[RESOLVED] What year heads do I have?

[Clutch GSX]

I supposedly have two 1G heads but they are different. I need to know what the differences are for a 90-91 turbo head, 92-94 turbo head and 90-94 non turbo head. Or at least which two heads I have. So far I can see that my second head has longer cam cap bolts and visually the heads are very slightly different. There is an extra bolt hole on the thermostat side of the second head. The first head says 2.0L on it and the second head says 6G. I can take pics if it helps.

Thanks

 

[Jeff99GS]

Yeah pictures would help for sure. It's hard to identify something without seeing it.

As far as I know the 1g Turbo and NT heads are the SAME except for the intake Camshaft and a couple of small things. Like the Turbo Oil feed port is plugged on the NT head obviously.

 

[Purevil]

The 1990 heads have smaller coolant passages. Other that that, all 1g heads are nearly identical, the n/t's have different cams and turbo cams vary slightly year to year. There is a plug where the oil line attaches on n/t heads as previously mentioned. The 1990-1992.5 heads are 6 bolt and use 12mm head bolts. The 1992.5-1994 heads are 7 bolt and use 11mm head bolts. The heads themselves are identical and use identical valves, springs, etc... All the ports are the same and the performance figures will be the same from head to head.

 

[turboglenn]

well, as i recently found out "early 90" heads ahve an oil distribution block with a pressure relief vlave in it. look at my thread under the short-block section called "other options for excessive oil pressure" Amember called pneumo posted some good pics and info on the early 90 oil block. other than that the differences are as noted above.

 

[nuclearr]

Are you sure its a 2.0 there is a 1.6 1.8 and 2.0 the for the most part look nearly identical. They are all made from the same core but have smaller combustion chambers. If your heads still have the marks from the old head gasket you can take and lay a head gasket on it and the piston ring on the gasket will not match up.

 

[Clutch GSX]

Here are some pics showing the differences. The black one is the old one and the unpainted is new. The bolts are the cam cap bolts and as you can see the newer ones are longer. Can I use the shorter ones on the new head? Which head is better and what heads are they?

Thanks guys.

PS in the 2nd pic the black head is the one on bottom

 

[turboglenn]

Wow..and niether of those area early 90 style by the oil dist. block. the black one would be 92.4 and newer i believe, and he other one ??? looks like a 4g family head, but could be any variation. I had a weird head, turned out it was from a pre-mivec EVO 1.6liter car (too bad the cam journals were shot, it's got one hell of a port job) i just hope it don't cost much over the estimate to fix. )

 

[Clutch GSX]

Why is this marked resolved?? I still do not know what kind of head I have or if it's better or worse than my original one. I also need to know if I can use my shorter cam cap bolts on the new, unpainted head.

 

[thilaksharma]

hmm
the top black is a big port 1g or vr4 head
the below should be a 2g or evo head really unsure , please do let us know whether is has a big port or small port

may check my thread for some info
http://www.dsmtuners.com/forums/cyl...s-intake-turbos-clear-out-misconceptions.html

 

[Clutch GSX]

Both heads have been ported so pay no attention to the port sizes. I still have no idea what kind of head I have.

 

[Purevil]

It could also be a Hyundai head.