so im burning oil on acceleration but thats the only time its burning according to my emission test results. i passed the high speed, but the idle test failed by like 3000ppm for hydrocarbons, and you can see a little blue smoke when accelerating. so this leads me to believe its the valve seals not the piston rings, correct? how hard is it to change out the seals? i know ill have to get a valve spring tool. but other than that, pretty straightforward?
That's true, but they also bolt on to 85-up blocks and that's the high compression combo. If it's a 20r head it will bolt up, but you will actually lose some compression so unless you want to swap out some early style domed pistons (and have a really high compression ratio and not be able to use pump gas) I'd advise against it. The 20r head has a cavity recessed into it to accept a domed piston and your '89 does not, it came with flat topped pistons and the bottom of the head is flat.
sorry to thread jack but how can i tell if the 20R head will fit on my block? my block looks like the old style one buts its got a single row timing chain... i got a 20r head sitting in my garage, if i can get some better performance bolting that sucka on i will, if its cheap and wont cost me an arm and a leg.
If you have domed pistons, you can just bolt it on. If you have flat topped pistons it's not going to help you performance without swapping domed pistons in. If you have a 85-up block and swap in domed pistons and a 20r head you will have VERY high compression, I am not sure about the numbers if you just swap a 20r head onto an old style 22r with domed pistons but with a 2mm higher deck height. I would guess it would be similar to stock compression, maybe higher, but not as high as the late style block that would yeild the 11.5:1, but really for most practical purposes that is way to high anyway IMO. I would be curious myself what the approximate compression ratio would be on an early style 22r with a 20r head. Also one way to tell a late style from a early style block is the lack of a knock sensor provision on an old block. It's there on the 85-up.
*typically* but not always valve stem seals will cause smoking at idle and for a short time after you hit the gas but then stop smoking as you continue. (IE leave a puff of smoke at a stop light but no trail leading away). usually if they continue to smoke as you drive either they're REALLY bad or it's rings and the smoke will be much worse at high rpm/load.
Id have to agree. It doesnt sound like valve seals. (At least the intake ones). Because the high manifold vaccume will pull oil thru the intake valve stem. But if you have to pass inspection, I guess start there. As for the hybrid stuff, I wouldnt try to do it. It takes alot of milling, a timing sprocket from LC, and some grinding. Its only really cheap and practical for pre 84 blocks.
