1BADWS6@STENOD

iTrader: (6)

I have a 416 LS3 stroker short block all assembled and ready to go. I built it with the intentions of using ET 4.100 LS7 heads with 250cc intake runners and stock ls7 intake. The motor with those heads and 72cc chamber was gonna be about 12:1. At this point I'm just trying to get the car on the road, so i'm just gonna use the dart heads I already have. The darts are Futral/Meaux ported, 2.08/1.60, 64cc chambers...but only 205cc intake runners. With those heads the compression should be around 13.4:1. Obviously I will have to run it on E85 with that much compression. The darts have smaller runners, but 1.5 points more compression and i'll be using a fast 102/102 combo with them. I'll be sticking a very large hydraulic cam in there, somewhere in the high 250's low 260's duration and headers that are a tri stepped 1 7/8"-2"-2 1/8" primary with 4" merge collectors (also already have).

Now my question...what do you think the difference in power will be between the square ports and the cathedrals. Hopefully after this year i can get the ET heads or maybe a 245cc TFS head. Just wanted to see what you guys thought i would be giving up going this route.

Thanks!

OUTLAWZ RACING

iTrader: (9)

Dunno but id say atleast 30 -60 hp. The compression and small runners that thing is going to rip. I dont see why it shouldent make 500+ to the wheels.

1BADWS6@STENOD

iTrader: (6)

Also i'll be running a 4L80with a trans brake, 3800 stall, 9" with 4.11 gears and a 325 drag radial. Just to give more about the combo

dwill73

I would buy the Ls7 small bore heads from Cary at Mast. They don't advertise them anymore, but I'm sure he would make a set for you upon request. He can mill them for what ever cc combustion you want also.

1BADWS6@STENOD

iTrader: (6)

The only reason i'm not getting the LS7 heads is money right now. The car has been down since 2005 and I just wanna get it back together. I already have the darts, so rather than sell them for pennies and have to shell out $3000 for the Mast LS7....was just gonna run them for now. I was just curious as to what I'd be giving up. I'm thinking not all that much with the added compression and better intake manifold. Like Outlawz said earlier....should come up fast with that compression and small chambered heads

kevin kuether

iTrader: (1)

Only place I think it'll give up a little would be the upper rpm range. If the heads were ported well I doub't you will lose any more than 40 hp.

1BADWS6@STENOD

iTrader: (6)

286 other people read this but nobody else has any insight?

1lejohn

iTrader: (9)

On a 416 with a hyd roller you won't be giving up much. Why ? because 1 the smaller cubic inches don't need as much head. 2 you won't be spinning real high with a hyd cam. 3 you would be intake limited with any of the composite intakes before you run out of head flow. 4 the cath ports flow well enough. If your having them ported thats even better. I'm thinking with the smaller 205 heads the car will have awsome throttle response and rev quickly with a broad power band.

The cam may be alittle big. Was it ground for the rect ports or the cath ports?

I'm thinking most 416's make 480's to 520's you should be around 500.

If you went with the 245's and the cast alum intake and a solid roller you might make 550-575. Then you would be cubic inch limited or you would have to spin it up high

racerfox

iTrader: (4)

if your willing to wait untill the 8th of may my 416 with tsp 237 and cam is getting dyno tuned so i can give you some figures right now there on sale for
2100... just an idea

lstvr

I have a 416ci with Dart 225's on, its 532/502 rwp with ITbs on, with a FAST it was about 25bhp less, but with a bit more torque, and less rev range.