engine bore and o-ring question

[BluemeanieTSi]

can a 4g63 block be bored clear to .060 and still have enough room to have the block o-ringed?

 

[BluemeanieTSi]

wasn't sure if this was something to put in extreme tech or not....

 

[BluemeanieTSi]

actually here's a question...from wha ti'm reading it seems to be better to oring the head instead.

oring block or head?

 

[1fast97gsx]

why would you bore to + .060???

 

[BluemeanieTSi]

cuz it's an option with weisco pistons

 

[1fast97gsx]

cuz it's an option with weisco pistons

I know that ... but why not just go with .020 or if you need to then + .040?? The bigger you go the more you are weakening the block.

 

[BluemeanieTSi]

I know that ... but why not just go with .020 or if you need to then + .040?? The bigger you go the more you are weakening the block.

blocks are thick as hell to begin with and .060 is less than 1/16th inch i think

 

[herostar]

.060 over is 1.5mm over

Anyways, I would go the minimum amount overbore you can so that down the road if you need to re-bore the engine there is still room. Yes the blocks are thick, but that's for a reason. Think about it this way. If you went .060 over right away what would you do if you needed to re-bore your block again? There wouldn't be any room to go larger (and nobody that I know of makes a piston for that) The extra displacement you are adding by overboring your engine will not produce any substantial power increase (maybe 5hp)

 

[Defiant]

Maximum bore for a DSM block is .040. It's all but pointless if you don't have gouged bores, and at that, the blocks are so plentiful and cheap that you're better-off to grab another from the pile than to have to overbore it. It's not like a V-8: you're not going to gain enough displacement from boring to make it worthwhile.

O-rings go in the block, not in the aluminum head. They're seldom used on DSM blocks, because they're not needed.

And please do not bump your posts.

 

[BluemeanieTSi]

wasn't bumping my posts

if something happened to that block and it needed rebored for some reason i'd scrap it.

as for the oringing if you actually look it up you'll find that guys are oringing the head and not the block.

dsmotorsports will oring their race heads for you at a price, buschur orings the heads after experimenting with oringing blocks and heads/blocks combinations. if the maximum was .040 they wouldnt' sell .050 and .060 pistons.....or no one would buy them.

they are more commonly used in dsm applications now with large turbos and high boost you'll find they use the stock gasket/oringed head combo or the copper gasket oringed head combo

 

[Mirage2LTurbo]

If you want to bore for displacement, sell your DSM and buy a Chevy.

 

[myblack98gst]

there is no reason to bore that large, this is the point you are missing.. if you want to pick up displaement so badly then do a stroker motor.

and there is really no reason to o-ring the block a mitsu MLS or HKS MLS and ARP's will handle just about anything you throw at them

 

[BluemeanieTSi]

ARP's will handle just about anything you throw at them

no they don't....have you read up on it much?

 

[BluemeanieTSi]

If you want to bore for displacement, sell your DSM and buy a Chevy.

cute.

 

[herostar]

no they don't....have you read up on it much?

I'd like to see proof of this.

Not to flame, but I've seen TONS of cars making well over 600whp using a MLS headgasket and ARP's. Hell, mine makes over 400 and it's working fine. O-ringing really isn't something you need to do for a dsm, otherwise you'd see more people doing it. I bet there are no more than 500 of the 30,000+ members on these forums that have o-ringed engines.

 

[BluemeanieTSi]

I'd like to see proof of this.

Not to flame, but I've seen TONS of cars making well over 600whp using a MLS headgasket and ARP's. Hell, mine makes over 400 and it's working fine. O-ringing really isn't something you need to do for a dsm, otherwise you'd see more people doing it. I bet there are no more than 500 of the 30,000+ members on these forums that have o-ringed engines.

there are more poeple doing it they're just not posting on forums about it because most of them have grown tired of message boards.

the guys i talk to have been building dsms for 10+ years and were having head gasket problems with large turbos and high boost that were solved with oringing. it's not a difficult concept to understand. www.dsmotorsport.com offers it now on their race heads like i said before. look i'm not here to argue i'm here to get my questions answered but looks like i'm answering them myself. do a google search for dsm head oring

 

[NDgsx]

People with headgasket problems usually actually had a problem with their surface not being smooth enough for proper MLS sealing.
The slightly larger bore is not enough to make a significant change in power, however you can use larger bore sizes to unshroud 1mm over valves. In that case you would inderectly pick up power due to the bore size.

 

[1fast97gsx]

there are more poeple doing it they're just not posting on forums about it because most of them have grown tired of message boards.

the guys i talk to have been building dsms for 10+ years and were having head gasket problems with large turbos and high boost that were solved with oringing.

Then why don't you just ask them for help and not us. The best thing for you is to put the wrench down and leave the car alone ... if you absolutely must build the engine for god knows what reason then go with the smallest size increase possible. If you are asking these questions you don't need anything oringed ... just deck the head and block, get a set of arps and a good headgasket.

 

[BluemeanieTSi]

Then why don't you just ask them for help and not us. The best thing for you is to put the wrench down and leave the car alone ... if you absolutely must build the engine for god knows what reason then go with the smallest size increase possible. If you are asking these questions you don't need anything oringed ... just deck the head and block, get a set of arps and a good headgasket.

you're absolutly right, it was pointless to ask this question here. why MUST i build an engine? because my valve stems put holes in my pistons and i need something to support an fp3065 as a daily driver making 500-600whp. block/deck surfacing has nothigng to do with whether or not to oring, the 500-600hp cars everyone talks about weren't using the turbos that are out today, they were doing it with less internal pressure and more of a supporting mods thing, people going with larger turbos have been running into head gasket problems with these and the starion motors for a couple years. i never meant to be an ass but honestly we're not talking about making modest power on a daily driver we're talking about making a drag car with the intention of ONLY having it state inspected for possible weekend use. if i wanted to play it safe i wouldnt' bother with a 3065

the only good responce so far was the valve answer in which yes, it would help with the 2mm oversized valves woulnd't it

 

[herostar]

I would just go with .040 over to be safe, because you know that that can be o-ringed.

Also, your 3065 flows maybe 5lb/min more (being totally efficient) than my turbo, but I'm not having any headgasket problems flowing that much air even on a stroker motor. Just make sure that whoever does your o-ringing and machining on your head and block is a competent shop that does good work, and I think you'll be just fine

 

[BluemeanieTSi]

I would just go with .040 over to be safe, because you know that that can be o-ringed.

Also, your 3065 flows maybe 5lb/min more (being totally efficient) than my turbo, but I'm not having any headgasket problems flowing that much air even on a stroker motor. Just make sure that whoever does your o-ringing and machining on your head and block is a competent shop that does good work, and I think you'll be just fine

that'st the answer i was looking for...now the only other thing is 1/2 the poeple i've seen oring the head some say oring the block i think i'll try the head first as heads are plentiful

 

[Bastard1g]

You could always ship your turbo to me and I could give it a try for a few years to see if I could blow my motor.

 

[BluemeanieTSi]

You could always ship your turbo to me and I could give it a try for a few years to see if I could blow my motor.

sounds like a plan