1rx7owner

Sorry about the poor quality its not a very good camera. My question is....when the engine gets to about 3000 rpms and I hold it there after about 30 seconds the engine starts to spit and sputter like it wants to die until i put a throttle into it. After I rev it up just about 300 or 400 rpms it starts to run better. But if I let it go back to 3000 and hold it there it starts to run like crap again. Anybody know what they think the problem might be? I have a 12a streetported with a 48dcoe weber.

REVHED

Does it do this when reving the engine at idle or when driving around? If it's only at idle then I wouldn't worry about it but it can definately get annoying if it constantly sputters around when trying to drive the damn thing. I know from experience.

To me it sounds like your running too rich on light throttle/light load. This could be caused by the idle jets being too big, too much fuel pressure, float level too high or a combination of these things. What are your specs at the moment?

1rx7owner

it does it while I am driving around. It does annoy me cause I have to keep speeding up and slowing down. I dont know the specs at this moment but will get them soon. I was thinking it was something to do with the gas also.

REVHED

Yeah, definately sounds like you're rich on light throttle... had the exact same problem with my IDA. First of all make sure the float level is correct and fuel pressure is set at 4.5psi. Then try adjusting the mixture screws... turn the screws in clockwise till the rpm's start to drop and then back out 1/4 of a turn. If it still stumbles I'd maybe try going down one size on the idle jets.

WackyRotary

it doesn't even have a regulator it looks like in the pic. You NEED to have one you know. It will run like crap you if don't. Don't get one of those stupid puralator style ones. They are not accurate and don't flow enough to keep pressure steady since its too small.

That was my two cents.

Directfreak

iTrader: (2)

Gotta love simplicity..(nice engine compartment)

You said it might have to do with the gas..
Is your fuel tank contaminated or are you using cheap gas? Elaborate.

I believe rotaries in general a little stutter now and then. Make sure there's no crap in the carb jets.

SilverRocket

Is that your brake booster line hanging there like that? You should hook that up.

And yes, you need a good fuel pump (ie. Carter 7psi, Holley blue, etc.) and a regulator. The Holley 4.5-9 psi regulator is fine, and cheap too. Excess fuel pressure could well be your problem here - if I turn my fuel pressure up past 5psi on my regulator (and Carter pump), my Dellorto acts like that too.

85RX7GS

iTrader: (1)

Fuel pump or fuel filter, possibly...

1rx7owner

tell me where can I get one of those holley fuel pumps and regulators. I have looked all over and cant seem to find one. And no there is no regulator on that, it is a stock fuel pump and was told that it would work fine with the carb. Yes that is the brake booster line hanging down and right now I have no power brakes but it is not hard to stop. thanks for all your comments. I also did try to keep the engine bay simple and I have a bunch of wires to get rid of as you can see with all the coneectors laying all over the top of the engine.

SilverRocket

Blaaaaa... no it definitely won't work fine with that carb and a streetport!!

The cheapest and more than adequate choice is the Carter 6-8 psi street/race fuel pump. You can purchase this from summitracing.com or just about any automotive speedshop. The Holley regulator is the 4.5-9 psi model, and can be purchased at the same places.

BTW, the brake booster line should be hooked up in case you stall while braking on the road, ie. in an emergency. If that line isn't hooked up, your ability to stop will go away in short order. Not too safe! If you can find a way to hook that up, you should.

The connectors can be hidden by sliding them over the transmission tunnel out of the way. It's not too smart to cut them in case you ever need to reconnect them for some reason.

1rx7owner

Thanks for the advice, I will try and get those things as soon as I can. So do you think if that doesnt work that my jets in the carb are too big. This car has been such a money pit but I think soon everything will be all worked out. I just cant wait to see what kind of power it makes, have been taking it real easy on the rebuilt motor since it has only about 100 miles on it but iy does feel good. The brake booster line will be hooked up soon too. Thanks.