I received my Marren fuel pulsation dampner in the mail today. I was expecting there to be an in and an out on it. Instead there was a single 3/8" port on the bottom and an air valve similar to tire valve stem on the side. Am I suppose to put a T into the 3/8" port and run it inline? And also what is up with the valve stem. I am using this on my 20b because i'm no longer using the stock rails. Thanks.

-Destin

 

Is it really necessary to run a pulsation dampner? I guess I never have. Please enlighten me.

 

Well stock they have them. I did a search on the forum and found some usefull information. I don't have any experience not running one and from what I read I don't want to destroy my motor finding if I need one or not.

Power Hungry, You don't run one? How long have you not run one or whats your experience with them?


-Destin

 

Yes run it into a tee fitting, anywhere on the pressure side of the system. I helped a friend install one, from marren actually. Its main purpose is for protection of fuel lines and injectors from damaging pressure waves every time the injectors open and close. Like Sillbeer said, they are on all stock Rx-7's , and is needed if using aftermarket rails.

 

Ive never used one. I dont have my car up and running but I never had a problem with eliminating it on my supra, but it never hurts to be safe. Out of curiosity how many people run the dampner?

 

I dont know how many use one, its more of a concern with larger, fewer number of injectors.

 

This subject has been bashed in the FC section, cause I abhor those things!

If you run an SX FPR, they explicitly state it is not necessary.


-Ted

 

yes, that is because the sx FPR has it built in. . . beat me to it, ted.

 

It's actually a little bit more involved than that.
ANY FPR is a PD with a bleed valve on it.
So, the FPR itself acts as a PD.
It's not that the SX unit is the only on "built in" - all FPR's are inherently PD's by design.


-Ted

 

I did not know that. Thanks Ted.

 

So basically, as I read this, mazda used a seperate FPR and PD, with the FPR only allowing fuel in at a set psi and the PD releasing the excess pressure?

 

FPR bypasses excessive pressure.
The fuel pressure in the fuel rails are fluctuating due to the pulsations from the fuel pump and the fuel injectors opening and closing.
The PD does not "release" anything - it just "damps" the fluctuations.


-Ted