FAQ: 3SGTE Gen3 / Gen2 Differences

[Toobs]

Courtesy of user DavidV (David Vespremi) from board.mr2faq.com

- MAP sensor instead of AFM
- Bosch D-Jetronic (Gen III) vs. L-Jetronic (relatively primitive) engine management
- CT20b turbo replaces CT26
- Boost raised from 10psi to 13psi
- Fuel cut raised from 12 psi to 18 psi
- Different ECU
- 4 wire O2 sensor
- Shim under bucket valve shims
- slightly more aggressive cams
- Revised internals (pistons, con-rods etc.)
- Revised cylinder head cooling passages/water jackets
- Revised intake manifold (8 'independent long ports' reduced to 4)
- intake manifold inlet air temperature sensor added. i.e. after turbo and intercooler.
- Revised gearbox with close ratio gearing
- lower compression ratio
- stainless steel head gasket
- factory 540cc injectors replace 430cc injectors
- revised fuel rail with bigger bore and relocated pressure regulator
- TVIS eliminated
- EGR eliminated
- LSD in 80% of them
- throttle body increased from 55mm to 60mm
- inlet valve lift increased from 8.2 to 8.7
- intake manifold inlet air temperature sensor added
- Less restrictive exhaust elbow
- Aluminum oil pan
- more rigid alloy sump and additional oil baffles
- Factory Catch can
- Better Oil Cooler and relocated oil filter (bottom)
- 4 Channel ABS coupled with Traction Control available
- No. 1 compression ring described as 'stainless steel' instead of just 'steel'. Oil ring is described as 'stainless steel' instead of 'a combination of steel and stainless steel'.

[wagonist]

Now we need to know the differences between the Gen III & Gen IV

AFAIK:
Throttle body moved from end of inlet manifold to middle for better air distribution
Turbo turbine housing one piece with exhaust manifold (don't ask me why, I don't know)
Everything else the same as Gen III (unless someone wants to correct me here)

[Cool1]

Now we need to know the differences between the Gen III & Gen IV

AFAIK:
Throttle body moved from end of inlet manifold to middle for better air distribution

I dont understand this The throttle bodies have always been in the middle! Or are you talking about the RWD versions?

[wagonist]

Have you got a pic of a Gen II or III to post up?

I'm sure the ones I've seen came in at the end.

[Cool1]

Gen3 Intake:

[wagonist]

I got it mixed up.
The Gen IV is on the end with a shaped inlet manifold instead of a log type.

1999 Caldina GTT engine bay:


Better picture with piping for front mount:


Caldina Gen IV exhaust manifold vs MR2 SW20 Gen III:


Toobs, you might have to change the title of this thread to Gen II vs Gen III vs Gen IV shortly I can get a heap of more info on these engines & someone else on this forum should e able to provide more, seeing as he owns one, the lucky bastard.

[Cool1]

That Gen4 turbo/manifold is yuck

[Joshstix]

The only thing the Gen 4 has going for it really is the coil on plug ignition. Other than the fact it is newer and can be used in new cars for conversions.

[wagonist]

What was the most power that the Gen III was released with?

[hamgatan]

205kw in the ST205 wasnt it?

Whats a Gen III SW20 Rearcut go for these days as well?

[wagonist]

Just Jap at Kirrawee have an ST205 halfcut going at the moment (& for what's probably a reaslistic price too $4500)

[hamgatan]

sounds about right. problem is i need a 97/98 spec SW20 rearcut for legal reasons and i want the E153 as well (fob the S54 off..)

[Good Luck to Me in Finding One! Id have better luck finding a Pair of White Tits in the Kalahari!]

[wagonist]

Was the SW20 available that late?
Sounds like you're stuck with getting a Caldina 3S-GTE then. Good luck finding one of those in Oz

[Joshstix]

The SW20 was available until '99. My half cut was a 97 model.

[hamgatan]

The SW20 was available until '99. My half cut was a 97 model.

im pretty certain they ceased production mid 98 although i think they were still sold new until late 98/early 99... last SW20's were all Gen III 3SGE(Aus)/3SGTE(Jap). US Production stopped in '95.

what did your rear cut set you back? I cant put an older revision of my engine in for legal registration reasons obviously, thus im forced to get a +Jul 96 SW20 Jap Import Rear Cut with a Gen III if i want to do it right and legal.

Sounds like you're stuck with getting a Caldina 3S-GTE then. Good luck finding one of those in Oz

thats going to be an icky install i would think. gen iv into a SW20.. i dont think it would be worth it for the price and the hassles of getting it running when i could have less problems with a gen iii.. kudo's to anyone who does it though, i hope they document the conversion and post a toymods thread on it!