Also I was playing with the carb.. My fuel sites were high. Adjusted down the primary. The secondary was empty. Corrected that. No fuel coming from secondary if i rev the throttle and manually open the vacuum secondary.

Will go get 6 plugs in a bit.

 

does the carb require both bowls to be fed with a line? Or the secondary bowl has fuel but you don't see any entering the stream? You may not see any because they are vacuum operated, someone will have to confirm.

Make sure the base plate is installed correct , you did its a cone shape one so it would wreak havoc if on wrong.

assuming your timing is correct I'd say its a carb issue if your plugs are black. You'll probably smell how rich the exhaust is by the sounds of it.

 

Are the cones suppose to close towards the carb or towards the intake?

 

Hit rod magazine has an article, they have the pointed side down.
​​​​​​www.hotrod.com/articles/slick-built-small-block-part-3/amp/

 

Got to ask what intake, adapter and carb are you using?
Got pictures of the set up?


How do you think the air would flow better with that adaptor??
It has to go on so the flow is not held back. I have only seen it with the large size to the carb if it is the one I am thinking of.


BTW: if the primary side bowl fuel level was too high it will make it run rich. Same for the secondary side too so make sure both are set right before you change jets.
BTW II: Jets only change the high speed side of the fuel system and has nothing to do with the idle side running rich. Bowl level will on the idle side so do the above first.
Dave ----

 

 

adapter is a transadapt plate I drilled to seat ont the clifford 6:8 intake. Inbetween plate amd carb is the included heat gasket from summit. Carb is summit 600 street strip

 

First, I think you have a really nice setup. I'm sure you'll enjoy it for many years.

Clifford manifolds are made to have the carb sit lengthwise, with the primaries facing the radiator. Cliff makes a bolt on adaptor. You have the older intake, hence the need for the exhaust heat plate. That's pretty cool, by the way.

I have run two Summit 600 carbs on my engine. I also have headers and found that with the long primary bowl over by the head (with a dp intake) as you have it, I started getting a problem during summer. Due to heat, fuel boiling out of the bowl, it became difficult to start.

I tried a heat shield and still it happened. Eventually I switched to a Holley and the prob. vanished.

You won't be able to get your secondaries to squirt sitting in the driveway.

*With our engines you don't need the thick Summit gasket. It is that thick to raise the carb so the acc.pump housing doesn't hit on the intake manifold of a v8/v6. But, since you have that exhaust heat plumbed to your intake, I'm thinking the thick gasket might help with heat transfer. How hot is your carb getting?

Good luck.

BTW, can you manually open your throttle full? You'll be living dangerously with that single spring on the throttle return. If that dude pops and it floors the gas, you're going hit max rpm before you can pull over. Go to autozone and get the double throttle spring.

Just clean the plugs, don't buy new. I'm not trying to nitpick your engine to death, just possible point out something that may cause a problem, ie you need longer stud(s). That one in the photo the nut is only grabbing a couple of threads. Vacuum leak? When you put on the fuel line to the Summit steel attachment, did that teflon tape wrap over the last thread? If it did, there's a good chance it is now in your carb.

 

And nitpicking doesn't bother me. I am just looking for my dang gremlin. I want it running. Not Rusting.

 

I think you're supposed to order a 2 or 4 barrel adapter from Clifford to install on the intake. If you made your own could there be a vacuum leak?

 

Clifford sells on. But mine seems to be working. I hosed starter fluid around it. Didnt act like a leak.

 

I know the feeling. There is nothing more annoying that not being able to find the ... problem. You'll get it. You're just going through a series of eliminations to determine what the issue is. Right now it seems as though it is the carb.

Just leave the carb as is. If the heat issue comes up, deal with it then. If you had a v. leak the idle would increase the instant you sprayed. You want to lean out the mix at idle. I'd put your test gauges on it and begin to open the mix screws 1/8 turn at a time; first one, then the other, and wait to see what affect that has on the idle. When you begin to approach lean you'll hear/feel the idle increase. You want it on the edge of lean. Turning the mix screws c.clockwise allows more fuel into the mix. And that richens the mix.

So set the mix screws for the original position--usually about 1 1/2 turns out from all the way in. Then begin to open them, c.clockwise, 1/4 or 1/8 turn at a time. If you turn one, you turn the other. Write it down if you need to.

Forgot to mention: Teflon tape. I do it to, but never let the tape cross over the last thread on the end of the fitting that first gets screwed in. See, the tape fills the voids between the high points, and if it crosses that last high point/thread, it gets cut off and washed into the carb. If you can't get that carb to run right, you'll have to open the top go from there. It's easy.

Just relax and feel the engine. Make an adjustment and wait and feel how the engine responds. Find that spot where the idle increases just a bit. If the engine begins to surge you've got it too lean. Back up a bit.

If you mess up, no biggie. Just begin over. Reset the screws where they were. You want to get to the place where you can feel that your incremental turns are having an affect. When it increases in idle, reset the timing. Advance it (counter-clockwise) until you feel it increase in idle again. Then hook up the v.advance hose and drive it. Take a 1/2" open end with you. If it pings, bump the timing 1/8" clockwise (retard).

Leave your jets alone until you get the idle right and are driving it.

*The throttle spring I mentioned has one inside the other. If one breaks, there is a back up so you don't have a nuclear melt down of your engine.

P.S. I hate buying from Clifford. He is way expensive. You should take some more photos of that exh. heat exhange and post in the thread at the top of the forum about running coolant through the intake. I'm sure a lot of members would like to see that. I've only seen one other intake done that way. And that was a Chebby, so it don't count. Good luck.

Kevin.

 

I have a friend coming to look at her tomorrow. Hopefully his expertise will point us closer to a real answer.

I also am going to just let her sit until I swap jets to the base Holly recommends. 1 per 2000ft. Just to be safe.

Are you talking about the sticky? I will get some tomorrow of this specifically.

 

Idle mixture screws control fuel, not air. Clockwise leans out the AFR. Is the Summit carburetor different?

 

OMGosh, did I write that? Ah! Thanks for catching that. I'm going to chalk that up to multi-tasking while writing, and editing w/o rereading.

Nope, the Summit carb is the same as all others. All you're doing is putting more/less fuel into the air flowing through the carb, thereby altering the a/f mix at idle.