12H supercharged? Has anyone done this?

[sco_aus]

Im looking at doing a 12H conversion on my HJ75 troopy and am wondering if anyone knows of one being supercharged? I was thinking of using the Toyota SC14 as it has a much better flow rate than the SC12. Maybe 2xSC12s :thumb:

I have a bit of experience with turbos and whilst i rate them on a performance level, they just arent as good as a supercharger up hills and in low rev situations and since im building this troopy for towing, it would suit it. I will and do go offroad too, so it will suit that aswell.

Any thoughts?

[HDJ105]

Why would you bother? I think you need to do a bit more research to see why the s/c would be "better" than the turbo.

Find the 12H-T first, bolt it in as it comes and see how it goes first.

[beast2h]

stick with the turbo!!

[crack]

mate bought my sc14 off me to put on his troopy. not sure if hes started putting it in yet but ill find out and let ya know the story.

jack

[sco_aus]

Why would you bother? I think you need to do a bit more research to see why the s/c would be "better" than the turbo.

Find the 12H-T first, bolt it in as it comes and see how it goes first.

Like I said, SCs are so much better on hills than turbos and whilst yes turbos are an improvement over NA, they lack the response and torque I want. Also, if the 12HT is anything like the 2H it wont want to rev out, so there is no point in having a turbo that works best when it has higher revs. And i do realise that there wont be much lag on a small turbo and only running low pressure, but I would be running similar pressure with the supercharger, so it just makes nothing but sense to me.
I have a turbo car and 2 of my friends have SC12 corollas and the datto had nothing on the hills compared to the other guys.

So anyway, this is why I brought this question up, this is me doing specific research as I know what the difference is. I also hate doing things twice when improving vehicles as it cost me a small fortune doing that on my Datsun.

mate bought my sc14 off me to put on his troopy. not sure if hes started putting it in yet but ill find out and let ya know the story.

jack

Thanks heaps mate, that would be awsome.

[Sprinterboy]

Steeling my ideas! LOL

...................and 2 of my friends have SC12 corollas and the datto had nothing on the hills compared to the other guys................

COROLLA!!!! it's a levin!.................... and its sc14.........:p

I think SC'ing the crappy donk thats currently in your troopie now and see how it goes. worth a shot. If it doesnt work out, back to stock and I'll buy the SC!, can't see the current in the sprinter one liking 18psi to much.....

[crack]

what u were saying about torque not being enough with a turbo, i turboed my 2.8lux and the torque has just about doubled.

[Sprinterboy]

I think what scott is trying to say, is the useable torque in the rev range is his main concern, and going SC instead of Turbo may provide that extra grunt where it's needed most. low in the revs

Your mate should be able to shed some light on the subject to see if the project is worth starting or just leaving on the drawing board

[sco_aus]

Bingo, cheers J. the rev range is what i mean. Since I dont even rev my 2H past 2200rpm, having a turbo just seems to be pointless. But I really want to see how a 12HT goes before I make any decisions.

P.S im certainly not bagging turbos, just think this is the better option for me.

[roscoFJ73]

Bingo, cheers J. the rev range is what i mean. Since I dont even rev my 2H past 2200rpm, having a turbo just seems to be pointless. But I really want to see how a 12HT goes before I make any decisions.

P.S im certainly not bagging turbos, just think this is the better option for me.

I had a 61 series with the 12HT and if there was one fault, it was the lag before the the turbo.
I think this is a great idea. One of the cool things about SC is you can alter the drive pulley sizes to control SC output.
The Sprintex blowers spin at 3x engine speed

[HDJ105]

Bingo, cheers J. the rev range is what i mean. Since I dont even rev my 2H past 2200rpm, having a turbo just seems to be pointless. But I really want to see how a 12HT goes before I make any decisions.


Good idea to drive first. I reckon the 12H-T will be fine with a turbo. Remember a s/c made for an petrol engine much smaller won't work efficiently on the big diesel.

[quick60]

Well I've had a Sprintex s/c on a 2H and on a 1HZ, and I've had an intercooled turbo 1HDT, and now the FTE, but of course modified. I agree that the s/c give great boost at real low revs, but you wont be towing at those revs, more like the 1800rpm upwards. A turbo can be set up to perform well in these revs, and the Toyotas generally are strongest around these revs, and can be made to come on stronger at much lower rpm with a few simple changes. The s/c will use more fuel, and because the boost is linear, will not provide the same performance as a turbo. ie, boost would be set a maximum at max rpm of 4000, meaning boost at 2000 is about half, where aturbo, boost can be set to maximum at 1800rpm, right where you want it for towing. In your case, your other s/c'd engines were petrol, which is a whole different ball game to diesels, as a 12HT produces maximum torque somewhere around 1800-2200 rpm.
My thoughts, from past experience, would be stick to the turbo on the 12HT, and possibly look at a good exhaust elbow and high flow system (something like the Beaudesert one) and possibly look at intercooling. This will give you far more useable power than a s/c, and will run a lot more efficiently and cooler. Next option, do an engine swap to a 1HDT ?
I don't think I'd ever go back to a supercharger on a diesel again, given the maintanence problems I went through with the others, particularly when used off road.

[sco_aus]

Awsome, thanks heaps for that, thats what I was after, someone who has done it before.
I think it has made my mind up to stick to the turbo, though i still want to drive one to make sure.
And as for the 1HDT, maybe when im making better money and can afford to upgrade troopies, but i dont want to do a major conversion again, its way too much money, time and stress.
Maybe ill go for the turbo V8 diesel and chuck it in a 79 series troopy[dreams].

Thanks for everyones opinions, big help.

[Alistair]

i had a 12ht powered 60, and it went pretty good stock, but spooled a bit quicker with exaust droped off b4 the muffler, so if a non restrictive exauste was on it it would spool quite fast. i had boost coming on at about 1100 rpm. and it pulled all the way to 3 grand, and closer to readline in the higher gears.

im thining bout doing a new 4wd sooner or later, and am thinking aobut a 40 wiht a 12ht, it impressed me that motor did.

[sco_aus]

Yeh it seems to be the motor of the century that thing, I havnt heard a bad thing about it yet. Can anyone tell me what the stock boost is on a 12HT?

[Alistair]

bout 4 point something, to 7 i think. i cant remenber, it was in the cruiser gregories, but i havent seen my gregories for the cruiser in about 2 years.

[sco_aus]

Thats what i thought it would be. So now to the question of what needs to be modified when doing the conversion to a 12HT from a 2H? I realise the intake and the exhaust would.

[Alistair]

only the exauste, intake with a 12ht is on the right hand side, even though the turbo is on the left and the air intake on the right, so the air coming in goes over the top of the motor from right to left, into turbo, and then boosted air back over motor left to right and in to motor. so the motor should just need the flexi join between the intake manifold and the airbox.

apart from that, as i am aware the 2 h and 12ht engine mounts are the same. and if you get the 12ht with the turbo dump pipe, if the two flanges under the passenger seat dont match, just wire it up and drive it to an exauste joint and get the rest done,

i drove my 12ht around like that, and i wasnt loud at all. did have a bit more noise, like turbo spool noise, and a bit of a grunt, but nothingthat drew much attention.

[sco_aus]

sweet, i figured it would be pretty easy. Thanks mate.

[sco_aus]

Would I need to upgrade my radiator? I dont have any cooling problems at all, but turbos put a fair bit of heat out, speaking of which are the stock turbos water and oil cooled or just oil?

[Alistair]

um i never looked into that part of the system, but obviously it rn oil for lubrication.

i dont think it would be heating it up to much at stock boost, if you raised it it would though.

but diesels run cooler any way so it shouldnt be a problem that i can see. but if it did im sure you could souce a 60 series 12ht raddiator and adapt it to the troopy.

[sco_aus]

Didnt they release a turbo HJ75? If they did a friend of mine works at repco, so i should be able to get it cheap anyways.

[Alistair]

yeha im pretty sure the turbo was avaliable with the 75, but i am unsure. just talk to the wrekers, i dont know how much of a help repco will be, asfar as im aware places like that dont sell whole engines do they?

[sco_aus]

I meant the radiator, they do whole radiators and parts. But yeh they do do short engines, but you dont want to touch them, pretty shotty work.