Engine: Lean Condition WOT R3 Clone

[Ian Mackellar]

First thread for a long long time,so here goes. Studebaker 320ci,running a R3 style airbox,. 750 Performer,solid floats,.120 needle and seat,choke snout has been milled off, aeromotive fuel pump with map referenced bypass reg.delivering 9psi(however will deliver 15psi when trying to sort fuel starvation at WOT)Roller cam, rockers etc, 7lbs boostfrom SN2000.On the dyno have achieved good idle,mid range AF however we cannot get enough juice into it at WOT. Have opened up secondary jets but it just wont take the gas.todayI plan to start restricting the hi speed air bleeds to see if that will improve. .any thoughts any body would like to put forward.

[PackardV8]

Have you confirmed the secondaries are opening? Inside an airbox, it's difficult to know WIGO.

jack vines

[Ian Mackellar]

Mechanically they open to full travel. Part of the next step is pinning open the air door to ensure it is opening during operation,however that can cause bogging on the secondarys during transition but at least it will tell me if they are functioning.

[SN-60]

What a good looking engine!....I like the nicely done intake setup for the supercharger.

[Ian Mackellar]

thank you,quite a bit of work to do that,but not many alternatives for cold air on a GT

[starliner62]

It will never run right...the brake booster is on the wrong side of the car!!

[Lanny Bertram]

I recently converted the 1406 Performer on my R2 to an AFB Clone as per Ernie Rizzolo's instructions. One of his tricks to ensure the secondaries are opening is to tack weld the linkage at the point shown in his photo below. I did this along with drilling the air door counterweights to lighten them(3/8" drill bit I think) and I am very pleased with the way it turned out.

[doofus]

I have several afb basket cases handy. if you need a "hard part" lid or base holler. with a turbo you need 2psi fuel pressure more than boost pressure i imagine you are in same boat. a carter strip pump feeds an r-2 fuel pump as the reg. things can go wrong at 18+ psi though. still working on that. Good Luck Doofus

[doofus]

Read the booklet that came with the carb, sounds as though you will shoot your self in foot. air bleeds allow fuel to emulsify or get frothy before going into air stream, restricting them will cause larger droplets of fuel which wont burn as well , Doofus

[gordr]

Is the fuel inlet needle and seat large enough to supply the fuel demands at wide open throttle?

[Mike Van Veghten]

Ian -

There's a LOT going on here, but there's a lot more questions to be asked.
I suggest going back on the dyno and sorting thru one thing at a time.

One thing, you mention..."it won't take the gas"...
What exactly does this mean ? the throttle opening, the actual fuel. Have you tried slowly opening the throttle, vs. a hard throttle down ?
Is the fuel pressure checked at idle or wide open throttle ?
You mention nothing about ignition timing. Low timing AND too much timing will limit the engine rpm when under boost. Low for one reason, and too much for another reason.
You also don't mention the ignition itself. Points, electronic...what type ?
I would not start messing with the air bleeds unless you know exactly what that outcome will be. Normally under 7psi of boost, a stock carburetor should at least achieve full throttle.
Normally the "FUEL" (NOT the air) circuits need enlarging for supercharged combinations. The fuel passages inside the carburetor need attention.
Also, the springs on the metering rods need attention in a supercharged Engine. Those rods need to lift fully and as quickly as the rpm does.

A ton of stuff that you don't mention needs attention.

Good luck

Mike

[70Avanti2]

Could you be making more than 7 psi Boost? What is the Paxton rated at?

Is your fuel line big enough? Are you running a pusher fuel pump close to the fuel tank? I would think fuel pressure would fall off at wot if it was a fuel delivery problem.

[LugNut]

Wow! What a beautiful MOTOR, Please note that I use the term motor instead of ENGINE... That's just a knockout, What kind of horse power are you guesstimating? How about some more pictures when you have time. Are you using Golden Hawk Xmission/rear end?? Ken

[conrad01]

ok try this. A afb carb runs springs and metering rods for fuel delivery on the secondary's. If you run a it in a enclosed box isn't the boost just pushing the metering rods down causing the bog or lack of power at wot.. The primaries run jets so its all mechanical.. The 4bbl on my 289 is all adjustable but mechanical when it comes to metering the fuel for the secondary's. You may need a carb that does not rely on vacuum for the 4bbls

[Ian Mackellar]

It will never run right...the brake booster is on the wrong side of the car!!

Not from where I sit buddy!...actually we can handle it both ways down here