Well, after one year of owning my seven I finally scraped up the cash to invest into a new exhuast system. I choose the RB system, didn't want the car to be too loud, getting old I guess, and you guys had good thing to say about it.

After removing which seemed like 300lbs stock system, the RB header, pre silencer and power pluse muffler bolted up as RB said it would.

Then I realized, this was it, time to fire the seven up with the new header, I have been waiting months for this very moment. I lowered the car and started it up. what?.... that doesn't sound right???? RPM's are at 2,200 at idle, car is spitting and sputtering, the fumes where buring my eyeballs.

Rotories do not like vacuum leaks!

This is where I went wrong - The RB instructions say to use the stock green mazda gasket on the back side of the meter valve, which was removed with the thermal reactor. In place of the meter valve RB ships a plate to cover the intake holes. Do not use the stock gasket, put a thin layer of high temp gasket sealer around the ports on the motor side and the back of the plate. Secure the plate with the 3 bolts that are supplied.

That was it. Started back up and she ran like a dream.


QUESTION: I have a vacuum line not connected to anything on the passenger side. It's a small line tee'ed off of the brake booster main vac line. The line was like that when I purchaed the car, does anyone know anything about this line?




Test drive. I can honestly say I noticed a power differnece right from the start. the car felt lighter and had more pull. The second gear chirp lasted longer as well.

I just ordered a new set of wheels. I have done alot of research and decided to go with the Konig 4x110 15x7 wheels. Next step is the Sterling Nikki carb.......

 

Congrats on your success!

The stock green (& very thick) gasket from the ACV will work, unless it has become warped over time; they tend to deform around the check valve from exhaust gas heat, & not be flat anymore. So long as the block-off plate is sealed well to the manifold, you're good. Re-check those bolts a couple times after running the car; they have a tendency to work loose from heat & vibration.


On a stock SA there shouldn't be anything tee'd off the brake booster line; IIRC it runs straight from the intake manifold banjo, through the mystery hose, into the hardline that crosses the firewall, and then into the booster via the one-way valve. Sounds like a PO mod.

 

Ah - more motivation to pull my RB system out of the shed and get 'er on! Thanks for sharing trials and tribulations. DD, nice to know a new ACV gasket will do, since I planned to replace all relevant ones on the install....

Pitch - if your Sa is the red one on your avatar, looks beaut! Another Sunrise Red in the fold!

Stu Aull
80 GS (sunrise Red)
Alaska

 

Thanks for your replies, not sure what the vac line is for but the car idles way down when I plug it. Seems to run better with it open. So are you saying since the vac line should not be there I should plug the line and readjust the car?


Yes my 7 is a red beauty. Purchased last year from a one owner lady that keep the car in the garage for most of it's life. It's a gem for sure and I feel lucky to have it.

 

What does the other end of it go to? Is it just hanging open? If so, you've basically got a permanent moderate vacuum leak that your idle has been adjusted to compensate for. When you plug the "leak," idle drops because you've got a richer mix/less airflow that you otherwise should have.

Might be worthwhile to figure out why it's there, and what it was supposed to be doing. Got any pix?

 

The open vac line is tee'd off of the brake booster vac line. looks like someone cut into the main brake booster line to install a tee. Line is connected to the tee and is not connected to anything.

 

Couple things I fogot to mention. You will need to cap the intake ports on the stock air box so your not sucking unfiltered air.

I found a matching blue plug and secured it with high temp silicone to cover the main air pump line and a rubber seal to plug the other.


The header looks good, hard to keep clean but a much cleaner look.

 

Some pics for ya.

 

So the color is called sunrise red? Good to know. Yes, I like the red. Many years ago I had an 85 in red and an 83 in gray. Like the red the best. I have a front spolier that I plan to put on my 79, also have a Maria Motorsports whale tail that would looks cool but I'm not sure I want to drill holes in my car to mount it.
Thanks for looking.