I was wondering if there's any adverse effects if I were to run the 89 and newer style tpi runners with an 88 and older style plenum. I'm not running the ninth injector, so that's not an issue. I'm just wondering if there would be any vacuum issues by using the newer runners with the older plenum? Thanks guys.

 

I believe the EGR/IAC passages on the early style will be a major problem (leak) on a newer base, or vice-versa. IIRC, the later style lacks the tube and boss at the base for the tube to join.

 

On my Girlfriends TPI car. We have an 85 Passenger side runner, 91 Driver side and an 89 Base and Plenum. It all fits perfect.

 

Oh yeah, that combination I do know will work for sure. Through my research, I've read that the passenger side runners are identical for all years of tpi, and the rest of your girlfriend's setup is all the newer stuff. Vader, my issue isn't at the base as I have an 89 and newer base, and also a set of 89 and newer runners. I was trying to figure out if those runners and base would work with the 88 and older plenum. I know that passage on the underside of the plenum that runs to the drivers side runners would be blocked off, and that's what I'm wondering is if it would affect anything that you have to have vacuum for. Whatever the case, I have all the parts for the 89 and newer setup except for a throttle body, which I just made a deal on one, so I'll be good to go anyways once it arrives. I guess I'm still seeking an answer to this question out of sheer curiousity at this point! If anyone knows the answer to this query, I'd love to know, because no matter how many tpi sites I've been to, none of them address this issue. You know how it drives you crazy when you can't find an answer to something stupid. Btw, once I get the newer setup all put together, anyone interested in a good deal on a complete 85-88 setup?