1G 3S: small valves, low lift short duration cams, large port design, cc's, flow rate
- rectangular intake ports, W 61mm x H 39mm
- oval exhaust port, W 38mm x H 33mm
- int. valve 33mm dia.
- exh. valve 28mm dia.
- lifter dia. int/ext. 28mm
2G 3S: larger valves vs. 1G, higher lift and longer duration cams vs. 1G, small port design, cc's and flow rate.
3G 3S: larger valves vs. 2G, higher lift and duration vs. 2G, larger port design vs. 1G, cc and flow rate, shimless buckets, VVT
4G 3S:
Note: 3S engines came in two versions NA(GE) and Turbocharged(GTE). Regardless of what induction the engine is the same generation heads both share the same designs internally except for the cam profiles ie. valves, lifter, springs, retainers....so a 1G 3S-GE head is the same as a 1G 3S-GTE head with the only difference being cam profiles.
Interchangeablity:
For many years now race teams have known the benefits of swapping parts out of the head to gain performance. Some of which include swapping lifters and cams.
Valves, lifters, springs, retainers, cams are all interchangeable between the GE and GTE heads of the same generation designation. With the turbo versions, swapping out the GTE cams for GE cams of the same gen. will yeild more HP. Reasons being that the GE cams have a longer duration and higher lift. Swapping GTE cams into a GE head will yeild negative effects if the engine is going to stay NA. Another performance upgrade is to swap the lifters out in favour of 1SZ-FE shimless bucket lifters into 1G 3S heads. This same mod can be performed on 2G 3S heads by swapping out the lifters in favour of 3G 3S shim under the bucket lifters. This mod will allow one to use high lift cams so that one can rev the motor higher in the RPM band without the fear of spitting a shim.
Note: Most parts are backwards compatible. ie. 3G 3S shimless buckets into a 2G 3S head, 3G 3S cams into a 2G 3S head. However there are some cases where this does not apply, most noteably with the 1G 3S. ie. 3G&2G 3S cams and shim under bucket lifters do not swap into 1G 3S heads.
FAQ:
Q: Whats shimless or shim under bucket lifters?
A: The stock bucket weighs 1.6 oz. & the MRS(MR Spyder) weighs 1.03 oz. That is a weight savings of 35.5%. When high lift cams are used with stock lifters it has caused the shims that are used for adjusting cam/lifter clearance to fly out. This eliminates that by eliminating the shim all together. That lightens the valvetrain weight and allows higher RPM limits.
Q: Shim under the bucket shilmess buckets are they the same?
A: NO. 3G 3S/1ZZ-FE buckets are shim under bucket, where as the 1SZ-FE buckets are shimless buckets
Q: Can I use 1ZZ-FE lifters in my 1G 3S head?
A: NO. 1ZZ-FE and 1SZ-FE engines are different so the buckets are as well...
Q: Can I put 2G 3S cams in my 1G 3S head?
A: 2G 3S cams are not impossible to fit in 1G 3S heads just improbable cause the cost would be the same as swapping in aftermarket ones...
Q: Do I need to do the lifter conversion when I swap cams?
A: If you plan on only swapping GTE cams in favour of GE ones than the bucket conversion is not nesscessary, however if you plan on going larger it is recommended you go the shimless or shim under the bucket conversion...
Q: Is their any speacial machining of the head involved?
A: I would belive that regardless of generation head if you go with really high lift cams machining of the lifter followers may be needed...
Q: Will my engine be an interference one?
A: When going high lift cams one has to take into account valve to piston clearence(VTPC)...most auto manufactures leave a little room for VTPC so one can go with higher lift cams without it becoming an interference engine, but keep in mind that there is a point that machining will need to be done...also decking a head changes these values...
Q: What kind of HP gain can I expect from swaping GTE cams to GE ones?
A: IMO swapping GTE cams for GE cams is a inexpensive mod and will yeild HP gains, if you plan on wanting more afterwards I would suggest in a set of adjustable cam gears before going with bigger cams, besides in most cases larger cams will nessessitate the need for adj. cam gears...sometimes a little more performance can be found by adv. the intake cam and retarding the exh. cam a few degrees...keep in mind that doing so changes the ignition timing cause the dizzy runs off one of the cams...dialing in cams should only be done on a dyno, and the ign. timing should be re-set whenever changes are made...i wont go into how to do this cause that would require a new thread in it self...
-tuning, tuning, tuning...sometimes a few hours on the dyno will yeild a better bang for the buck than any performance mod one can "bolt on"...
For refference:
-1SZ-FE shimless bucket for 1G 3S heads:
Part Number Lift
13751-23030 5.12
13751-23040 5.14
13751-23050 5.16
13751-23060 5.18
13751-23070 5.20
13751-23080 5.22
13751-23090 5.24
13751-23100 5.26
13751-23110 5.28
13751-23120 5.30
13751-23130 5.32
13751-23140 5.34
13751-23150 5.36
13751-23160 5.38
13751-23170 5.40
13751-23180 5.42
13751-23190 5.44
13751-23200 5.46
13751-23210 5.48
13751-23220 5.50
13751-23230 5.52
13751-23240 5.54
13751-23250 5.56
13751-23260 5.58
13751-23270 5.60
13751-23280 5.62
13751-23290 5.64
13751-23300 5.66
13751-23310 5.68
Note: Shim and bucket is one piece.
This motor is found in the Canadian Hatchback Echo.
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-3G 3S shim under the bucket for 2G 3S heads:
13751-88460 - bucket
Part Number Lift
13753-88003 2.50
13753-88053 2.55
13753-88103 2.60
13753-88153 2.65
13753-88203 2.70
13753-88253 2.75
13753-88303 2.80
13753-88353 2.85
13753-88403 2.90
13753-88453 2.95
13753-88503 3.00
13753-88553 3.05
13753-88603 3.10
13753-88653 3.15
13753-88703 3.20
13753-88753 3.25
13753-88803 3.30
13753-88853 3.35
13753-88893 3.39
Note: Shim and bucket are two pieces.
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1G 3S-GTE head 88-89 Celica Alltrac
1G 3S-GE head 86-89 Celica GTS
88-89 Carina
2G 3S-GTE head 90-93 Celica Alltrac and MR2
2G 3S-GE head 90-93 Celica and MR2
88-92 Corona
90-93 Carina
3G 3S-GTE head 94-99 Celica Alltrac and MR2
97-00 Caldina
3G 3S-GE head 94-99 Celica, MR2, Carina E
95-97 Caldina
94-98 Curren
4G 3S-GTE head 98- Caldina
4G 3S-GE head 97- Caldina
98- Altezza
