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Discussion Starter · #1 ·
I am currently trying a DUI distributer. The increase in low end torque is great, but starting after it has sat for at least 4 hours takes a while. EFI not carbed. What do I need to check. A "friend" of mine set the timing, but I don't think that's the problemb. She Idles smooth as silk for a change. It is almost like it is strugling to pick up fuel after it sits. Hope that I havent left anything out.

88, 302, EFI, DUI distributer, Jet chip, K&N filter
 

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Sorry I side track so much, but you said your DUI distributer is great for low end torque. Did it increase it when you installed the sucker, or are you just saying that it compliments something else you're using? I'm asking because my 302 acts like a worn out 4cyl. until about 2100-2400 rpm. After I added my dual exhaust, the low end dropped out and I've been looking for something to increase it ever since. So how noticeable was it? Thanks, and sorry again for the side track.
 
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Discussion Starter · #5 ·
From the time I installed it. It's not going to throw you back into the cargo area, but you can definately "feel" the difference. They are a little pricy, and currently I am trying to justify the 400 bucks, but I have picked up more "power" from this bolt on than from any other. My old factory distributer was pretty much worn out, as well as the smaller plug wires. The points were pretty much goners too. You lost your low end when you installed the duals? I am getting ready to put in headers and straight pipes (no regs on off road use only vehicles. At least we tell him that it is off road use only
) What kind of system did you put in? I still want to do the 460 swap, but have got to save up some more fun tickets! A buddy of mine knows someone... who knows someone... that says that he can get a dyno engine from ford for 500 bucks plus shipping (about 200 bucks). Sounds like a good deal to me! (complete engine, carbed or injected, less manifolds) Supposedly, these engines are run for 24hours at 4000rpms. The only problemb so far is that he won't drive up there for one engine, so I am trying to be patient, and wait for his next trip. Currently this is all heresay, but the more that I look into it the truer it becomes.
 

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I took mine to a muffler shop and pretty much let him have his way with it. He suggested a complete dual system: 2-1/2" tubing all the way back, 2 hi-flow cats (he wont touch a truck that doesn't have cats), 2 turbo mufflers, 2 2-1/2" x 15" chrome tips (which he threw in), all for $350. Don't know model #'s or anything on the mufflers or cats. What I told ya is what I know. Not very loud (louder than stock), but man does it sound MEAN!!!! Gave me lots of high end, but as I said dropped the low end, I guess the loss in back pressure did it for me.
 

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It's a pipe running between the duals.
Usually close to where they make the turn to horizontal from the header exits.
Your exhaust would look like an H where the crossover would be.
If I can find an old article that explains where it should be placed, I'll let ya know.
Really will help get some of the bottom end torque back.
All street run vehicles with true duals should have one.

This is the best I can find right now.
"H- and X-tubes for dual exhaust--
H-tubes balance the backpressure between the two sides of your engine, and even out the complex pressure waves that are flying around in the pipes. The result is enhanced low-end torque, better overall performance, and better sound.
X-pipes do a better job of this than H-pipes, because there is no distance separating the pipes with an X. But some cars, like my 'Bird, have no way to fit an X underneath.
H-tubes should be at least 3/4 the size of your exhaust pipes, and located in the "hot" area of the pipes behind the header outlets. To find that hot area, one suggestion is to spray a line of ordinary white paint down the pipes after the headers, and go for a good run. Install the H-pipe somewhere in the area where the paint burns off the pipes, equal distance from each header collector. Use the same technique to determine where to place an X-pipe."
 

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Re: H-pipe?

I do have a small pipe (3/4" roughly) that runs between the two near the front. It has some sort of sensor in it. Is that what you're talking about? Is the DUI distributer kinda like a jacobs ignition system? I was looking into that. Guesstimate how much hp you got out of it for me please. 10, 20, 5, or what? I estimate about 50-60 hp difference from stock from to now with all I added, but you wouldn't know it by me taking off at a stop light until about 20mph. I got no chance at chirping the tires, I don't even think with hubs locked out in 4-lo! When I got the thing it would throw me back into my seat, but slowly it has gone to high end. The thing is gutless now. I'm wondering if maybe the dealership put some sort of additive in the gas, or SOMETHING. If it is an additive I would sure like to know what it is cuz super octane boost (96+ avg. octane) aint doing the trick.
 

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Re: H-pipe?

That would be the pipe for your O2 sensor.
Kinda small for a crossover.
Should be 3/4 (75%) diameter of the exhaust pipe.
I edited my previous post.
Explained there.

I'm not running an H pipe.
Just know you should.
I've got a single 3" inlet, dual 2.5" outlet. (no cat)
If you really want to read more, go here.
Or, search for exhaust.
Lots of discussion lately.
 

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Re: H-pipe?

could you explain the x-pipe a little better/different? I'm kinda fuzzy here. The H-pipe/02 sensor may be a little bigger, but not 3/4 the diameter. Will the h-pipe or x-pipe have a NOTICEABLE increase in torque (how much)?
 

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Re: H-pipe?

its a definate "WILL-DO", though if its what i'm imagining, I don't see why I won't have room for an xpipe. BTW, is bigger better in this case (i.e. 100% of the diameter better than 75%)
 

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Re: H-pipe?

Back on the subject of hard starting.Check your fuel pressure at the schrader valve on the fuel rail.Turn the key on(don't start it) and listen for the fuel pump to kick on.The pressure should build up quickly to normal(35-40#).Turn the key off and watch the gauge.The fuel pressure should stay up for several minutes and bleed off slowly over time.There is a check valve in the pump that can be leaking,or the injectors or fuel pressure regulator could be leaking.Notice how long it takes the fuel pressure to come up when you turn the key on.Start the engine and watch the pressure come up.If it takes longer than a few seconds to come up to normal you might have a plugged filter.

Billy
 
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