This may be a stupid question but is there only one 6mm VAC source? I ask because I believe I will be needing 3 for my Wastgate/boost controller and BOV. I tried to search for a Profec B Spec II install to answer this but I couldn't find one even though I swear I saw one once.

This is my first build so things are new to me. I assume my other option would be to use an expansion couple fitting to go from the 3.5mm to the 6mm line. Is this ok to do or would I not get proper readings from this?

Thanks,
Ryan

 

https://www.rx7club.com/showthread.p...t=vacuum+lines

 

Bumping this thread back up because I'm trying to figure out where to run my BOV's vacuum line to on the UIM. More specifically, Tial states to use 1/4" vacuum lines with their BOVs (I'm guessing a 6mm hose will be close enough?)

It seems like every vacuum nipple is the 3.5mm size, and the only 6mm goes to the catch tank/charcoal canister?

Are people resorting to welding on larger vacuum barbs into the UIM?

 

I ran my Tial 50mm to one of the outer nipples on the UIM. Synched it down with a zip tie and it has worked fine.

You could consider removing the small nipples, tapping the whole, and adding a larger barb or even better an fitting and AN line. A bit of work, but a bulletproof result.

 

Thanks, I assume there is no difference between using one of the 2 outer nipples on the UIM or one of the nipples under the UIM (near the throttle body)?

I'm planning on running my FPR's vacuum line to one of the 2 outer nipples so it's easily visible. For my BOV, I'd like to run it to one of the nipples underneath the UIM.

I was talking with a Tial representative and he noted that a lot of RX7 owners used lighter springs in their BOVs, I think due to the smaller nipples... did you have to adjust your BOV's spring by connecting the larger vacuum line onto the smaller nipple?


(this post may be a record-breaker for most use of the word nipple)

 

Lol.... Yes, the sources are the same.

On the spring, I started with a 12lb and it was simply too tight. I then moved to a 7lb per Tial's recmmendation. It was too light, as even with my SP engine, it pulls the BOV open at idle. I recommend a 9lb spring for the Tial 50mm. It will be the right balance.