so i am trying to go with a 90mm TB swap on my DD w/ the M112 Radix. currently its got the OE setup with the 3 bolt flange and stock truck 76mm TB and 3 bolt j tube. my questions are this:

-how much does a 90mm 4 bolt J Tube cost from Magnacharger?

-is the inner diameter of both J-Tubes the same? from looking at pics of a 3 bolt and 4 bolt next to each other the only difference appears to be the flange. the tube diameter itself seems to be the same. anyone ever measure it?

i am trying to save some money here, and got an idea- but it depends on what the cost of the new J-Tube from Magnasun is... I found this adapter from CBM which is only $80. i know even if i left it tapered like it is, id see a gain. but i want the full gain from the 90mm. SO if- IF - the 2 J-Tubes are the same diameter i would buy this spacer, bolt it on, and hone/bore the hole out to match the 90mm TB perfectly. this would yield me the exact same results.

so, anyone have measurements or can take any, even from outside? thoughts, opinions...?

 

This tells the story.

 

no i know the opening at the end is obviously the size of the TB, im talking about the actual J-Tube inner diameter- PAST the TB flange. remember early on when WCCH made 90mm conversions? they cut off the 3 bolt flange and welded on a custom 90mm billet piece. so my thinking is, they couldnt have possibly ported the ENTIRE tube its too long and narrow especially the end that mates to the blower.

i need to know this- the 4 bolt flange and J-Tube are clearly the same size... however, the 3 bolt smaller flange is so dirty i cant tell if after the flange the tube gets larger (which i believe it does). IMO the outer diameter of the tubes appear to be the same so why wouldnt the inner diameter? can anyone take a picture or a measurement inside the 3 bolt flange, maybe light up the tube for the picture...?

 

The tube itself is larger than 90mm. Others have just modified or replaced the flange. There are some old threads on here if you do a search.

 

Look at where it bolts to the blower in AK's first picture... thats deff alot bigger ID..

 

Is that a MP112 tube....looks like a different bolt pattern?

 

ohhh just saw that... maybe its a TVS unit?

 

Those are both MP112 inlets.

OP, they go for around $150 used when they pop up. Not sure if you can still buy them new or not.

 

I'd sell mine for 60 shipped....it's ported, on the right:

[IMG]http://i616.photobucket.com/albums/tt247/jschrock85/IMG950088.jpg[IMG]

 

thats a very good option... mind sending me some more pics? its kinda blurry/hard to see well in that one
kelleyperformance@hotmail.com
i have been posting WTB every fing where and nothing... a rash of them just sold within 6 months but everyones going TVS now and thats my plan just this is a cheap gain for a particular high stakes race my big mouth got me into

i disagree. it seems they dont use that top middle bolt but other than one being clean and the other coated in oil and grime (makes it look smaller) it would have to match I.D. of the back of the case. if it didnt, there'd be a big step all the way around the inlet on the back of case and that just wouldnt make sense, theres alot of engineering into these IMO. i think picture is deceptive
like the WCCH ones they first started doing in 06'??? thats my plan.... they HAVE to be the same big(er) diameter past the flange... both tubes look like they are cast the same just different flanges...?