Rev3 Head ..

[Bibbs]

Will one fit on a rev2 .. and whould to be any good?

[Dame]

I believe that this is possible, since AFAIK the engine blocks are the same for both generations of engine. If you changed all of the differing parts i.e. replaced AFM with map sensor, swapped injectors etc. you should end up with an engine identicle to that found in a Rev 3. I've thought about doing this myself. There is a list of the changes made to the engine somewhere on the web, worth loking at.

I suppose it really depends on what parts are included with the head ie the injectors, and you would need the induction assemby and the ECU from a rev3 too not sure if the wiring loom is the same either?

I fear cost may be prohibitive, it might be cheaper and easier to perform a simple (he he) engine change job. Guess you'll be looking around for a written off low milage Rev 3 Turbo then :)

[dawesy]

i know that an st-205 head fits an st-185 block so would think same for the 2. you do need the manifolds (inlet and exhaust) map sensor and ecu+loom as i believe the rev 2 is afm?.

as for gains its the head etc that made the power difference between rev 2 and 3 so if you can find the bits then yes its worth it.

[Bibbs]

Cheers Dawsey .. and I take it the NA/Turbo heads are different (as NA's are more agressive ..?)

[Dame]

Any ideas what this little lot would cost?

[Bibbs]

It's a matter of getting a rear end of a crashed MR2 .. I wanna know if the NA - Turbo's are compatable (doubt it) as I could then get a Rev3 NA head and get it worked on and then swap 'em over ..

[pizza boy]

I believe that this is possible, since AFAIK the engine blocks are the same for both generations of engine. If you changed all of the differing parts i.e. replaced AFM with map sensor, swapped injectors etc. you should end up with an engine identicle to that found in a Rev 3. 

Some of the differences of rev2 and rev3 3SGTE are:

-position and orientation of oil filter changed.

-Increased size in internals pistons, con-rods etc.

-turbo charger changed from Garrett CT26 to CT20 (same intercooler though).

-boost pressure raised from about 10 to about 13 PSI.

-power output raised from 220 to 240 BHP.

-compression ratio slightly lowered.

-injector size increased from 430cc to 540cc.

-fuel cut threshold raised from about 12 PSI to about 18 PSI.

-head and inlet path completely redesigned. TVIS removed, 8 'independent long ports' reduced to 4.

-throttle body increased from 55mm to 60mm.

-inlet valve lift increased from 8.2 to 8.7.

-different, smarter engine ECU, more tolerant of poor fuel, different connector pin out.

-air flow meter removed.

-intake manifold inlet air temperature sensor added. i.e. after turbo and intercooler.

-ECU now modulates the turbo VSV to achieve variable control of boost pressure rather than either open/full or closed/reduced. Control of boost now quite subtle when ECU is unhappy because of temperatures, detonation, speed, etc.

-location of valve shims moved. Note this makes adjusting the valve clearances a much bigger job as on the revision 3 it involves removing the camshafts.

exhaust valve clearance increased by 0.08 mm .

-oil pan changed from a one piece pressed steel part to a two piece affair, the upper half being aluminium, the lower half being pressed steel.

-No. 1 compression ring now described as 'stainless steel' in GT4 manual/supplement instead of just 'steel'. Oil ring is described as 'stainless steel' instead of 'a combination of steel and stainless steel'. No. 2 compression ring remains described as 'cast iron'.

idle speed slightly reduced .

Theres a more accurate list somewhere canny find it.

[Bibbs]

and Fensport don't have any ..

Need to find a rev3 turbo with a blown bottom end I think ..

[KiwiMR2]

turbo charger changed from Garrett CT26 to CT20

Not Garrett though

power output raised from 220 to 240 BHP

225hp to 245hp for J-specs

different, smarter engine ECU, more tolerant of poor fuel, different connector pin out.

Bosch D-Jetronic (Gen III) vs. L-Jetronic (relatively primitive) engine management to be specific.

flow meter removed.

MAP sensor instead

http://toyotaownersclub.com/forums/index.p...t=7758&hl=540cc

Cheers

KiwiMR2

[Bibbs]

225hp to 245hp for J-specs

<pedant>

Actually .. 225PS and 245PS ..

which is about 222 and 241 BHP.

</pedant>

BHP, PS etc ..

[KiwiMR2]

Actually .. 225PS and 245PS ..

True dat.....sorta like the psi, bar, and kg/cm thing.

Cheers

KiwiMR2

[Bibbs]

Just goes to show that German horses don't work as hard ..

[DeusMR2]

Just goes to show that German horses don't work as hard ..

lol :D