Poly Engine what was good/bad about it and why is the LA better?
Before a bunch of people jump on the poly-headed LA train like running LA heads on a magnum (without the head oil galleries), the Hinkle engine really isn't a good example, and the descriptions online and in magazines about this engine are b.s. That engine had to only survive a few pulls up to 6,500 rpm on a dyno, and the builders had plenty of money and equipment necessary to compete in an AMSOIL challenge regardless of if the engine survived or not. Here's a photo of this engine bursting into flames during that test (supposedly an oil gasket leak, but the engine's condition afterwards isn't verified):
The description you quoted and that are in the competition results says installing oil drain-backs and pushrod clearancing is all that's needed to fit A318 heads on an LA. B.s. How about the four large cooling ports in the A318 heads that dump into the LA valley? The LA head gasket sticks up past the deck and covers these, and rumor has it the gasket will allow the engine to run for a very short time before the gasket bulges and coolant dumps into the valley. If all the Hinkles did were oil drain-backs and pushrod clearancing, they built a milkshake oil machine that lasted long enough for a few dyno pulls before the thing caught fire. Run that engine for more than 30 minutes and the crankcase would have filled with coolant.
The proof is in the pudding: if all it takes is oil drain-backs and pushrod clearancing, we'd have poly-headed LAs all over the place just like we have LA-headed magnums (without the head oil galleries). This was the Hinkle's first build of an A318. There's a reason why even Gary Pavlovich hasn't retrofitted A318 heads on an LA block, and he's been building A318s since the 60's.
Before a bunch of people jump on the poly-headed LA train like running LA heads on a magnum (without the head oil galleries), the Hinkle engine really isn't a good example, and the descriptions online and in magazines about this engine are b.s. That engine had to only survive a few pulls up to 6,500 rpm on a dyno, and the builders had plenty of money and equipment necessary to compete in an AMSOIL challenge regardless of if the engine survived or not. Here's a photo of this engine bursting into flames during that test (supposedly an oil gasket leak, but the engine's condition afterwards isn't verified):
The description you quoted and that are in the competition results says installing oil drain-backs and pushrod clearancing is all that's needed to fit A318 heads on an LA. B.s. How about the four large cooling ports in the A318 heads that dump into the LA valley? The LA head gasket sticks up past the deck and covers these, and rumor has it the gasket will allow the engine to run for a very short time before the gasket bulges and coolant dumps into the valley. If all the Hinkles did were oil drain-backs and pushrod clearancing, they built a milkshake oil machine that lasted long enough for a few dyno pulls before the thing caught fire. Run that engine for more than 30 minutes and the crankcase would have filled with coolant.
The proof is in the pudding: if all it takes is oil drain-backs and pushrod clearancing, we'd have poly-headed LAs all over the place just like we have LA-headed magnums (without the head oil galleries). This was the Hinkle's first build of an A318. There's a reason why even Gary Pavlovich hasn't retrofitted A318 heads on an LA block, and he's been building A318s since the 60's.
