Plugs still white!!!

[Blown 472]

Then you should have a good vacuum signal. What size lines are you running from your tank to the pump??
correct me if I am wrong but pressure is a function of resistance, you can have all pressure you want in a 5/16 line and no volume, or pressure and more volume in a 1/2 line.
[ January 03, 2003, 07:59 AM: Message edited by: Blown 472 ]

[Hotcrusader76]

Blown 472:
Ok, not to start a flame war, but I am not buying the too big carb thang, I have a friend (believe it or not) who has a 340 mopar, flat tappet cam, 11 to 1 ish comp in a car that has a 950 hp on it, no bog, no flat spots, off idle stand on it and it flat huals ass right to 7 grand. So I am confused now. Scotts motor is 8:1 on compression. Big difference there, no?

[Hotcrusader76]

Dans66Stevens:
I don't by the carb size thing. I have a good friend with a 283 SB and he runs a 780 cfm Holley. The car runs great. So this 950 should work on a Big Block.
Check the manifold bolts...... Apples and Oranges here my folks. 780cfm Vacuum secondary? Almost positive it is, which is still big for a 283 but should work considering the secondaries will only open as much as the motor allows. What type of cam and compression is he running also...

[Hotcrusader76]

DUCKY:
Am I not correct in saying that if I had insufficient fuel volume, then my pressure would also suffer? I have a gauge on it, and it never leaves 7-7.5psi. After a WOT run, I shut it down clean, and pull the bowl screws out, the bowls are full. And I have checked the intake and carb base for vacuum leaks with propane. Guys keep in mind too, I have the little tiny oval port heads. The intake ports are smaller than that of a 350!!! Is that free flowing pressure or static?

[78Eliminator]

Ty,
What's the deal with these guys not running their dual setups not squared? I thought it was pretty common to loose the power valves, jet higher and square for a dual setup? You don't loose a whole lot missing your powervalves. We're not talking about daily drivers here where "streetability" comes into play. Anyway, I guess there are many ways to set up a carb, I just thought the simpler, the better.
J

[Hotcrusader76]

To each his own...right J? Don't try to start another Power valve thread again...LOL
058...where are you on this? LMAO

[Blown 472]

Hotcrusader76:
Blown 472:
Ok, not to start a flame war, but I am not buying the too big carb thang, I have a friend (believe it or not) who has a 340 mopar, flat tappet cam, 11 to 1 ish comp in a car that has a 950 hp on it, no bog, no flat spots, off idle stand on it and it flat huals ass right to 7 grand. So I am confused now. Scotts motor is 8:1 on compression. Big difference there, no? Maybe, but the ports are big and so is the cam, he said he has the small port heads which should give good velocity in turn which should give a good vac signal at the carb, perhaps a vacuum gauge is in order??

[Blown 472]

One more thing and the reason I bring up the mopar with the big carb, look at the 340 six pack, cast iron exhaust, mild state of tune and 1400 cfm??? that is the reason he put it on.
And in no way am I bagging on anyone, just playing the "why" game, I get it enough from my kid so I need to play it myself.
[ January 03, 2003, 02:19 PM: Message edited by: Blown 472 ]

[Hotcrusader76]

No sweat there hoss... wink
Team G manifolds (which he states he uses) and the cam profile provided (that is the correct profile right Scott?) I would never choose a carb larger than an 850 version (with a custom calibration alone!)
The carb of choice for his set-up as is would be a 750DP or even an 850 Vacuum Secondary (yes they do exist )
It sounds like there is alot of mix-matching of parts going on here. Right carb with the right block but with the wrong cam and wrong heads. Oh well, we are all here to help, not badger one another, so please don't be offended if I came off strong... argue

[058]

Hotcrusader76:
To each his own...right J? Don't try to start another Power valve thread again...LOL
058...where are you on this? LMAO I'm here...just lurking. Not sure I want to get involved in this one after that P/V deal and since I don't have much info on his particular carb. But just reading whats here I would drop a heat range or 2 on the plugs first and then go back and recheck everything, Ducky did say when he activated the fuel side of the nitrous the lean pop went away but lost power too. I think the jetting is off for a 950 [90s/94s] considering a 4781 is jetted at 80/80 with p/vs. It would also help to know what kind of fuel he is running, if its pump 92 unleaded then that is a big part of not coloring a plug. Read plugs like its running alcohol. Fuel pressure should be taken as close to the carb inlet as possible. I've seen guys take the f/p reading from the pump and have 7lbs but change it to the carb inlet and it drops to 4lbs. What about f/p regulators? bypass or inline? A Holley inline can restrict volume but still show pressure. How about engine timing [total] not enough and the cyl. temp will run off the scale. Hows that for not wanting to get involved?