[russty_2008]

I have a 20v 4 age thanks to a good mate that I am in the process of rebuilding whats people's thoughts on it not worried about getting it engineered

[henno]

Rebuild it, sell it for a profit and use the cash to buy an M18.

Did it come with a gearbox? You'll need the Toyota 5speed, if you can find one the drifters haven't junked.

[atari4x4]

what year jimny & what engine is in it already... logical upgrade would be G16b or M18a, just cause the motor is free doesn't make it a viable option.

can you even legally fit it due to the age of the 4age's these days?

[droverdave]

hmmm good question on the legality due to age. I'm almost certain you can only fit a newer engine in your car.

Now they did make the blacktop 20V 4age quite late, and possibly into the year 2000s?

But you're going to need a pretty early Jimny to get close to it being able to fit.

[russty_2008]

It's a 99 jimny and a don't care about legality it's not going on the road has anyone else done it

[BlueSuzy]

Won't be much more different than a 20V in anything else. A lot will be custom.

DanK has done it into a sierra but moved the radiator into the tray door. Jim vs sierra have similar sizings, Gbox tunnel, eng mounts etc.

[Mike57]

Not that I have heard of as there are better choices.

[MrRocky]

The 4age is a fantastic motor some would say better than m18 or g16b
100kw and tough as nails with huge aftermarket upgrades and bolt in supercharged replacement.
Setting up hydraulic clutch can be gheyyyy tho

[droverdave]

Does the jimny have a separate or combined transfer case?

[greenzook89]

Seperate tcase. A relative of mine has a 4A-GZE with a 20 valve head in his sierra. He needed the T50(?) Gearbox to make it all work.

So it can be done but it is by no means a weekend job.

[droverdave]

ahh well in that case separate transfer case.

-sort out how you are going to deal with the distributor at the back of the head, most go for an aftermarket computer and modify the distributor (remove the distributor bit), and convert to multiple coils.
-sort out a plenum to keep dirt out of the quad throttle bodies, and join all the quad throttle bodies to your snorkel/airbox. The oem FWD one on the 4age faces the wrong way. I suspect this will be the hardest part.
-Sort out how you are going to do your cooling system, either use RWD 4age stuff or the ae82 fwd remote thermostat.
-5 speed t50 gearbox out of an AE86 or an AE71 corolla, clutch to suit.
-Custom engine mounts
-Custom gearbox mount
-Custom shaft between gearbox and transfer case
-An off the shelf RWD exhaust manifold might fit the jimny, or it might not.
-The speed sensor in the t50 is cable driven, so i'm unsure how you would join this to your jimny if the jimny is expecting an electric signal. Might need a custom speed signal (magnet on the tailshaft or something). Or i think there was some other speed sensor that fit into the t50 gbox (supra perhaps speed sensor? I cant remember).
-Radiator, you'll have to check if the water outlets on the 20V are on the same side as the jimny radiator, or you might have to look at something different.

This is all assuming that the gearstick on the T50 comes close to the hole in the jimny floor plan. and the big assumption is that the 20V sump doesn't hit anything when the engine is in the right spot. The 20V sump has the majority of it at the front of the engine. How does this compare to whatever engine is in the Jimny?

[Gwagensteve]

And after all that, 120Kw and 8000rpm+ will pretty much wreck the whole jimny driveline. 4age's are much heavier than any jimny motor too, adding load to the front diff which is already notoriously bendy.

Not worth it in my opinion.

[droverdave]

I personally think a better choice would be a bigport 4age with the TVIS system. The TVIS system is really good at getting extra torque at low rpms. and when the TVIS opens up it lets the engine breath (it opens at around 4500 i think). And pretty much all of the difficult issues I listed there are eliminated with the bigport 4age (inlet manifold is no issue, can use factory dizzy and ecu).

I put a bigport 4age in my old ke70, and my mate put a smallport one in his ae86. His screamed after 6000 rpm, but my bigport was way nicer to drive around town and i reckon "Faster" up to 6000rpm. I have limited experience with 20vs, so am unsure on how the 20V performs at low rpms, but they do scream in the higher rpms, which i think for a 4wd wouldn't be the most ideal. (but they do have vvti which might help low rpms compared to the smallport)

Also i think you want to be looking at the torque figures to compare which engine will be more harmful to the driveline. As power is just torque by revs. All from wiki:

bigport 4age = 131nm @ 4800rpm
Smallport 4age = 149nm @ 4800rpm
20V silvertop = 162nm @ 5200rpm
20v blacktop = 162nm @ 5600rpm
suzuki M18 = 170 Nm at 4,200 rpm.

(all factory figures, i suspect if you tune your 20V properly you will get a few more nm)

So the M18 actually has more torque than all the 4ages, just no where near the power as it doesn't make its torque in the higher rpms like the 4ages (given power = torque x revs).

So how many M18 jimnys are around and do they destroy drivelines? Also driveline longitivity 100% depends on how you drive it. Go dumping the clutch at maximum torque, and you would eventually kill the driveline with a standard engine...

Agreed with mr steve there that it is Lots of work for not alot of real world advantage. Leave the jimny alone, and put that 20V in a ke70 and go drifting!

[jake84]

Ive put a 4agze in a ke30 coup and so have a lot of my mates they are hands down a crazy motor built to withstand so much shit


Work to live, don't live to work.

[neofitou]

Dank's Sierra is pretty awesome when it comes to loud pedal, and though there are off the shelf options for the jimny now in the form of cromo axels, sierra t-cases etc, it would still break CVs and bend housings.

If your prepared to spend the time and the money to make it really work it would be terrific. (I think dank spent >$1300 just upgrading the gearbox never-mind the rest)
If not, just sell it for good money and get an M18 and save all the headache and put the extra coin on the rest of the drive train.

[vet 180]

Personally I think the m18 is a better choice. Power band is more suited to 4x4 work and a much easier conversion. IMO sell the 4age and get an m18 (assuming you have the m13 spreading in your Jim)

If dead set on the 4age try and get a w50 from a hilux and a 4a - w series bell housing.

1st it's a stronger box than the t50
2nd it's cheaper than a t50
3rd it has a much lower first gear for crawling.

The bell housing can be found in old celica's that ran the w58 and 4a engine family

Second you mentioned you have. 20v 4age..... This is the most expensive of all 4age's and the least suited to 4x4 work. It really is a high rpm motor and makes all it's power up top. It is also the hardest engine to fit due to being originally fwd. It is also the weakest engine of the 4age family as it has all light weight rods pistons etc. the earlier engines are much tougher! A rwd small port 4age would be a much better starting point.

So IMO sell off the 4a to some rolla fan boi and start with something different.

Engines I would choose instead of the 20v:

Vq30de very lightweight v6 will make good power and be reliable
Sr20de. Can be had for under $200 in de form are seriously strong make great low down tq. Parts are mega easy to get.
Ford duratec great lightweight reliable engine.
The old moo. A bit heavy but cheap and good tq
Sr20ve can make 300engine hp easy and still have great low end power with good progression
1mz reliable strong powerful v6. Not 100% sure on the weight but it is an alloy engine

[russty_2008]

Thanks for the opinions and thoughts guys I've got a t50 and extractors for it the engine came out of a Sierra but would really love to put it in a jimny just because its different the only thing that worrys me is the speed sensor does the g13b run a speed sensor that I could use for the 4age or would I have to run an after market on as drove rave suggests

Do the sierras bend diff housings with the 4a s in them