Just got a vj-20

[jumpncrash]

Ok guys, so I just picked up a VJ-20, and wow is it small. I had previously purchased a vf12 which I sold/traded to another member on here for another car.

Nothing is on the car right now.

What I want to know are tips on what to do with the vj-20, how can I make the most of it. I know I should port the wastegate and possibly put a larger flapper door on it. But what else is there that I can do? I have a 26x6x2.5 fmic, gonna use 2.5 inch piping, unless I should go with smaller, and a 2.5" exhaust. The head is rebuilt pretty much th stock specs with a slight deck, and right now the bottom end is from a SOHC, but I doubt its gonna last forever, its around the 300k km mark as it is so a 9.0:1 piston will be going into a slightly oversized block after. Intake manifold is from a 2nd gen BP. OH! Injectors are 460s from a rx-7 and I will be running MS.

Right now the compressor wheel is kinda messed up, I can still use it but for my peace of mind I would like to replace it. There's a shaft for sale on here for 60 bucks, should I do that, or go hybrid. Some input from the turbo gurus, and anybody else, would be awesome.

And just because everybody loves pics







Thanks a bunch,

Nick

[FE3-323]

you need to send the turbo out with a new wheel to be balanced..... @ that point id rather say upgrade either the wheel bigger or a larger turbo.
weld in a larger flap to the hotside & port it **SOME** VF flaps work or old valves.

[mazdasly75]

Do not install this turbo on your engine!!! if the wheel breaks again, the pieces will reach the pistons and valves...

BTW You can expect 200whp from a vj20 @ 15psi. If you ask for more, the pressure will drop down to 14 passed 4500rpm.

[Mazda_Powered]

ebay has upgrades for cheap, search ihi upgrade

ya they are awfully small turbos lol

[jay]

Small but lag free pretty much. You can overcome some of the pressure falloff with a good intercooler. But yeah, I agree, that turbo's a hand grenade with the pin pulled out. Needs a new wheel for sure.

[323driver]

That wheel is useless, you'll need to send it out to be replaced and rebalanced, expect to pay. I would simply start by putting it on the car and getting the hang of it. Once you like what you see, up the boost to 15 psi and when that's not enough, change setups. I went from NA to GTX motor to GTR motor in 6 months, couldn't resist to boost, lol.

[jumpncrash]

yeah I wasn't planning on going to the max of the turbo, from what I hear it's out of its efficiency range at 15psi.
I was just gonna stick it on anyways even with the damaged wheel, the engine is sort of on the way out.
Any idea if there are any good shops arounf here that do rebalancing of turbo shafts?

Thanks
nick

[deathtrigga]

hybrid it with a vf10 or something since u already have 460's and ur gonna run ms . plus the sohc bottom has lower compression allowing you to up the boost! have fun

[jumpncrash]

yeah except the SOHC bottom end has like 300k kms on it.
I want to do something to it, but I want it done before summer so whatever it is it'll have to be done quickly.

Nick

[deathtrigga]

do a compression test, if everything is good ur good to go man. i boosted a high mileage bp and it ran for a while under heavy beating . then i blew it. now i got another high milage bp which issnt running as good as the last bp but its lasted about 10k miles now and i've beat on this motor pretty bad too.

[jumpncrash]

yeah, last check I was at 150-140-150-150
I'd have to check it again.

[deathtrigga]

thats fine dude there are lots of ppl here boosting high mile bp's if you do decide to run a vj20 you should be fine with ur bottom end.

[323driver]

Don't use it as is, it will brake and everything will be scrap, including the rest of the turbo. What I meant is fix the turbo and then use it, at whatever psi you want. With the stock sohc bottom end, I would keep it at 10-12. Just by adding a nice downpipe, you will be boosting 10-11 instead of 8-9 without any additional mods.

[Mazda_Powered]

yea, dont run that thing or you will destroy the turbo!!!! its unbalanced!! would you throw in an unbalanced crankshaft in your car? its basically the same thing dude...lol

you should just go on ebay and get the $200 cold side upgrade and have it balanced, enjoy 200hp at 10psi!

[deathtrigga]

wait i never knew about these ebay coldside upgrades how come no body really talks about them when they talk about hybrids and gaining more power out of the vj20. mostly everyone talks about the vf's. How much of an upgrade can you get from getting the ebay colside?