My RX6D turbo is dying and fuck buying a RX6R to replace it with ($2400 turbo) not to mention they don't even make them anymore. So, I'm wanting to convert my manifold from the IHI flange (elongated T25 looking flange) to a T3 flange. My manifold is a old cast iron apexi manifold, but as you can see from the dyno plot below, its already proved it can support nearly 500hp.



I'm wanting to swap to a T3 flanged turbo that will make similar, or more power. So far I'm thinking either a BW S259 w/.70 AR hotside or a GT3582R w/.63 AR hotside.

My other major question is what kind of welding will it take to do this, and how much will it cost (ballpark). I've got a turbo elbow for the setup on the car now, which i imagine could just be cut, extended and reflanged for the new turbo's outlet pattern.


Cliff notes for Martin.

1. Old IHI turbo dying
2. New turbo is going to be t3
3. Must convert downpipe/turbo elbow & manifold to work with new turbo

 

Got any pictures of the flange on it ? chances are your best bet would be an adapter plate machined to fit it, is it impossible to get a replacement IHI ?

 

Its a topmount manifold so I think an adapter will raise the turbo's mounting location into the hood. IHI stopped producing the RHC-6 series turbo and has no plans to resume production. This kinda buttfucked Power Enterprise since their turbo kits all use that series turbo, and I get a weekly email from them stating they are still hunting for someone to take over producing the RX6R for them.

Here is what my manifold looks like.

 

Rebuild the IHI. it will cost you nomore than $100 for new bearings, seals, and the thrush(thrust) washer. It comes apart just like anything else, no press needed. It is VERY SIMPLE AND STRAIGHTFOWARD. NO MAGIC! lol!

 

I need a new compressor wheel, and this is a ball bearing turbo. The few companies who specialize in rebuilding turbo's can't help me because they can't get wheels for it.

 

An adapter plate shouldnt have to be but 1/2" thick or so, I doubt welding is going to help the situation.

 

I don't. People in my predicament in Japan have been doing this for a while.

 

hea tit up to 250 degrees, mild flange, 4340 filler, backpurge the argon, done

 

And that's why I'd never buy a BB turbo. Also, If your comp wheel is fuqed then your turbo is more than just going out.

And there's your other option.

PS I likes the s256 idea! Borg warner/bulleseye turbos have been kicking ass and taking names ever since they came out.

 

1. Space cross member down 1/2"
2. I can weld on a T3 flange for about $35 + cost of flange
3. Downpipe modification will probably be around $150 + flange ($29) - Garret 4 bolt 3"
4. AC lines go through firewall on wrong side.. Your steering wheel must be on the wrong side too... Fix it.


35 R .63 will work just fine but spool later than that
30 R .63 will peak at around 500 and spool at about the same rpm as you had.


martin