dr ls7

266/274 109icl 665/650

Engine specs
427ci ls7
Cary 285cc ls7 head
Cary 2pc full cnc ls7
12.25 comp
E85 fuel
Pro systems Sv1 carb
Custom 1 7/8 headers
Custom front mount msd dizzy, 7531 box
N2o 175/225 hit
4000 rpm custom nitrous conv

Dyno Junkie

1 7/8" headers may be a bit on the small side, especially when on the bottle.

I use 1 7/8" on a cammed LS3.

87silverbullet

iTrader: (11)

Can't give feedback on the cam not knowing what's its going in. Could be a light 2700lb stang or a 4100lb big B body, see what I'm saying?

I'd run more compression if the fuel is going to e85. Good choice on head and intake choice.

I think you are wasting your money on the sv1 carb. It will not make a dramatic increase over a 4 hole carb on your motor. You don't have enough cubes or compression. You need bigger headers. What block? LS7 blocks are known to have thin walls and are prone to cracking especially on the bottle.

I don't think a custom converter is necessary for only a 175 shot.

dr ls7

Its a 2900lb Holden Torana (Australian muscle car) street registered

Using new factory ls7 block.

Sv1 carb for diff look.

12.25 plenty of comp when mixed with nitrous ( 1 x 19 gallon fuel cell, 2 separate pumps and regs)

Custom converter = a few little extras than the norm off the shelf n2o conv

Custom Nitrous outlet single stage system with halo plate set up to run up to 350hp

Headers are yet to be built. May still go 2 inch headers

87silverbullet

iTrader: (11)

Still wouldn't use an LS7 block if it was used or new. Call up Race Engine Development in Oceanside, CA and ask them how many LS7 blocks they have with cracked cylinder walls that they have to re-sleeve.

It's your money to waste so if you like the look of the sv1, so be it.

My point on the compression is that you can run pump gas on that much compression these days. If you are going e85 might as well bump it higher and take advantage of it. No need for 2 pumps, 1 pump 2 regulators will be ok.

If you are going with a halo setup why do you need 2 regulators since it is a dry setup? Plus how are you going to feed it extra fuel since the carb is only going to be able to mostly provide fuel for the motor and not the extra nitrous. Put a wet plate on it and be done, especially since you are going carb. I know Nitrous outlet makes halo setups for EFI and they do custom stuff but I don't see how you are going to run a halo on a carb setup

2 inch would be a minimum on that motor. Stock LS1's pick up power with 1 7/8 headers over 1 3/4's

To me, you need to do a little more research.

Sales@Tick

iTrader: (3)

PM sent.

dr ls7

Dave at Nitrous Outlet set the halo plate as a wet system fed by holley black pump and aeromotive bypass reg.

dr ls7

martin.... email sent

Sales@Tick

iTrader: (3)

That is a very good looking motor, what kind of car is it going in?

87silverbullet

iTrader: (11)

That's just a plate then, a halo system is a dry system.

Sales@Tick

iTrader: (3)

He actually has a plate set-up that distributes nitrous and fuel in a "halo" ring. I've only seen Dave use it on E85 set-ups, but he might recommend or use it on other set-ups using gasoline for their nitrous enrichment.

If you look at the picture again, you'll notice that the plate has 2 fuel and 2 nitrous fittings on each side of the plate and that the fuel and nitrous solenoids have 't' fittings for two lines to exit that go to the plate. It's more of a perimeter type deal if you could see it closer, but it basically has the fuel enrichment entering on opposites sides of the plate and the nitrous entering on the other two sides of the plate opposing one another.

If you were to then see it from a top down view the open plenum section of the plate itself is a circle. I'm sure it has small holes drilled in a "halo" ring all around the perimeter of the circle spraying fuel and nitrous that the plenum of the intake then pulls into the runners and feeds the motor with.

It's a really neat system, maybe Dr. LS7 has some more pictures of it.