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Jimmy B. ( parts from Bruiser)

Using a proven wheeling truck with another driving truck, plus more parts.
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I was looking at the 4 barrel style. So not the XT (?) .
I found posts about people who had bad experiences with FAST systems today. It all makes me think that I should work with this factory stuff more in order to help reliability.. like bigger throttle body, and an ECM modification from Dynamic EFI.
But I also found another person saying that a dual plane intake is not good for TBI. I found a thread in the injection section from AJ about what he is trying with his big block by swapping to a single plane manifold.
If Holley would have gotten @mrk5 his ECM back to him quickly and low cost, being out of warranty, I would probably just buy a Sniper. But I haven't seen where he has it back yet.
 
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skunked said:
Holley and their technical support staff can suck it.
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And I know that you had a problem with them back when, and have had good results with Fitech. I still am unsure of if I would be able to trust one of theirs .
My thoughts are that I should have done an 8.1 swap if it gave me power and reliability. But it's kinda late now!
I did find a thread where a guy was very pleased with the effort by Edelbrock with trying to fix a Proflo 2 system. This was over 3 years ago. They now have #4.
 
Having the 700R4 would make me look more at a system where I didn't have to spend more time and money on a new TV cable and throttle cable.

I really wonder if the air velocity is changed significantly at part throttle, with these heads and headers, to make this thing throw such a fit. Could a single plane intake help it???
I don't know unless I buck up and pay the money.
 
Stock TBI intakes are essentially a dual plane in the first place. Granted they are a bit more restrictive than the aftermarket stuff. I'm not that experienced on the TBI systems to see how that would pose a huge change that the ECM would freak out over it. I just remember TBI spacers to be the hot ticket to add a few more ponies to the stock system by adding plenum volume which an aftermarket dual plane intake would be doing in the first place.
 
beags86 said:
A good fix for a 700r4 is a third pedal.
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Yeah, yeah...
I still have the NV4500 truck, and probably more miles with a manual trans than you and @Bent77 combined!

@ZooMad75 , my wonderment is if the dual plane intake , throttle body spacer AND the new heads and headers have added up to a combination that is giving problems at part throttle conditions.
I have been thinking about what my next change is in chasing this problem. I will have to try some different things with the timing, and possibly fuel pressure. I have a NIB vacuum reference fuel pressure regulator that I may try too. Maybe that would help clean up the idle, if I need to crank the pressure up.
 
6872xtc said:
Yeah, yeah...
I still have the NV4500 truck, and probably more miles with a manual trans than you and @Bent77 combined!

@ZooMad75 , my wonderment is if the dual plane intake , throttle body spacer AND the new heads and headers have added up to a combination that is giving problems at part throttle conditions.
I have been thinking about what my next change is in chasing this problem. I will have to try some different things with the timing, and possibly fuel pressure. I have a NIB vacuum reference fuel pressure regulator that I may try too. Maybe that would help clean up the idle, if I need to crank the pressure up.
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I think you are on to something. With the combo of better parts over stock you can move more air than what the TBI system was designed for. Since its a speed density system the calibrations are based on the stock parts by changing to more efficient parts you've thrown the stock calibration tables out the window.

Put another way, the stock setup sees the engine at a specific rpm with x amount of baro signal from the map sensor it should deliver a specific amount of fuel by controlling the injector duty cycle. But if you are flowing more air at the same rpm, the amount of fuel at that point may not be enough. Increasing fuel pressure is the quick and dirty way to deliver more fuel, but a custom tune would be the way to go.
 
Yes, that is what I was thinking. It does have a Howell chip in it that was in the '72. The engine had this intake on it with an adapter plus a spacer. It had stock '72 heads, milled some for compression, and rams horn style exhaust.
So the problem is that it stumbles badly when trying to just drive it. It does decent until just before closed loop, and then continues in closed loop.
 
6872xtc said:
Yes, that is what I was thinking. It does have a Howell chip in it that was in the '72. The engine had this intake on it with an adapter plus a spacer. It had stock '72 heads, milled some for compression, and rams horn style exhaust.
So the problem is that it stumbles badly when trying to just drive it. It does decent until just before closed loop, and then continues in closed loop.
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Sounds like you need to do some data logging. Talk to the guys at Howell about the combo and see what they would need to help tweak the tune. Larry has dealt with a similar issue on his father in laws 93 sportside he swapped a 454 into and is still running the TBI on it. Howell worked with him to dial it in.

Here's an idea though. If you can bump the fuel pressure 1-2 psi up from where you have it. If it cleans up on the part throttle stuff you can safely say it's not getting enough fuel and tuning it should help.

I say that knowing changing fuel pressure on a TBI is a pain.
 
ZooMad75 said:
Sounds like you need to do some data logging. Talk to the guys at Howell about the combo and see what they would need to help tweak the tune.
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I have talked with Troy at Howell a couple of times so far. Sent him one data-log, he said that it looked good. :doah:
That was before the timing change, and I am betting that another run will be soon to come.
I am thinking about bumping up the fuel pressure first, but I am also curious now about what further timing changes would do. I never thought that I could go up to 12*would work on a TBI engine.
 
Gotta have something to hold the double pumper, already got a doubler, so more double, eh?
Fork an eh!
 
beags86 said:
Maybe a set of double hump heads. Toss those get heads you got on it, in back of the pink truck. I'll scrap them for you when I come get pink thing.
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Ok! But it's gonna cost double! Of course I set the price. Eh
 
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