Iam doing a swap in a 89 crx hf auto, its gonna be a z6 head with probaby a y8 block...is that a good combo, the car is gonna get boost when its installed. Let me know what all iam going to need to the the engine swap and tranny, most likely its gonna be a si tranny. What computer do i need and wiring harness? Someone please help out.. Thanks

 

ok first off if i am correct the y8 head is like the big shit in sohc, so i would go with that head instead(but any vtec is better then none) now for the harness/ecu question it matter on what you want to do if you want to go obd1 or stay obd0 obd1 from what i've heard is a lot easier to have tuned correctly which is going to be a key part in your build so with that i cant help you ( me being o dohc guy) sorry but either way its going to be a good setup good luck and keep us posted

 

So.. z6 block and y8 head sounds good huh or what about the a6 block i heard it runs a high compression with a z6 head is that true? so i can keep the same harness and computer and the shit will run? this swap has to be dependable. All advise will be appreciated

 

a lot of people actually prefer the Z6 head to the Y8, if you look in the intake ports, the Z6 divider is completely vertical and the Y8's is slightly diagonal. the end result is better top end flow from the Z6 and slightly better fuel atomization (and hence, fuel economy) from the Y8 (at the expense of a few HP).

i ran a Z6 head on a Y7 block, but had A6 pistons in there too, and it was a pretty stout motor... so if u have the oppotunity, nab up some A6 pistons, throw them in the Y8 block, drop on your Z6 head, and get it tuned...

you will need wires run for the VTEC solenoid and the knock sensor, and depending on your cars stock IACV, you may need to change from a 3- to 2-wire IACV, but im not sure about the HFs. the computer will have to be a SOHC VTEC ecu, and you will most likely want some type of tuning, i believe the static c/r on the A6 pistons with the Z6 head is somewhere in the 11-11.5:1 range, which means your stock ECU will lean out pretty seriously.

GL with it man.

 

i mini me'd a y8 with the d15 block and it isnt worth the compression you get outta it. It's a big head ache. Stay in the gen and go with the z6, you'lll thank me latter.

 

aight well now iam just searching for parts......

 

and if ur goin boost likeu stated..ur not goin to want a6 pistons ..ull want to find some low comp pistons..perferably forged..

 

a y8 with a z6 head will be good for boost it will have a nice low compression....the main diff in the y8 head is the smaller quench area in the combustion chamber (less detonation). not really worth it since the z6 flows better, although the y8 intake mani is better... tha a6 pistons will be too high compression. stick with what you said at the top and youll do fine boosted...use your hf harness and wire in vtec and get a conversion harness and run obd1 for tuning purposes.

 

+1

good point, i forgot to mention that the Y8 IM is the best of all the D-series...

and dont worry about the different shapes of the coolant ports on the IM, use the Y8 IM gasket (with the circular coolant hole) and you will have no leaks.

 

Thanks alot guys...but deff iam going to put in some new eagle rods and maybe even some forged pistions dont kno yet... what do you guys think she'll run with the y8 block with eagle rods and the z6 head with a y8 intake manifold without boost on drag radials???