The Valiant breathes fire!!!

[Syclone0044]

I'm posting here at Chris's house (Prince Valiant), we just got back from the maiden voyage of the Valiant with the new motor. That thing rips pretty damn good!! Torquey motor. It was funny, we pull out of his driveway and within 100 feet he's romping on the gas like old times. The engine is still tight but with the way Chris stands on the loud pedal, it should be broken in in no time!! :headbang

[Ricky Bobby]

bout time :goof

[Rocket Power]

*starts chant* BURN - OUT - PICS, BURN - OUT - PICS, BURN - OUT - PICS, :3gears: :3gears: :3gears: :goof

Cool ! Glad to hear it's running well :thumbsup

[Prince Valiant]

Cool ! Glad to hear it's running well :thumbsup Well, "it's running" is more accurate....I've got a new carb on here and I am pretty clueless how to tune this particular one, so to the "carb shop" it'll go for some fine tuning. Plus the spark plug wires I am running right now are the sacricfical kind, IE three are already burned through and are intermittently causing a couple of misses. As well, it was discovered that I have absolutely NO third gear...seems that the shifter is pushing the shift rods far enough forward to engage gear, leaving me coasting when I try :mad:

BUT, those are relatively easy fixes....get some custom wires this weekend, lume them up well, said visit to the carb shop for some tunin' and some learnin', and see what I can do to correct the shifter...I already have one that could be put to good use if need be...so all fairly simple fixes. That and a new power steering pump and it should be just like a piece of sh*t again! :thumbsup

[Cryptic]

hurry up and finish that car, so you can help me with the 65' Bonne :thumbsup
like cuz, i have so much free time to even get to it

[Prince Valiant]

No prob :thumbsup

[JC70SS]

:thumbsup Is she good to go out for a little bit on wed night like to Pistol Petes?

[Prince Valiant]

I am going to tune it up a bit when I get home so that it's ready to go to the carb shop on thursday, so it should be. Joe, you should stop by on Weds on your way to pistol pete's and we'll see where I am at...it shouldn't be too much of a problem to get it there :thumbsup

[animal]

What carb are u running?

[Prince Valiant]

Holley 700 double pumper (mechanical secondaries)

[JC70SS]

what size cam is in there Chris??

[animal]

Holley 700 double pumper (mechanical secondaries)

Sweet, that's about what I was thinking of running on mine. Aren't they tuned pretty well out of the box?

[Prince Valiant]

The Holley 700's are tuned pretty well for about a 400ci motor...they are a little rich on the 350 sized motors, particularly at idle....the idle circuits, accelerator pumps, jets all tend to be a little large. It's not too hard to get right by adjusting the floats simply enough, but for now for now, I'll leave it for the pros to fiddle with, lol. A 600 or 650 would have done much better out of the box.

Joe, the cam is a Hughes cam (mopar only manufactuer) that takes advantage of the large lifter bases of the mopar motors...with 232/237 duration @ .050 and .542/.560 lift (that's huge lift for the duration for a hydraulic flat tappet cam...it's pretty close to a typical solid flat tappet cam for less money and maintainance), I can already tell it gives the motor a pretty decent demeanor and begins to come on strong at around 3200rpm...I haven't really reved too much beyond 4500rpm though.

[animal]

The Holley 700's are tuned pretty well for about a 400ci motor...they are a little rich on the 350 sized motors, particularly at idle....the idle circuits, accelerator pumps, jets all tend to be a little large. It's not too hard to get right by adjusting the floats simply enough, but for now for now, I'll leave it for the pros to fiddle with, lol. A 600 or 650 would have done much better out of the box.

Not sure what compression you're running, do you think it might be better with my 10.7:1 motor? Or is it still a little big? (I havent bought the carb yet, it's just as easy to get a 650 vs 700)

[Prince Valiant]

Compression won't matter for carb sizing really, more important is that rev potential of the motor...which is dictated by heads, intake, cam, etc...and of course, CR is a consideration for cam selection...so the two intermingle, but only indirectly.

I think a 700 is perfect for your vehicle...If you are expecting to rev to 6500-7000, which based on your cam you can reasonably expect that (though I don't know much about your heads....you had mentioned that they are in fact ported, correct?)

The only thing is that it would be very difficult to find a perfectly matched carb out of the box for YOUR particular motor...some tweaking is expected for your type of build-up as not many people build a 351 to your's specs.

The reason is that at idle of about 850rpm, a 400ci motor is going to draw more air through the same size venturi's, causing better air velocity vs. the 351ci motor...this creates a greater "signal" or vacum past the venturi's as air flows by, better atomizing the fuel. To slow, with too much fuel and you end up as I am...fuel just piddles out.

When they go through it I'll expect to learn a thing or two...so I'll share what I pick up from them and we'll apply the lessons to your carb as well :thumbsup: