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"other' car brand engine bits have been interchangeable for performance gains in the past, such as swapping heads between models or even capacities to get better compression or flow characteristics.

One example could be fitting 302C heads on 351C and getting a compression boost resulting in better power delivery, few more miles an hour in each gear.

Another would be the later bigger (by 2mm ) valved EA81 heads on pre 84 EA81's.

170 ci head on a 250ci Falcon pre cross flow stuff also supposedly raised performance.

Can this be done with EJ components like an EJ16 head on an EJ18 or 20 , or the other way around like EJ20 /22 SOHC heads open up an EJ16/18?

Manifolds and trottle bodies?

if EJ,s are like most rice burners the 20 head should fit 22 motor giving better compression but the goes for any engine family i had a F head (3.9L) on my landcruiser 2F (4.2L)

throttle bodies dont really do much power wise unless you,ve done excessive mods but im guessing a high rise manifold would see good power gains

It gets tricky with EJ's when you
get different heads and blocks,
without having the VIN of both
cars the parts came off and EJ's
can be bad for different Gaskets.

especialy with JDM stuff!

you can put ej22 heads onto the sohc ej25's apparently the high compression 2.5 goes very well

hmmm L series ej25+22 heads= wheres guyph :P we,ll test this theory

HAHA this is one i can answer =P

they are pretty all interchangable. The frankenmotors that americans make are mostly 25 blocks, pistons whatnot, with 20 turbo heads to get the air flow.

mud_king91 wrote:we,ll test this theory

It's not theory, it's practise! Check out USMB and search "frankienmotor" or something of the like. Apparently a very easy performance upgrade.

Generally the EJ manifolds are interchangeable, but with this the common practise is to only move the intake manifold with the matching ECU, otherwise you could be fabricating brackets to fit the ECU's original sensors to the new manifold. That and I'm not sure if there's huge performance gains in a manifold swap...

Cheers

Bennie

i know the RB30 to 25 twin cam head conversion gives good power atleast enough to make it worth the time and money anyway

mud_king91 wrote:i know the RB30 to 25 twin cam head conversion gives good power atleast enough to make it worth the time and money anyway

That's basically the same for the Ej25 block with EJ22 heads. But usually most will swap the block for a known good one - no wiring to change. But if it's a conversion into an L or something of the like then they'll pick the ECU, wiring to go with the heads and the EJ25 block.

Cheers

Bennie

Confirm the heads are pre or post MY 99 heads
and Inlet manifold as they have different
bolt patterns.

ok im confused... so for instance i put a ej25 sohc into subius clay ( i know iv already named my next project sad) do i use ej 22 ecu, wiring and manifold with 22 heads or do i use the 25 gear and just swap the heads ?

hmmm, so EJ16 heads don't feature anywhere here then ??

I looked at EJ18 heads onto an EJ22 block. IIRC the EJ18 inlet valves were 1-2mm smaller in diameter than the EJ22 ones, exhaust valves were the same, ports looked the same and the chamber volume was suitably smaller on the 18. Probably would have worked, but I didn't have the means to experiment with it at the time.

Have a play with the 16 bits - high compression 2.0L turbo LPG Vortex?

Dane.

There was an excel spreadsheet floating around on USMB with specs of different engines for calculating displacements, compression ratios etc of frankenmotors. Will try and find it later on.

GOD wrote:I looked at EJ18 heads onto an EJ22 block. IIRC the EJ18 inlet valves were 1-2mm smaller in diameter than the EJ22 ones, exhaust valves were the same, ports looked the same and the chamber volume was suitably smaller on the 18. Probably would have worked, but I didn't have the means to experiment with it at the time.

Have a play with the 16 bits - high compression 2.0L turbo LPG Vortex?

Dane.

it should of what you explained there is similar to the the tickford vs standard falcon head... amazing how many heads are compatible with engines isnt it i think its more amazing the fact that a head change takes me an hour or 2 and look at the power gains

an hour or two ? Not a Subaru time, and that is about how long it takes to do the inlet nuts/studs on 'newer' Falco sixes !

ok things are getting newer and complicated firstly i was talking early falcon and secondly iv managed to rush a rebuild on a buick V6 it took me 10 hours... rattle gun