Boost gauge install...I know what you are thinking, but read on.
 

Before you start...There were no instructions included. I searched the archive and also looked at the big sites before this post. I'm sick, my car is sick, frustrated and need help.

So help a Rotory Brother.

http://7sins.rx7life.com/gaugeweb.jpg

Also...what adapter do I need to go from the small supplied hose to the manifold nipple?

What grommet should try to enter in the firewall?

If you want to do it right you need to use all of those pieces, except for the one in the upper right corner, I don't know what the hell that thing is for. The grommet is for the hole that you drill in the firewall to rout the hose. Some people have found alternate routing methods like the steering rod boot, or behind the plastic fender liner. Attached is a pic I threw together showing how to do it right. Sorry for the crappy Photoshop writing:

Let me explain that picture a little better. Basically you need to buy an NPT (national pipe thread) coupler and NPT nipple. You connect the 2nd pressure fitting that you already have to the other end of the nylon tubing, then screw the pressure fitting into the coupler, and the nipple into the other end of the coupler. Make sure to use pipe thread tape on the threads to ensure an airtight seal. Then you connect a rubber or silicone hose to the nipple and route that to the extra nipple on intake manifold. You can get the coupler, nipple, and tape at Home Depot's plumbing department. Bring along the pressure fitting and silicone/rubber hose so you can size them up.

I think the manifold nipple is 6mm...right?
So I need some 6mm hose and a 6mm nipple to go to the coupler?

No I think it's the 4mm, but I'd have to go check to be sure. Anyone else know for sure? The nipples are sold in SAE sizes (1/4", 5/16", etc), I think a 1/4" fits best, but bring the hose along to be sure.

I assume we always refer to the inner diameter.

You assume correctly, I (and a few others) actually used 3.5mm hoses for all the 4mm stuff. It's a little tougher to get on, but once it's on it's not going anywhere.

Admins/Mods - This might be a good thread to throw in the archive since it gets asked a lot.

Boost gauge install...I know what you are thinking, but read on.
 

The adapter in the upper right is to 1/8" to 1/4" adapter for the pressure fitting, fairly worthless. At one point I ended up having 2 or 3 different adapters to go the larger type hose (I used 5/32" radiator hose until I do my silicon upgrade.) Though after that I found a 1/8" to 1/8" NPT to barb type coupler. I noticed that PFS recommends to place the adapter as close to the manafold as possible, possible due to the change of hose sizes affecting the readings (just a far off guess..really.) I've heard problems with it not zeroing out correctly, but so far I havn't had any problems..

I got that same stuff with my autometer. I set up the hose and the fitting according to the diagram that it came with and the nylon hose can just be pulled out of the fitting. Is it suppost to be like that?

No, not at all. Did you slip the little metal o-ring thingy over the nylon tube before tightening it into the fitting? That o-ring crushes up against the main fitting and locks the tube in place.

Mine is installed, but not without irritation. I doubt my nylon tube will slip, but the brass fittings for the other end are a waste.

The fittings only turn about 2-3 times. I tefloned them and tightened them as much as I could on the gauge. Seems it should turn more.

On the other end, I crammed the nylon tube into a rubber connector from AutoZone (Vac-Tite part #47400). It's a 7/64"x1/8" connector. I glued the nylon tube a few mm from the end and Zip tied it. The other end is tight as a tick's ass over the manifold nipple, but it goes on and I don't think it will slip off. I put a tiny hose clamp there for extra measure.

Oh I see. I wasn't installing it, I was jsut putting it together to see how everything goes together and I didn't tighten it down very much. My RE boost gauge dosn't have all this threading stuff. Just a nipple for a vac line.

Thanks

i had the same setup u did in the beginning, but i just took off that rounded off cap that has the hole for the plastic turbing and just connected the remaing nipple and the plastic stubing with a vacuum hose. this way i dont' have to worry about leaks. But i'm not sure if this way will affect readings.

hm. I have the same diameter silicon vacuum tubing from the manifold, thru the FW, and up to the Autometer boost guage. Fits tight as a glove. What's with the pressure fittings and diameter resizing? Just a different setup, or is mine a hack job?

My gauge has a male threaded fitting on the back.So I had to use a female connector with the pressure fitting to connect the nylon tube.