SOHC to DOHC Head Swap

[dutman94hb]

Well ive got a 94 Hardbody with the ka24e motor but i want to swap it for the ka24de head. First is it possible and Second what all would i need (besides the head) to complete this swap?

ANY INFO WILL BE HELPFUL AND APPRECIATED

[deviousKA]

Yes it is possible, you have a few options. First of all i would say it is in your best interest to find and use a 98+frontier cylinder head. This, like an altima head, requires much less extension of the lower sohc cover to fit the de head. This also allows you to use either a 240sx de intake or truck de intake (basically identical to sohc truck intake). A truck dohc ka block is pretty much a truck sohc block, only minor difference being where the front cover of the head mounts. Im 95% sure you could even use a truck dohc lower timing chain cover on a sohc truck or 240sx block which would make everything a bolt up affair. Truck de use both sohc type oil pump and distributor.

You could always use a 240sx cylinder head, not as easy as far as fitment on front cover. Or an altima head, which requires custom intake manifold and water neck that comes out on exhaust side for radiator, but has the front cover characteristics of the truck de.

If you want to retain your oem ecu, harness, sensors, and all locations, use the truck dohc intake with throttle body mounted maf.

btw. you will want to find a frontier de exhaust manifold as well, this should bolt up to your stock y-pipe correct. Exhaust manifolds between 240sxdohc/truckdohc/altimadohc are interchangable.

[dutman94hb]

Thanks alot Devious that really helps alot in makin my decision on what to go with. But i have one more question what performance gains will i see by doin this swap?

[deviousKA]

The compression ratio will change from 8.6:1 to 11.1:1, that is all. It is the same as using ka24e pistons in a ka24de engine, only effective change is the dish volume of the piston. It is much easier to just swap sohc pistons in a complete de engine, that is, if you have a complete de engine. Only if your poor/bored/or interested in taking advantage of other possibilities should you consider the ka24e to de headswap. In your case its much easier to do this swap (vs 240sx), if you find the rwd ka24de frontier engine or parts needed. Who knows you might save a little money from not buying the frontier block? but I kind of doubt it.

As far as the benefit from the higher compression, look around.

[hamsterball]

geeez... i didn't know a '98 truck head would work like that...

I have a valve tap problem (don't feel like spending the $300+ on new lifters and $180 for a possibly damaged camshaft), so i think i'll look into this!!

hopefully i can find one

[InsanityInc]

also, you'll gain VE advantages from the superior cam setup, and less valvetrain loss, considering it's a fully mechanical valvetrain in the DOHC head.
Modified by InsanityInc at 3:36 AM 11/3/2004

[deviousKA]

I sell ka24e solid lifter conversion if your interested, $220.

[dutman94hb]

will the stock ignition retart enough to handle 11 to 1??? cooling problems with 93 octane?

[InsanityInc]

11.6:1 should be fine with 93.

[sleepyRPS13]

sorry for high jackness...devious do you have any sound files of your car? just want to hear how a 2.5 itb ka sounds like.

[Kansei240sx]

I wanna hear that beast as well, It looks sharp!

[deviousKA]

Sorry guys i dont have any clips, next spring.