hey fellas
ive got some hardly used flat top pistons (about three months) out of my bros 307 chev v8, it was bored out 60 thou... can the 304 be bored out that far to fit them? i know the 304's bore is 101.6mm, what would be the chev motor's?
anyone know? cos i dont see why they should go to waste.... :roll:
al
Correct me if I am wrong, but once you bore the block 60thou, you wont ever be able to bore it again cause the cylinder walls are too thin.
Why dont you just get some 304 forgies and tak the block out 10 or 20thou???
Could get sleeves, to bring it back closer to original after a bore.
Also you would want a great block. I mean cast meticiously, if a water jacket were a few mm's out you would weaken the block that much that it would work better as a boat anchor/paper weight
yeh i thought about that, i just wasn't sure how far u could take them out saftely. it was just that my bro blew his moter and the block is screwed, he had to get a new one and its only bored out 30 thou, so the newish pistons are wasted, and aparently they where expensive...
thanks anyway
yeh i wouldnt feel safe taking the old plastic pig holden block out 60
then on top of that you would most likely need to run the chev rods, which would require machining work on the crank/rods
so its more than just dropping them in.....
i was planning on spending a bit of money on a v8, but i reckon ill wait till i can find an efi v8 with a five speed somewhere then start on that... also need to fin a nice car to put it in....
not from my experience...... decent performance bits have always been cheaper for a chev
there is a lot more support for the chev (more products + u can buy overseas)
im not building another big hp holden v8 again for the following reasons
1) 4 head bolt holes per cylinder as opposed to a SBC havin 5
2) weak mains tunnel compared to a chev, seems a lot of blocks have bad coreshift when being cast at the factory
3) no factory 4 bolt mains option (obviously can be converted but this adds to cost where it would be uncessary on the chev with careful block selection)
Quote:
Originally Posted by silver_ice
there is a lot more support for the chev (more products + u can buy overseas)
I assume you are talking about USA. At the current rate of exchange, its almost double price for parts, thats why Chev parts are more expensive. The aftermarket holden industry is massive, just look through any Street Commodores mag.
Quote:
Originally Posted by silver_ice
im not building another big hp holden v8 again for the following reasons
1) 4 head bolt holes per cylinder as opposed to a SBC havin 5
2) weak mains tunnel compared to a chev, seems a lot of blocks have bad coreshift when being cast at the factory
3) no factory 4 bolt mains option (obviously can be converted but this adds to cost where it would be uncessary on the chev with careful block selection)
1- Agree
2- Agree
3- Diagree -> Ok so its only one model but the VT 304 blocks are factory 4 bolt mains.
Also, COME racing does 4bolt main holden 5lt block for a touch more than than a crate block from Holden. Would be made better too.
Im aware that there is plenty of support for the holden v8 in Aus, no doubt about it, but, i dunno, it seems with some things (eg a decent set of rods) that there are 3x the amount of chevy options out there
also, a quick look throught vpwmailorder, i sitll maintain that if i were to build an identically spec'd motor one chev one holden the chev would still win in costs... but vpwmailorder do seem to have a bit of a mark up as well
the VT V8 does not have a factory 4 bolt main, just finished building one actually - i have to say tho, compared to earlier blocks, the VT blocks are have heaps more meat around the tunnel and definetly look much stronger
also, i understood that COME were working on a alloy 4 bolt holden block, didnt know it was released yet tho. anywhere i can find info on this??
cheers
Quote:
Originally Posted by silver_ice
the VT V8 does not have a factory 4 bolt main
My mates got a VT SS series 1, its got 4 bolt mains. No Kidding. It still the original factory engine too. Also, I am pretty sure the GTS came with 4BM as well.
Quote:
Originally Posted by silver_ice
also, i understood that COME were working on a alloy 4 bolt holden block, didnt know it was released yet tho. anywhere i can find info on this??
You are right, I am getting ahead of myself, the block isnt out yet. So sorry about that. more info though - www.comeracing.com
cheers
The Walkinshaw had 4 bolt mains.
Quite possibly the VN Group A as well???
On the VT blocks, maybe only the strokers came with the 4 bolt main?? I don't know just speculating like the rest of my post.
i have a 308 that has been bored 60tho and has flat tops but has dropped to head gaskets and a cam and lifter since it has been in y would this b
could it b the water jackets 4 the gaskets and what would stuff the cam and lifter???the lifter put the rod through the rocker and the cam and lifter were both rounded off on number 2 in-let....my machanic seems to think it has some thing to do with the block and to much compression with the flat top pistons do u think this might b??????????
Bit of a change in plans now...
when the bloke up in NSW took the left head off, he said the block was cracked etc, so he didnt take off the other head.
got the motor down to tassy and took it to get rebuilt with a new block, crank, con rods and pistons and found when the right head had been taken off, the place that tuned the carbie had dropped a screw into the manifold and it had worked its way down into the cylinder over time and it cracked the piston, which then put a huge hole into the block. so its all pretty much ruined
ive got some pics, ill upload them tonight
