[Mk2] [Turbo] Rev3 Conversion

[joola89]

I have a opportunity to convert my rev2 tubby to a rev3 tubby, but i don't know what i'm gonna to gain out of it besides power!

The reason why i'm considering it, is mainly because i suspect my head gasket has gone. I'm losing plenly of water.

Is it worth doing (engine swap)?

Also, is it possible to keep the rocker cover and intake plenum from the rev2 and fit onto the rev3? In my opinion they look better, just incase i forget it's a 'Toyota', '2000 twin cam 16', 'twin entry turbo'.

[Century Motorsport]

You realise to convert fully to rev 3 you need to change the ECU and a few sensors as well as the motor? If you don't, you won't get all the benefits of the extra power as you will retain the air flow meter.

The rev 3 rocker, & manifolds aren't interchangable. The throttle body it also bigger on a rev 3.

If you get the chance, its definately worth doing - you'd be amazed at how much more power you can get out of a fairly stock rev3 compared to a rev 1/2.

[joola89]

Yes i understand, i've have a sourced a full rev3 donor. Someones half finished project. I'm gonna have a list of spare parts for sale.

We're talking poly carb windows, new still boxed BC coilovers, a carbon GT wing, my old rev2 engine and many more.

If you're wondering why not fix up the donor car..... it's not worth doing, as my rev2 is in a much better condition.

[kennym]

If you get the chance, its definately worth doing - you'd be amazed at how much more power you can get out of a fairly stock rev3 compared to a rev 1/2.

I thought once your power target was above 400whp there really wasnt that much between rev1/2 or rev 3 as most of the rev 2 power limitations would have been changed by then & both heads would flow over 600 bhp anyway..........and what with cheap US parts rev 2 was cheaper......

................thats a question as much as a statment,.....im not looking to be a smart ar$$

[Century Motorsport]

If you get the chance, its definately worth doing - you'd be amazed at how much more power you can get out of a fairly stock rev3 compared to a rev 1/2.

I thought once your power target was above 400whp there really wasnt that much between rev1/2 or rev 3 as most of the rev 2 power limitations would have been changed by then & both heads would flow over 600 bhp anyway..........and what with cheap US parts rev 2 was cheaper......

................thats a question as much as a statment,.....im not looking to be a smart ar$$

To a certain extent your right. To achieve 400hp on either motor will require an aftermarket ECU (amongst other mods) and that will take away most the issues the rev 1/2 have with the AFM.

However, a few key points as to why a rev 3 motor is a better starting point -

1) Rev 3 has MLS head gasket vs paper of the rev 1/2
2) Rev 3 has a far better inlet manifold design
3) Rev 3 has bigger throttle body and inlet track
4) Rev 3 head is FAR superior in design
4) Rev 3 has shim under bucket cam followers
5) Rev 3 has a better oil pump
6) Rev 3 has a better sump pan
7) Rev 3 has bigger injectors std (440 vs 540)
Rev 3 fuel rail will accommodate 500+ hp without modification

The ONLY thing the rev 3 has against it is the suspicion of weaker blocks - they seem to be more prone to cracking..... although, I don't think there are any conclusive answers on this.

[mrdb]

4) Rev 3 head is FAR superior in design ( Rev2 head has better ramp angle and flows more than rev3, proven on flow bench ( search for chrisk on gt4 sites (same engine )))

Rev2 produces more torque at same HP .....

[kennym]

Century,thanks for your reply, as said Inyour post most of the points you make head gasket, injectors, ecu would be changed, can the rev 3 sump and oil pump be used on a rev 2? as for flow rates i think either head will be good for a track car with a reasonable useable power goal

(old hand at engine building fairly new to mr2's)

thanks ken

[RyanRs]

One thing i would look into with a rev3 upgrade is possible problems with losing power at high revs.

I cant remember off the top of my head what happens but iirc, after 5krpm the motor seems to fall flat on its face. Why? i don't know.. in fact i don't think anybody knows, but most solve the problem by fitting an upgraded EMS such as a PFC. I think JimGts had this problem.

[Lee @ 3S Service Centre]

4) Rev 3 head is FAR superior in design ( Rev2 head has better ramp angle and flows more than rev3, proven on flow bench ( search for chrisk on gt4 sites (same engine )))

Rev2 produces more torque at same HP .....

dont believe everything you read on the internet. we have seen it time and time again where a rev 3 head on the same engine setup always produces more power. i also know other tuners have experienced the same thing

[RyanRs]

4) Rev 3 head is FAR superior in design ( Rev2 head has better ramp angle and flows more than rev3, proven on flow bench ( search for chrisk on gt4 sites (same engine )))

Rev2 produces more torque at same HP .....

dont believe everything you read on the internet. we have seen it time and time again where a rev 3 head on the same engine setup always produces more power. i also know other tuners have experienced the same thing

I personally think that a lot of people assume that more flow is always better, so where the rev2 head has larger ports or what not and therefore flows more air than the rev3 people just straight away assume its the head to go for; but the rev3 head has probably been designed with velocity in mind which is what matters more. Generally when you open the ports up past a point you gain flow but loose velocity, this causes a negative effect on bottom ~ mid power/torque and only gives room for improvement on the top end. Im under the impression that the gen 2 ports was designed to be 'large enough' for a 2.0L engine but on the rev3 + yamaha tuned the ports for optimal efficiency.