In a motor built for track only, and 3500-7500, when do you begin to see gains with a tunnel ram setup over a single carb setup? And how substantial are those gains?

The reason I ask is, I wonder if my motor is being choked by the 750 dominator and victor jr intake, especially considering the manifold has a 4150 type flange, and thus requires an adapter to mount the 4500 flange dominator.

If I were to rework the setup, I'd either sell the dominator and adapter and get a barry grant carb (something in the demon series) OR sell the the intake and adapter and pick up either a Brodix intake with dominator flange that would match my heads, OR sell the whole shebang and go to a tunnel ram and dual 500 or 660 setup.

But I don't know which setup will net me the most benefit.

Engine: 407 Ci, 40 over 400 splayed mains, poured with rock block (half), steel crank, Eagle rods, Wiseco pistons, molly rings, solid roller Reed cam Duration at .050 is 262/267 ADV Duration: IN 296 degrees, exhaust: 302 degrees Lobe Lift: IN .412" EX .417" Vavle Lift: IN .618" EX .625" @1.5 RR Valve Setting: IN .020" EX .022, zero decked block, Brodix Track I heads, 2.01 intake, 1.65 exhaust, intake runners 215 cc, triple valve springs, compression ratio 13.2 to 1, receiver grooved heads, block wire head gaskets, Victor Series intake, 750 Dominator carb., Hooker 2 inch longtube headers, 3 inch X pipe with 1 chamber Flowmasters. Transmission: Turbo 350 trans. with reverse valve body, 4400 stall converter. Rearend: 12 bolt GM differential, 456 ring and pinion with mini spool. Ignition System: MSD ignition, 7AL-2 with two-step, with rev. limiter pills. General Information: Channel for 4 link suspension. Car Weight: 3090 lbs. (without the driver) Brake line lock, trans. brake, B & M rachet shifter, Southside traction bars, 8 point cage.

Car will run high 6's in the 8th on motor only as it sits.

I am sure some of you have an opinion on this... let's hear it. A desktop dyno sumlation possibly?

 

I think you've hit it right on the head. The Vic Jr. is really holding you back. A Super Victor either for 4150 or 4500 carb has longer, straighter runners and should be about right for your Track 1's. It also has more plenum. I'd be looking in the 900-1000+ cfm range, either a 4150 or 4500. Talk to Grant or Braswell. The equivalent Brodix manifold is very similar.

I don't think the TR will be better for you.

FWIW, and this is just an opinion, your 215 cc Track 1s might be a little small for your 407 inches. This should be a 700 fwhp engine, and I don't think the heads will support that wery well. Personally I'd use Magnaflow or Dynomax Ultraflow welded mufflers. No flame on your setup; it runs very well! Just my opinion.

 

First guess on this is another intake would work better. I'm going to go out on a limb here and say that the Super Vic or Tunnel Ram should work. A total of 900-1000cfm out of one carb and a bit more if it's going to be out of 2 carbs.

Knowing how good those heads flow would help also, just to see how close that camshaft is to everything else in the system. BTW you gave us everything BUT the LSA and ICL of that camshaft, that is about as important as everything else.

One thing that's going to change with the intake is the cam. A Vic Jr to a Super Vic is a good sized change but a Vic Jr to a Tunnel ram is a HUGE change, so the right camshaft is going to be a bit different. That camshaft looks around the right size for your setup, but i'm sure it will be helped with more CFM out of the car as much as anything at this point.

Bret

 

Geez that car is light, have you dynoed it? I think it shoud run a little better than 6.90. I would definately try a bigger setup.
Seeing as the EFI 383's are using 1000 CFM throttlebodies, I would put me a real dominator on it and see.


David

 

I bought the car as it sits, so those are the only specs I have so far. I emailed reed racing with the grind number of the cam to get the rest of the info.

I haven't dyno'd it yet...I've only had it about 10 days

What do you think of the brodix hv1002? it's about 7 inches tall, and a dominator flange. Supposed to be matched ot my heads.

Here is the flow chart for the heads from their site: http://www.brodix.com/onlinecatalog/...ODIX-T-1sm.gif

the heads are limited to around 7000rpm according to brodix, so I am anticipating a 6800 shift rpm (which matches what the previous owner told me)

 

was this a nitrous motor? that could explain the small carb, intake, heads and intake valves and large exhuast valves.

 

it was built for nitrous, but hasn't been sprayed. In fact the motor only has one run on it.