hey guys,

The car is running good now with the weber 45dcoe, althought I noticed that the carb was icing a bit (very very cold intake manifold, and it had condensation on it). Besides this the car seems like it isnt firing on all all plugs at the proper time and stumbles a small bit. Im wondering if this could be caused by my most likely fouled spark plugs. Im going to replace the spark plugs as soon as I can and hopefully get the car painted. I realize with the icing that the stock carb had the coolant passages in the lower intake manifold. Will icing create problems for me down the road? Is there any way i can eliminate it?

Thanks
Dan_s_young

 

some people wrap the intake manifold with exhaust heat wrap. but it kinda looks well.... gaudy (sp?) hahaha. but if it works do it.

 

If I got on mine hard, it used to actually create frost on the manifold in the fall/winter, lol. I never really worred about it since for the most part, it didnt do it.

~T.J.

 

mine just stopped doing it one day... i still dont know why

 

Oh, and the DLIDFIS system I built and installed cleared up a lot of the "stumbles" that mine had FYI.

~T.J.

 

what's your jetting? and what engine and porting?

 

sorry lol I should have clarified more. 12a stockport (for now).

170 mains
f-11 e-tubes
160 air corrector
36mm venturis
3 psi of fuel.

and im still curious as to why my fuel pressure gauge goes to zero psi after about 5 minutes of operation....

 

brand of fuel pump? Are you running a return on that carb? Any mods on the carb's fuel inlet?

 

I am using a carter fuel pump and a holley fuel pressure regulator.

I am not running a return and there are no mods to the carbs fuel inlet that I am aware of.

I almost think that the fuel pressure gauge I bought was designed to do this for some reason but I am not sure. It is a liquid filled 0-15 psi gauge from summitracing.com...

 

I've got the same fuel pressure gauge as you. Mine does the exact same thing, was quite baffling when I saw it first happen.

 

i reccomend running 4 psi. My thinking isit goes to 0 because you're draining the float bowl. I run 4 street and 5 psi racing. then again i'm a 13b. jets look good. make sure you run a 65f9 for your idle jet! maybe a 60f9, but nothing else will work correctly and WILL cause lean stumbles upon switching from the idle circut to main circut.

 

My Carter pump would do that to me on my 7 AND the one on my Toyota. It would run fine forever, then just randomly drop pressure. I could pull the line off the carb/regulator and apply vacuum and it would start pumping again just fine - for who knows how long. I had tried replacing everything else (even flushed the tank, replaced all lines, rebuilt the regulator, even tried taking the pump apart, etc), turned out to be a bad pump. I was using a no name pump on the Toyota (came with the truck) when it started on that one, which is why I went through all the fuss of replacing everything BUT the pump (the pump was new and barely used). But, after all that, I just had two bad pumps in a row. The RX-7 magically stopped doing it one day after I replaced all the rubber fuel lines. I was thinking it was creating air bubbles in the lines past a leak possibly, and causing it to loose it feed? I dont know, all I know is it just stopped one day, lol.

~T.J.

 

This is because you are not running a return line from your regulator; I used to have the same problem with my car, I used 4 1/2 PSI and the press drops after 5 -10 minutes of work, so I installed a return line and it works real good now.
I have a Holley Red Fuel Pump in my car.

The fuel line is installed with a 3/8 I.D. hose and it never gets air bubbles in it.

 

Everyone else who is running the same setup as me is not using a return line though...

 

I am using the same setup as you and I needed the return line.

It is very simple, if you don`t have the return line you will get 0 press readings, this does not means that the fuel press is in 0, it is setted at the desired fuel press you put in the regulator but you cannot make adjustments to the fuel press if you don`t know the exact press you are using at the exact moment.

Mine used to get 2 or 3 or 4 or 5 psi readings when the exact setup was 4 1/2psi so I get mad one day and got the fittings and return line on... Problem finished...

 

so for the return line you just utalized another of the FPR's outlets? I don't understand as to why you want to do this, most of the fuel return lines are from the carb when it is overfilling with fuel...

I can get accurate fuel pressure readings, it stays at a steady 3 psi but like I said it drops right away. I still almost think that this fuel pressure gauge is designed to do that??? And im wondering this will not cause any problems if I don't run a return line and just suck up the fact that the fuel pressure guage is at 0 psi after 5 minutes of operation.