94 vs 95 ka24e heads

[jhhaz]

Been told a 94 ka24e head won't fit a 95? Why not?

[-RJ-]

what?

use google

[jhhaz]

I'll type it slowly - what are the differences between a 1994 KA24E cylinder head and a 1995 KA24E cylinder head? Why are they not interchangable?

[seang]

The only differences that I am aware of are the obd1 and obd2 years.

I think obd2 ports might be enlarged a little bit, but that is for the sidefeed injectors or something. Also, I read somewhere that the bigger ports flow a little less for some reason: I have seen no flow charts to prove anything, so, sorry. Do not quote me on this one.

People have said that some 95's are still obd1. This was a transition year, so maybe there are some parts from both on these ones. Beats me.

Obd2 distributors are different than obd1 in that they have an internal coil.

I don't know if the front covers are the same. This would be the only thing I can think of to be crucial. To be honest, I've never heard that 94 and 95 heads couldn't be interchanged.

I wish I could tell you some more definitive things. Google "obd1 vs obd2 ka24e", or some variation of that. Maybe some KA guru that isn't busy will troll by and see this. Hard to say.

[jonas92]

i may be mistaken but i didnt think there were 94 or 95 single cams?

[Rev_D21]

The trucks had single cams up till 97. Sean is correct that some 95's were ODBI still. The switch over happened sometime after 2/95. Most of the mechanicals remained the same while most of the emission system was updated. You can interchange an early 95 KAE head with a 94 KAE head and not have to change much else with it.

[jhhaz]

Thanks for the info from everybody! I didn't use the old head from the engine or the "free" '94 head my son-in-law had. Decided to order a rebuilt one rather than wait on the machine shop to fix everything. I have heard that there were differences but couldn't find anything about what the differences actually were. The 94 looked just like the head I removed. Bolt holes matched when set on the block, etc. I didn't check port size but measured valves, combustion chamber volume, cam lift - pretty much everything but the ports! The truck does have a coil external the distributor though. This is my first time rebuilding a KA24 and I had to get the '95. I hate to buy parts when they ask "what month?". I say why. Model change. Whats the difference? I dont' know. Well lets find out before we peel out benjamins! Looking forward to putting this together again. Again - thanks all!