A few carbernator setting questions ;)

Cordoba1

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It won't be the bowls draining back to the tank. The needle and seat are at the top of the bowl. Cannot physically do that once fuel is below the needle and seat. I have seen however, many small cracks on float bowls that would eventually empty the bowl. And if a carb could be"so well set-up" that it didn't need a choke at start-up, something is compromised. All internal cumbustion engines need fuel enrichment on cold startup, even e.f.i.

Oh geeze, that's right! Leaky carb internals? I've know I've had this issue when the bowl isn't full upon startup.
 

8v-of-fury

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Albeit that is a damn good plan! There isn't anything older than 2000 in ANY junkyard anywhere near me. Let alone the cop spec'd M-bodies.

That is basically a stock 360-4v with a cam? 335/400? that's pretty dang badass! I wish I could do such a swap so dirt cheap. It'd be easier to build this teen. Definitely the easiest way to do it for bang/buck.
 

BudW

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at that point it will chug way down to about 500rpm for about 2 seconds and then it will rise back up to the high idle.
This (still) sounds like to me the fuel bowl is empty (not the accelerator pump circuit) and it takes a second or two for fuel pump to refill the bowl.

The accelerator pump circuit uses check balls and weights to keep that system air tight (so to speak) so you generally will have 2 to 4 pumps before that circuit go dry – if bowl is dry.

A couple of ways to test (unfortunately there is no easy way).
1 - Keep cycling the throttle and watching the pump spray. If you got 4 shots then no additional good sprays (then bowl is empty). If fuel bowl is full, then you will have roughly 50+ shots until empty.
Be sure to leave throttle valve open a bit, because 4 or more shots can/will flood the engine.

2- remove carburetor and turn upside down over a container that you can use to measure how much fuel is inside it on a ready to use cold start engine.

3 - Remove the carburetor mounting bolts and choke clip. Insert cardboard under the cold start carburetor and check how many full squirts you can get (doesn’t flood the engine that way - but still messy).

4 - remove carburetor top (on engine or off) and see if enough fuel is inside to keep float up against the needle and seat. Sense float is attached to top – and no longer in the bowl, I would guess the remaining fuel would be ½ to 2/5th full. If much less than that, then you have a problem.

BudW
 

8v-of-fury

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Here ya go! A video showing what I mean, I do not believe the bowl to be draining down. I tried this morning to do no pump and no choke set. It didn't even try and fire. I had to give it two pumps, and then two pumps again when it didn't fire on the first two. Tomorrow morning I'll see what just two full pumps does.

 

6thGenImperial

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Albeit that is a damn good plan! There isn't anything older than 2000 in ANY junkyard anywhere near me. Let alone the cop spec'd M-bodies.

That is basically a stock 360-4v with a cam? 335/400? that's pretty dang badass! I wish I could do such a swap so dirt cheap. It'd be easier to build this teen. Definitely the easiest way to do it for bang/buck.
Yeah, pretty much. Remember he had to make an attempt to retain emissions. There's a lotta HP available if you can ditch those cats. On the 318 they added 100hp with just a 4V induction and CC's XE262H cam (final number was 282hp at 5000 with 340ft/lb at 3600). That's with stock small valve heads. Naturally, there's the 400HP 318 Junkyard Jewel, that steps up the cam a bit and adds 360 heads with big 2.02 intake valves. The 318/360's always had such mild cams, they really wake up with a decent aftermarket stick.
 

8v-of-fury

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I could very likely ditch them, and either run a gutted one or a high flow single unit. I think headers to like 2.5 and a crossover to that single cat, and then a 3" cat back? Or would it be worth all that hassle to move the tank over, and run duals ? I'd need two cats then. which is getting expensive! LOL

I think I seen some articles that use the stock manifolds, but then the "canadian" or catless y-pipe and still make the good power. So I'd more than likely go that route and run through a single high flow cat/muffler. I'd also love to be ballsy and run that through the stock 904 and 7.25 for the time being! Just to see how long it could really last ;) It won't ever see neutral drops.. or drag racing or anything other than the spirited driving.

I thought that 400hp JY jewel one used aluminum heads? Also an option by the way.. as it would most certainly be worth the coin. The heads/cam would bolt on basically an easy 200hp. I already have the 4v setup, so i'd just need exhaust after that.
 

6thGenImperial

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Nah, the Jewel used stock 318 heads all hogged out to max size (essentially ported 360 dimensions) with 2.02/1.60 valves.
318 Small Block Build - How To - Hot Rod Magazine
With any high performance setup, I think the best compromise would be the 2.5/3 inch setup you mentioned. I think I'd go with a slightly milder cam and trade off some of the top-end for a fuller torque curve below 3,000rpm in a heavy street car. Otherwise, with that setup, definitely go for some gears and a looser converter.
 
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