How to: Turbo Manifold design, need your thoughts

[Gold28]

Do it Rod. That 28 of yours is begging for it. A long weekend with a couple of mates introducing the 28 with a 1G and you'll be grinning like a cheshire cat again. Don't worry about the unicorn, it's spent so long in the shed it's afraid of the sun.

Hmmm friends suck don't they.......

[TheToyman75]

Anthony,

Your a Bastrd !

When I was debating selling Joe's old TA23 the only way I could bring myself to do it was to lend it to Josh for a few weeks and sell it before I got it back.

With the RA28 I gave it a wash and put it under a sheet and a car cover so I couldn't see it while I tried to decide. I can sell it and finish the unicorn allot quicker or hang onto it and end up with both eventually.... I was really leaning towards selling it until this and the damn "phoptchop" thread.

The last 1G RA28 sure was fun to drive and its not a difficult conversion or all that expensive in the scheme of things. Mind you Mos might bitch slap me if I suggest he wire up anything else for me this side of Xmas.

[Gold28]

Or you could leave it in the back yard for 18 months and sell it to me. I'll be looking for something fun when I get back.

Maybe I should find this photochop thread.

[RAd28]

when i fitted the engine i was told they have a habbit of leaning out in high RPM, so ditching the stock fuel regulator in favour for a malpassi was a good way of picking up the top end...

144.2kw might be nice, but after seeing kirks silver/grey GA28 going with 200+kw.. that's nicer! though he's still got the stock turbo setup, just high flowed...

[TheToyman75]

leanout ??? On stock management the 1GGTE gets rich not lean ??? It will only run lean if your injectors are too small fo rthe output (Not a problem for you) or your fuel pump can't cope.

Fitting a rising rate reg is considered the dodgy fix to overcome to small a fuel injector but it will overwork the fuel pump and is frowned apon by anone who deals with real performance vehicles. Or have you just increased the base pressure a few PSI to squeeze some more out of the stock injectors ?

Larger injectors really are not that expensive if you find a good set of alternate factory ones that fit. If you still have the factory reg I'd personally be refitting it.

[RAd28]

well i had been suggested that it runs lean, and had been the cause of a few dead engines/prematurly buggered, and i heard that around the forums, i wasn't about to argue with something that might save my hard earned $$$$ and to be honest, i didn't know better.

as for tuning it, we installed it straight out of the box, and she ran fine, then tuned it from there according to idle speed, black soot in the exhaust pipe, and fuel econ. not the right way to do it i know, but at the time we had VERY limited equipment, if you look at the conversion pics, it was done in the garage of a driving school, and other work was done in an underground carpark of a unit complex... couldn't afford to send it to a dyno shop either...

but now it's off the road, (crash damage) and i'm going over all the things i couldn't do properly the first time, and looking to make a few extra HP along the way...

[kingmick]

Suggested wrong, every boosted toyota run rich for saftey

[RAd28]

fair enough then... i was under the impression it was just a weakness... 7M has poor head gaskets, 1G has poor fuel reg... my bad...

[1jzracing]

few people on this thread were interested in a custom 1gg manifolds

i finally got around to building the first one the other night so here are the pics, looks like it should work pretty well.

It took plenty of hours and just the parts cost me heaps so if someone wants one its $750 all stainless fully purge welded and i was careful to allow clear path for oil drain and turbo outlet etc.

turbo flange is a t25/28 frame (pictured HKS 2540) it sits slightly closer to the block and lower than the std twins

[RAd28]

fark yeah! that's impressive! only concern would be fitting one under the bonnet of the '28... when you say lower then the std twins, you mean there's MORE clearance above the turbo?

[JustenGT8]

Nice, those long runners will boost on nice and smooth....should be very predictable to drive

[1jzracing]

fark yeah! that's impressive! only concern would be fitting one under the bonnet of the '28... when you say lower then the std twins, you mean there's MORE clearance above the turbo?

yea more clearence... the twins have all the piping etc above the turbos and this set up doesnt stick up as far, you can clock the front housing around so the outlet pokes nicely across the top of the cam cover if you want too

[RAd28]

definatly something to think about... thanks mate,

[Quint]

Just bringing this back to life.

1JZ, you still making manifolds? made myself up a dump pipe for my standard CT12s, works really well, wouldn't mind getting a new manifold made up. Let me know, cheers.