Is a 4AG(T)E better than a 3SGTE?

[Lurkin]

Here in Melbourne ae71s are reasonably common.

The point being is that they look like a ke70, but came with a 4ac = 4a mounts/ cross member etc

much easier to get a *age in there than 3sge.

Also easier to get engineered [read: certified].

And 7afe bits are easy to come by...

[Lith]

I hate the 3S series.
Everyone I know that has tried to race them had had problem after problem with them
and have spent way more on them trying to keep them going than they ever planned on.

What problems have they had, out of interest?

[Dell'Orto]

Most circuit racers I know have had issues with running bearings.

[Lith]

I'm guessing its an oil control thing?

[matt dunn]

Most circuit racers I know have had issues with running bearings.

Headgaskets, blocks, bearings, oil leaks causing fires, and generally poor performance.

[Mr Revhead]

Yeah ages ago but I recall a ST185 and an SW20 attempting to bake themselves at levels.

Also, do not confuse the JTCC engines with 3stges. They are not. They are purpose built TRD race engines. Different blocks etc

[GDII]

I believe they have a different engine name too. They sit upright like the Altezza engines.

[rollaholic]

it seems to me there are a few issues contributing.

one being the chassis availability as mentioned. people wanting 4WD 2L turbo are (without wanting to start a flame war) probably better off going subaru or mitsi.

second, it seems that the 3S needs a fair bit of money spent to get good results from, whereas the 4AGE its possible to get good results with relatively small outlay (particularly in the lighter cars they tend to be found in - 150kw is lots of fun)

if someone is looking to spend a bunch of money on a toyota, unless they particularly love the above mentioned 3S platforms they are probably going to be more inclined to go with something JZ powered.

so the budget builders go with the 4AGE, and the guys with more cash tend to prefer JZ stuff (for obvious reasons) particularly in todays drift happy world. which leaves the 3S as a bit of a niche market.

[Dell'Orto]

Most circuit racers I know have had issues with running bearings.

Headgaskets, blocks, bearings, oil leaks causing fires, and generally poor performance.

Headgaskets would have to be a tuning or assembly issue surely, and oil leaks would also be assembly or maintenance. Nothing inherently wrong with the engine. I'm not surprised by Gen 2 motors running bearings with their weaksauce sump setup, and neither am I surprised when they are uprighted and run bearings.
Blocks, well yeah...

[DeeCee]

so with respect to the oiling systems then, the gen3 3S has the windage tray with a baffle. Does the 20V 4A have similiar or are we really looking at the orientation with regards to oiling issues?

[Bazda]

You can get a 4agze block, stick on a 20v BT head and easily get 270kw atw on around 22psi.

If you want more go E85 or Q16 fuel and run 30psi which will net you 360kw atw.

Not sure if a stock 3S bottom end will hold together at 30psi?

[Dell'Orto]

so with respect to the oiling systems then, the gen3 3S has the windage tray with a baffle. Does the 20V 4A have similiar or are we really looking at the orientation with regards to oiling issues?

The silvertop 4AGE is similar to the Gen 2 sump, though the 4AGE has a full length baffle vs the little stubby one around the oil pump pick up the 3S has.
Dont see why a properly tuned 3S wouldnt handle 30psi, the bottom end is as strong as anything else. Pistons may be a weak point, but Gen 3 are teh same construction as 4AGZE.

[DeeCee]

I didn't think it was that bad? Or are you referring to the depth of the baffle to the depth of the pickup?

[Dell'Orto]

Those are Gen 3 arent they? The Gen 2 one I have in the shed is tiny, as the baffle plate is mostly in the sump. 4AGE one is deeper too I think

[DeeCee]

well i was looking at the potential of the later revision engines, where fixes/upgrades are commonly made. If we are looking at earlier versions of engines, let me know but I was under the impression we were looking at the family bloodlines across the years.

[7ishNZ]

I tried to upright a Caldina gen 4 bolted to an altezza 6 speed... sump was baffled and had swinging gates, 6 litres of oil... lasted 2 laps round Ruapuna before the bearings went. Right hand sweeper killed it.
I believe they tend to hold oil in the exhaust cam cover till there's not enough left in the sump... some have tried adding another drain to the sump ( 3sge altezza has one stock) at the back of the head.

Dry sump and more oil seems to be the answer.

[Dell'Orto]

well i was looking at the potential of the later revision engines, where fixes/upgrades are commonly made. If we are looking at earlier versions of engines, let me know but I was under the impression we were looking at the family bloodlines across the years.

Oh right, yeah I was referring to Gen 2 with bearing issues...never heard of a Gen 3 doing it when its not been stood up. Its a shame there were less Gen 3 SW20 turbos brought in to the country, I think they would have improved the 3SGTE reputation substantially!

[iOnic]

From what I've seen. Block cracking seems to only happen on big power/harsh environment 3SGTE's that have had their bores enlarged (this results in thinner walls between #2 and #3 cylinders.

The question of whether a 3SGTE can hold together on 30psi = yes depending on the turbo. 30psi on a T3/T4 is very different to 30psi from a GT45 - but the general gist of things is that a stock 3SGTE bottom end is stronger than a stock 4AGE bottom end.

Not really sure why this is a discussion tbh. They are two very different engines with different applications and both do a good job. They're not really interchangeable with each other without a lot of effort. Upright 3SGTE's shouldn't even come into it. If you laid a 4AGE on it's side you'd get much the same results.

This is taken from elsewhere. Talking about 3SGTE's and pretty much matches what I've seen in various xSGTE builds.

Gen1-gen3 pistons are good to about 400whp
Gen1-gen3 rods with upgraded bolts are good to 500-600 whp
Gen 4 rods suck
Gen1-gen4 cranks are good to 1000+hp
Gen 1 & 2 blocks are good to anywhere between 600 and 700whp before the risk of cracking becomes high
Gen 3 blocks are generally considered to be weaker than gen 1 or 2 blocks
Gen 4 blocks are the strongest of the 3s blocks, have a better casting design and better metallurgical properties but the actual HP numbers are still largely unknown.
Brand new blocks bought directly from the dealership are similar to the gen 4 blocks.

*the 98+ 5s block can handle basically a jillion HP...

[iOnic]

Bit more info on the JGTC Supras/3SGTE's

The engines fitted to the A80's were definitely 3SGTE's. Could they have used a 4AGE instead? Of course. Could the 4AGE's have made 500hp? Sure. Could they have made the monstrous ~640nm of torque these things had at ~4500rpm? Doubtful. Would they have had the reliability for endurance racing at this level? Almost certainly no.

Is the 4AGE better than a 3SGTE? Different horses for different courses. I own one of each and like them both for different reasons. I wouldn't trade one for the other.

Here are some pics anyway.

















WRC Corolla






This is a 503e engine. It is the race engine that was used in Le Mans/Pikes Peak that the production 3SGTE is based on. Displacement varies from 2.0 to 2.5, they had a CR of around 7.0:1, had dry sump lubrication and made anywhere from 600hp to 1000+ depending on state of tune. The turbo they ran was only described as a "CT26R" and boost pressures of 50+psi weren't uncommon.









In an SW20

[Mr Revhead]

Those engines in the supras are called 3s for marketing only. They are a version of the 503e. They are not 3sgtes as found in anything else