k ive got what i belive is a very nice bottom end
4 bolt mains roller block.
scat crank and rods , k.b pistons,
milodon low profile stroker pan

my engine builder gave me a head choice, vortecs or swirl ports
and being the swirl ports were so much cheaper i decided with these
theyve been decked and all that, along with race valves 1.90 1.60

be it the low lift of the heads, i went with an extreme 4x4 cam,, the hottest one they make (474 lift, 111 sep, something like int 230 dur)
ive got comp pro magnum vertical link bars.

my engine builder said theyd be good heads up to about 380 horse, and thats exactly what im expecting with a weind stealth and a 650 mech secondary demon with full msd(6al,85551,blaster 2)

should i just try to sell these heads before i even throw it on the dyno
i keep hearing im gonna be disapointed with my dyno results
im just looking for a 400ish horse street motor.

ps... anyone want these brand new 350 heads?

 

You are going to use 1.90, 1.60 valve heads and a 4x4 cam in a 383??????????

I wouldn't go with either heads. Get a nice aftermarket set around 200cc. Also, from the specs you provided, that cam doesn't sound very big.

Is this a roller block?

Remember the 380 horses your builder is talking is at the FLYWHEEL - not at the tires.

Just my 2 cents.

 

The cylinder heads are where all the horsepower and torque comes from. A small cam with good heads will make more power than a big cam and bad heads. 2.02/1.60's are standard "race" valves, not 1.90's. I wouldnt use swirl-port heads on anything but a stock rebuild. You need to pony up the money for a set of Trick Flow 195's or AFR Eliminator 195's. Or even the Vortecs with upgraded springs (Manley 22410-16 springs and 23652-16 retainers) would be much better. There are people running 10's with the Vortec heads.

Keep in mind with a 383 that the connecting rods can hit the camshaft unless special care is taken during the assembly process.

 

swirl ports are some of the WORST HEADS available for a max performance 383 application, the vortecs are significantly better heads, ESPECIALLY THE LARGE PORT VORTEC HEAD VERSION,

http://www.sdparts.com/product/25534...inderHead.aspx

Large-Port Vortec Cylinder Head Flow
INTAKE EXHAUST
Lift Volume Lift Volume
0.200 128.6 0.200 100.8
0.300 188.4 0.300 138.6
0.400 234.8 0.400 154.4
0.500 257.2 0.500 152.5
0.600 263.2 0.600 163.8
0.700 269.1 0.700 167.0

standard vortecs max at about 230cfm
swirl ports at about 200 cfm

 

You could go with a Dart or RHS vortec head as well, it would be a cheaper route. Also World has some very reasonable complete iron heads too.

Seth

 

I agree with Bigseth.

It sounds like your engine builder doesn't know anything about TPI or is trying to rip you off.

 

hey, pennocks91ws6, where in alberta do you live and who's your engine builder?

 

k, hes got some nice worked over vortecs with guidplates, (**** self aligning garb) ill prob just put those on and try to sell the swirlys

the 1.90 is a stock sized valve, but its still a race valve

i live in drumheller
engine shop is gts machine and dyno,,, trust me , these guys are the ****,, they are responsible for the fastest street car in alberta. when you walk in the shop, all there is is like 2000 horse motors everywhere( mostly mopar) and cranks, heads blocks everywhere

i know about the rods hiting the cam, and yest the block has been notched,
the cam may sound dumb, but i garentee everyone will be surprised by the power of that bastard

anyways,, i guess ill try ebaying the heads for like 300,, ill prob lose like 200 in the process but w.e

thanks all
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t.p.i... whats that? lol sounds like some sort of expensive way to get lousy results at anything but milage and winter driving .. if i wanted f.i,,, id go with an ls series

i had speed density garbage