Large Tube TPI runners
Thread Starter
Le Mans Master
Joined: Jul 1999
Posts: 5,009
Likes: 38
From: jackson nj
Large Tube TPI runners
I'm looking for help from anybody with the 1.75" runners made by AZSpeed (old Arizona Speed & Marine) or the TPIS large tube runners (which AZSpeed claims they make for TPIS) on their cars. On my car, an 89 auto, the biggest problem is the detent cable fitment. The runners I received have a smaller tube on each side, but the side that would have had the 9th injector on it has the tube blocked off with some form of rubbery filler in it, which seems to be factory installed but the real problem is that tube itself. This tube on the drivers side will not allow the detent cable to fit the bracket when on the inside of it, and if you try to fit the detent cable between it and the large runners, there is not enough room to pass the adjustment portion of the cable thru. It may be possible to route the "small end" that goes to the transmission between these tubes, but I don't even know if there is enough room for that to pass thru. I've called AZSpeed and emailed, and have not gotten a reply from either attempt...I guess customer service is not high on their list for these older cars...so I'd like to know if anybody else has had this problem. I'm still wondering if I received the 89 runners or if the runners I received are for the 9th injector style, although the AZSpeed website shows the tube on both sides.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
I think it's likely they have one mold for each side. And, when the later-style setup is ordered, you receive a set with the CSI tube filled. Sounds like what you're seeing.
I've seen lots of LT TPI setups modified with burrs/grinding to accomodate injectors, cables, etc... Can you file off enough to accomplish your goal? If the CSI tube is plugged (top & bottom) like it sounds, it wouldn't matter if you had to pierce the tube with your filing.
Looks sure, function no.
I've seen lots of LT TPI setups modified with burrs/grinding to accomodate injectors, cables, etc... Can you file off enough to accomplish your goal? If the CSI tube is plugged (top & bottom) like it sounds, it wouldn't matter if you had to pierce the tube with your filing.
Looks sure, function no.
Thread Starter
Le Mans Master
Joined: Jul 1999
Posts: 5,009
Likes: 38
From: jackson nj
What brand runners do you have on your car in the pictures? I see your car is an 88, so you do have the 9th injector or did you delete it? Either way if you have the ASM/TPIS large tube runners then you also have the small tube under the large outer tubes on both sides (you can see it on the pass side photo but not the drivers side) and the end of the detent cable where you adjust it does not fit between that small tube and the large runners, did you install yours by removing it at the trans and sliding it thru that way?
Thread Starter
Le Mans Master
Joined: Jul 1999
Posts: 5,009
Likes: 38
From: jackson nj
I think it's likely they have one mold for each side. And, when the later-style setup is ordered, you receive a set with the CSI tube filled. Sounds like what you're seeing.
I've seen lots of LT TPI setups modified with burrs/grinding to accomodate injectors, cables, etc... Can you file off enough to accomplish your goal? If the CSI tube is plugged (top & bottom) like it sounds, it wouldn't matter if you had to pierce the tube with your filing.
Looks sure, function no.
I've seen lots of LT TPI setups modified with burrs/grinding to accomodate injectors, cables, etc... Can you file off enough to accomplish your goal? If the CSI tube is plugged (top & bottom) like it sounds, it wouldn't matter if you had to pierce the tube with your filing.
Looks sure, function no.
Race Director
Joined: Jun 2004
Posts: 13,966
Likes: 709
From: WI
What brand runners do you have on your car in the pictures? I see your car is an 88, so you do have the 9th injector or did you delete it? Either way if you have the ASM/TPIS large tube runners then you also have the small tube under the large outer tubes on both sides (you can see it on the pass side photo but not the drivers side) and the end of the detent cable where you adjust it does not fit between that small tube and the large runners, did you install yours by removing it at the trans and sliding it thru that way?
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Le Mans Master
Joined: Aug 2007
Posts: 8,735
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From: WV
If what your saying is the top end of the TV cable won't go through the runners then thats normal..I couldn't get my cable through either,the head is to big, you have to pull the plenum to do it..I don't see why you would ruin the gaskets just unbolting and lifting the plenum, as long as you didn't glue them in place..I have pulled my plenum a few times and just put it back in and retorqued it..Thats why the top runners are cut at an angle, so you can pull the plenum without having to loosen the runners or destroying the gaskets...WW
Last edited by WW7; Jul 19, 2010 at 08:40 PM.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
I'm leaning toward using silicone to "glue" the runner gaskets to the runners but leave them unglued to the base/plenum. OTOH, I like the idea of putting teflon, vaseline, anti-sieze, etc... on the other side to promote easier separation (with a bit of goo to fill any gaps).
Last edited by GREGGPENN; Jul 19, 2010 at 06:41 PM.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 413
From: WV
What I do is use the spray tack on the side that goes on the runners, and nothing on the plenum side..Then when you unbolt the plenum you can lift it straight up and the gaskets stay on the runners without tearing.Your only sealing against low pressure air flow so you really shouldn't need glue .WW
Last edited by WW7; Jul 19, 2010 at 08:43 PM.
