Factory Suzuki Every with the 660 turbocharged engine. Last owner let it get hot, thought he just blew the headgasket. Turns out the head is warped too. Need help from those who have experience with these things... if we machine the head to true it up, have the deck machines, reinstall with fresh headgasket...is this just a patch? Will the tighter tolerances on the head increase the compression ratio enough that it is an issue with the boosted engine (detonation requiring a retune?) I want to make sure we fix this right, as it turns out the last patch didn't last. Any and all help and suggestions are appreciated.
You bought this one from the fella in Squamish right? How much do you have to machine the head? If it's too much, you'll raise the compression. Increased compression can lead to detonation. You might need to go with a copper head gasket to space it back out a bit to regain compression....
Hey Jason, yeah its me... you and I chatted on here before. Murphy's law... buy somehing site unseen and it will likely give you a few surprises! The engine is apart, wondering how far we should dig into it?!
you can always back the timing off a few degrees to reduce detonation, but you will obviously lose a bit of power..maybe not much tho with a higher CR
Wow, I had my suspicions about that when I talked to the owner. This is the second head gasket that let go on him and I don't think he checked the head either time .... Pretty crumby. Be careful with decking the head, you should CC the combustion chambers first and try to maintain the stock volume by perhaps enlarging the chambers a bit. As Fupa says you can back off the timing a bit, however, this only helps a bit if you get the compression up there. While you have the head off, perhaps change the valve stem seals and do a bit of port polishing too, seems to help quite a bit. Good Luck!
Any experience with the turbo charged engine? Is it the same as the naturally aspirated, just different manifold and addition of the turbo? Are these in fact the same as the engines used in the Suzuki built Geo's, Sprint's, and Firefly's? If so, then parts should be available used at various wreckers? Jason, what engine does your Suzuki/VW have?
I've no experience with the turbocharged F6A. I think that you've got EFI instead of the carb that I have and I'd suspect that you'll have a bit lower compression than the normally aspirated F6A that I have in mine. These seem to be a different engine family than that of the Geo's and such also. There's gasket sets and such available on Ebay right now so you should be able to get those at least.
Don't sweat the extra compression, it will only make the engine more efficient in the long run. De-burr the comb. chambers to remove any potential hotspots but don't bother to open them up. The small bores of the little lump are very det. resistant and you can get away with quite a bit. The main reason for head warping for something so small would definately be the overheating. It's very rare to have a seasoned part that has been machined once already to warp again. Pay paticular attention to the head bolts and the torque values and sequence. There is no reason why a motor this physicaly small can't cope with the stock boost and load limits. Jon.