the car.

In my opinion you can run it, but it's going to be really low boost level because no tuner is going to wanna tune it.

Re-sleeve it, sell it or do stock sleeves.

pettyboy69

iTrader: (2)

its a toss up personally i would just get a stock bore block and build that but hell if you already have the motor i can understand someone using what they have but stock 81mm bore forged internals are way easier and cheaper to buy then 85.5mm bore pistons.

I would sell that block to someone looking for an all motor build cuz when it comes to NA there is no replacement for displacement lucky for us turbo guys we dont have to worry bout cubic inches lol

CerealKiller

As stated before, you're better off selling it. The biggest bore I would go is 84.5mm, but that's just me. Some do boost 85.mm.

cjordan

iTrader: (1)

i also agree anything over 84.5mm is to big for boost. my old B16 was 84.5 and it ran great never had any heat issues really, my current set up has a 84mm GSR bottom end...

hYbRid_Eg6

iTrader: (2)

well I have a stock gsr motor in my DD, I got this block with eagle rods and a type r crank for a great price, I was thinking that I can boost the 85 block cause it was sleeved, I keep getting mix signals from everyone I talk to, yes it can work just torque the head down 5 more pounds then you would be fine, then people say thats too much, gaskets will blow, my goals are to make 350-400 on pump 15-18psi (just guessing) on a gt3076r.

hYbRid_Eg6

iTrader: (2)

how long would the head gasket last at 15-18 psi at this bore?

bettsbanger

probably wouldn't last too long. my tuner won't touch a boosted gsr over 84mm. i'd suggest just sellin it to an NA guy and get yourself a freshly sleeved 83-84mm block

byrne_06

Boost it. copper spray the hell out of the headgasket and give her. If she blows a head gasket then just sell the block. I made 380 whp and 265 ft/lbs on 17psi on e85 on a
b18c1 with ge rods, cp pistons in stock sleeves, i coulda made more but my exhuast was only 2.5in same with my downpipe. Its all trial and error. If it breaks, rebuild and do it all over again.

Turbo-LS

iTrader: (4)

its not that the block wont handle the boost its that when your at that large of a bore the material between the cylinders is very thin and you have a very high potential for blowing out headgaskets as there wont be much there to seal bwteen the cylinders and its probably to thin to do orings but maye you can get away with that and it will seal up properly.

you can always run low boost 20 or less psi. if your not trying to make a drag car here then i dont see you haveing a huge issue. you can also buy new sleeves for a couple hundred bucks and get the installed. the most expensive part of the sleeve job is the machine work and thats already done

hYbRid_Eg6

iTrader: (2)

orings?... hows does that work?.... but I'm really not tryin to make a drag car here, only really want to boost around 15-20 psi and no more! i got this block really really cheap, just using what i got, you know what i mean, the only decision i have to make which pistions to buy, boost or N/A. Maybe i will just have to save money to buy a different set of rods and pistions and boost my stock gsr and use this block for a crazy N/A motor for back up?

hYbRid_Eg6

iTrader: (2)

ok I really want to see boost! I dont think the head gasket is going to be a issue, it looks like there is enough material by lookin in between the clyinders? heres a pic, what do you guys think?

Turbo-LS

iTrader: (4)

it might not be a problem but it could be one as well. i could be wrong but from the looks of the pics that doesnt seem 85.5mm. have you had a dialbore gauge on it to measure? someone correct me if im wrong.

hYbRid_Eg6

iTrader: (2)

well i just got it back from the machine shop, i told them to bore it out to 85.5mm, why does it wierd? looks smaller than 85.5mm?

LowBudgetBEe

did u give them a 85.5mm piston. usually they wont bore without the piston. it doesnt look 85.5mm

vtechjunkie

iTrader: (2)

How can you guys tell what bore that looks like? There isn't any reference to gauge from in that pic. Dude just sell the block and get something a bit smaller. Or trade. Whatever you want. Much less headache. With selling it you can at least get some of your money out of it. Rather than ruining the pistons among other things, thus having to start completely over.

hYbRid_Eg6

iTrader: (2)

well no, i bought this block from a friend, he drop a valve and messed up cylinder wall pretty bad, he told me it was already at 85, so i took it to the machine shop to see if was fixable and they called me a week later, and said they didnt have to bore it out to 86mm they just went .020 over from what it was.

hYbRid_Eg6

iTrader: (2)

ok i just measured it on my dial caliper and its at 3.358in, caliper could be off, thats close to 3.366in which is 85.5mm right?

boosted94gsr

3.358in converts to 85.2932mm and 3.366in = 85.4964mm

hYbRid_Eg6

iTrader: (2)

so that means its it closer to 85.5mm? machine shop left room to do final bore when i get pistons in right? its .0008 off to get to 3.366, but anyways I would sell it but I live in ALASKA! people here are broke!! haha