Go Back   Rotary Car Club > Tech Discussion > RX-7 2nd Gen Specific (1986-92)

RX-7 2nd Gen Specific (1986-92) RX-7 1986-92 Discussion including performance modifications and technical support sections.

Reply
 
Thread Tools Display Modes
Old 09-30-2008, 03:39 PM   #1
stylEmon
Rotary Fanatic
 
stylEmon's Avatar
 
Join Date: Feb 2008
iTrader: (1)
Posts: 125
Rep Power: 17
stylEmon is on a distinguished road
Default Stock FPR Problems: Who else...

Has anyone had problems with the stock FPR? I am curious because I am having issues with Fuel Pressure. I have an new filter, new lines from filter to rails, stock rails, 1600cc Bocsh secondaries, no pulsation dampener and stock fpr. (Walbro Hi Flow pump)

I noticed pressure issues, and took off the stock fpr. Replaced it with another stock one and am having the same issue. It's possible that both fpr's are faulty. I would even say it's probable.

Anyone have any insight or similar problems?
Obviously I want to upgrade to an Aeromotive with braided lines and AN fittings, but I don't want to spend the $600 on that right now..
Thanks






stylEmon is offline   Reply With Quote
Old 09-30-2008, 06:04 PM   #2
Ender
rotors excite me
 
Ender's Avatar
 
Join Date: Mar 2008
Location: Iowa
iTrader: (3)
Posts: 372
Rep Power: 17
Ender is on a distinguished road
Default

I don't have any personal experience with something quite like your situation, but I suspect you could have fuel flow issues when two of your injectors are rated for ~3 times the flow of the stock injectors. Are you seeing the pressure drop under light load or just when you're under boost? More specifics would probably help.
__________________
He isn't a killer. He just wins -- thoroughly.


'87 TII
240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

Quote:
Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
360 gamertag: quick Tii
Ender is offline   Reply With Quote
Old 09-30-2008, 07:15 PM   #3
stylEmon
Rotary Fanatic
 
stylEmon's Avatar
 
Join Date: Feb 2008
iTrader: (1)
Posts: 125
Rep Power: 17
stylEmon is on a distinguished road
Default

not sure why that would be a problem. I have a stand alone.

The main problem is at idle. The fuel pressure is 20 psi higher than it should be. Under load it raises a little more.
stylEmon is offline   Reply With Quote
Old 10-01-2008, 07:35 AM   #4
classicauto
crash auto?fix auto
 
classicauto's Avatar
 
Join Date: Feb 2008
iTrader: (0)
Posts: 816
Rep Power: 17
classicauto is on a distinguished road
Default

Hmmm.

When did you first noticce the issue? Anything else changed/going on in that time period?
classicauto is offline   Reply With Quote
Old 10-01-2008, 03:26 PM   #5
TehMonkay
Rotary Fanatic
 
Join Date: Apr 2008
Location: Louisville, KY
iTrader: (0)
Posts: 302
Rep Power: 17
TehMonkay is on a distinguished road
Default

It's either not bypassing enough fuel or there's a clog in the line or your fuel tank is very pressurized.
__________________
My car blows up everytime I start it, it's rotary

TehMonkay is offline   Reply With Quote
Old 10-01-2008, 04:42 PM   #6
stylEmon
Rotary Fanatic
 
stylEmon's Avatar
 
Join Date: Feb 2008
iTrader: (1)
Posts: 125
Rep Power: 17
stylEmon is on a distinguished road
Default

I think its always been a problem since I had this car running after the engine build.
It was masked by other problems, or unfinished tuning... make sense?

So what causes the tank to be pressurized?
We are suspecting that my walbro is faulty... I dont want to have to buy another one (since they offer NO warranty on it) but this may be the culprit...
stylEmon is offline   Reply With Quote
Old 10-01-2008, 06:44 PM   #7
jgrewe
Rotary Fan in Training
 
Join Date: Feb 2008
Location: On the Beach
iTrader: (0)
Posts: 59
Rep Power: 17
jgrewe is on a distinguished road
Default

Take the top off of one of your stock FPR's and put an adjustable top that is made for a Honda on it. B&M makes them, they are about $50 from Summit racing.
__________________
New rat from the sinking ship.
jgrewe is offline   Reply With Quote
Old 10-02-2008, 07:50 AM   #8
classicauto
crash auto?fix auto
 
classicauto's Avatar
 
Join Date: Feb 2008
iTrader: (0)
Posts: 816
Rep Power: 17
classicauto is on a distinguished road
Default

Quote:
Originally Posted by stylEmon View Post
So what causes the tank to be pressurized?
Poor venting. Are you running a charcoal canister?
classicauto is offline   Reply With Quote
Old 10-02-2008, 08:48 AM   #9
stylEmon
Rotary Fanatic
 
stylEmon's Avatar
 
Join Date: Feb 2008
iTrader: (1)
Posts: 125
Rep Power: 17
stylEmon is on a distinguished road
Default

no...
stylEmon is offline   Reply With Quote
Old 10-02-2008, 02:51 PM   #10
TehMonkay
Rotary Fanatic
 
Join Date: Apr 2008
Location: Louisville, KY
iTrader: (0)
Posts: 302
Rep Power: 17
TehMonkay is on a distinguished road
Default

So, do you just have a cap on the line on the firewall going to it?
__________________
My car blows up everytime I start it, it's rotary

TehMonkay is offline   Reply With Quote
Old 10-02-2008, 03:45 PM   #11
stylEmon
Rotary Fanatic
 
stylEmon's Avatar
 
Join Date: Feb 2008
iTrader: (1)
Posts: 125
Rep Power: 17
stylEmon is on a distinguished road
Default

pretty sure its all capped... not positive. I'll have to check it out.
So high fuel pressure is a symptom of this? What other ill effects from running no canister? or capped off lines?
stylEmon is offline   Reply With Quote
Old 10-03-2008, 07:11 AM   #12
classicauto
crash auto?fix auto
 
classicauto's Avatar
 
Join Date: Feb 2008
iTrader: (0)
Posts: 816
Rep Power: 17
classicauto is on a distinguished road
Default

Capping the vent for the tank will do some things......I'm not sure if high fuel pressure would be one of them, although its ENTIRELY possible.

All that vent's doing is essentially what the "vent" hole on a gas can does. It allows air to replace the space occupied by fuel once you start suckign fuel out. Does the reverse when you start pouring fuel in.

Its vented through the charcoal canister to keep fumes down, other wise you'd probably smell fuel coming out of the hole.

I've seen gas tanks collapse inwards from a plugged vent + heavy duty fuel pump.
classicauto is offline   Reply With Quote
Old 10-03-2008, 09:02 AM   #13
stylEmon
Rotary Fanatic
 
stylEmon's Avatar
 
Join Date: Feb 2008
iTrader: (1)
Posts: 125
Rep Power: 17
stylEmon is on a distinguished road
Default

yikes. makes sense tho.
Will look into that.
stylEmon is offline   Reply With Quote
Old 10-12-2008, 10:31 AM   #14
stylEmon
Rotary Fanatic
 
stylEmon's Avatar
 
Join Date: Feb 2008
iTrader: (1)
Posts: 125
Rep Power: 17
stylEmon is on a distinguished road
Default

it is not capped off, so thats not a problem.
It is the fuel pump. I've been having issues with this pump for a while. Sometimes the pump would be really loud, other times not so loud... and it didn't matter what the fuel level was. I should've returned it months ago but now I am stuck buying another walbro!!
stylEmon is offline   Reply With Quote
Old 10-12-2008, 11:50 AM   #15
SpooledupRacing
Guest
 
Posts: n/a
Default

loud pump = bad pump.. sorry to hear looks like a new pump is in order.
  Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 08:14 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Hosted by www.GotPlacement.com
Ad Management by RedTyger