Muffleman Posted June 22, 2007 Share Posted June 22, 2007 I'm slightly down on one cylinder pressure, not a great deal but enough to make me consider getting it sorted early. Jamie recently dropped in a brand spanking new shortblock from Toyota and he says it's just flying, and we know these blocks take the power. So, do I have my block rebuilt with forged pistons etc or just whack in a new Toyota short block. I want to run upto 1.6bar and circa 600hp. And there's not much in it costwise Quote Link to comment Share on other sites More sharing options...
MrRalphMan Posted June 22, 2007 Share Posted June 22, 2007 I thought that the Toyota Short Block needed taking apart and cleaning up? Just me 2p's worth. Quote Link to comment Share on other sites More sharing options...
Alex Posted June 22, 2007 Share Posted June 22, 2007 The short block usually needs checking and cleaning as you don't want any metal fragments from the casting process in it. I would personally get a quote for both from someone like Mark or CW. Quote Link to comment Share on other sites More sharing options...
Muffleman Posted June 22, 2007 Author Share Posted June 22, 2007 Okay I'll make sure it is cleaned out if I go the new block route, but is that the best way to go ? Or rebuild mine ? I'll email CW for prices. Quote Link to comment Share on other sites More sharing options...
Alex Posted June 22, 2007 Share Posted June 22, 2007 Okay I'll make sure it is cleaned out if I go the new block route, but is that the best way to go ? Or rebuild mine ? I'll email CW for prices. I think it's worthwhile rebuilding the original as you will be running more power through it....but don't use cheap parts. I'd personally go for CP Pistons and Carillo H Rods...and end up with 86.5mm bores. CW doesn't like CP pistons but the yanks seem very happy with them. Quote Link to comment Share on other sites More sharing options...
Muffleman Posted June 22, 2007 Author Share Posted June 22, 2007 but don't use cheap parts. Never have done mate Have you had much experience of accralite pistons ? I have them in the MR2 but not yet put any serious stress through them. Quote Link to comment Share on other sites More sharing options...
Alex Posted June 22, 2007 Share Posted June 22, 2007 Never have done mate Have you had much experience of accralite pistons ? I have them in the MR2 but not yet put any serious stress through them. Heard of the company (used to advertise in proper racecar engineering magazines). UK based arn't they?? Might be worth a punt, I think CW tends to mention Omega for custom pistons... Quote Link to comment Share on other sites More sharing options...
Robbie Posted June 22, 2007 Share Posted June 22, 2007 I'm convinced the way to is buy an old engine, race it until/if it breaks and then replace it with another. Quote Link to comment Share on other sites More sharing options...
Stu Storm Posted June 22, 2007 Share Posted June 22, 2007 If it was me doing this then i would opt for a block that has done quite a lot of miles (over 100K) but is still in excellent condition as this way the block can take the stresses of more boost etc better due to haveing more heat cyles in it etc! The other way i did it was leave my block off my skyline out the back of my house for 12 months in weather conditions and then have it nicely cleaned up and new internals etc fitted and it is now a flying machine! These are called "seasoned" blocks in the trade.... HTH! Stu:d Quote Link to comment Share on other sites More sharing options...
Muffleman Posted June 22, 2007 Author Share Posted June 22, 2007 Heard of the company (used to advertise in proper racecar engineering magazines). UK based arn't they?? Might be worth a punt, I think CW tends to mention Omega for custom pistons... Yeah uk based, the guy that built the MR2 rallied 3SGTE engines and recommended them. Quote Link to comment Share on other sites More sharing options...
Alex Posted June 22, 2007 Share Posted June 22, 2007 I've heard of all this using seasoned blocks etc....but surely if it's gunna work its gunna work?? I think, Matt, you'll really need to decide once an inspection is done...the damage levels will determine if you can re-use the block at all... Quote Link to comment Share on other sites More sharing options...
JustGav Posted June 22, 2007 Share Posted June 22, 2007 I'm not sure about the logic of the heat cycles.... Surely it is a case of, the old block if it was going to have a stress fracture would have already had it...whereas the new block is a totally unknown one and there is no way of knowing if there is a stress fracturing in the casting. Although by putting more power in an old block you could in theory push it far enough to enlarge the minor stress fracture that was there... I personally believe it is down to luck really, after all none of us can see inside the casting to know how the metal has formed. As far as this thinking of leaving it out in the weather or peeing on it (as some F1 rumours go), I'm still never sure how truthful that is. How would letting a block oxidize help the strength of it.. Quote Link to comment Share on other sites More sharing options...
Muffleman Posted June 22, 2007 Author Share Posted June 22, 2007 I think, Matt, you'll really need to decide once an inspection is done...the damage levels will determine if you can re-use the block at all... I've emailed CW so will see what he says, I suspect there's no bore damage just a worn ring but we'll see. It's just one cylinder down about 30psi, the rest are absolutely fit and healthy. Quote Link to comment Share on other sites More sharing options...
gaz1 Posted June 22, 2007 Share Posted June 22, 2007 I'm not sure about the logic of the heat cycles.... Surely it is a case of, the old block if it was going to have a stress fracture would have already had it...whereas the new block is a totally unknown one and there is no way of knowing if there is a stress fracturing in the casting. Although by putting more power in an old block you could in theory push it far enough to enlarge the minor stress fracture that was there... I personally believe it is down to luck really, after all none of us can see inside the casting to know how the metal has formed. As far as this thinking of leaving it out in the weather or peeing on it (as some F1 rumours go), I'm still never sure how truthful that is. How would letting a block oxidize help the strength of it.. if you look at a lump of dog crap in you garden that was done today then look at one done last week the older more mature one would be harder:d that is about as techie as i can get:p Quote Link to comment Share on other sites More sharing options...
JustGav Posted June 22, 2007 Share Posted June 22, 2007 if you look at a lump of dog crap in you garden that was done today then look at one done last week the older more mature one would be harder:d that is about as techie as i can get:p I withdraw my previous statement, and agree with the above comment since it is techincally rather sound Quote Link to comment Share on other sites More sharing options...
AshBhp Posted June 22, 2007 Share Posted June 22, 2007 if you look at a lump of dog crap in you garden that was done today then look at one done last week the older more mature one would be harder:d that is about as techie as i can get:p :d I have heard some hardcore builders actually bury their engines in there back garden for a few years. :d But seriously cryogenics is the word Quote Link to comment Share on other sites More sharing options...
bromy Posted June 22, 2007 Share Posted June 22, 2007 The other way i did it was leave my block off my skyline out the back of my house for 12 months in weather conditions and then have it nicely cleaned up and new internals etc fitted and it is now a flying machine! These are called "seasoned" blocks in the trade.... HTH! Stu:d This does actually work in taking the stress out of the material, we used to machine cast iron beams probably 2 metres in length. The beams were cast in the Czech Republic and used to sit outside to 'weather' for months on a rotation system, if you tried to machine one not weathered the stresses in them was incredible they would to bend like bananas Quote Link to comment Share on other sites More sharing options...
Stu Storm Posted June 22, 2007 Share Posted June 22, 2007 hope my advice was of some help guys as i was told this info by a number of long standing engine builders who like to do things "old school" and credit where it is due they get great results! Stu Quote Link to comment Share on other sites More sharing options...
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