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Chasing 1000hp, where to get parts for a head rebuild.
Chasing 1000hp, where to get parts for a head rebuild.
Many moons, many, drinks, many substances ago I had the engine rebuilt for the memory I have left the head remained pretty much stock, just match ported manifolds and a 2mm copper head gasket.... Not crackin the engine open untill the car is going as I'm not takin any more steps backwards in gettin this biatch movin.
I guess I'm just after peoples experiences with head rebuilds, what's broken when it has, what has worked with a big turbo disregarding drivability running hi boost.
I guess I'm just after peoples experiences with head rebuilds, what's broken when it has, what has worked with a big turbo disregarding drivability running hi boost.
- tassuperkart
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- Location: Southern Tasmania
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Big issue with these heads is softening of the alloy over a long time resulting in repeatedly blowing HG's or in the case of a solid, pressurising and aeration the cooling system and annoying overheating.
Next is cracking between the spark plug holes and the exhaust valves. happens with plenty of high boost engines.
Another horror is turbo manifold studs pulling out of the head due to hanging the entire weight of turbo/dump and exhaust show straight off the manifold with no flex joints, zorst hanger brackets or the turbo stay being removed which is the case on almost all of them!!!!
Other than that, usually plain sailing.
L8r
Oracle
Next is cracking between the spark plug holes and the exhaust valves. happens with plenty of high boost engines.
Another horror is turbo manifold studs pulling out of the head due to hanging the entire weight of turbo/dump and exhaust show straight off the manifold with no flex joints, zorst hanger brackets or the turbo stay being removed which is the case on almost all of them!!!!
Other than that, usually plain sailing.
L8r
Oracle
Forcd4 wrote:Oh fuk no dude it's you a again, the oracle.
- tassuperkart
- Administrator
- Posts: 5578
- Joined: Wed Jul 05, 2006 8:39 pm
- Location: Southern Tasmania
- Contact:
tassuperkart wrote:Big issue with these heads is softening of the alloy over a long time resulting in repeatedly blowing HG's or in the case of a solid, pressurising and aeration the cooling system and annoying overheating.
Next is cracking between the spark plug holes and the exhaust valves. happens with plenty of high boost engines.
Another horror is turbo manifold studs pulling out of the head due to hanging the entire weight of turbo/dump and exhaust show straight off the manifold with no flex joints, zorst hanger brackets or the turbo stay being removed which is the case on almost all of them!!!!
Other than that, usually plain sailing.
L8r
So any suggestions on what parts should be upgraded? I'm bracing the turbo to support its weight, copper gasket has held...... So far so good. The cracking between sparkles would shit me.
Oracle
" Friends may come and go but 200lbs is always 200lbs " - Henry Rolland -
Assemble the head with the heavier valve springs (search for details on that) - new set of of valve stem seals, and ensure your valves are seated properly, ensure the head and block are straight and even. Then assemble engine/head.
Then get it all tuned and running, take it down the strip and see how it goes.
Once you get to that stage, then you should look for spare head to start your flow developments.
I think you may find that head will become a less priority once you start running.
History says in the past that people that have drag raced these cars have ran REALLY quick times with standard heads. In doing this they have consumed gearboxes and CV's much more regularly than head issues - other than blowing gaskets from incorrect tunes. (refer above - get it tuned correctly)
If you get to the point of pushing the standard heads flow capacity, I will be suitable impressed because I think other issues may jump up at you first.
Regards,
Darren.
Then get it all tuned and running, take it down the strip and see how it goes.
Once you get to that stage, then you should look for spare head to start your flow developments.
I think you may find that head will become a less priority once you start running.
History says in the past that people that have drag raced these cars have ran REALLY quick times with standard heads. In doing this they have consumed gearboxes and CV's much more regularly than head issues - other than blowing gaskets from incorrect tunes. (refer above - get it tuned correctly)
If you get to the point of pushing the standard heads flow capacity, I will be suitable impressed because I think other issues may jump up at you first.
Regards,
Darren.
Race it.
I've minced at least 6 boxes thus far but after the n13 gearset with 4.11's I haven't had a drama... Even at 180 odd killa twats, without slicks but that's when I see problems arising, or the fact I still gotta find some midget to run it, if I'm after serious numbers I've stripped weight off it if i drive it I may as well have left the interior in. Haven't blown one gasket with the copper one still holding.... I want a few good runs first, but I'm quietly looking forward to breaking shit... It's a guy thing i think.
" Friends may come and go but 200lbs is always 200lbs " - Henry Rolland -