porting 096 vortec heads

[F-BIRD'88]

Here's a SBC 408 CID with #906 Vortec Heads 2.055/1.600


Saturday July 6 , 2002
Chris - Vic Fisher
4.165 x 3.750 = 408 CID
5.700 Eagle I-Beam
Eagle Crank cast -crank
SRP -21 CC dish
C&A rings
Moroso 8 1/4 kickout pan
BG carb 950 CFM
Cast-Iron Vortec heads 2.055/1.600 Ported by Meaux
Super Victor Vortec intake w/1 inch open Moroso plastic spacer by Meaux
10.2:1 CR
1 3/4 Hooker Super Comp
Hydraulic Roller with 1.60/1.60 Cam Motion rockers
Comp Cams 242/248 -110 .360/.375 Lobes = .576/.600 on 106 CL
Chevron 93 Prem Pump Gas
-------------------------
36 deg BTDC
-------------------------
change = add collector for 24.0 inches ( 3.000 x 8.500)

164 cranking psi #2 cylinder 8 to 10 pulses

3.5 CFM Blowby


I like that one ... a lot.

[the nitro man]

my idea of streetable is more in the lines of Tony. what F-bird considers a race engine, i consider a street engine with the exception of the high compression that won't let a "street car" use 93 pump gas. power brakes are not a problem, I'm used to crappy brakes. comes with the territory of using big (240 @.050" +) cams with power brakes. the 3.42 gears was for the 406 i have in my car now (the headless 406). it run just as good (maybe better) with the 3.42 gears as it did with 3.89 gears. a 350 will be a little different, but not enough for me to change them right now. I'm thinking about putting the cam from my 406 into the 350. its a solid lunati 249-259 @.050"/.543"-.561" on a 106. more than i need, but i have it & it's not costing a dime.

[maxracesoftware]

i found a bunch more Vortec Pictures on my other Computer

also found a few more various Dyno Tests with
various Engine CID sizes and Vortec Heads

a couple with ETec Vortec 200

and another Brand i can't remeber at the moment
i think its 170 ?

also i completely forgot about the very latest Vortec Dyno Test
i did on April 8 , 2008 this year.

Will eventually Post more Pictures + Dyno Data
on all the other Vortec Dyno Tests
as i get Time

The current Computer hookedup to my Dyno has only
Year 2000 on up to present Day Dyno Data on it,
i had a Computer HardDrive failure in 2000,
so i have a bunch of other Vortec Dyno 's as only hard copies in Filing Cabinets.

[maxracesoftware]

Update Info->

talked with Tony yesterday,
additional info on his Street Truck 355SBC with the 906 Vortec Heads,

after selling the Ventura, Tony put the Engine into a
full size 1981 Chevy Pickup , fully loaded, w/A/C , Power Brakes/Steering
just like it was off the showroom,
the only Mods were-> 700R4, 4.10 rear gears
and a new 4000 Stall Hughes Converter for the 700R4
and suspension Mods,

also a new Cam , CC 248/254 XR286R .576/.582 110 Centers
along with Moroso Chrome large vacuum reservoir for Power Brakes

4265 Lbs w/ Tony Driving
Run at State Capitol Raceway, Baton Rouge , LA
was 12.10 ET with a 1.59 60 Ft just like the Ventura

here's a pretty close Simulation of the Run,
however, i forgot to change the Wheelbase input,
i think its actually 118 to 120+ ?
....never dynoed with the newer Cam he put in, so i'm guessing its
around 510 Peak HP and 435 TQ



Tony went ahead and installed the 406 SBC cid into his new Vega
he just purchased...so it looks like we won't Dyno it too soon ,
instead he's going try it down the Dragstrip 1st
i can't blame him !

the old #906 Vortec 2.055/1.600 Heads/Manifold off the 1981 Truck's 355 (and prior on the Ventura)
are now on the new SBC 406cid in the new Vega,
along with new CC solid roller cam .630/.630 lift
heres a few Vega Pics ( Vortec 406 cid, 750 Carb )

[novadude]

Larry... here's a semi-off-topic question....

Do those centerbolt-to-perimeter cover adapters work OK without leaks? Which ones were you using?

Thanks.

[comp]

Larry... here's a semi-off-topic question....

Do those centerbolt-to-perimeter cover adapters work OK without leaks? Which ones were you using?

Thanks.

good question

[maxracesoftware]

Larry... here's a semi-off-topic question....

Do those centerbolt-to-perimeter cover adapters work OK without leaks? Which ones were you using?

Thanks.

Chris at C & S Performance Engines built both the 388 and the 408
He used GM's adapter/spacer version,
but has since quit using them because its too hard to stop them
from leaking, especially when you use 1.480 or 1.550 OD Springs,
you have to mill out those adapters to clear the larger OD springs,
to the point it leaves very little to seal in those areas.

instead Chris now uses Moroso SheetMetal CenterBolt Covers,
absolutely no leaks of any kind, they look great,
and offer greater clearances everywhere around the ValveTrain.

Maybe if you are using only the 1.250 OD springs,
and want a certain "Look" like for a Show Car,
would i recommend those adapter/spacers !

[z28freak84]

So what kind of Flow numbers can be achieved with the 2.055 valve on the Vortec heads??

[ctk30]

Does anyone know where I can find these pictures?

[ParDeus]

I'd email Larry and politely ask him to send them to you.

[maxracesoftware]

Does anyone know where I can find these pictures?

i'll see if i can find and re-Post those Pictures by next week

just so happened i'm about to Port a pair of those castings
for a Electrician friend as a favor for wiring new Shop Air Compressor
so i'll take a few Pics of those Heads

[ctk30]

That would be great

I actually ened up finding quite a few pics in this thread, I imagine it's the same ones you posted here

viewtopic.php?f=1&t=22571

[randy331]

Can't get in to the whole explaination on airflow and fuel flow management
air speed and pressures at low mid valve lifts science of why things are the way they are on a vortec head.

Any chance this info is out dated enough you could get into it now that this thread is a few years old?

I realize some of this type of info is proprietary info and can't always be given out, but I've done a few sets of vortecs, and airflow, fuel flow management , air speed, pressures at low/mid valve lifts science is just the areas I'm lacking.

Oh, ! and why a vortec would be so different than other heads?

I'm excited and looking forward to your thoughtful input!!

Randy

[maxracesoftware]

That would be great

I actually ened up finding quite a few pics in this thread, I imagine it's the same ones you posted here

viewtopic.php?f=1&t=22571

Glad you found that other Link has all the same Pics i posted

viewtopic.php?f=1&t=22571

the Vortecs i'm going to Port will have rough carbide finish
they will not look as good as those Pics in that Link above

[F-BIRD'88]

Can't get in to the whole explaination on airflow and fuel flow management
air speed and pressures at low mid valve lifts science of why things are the way they are on a vortec head.

Any chance this info is out dated enough you could get into it now that this thread is a few years old?

I realize some of this type of info is proprietary info and can't always be given out, but I've done a few sets of vortecs, and airflow, fuel flow management , air speed, pressures at low/mid valve lifts science is just the areas I'm lacking.

Oh, ! and why a vortec would be so different than other heads?

I'm excited and looking forward to your thoughtful input!!

Randy

Randy: This statement is and was in context to porting these heads for a situation where the engine rpm is relatively low (street motor) as opposed to a racing engine, and when used with a camshaft that has less duration/lift and overlap at/near TDC than a racey cam does.
Where the valve is relatively close to the valve seat, more of the time (average)
The port shape in the bowl under the valve job needs to be specific shaped with that in mind
so that the air and fuel move past the valve and seat, in the chamber efficiently.

This is different than what is optimum for a more racy motor with the valve further way from the seat
(more cam duration/overlap).
Look at the relative valve opening at and near TDC. On a typical racy roller cammed motor, the valve is already open quite a bit by the time the piston starts to move away from TDC, so low lift and the shape
of the bowl near the valve is less critical. .300" and up valve lift.
So the best bowl shape is going to be different than a small cammed motor.

Two different situations, two different approaches to porting the head. To get the best result on two different engines.

Oh, ! and why a vortec would be so different than other heads?

They are not...but much of the specific shape you want to keep is already there for you, on the GM vortec heads.
(relativly small cammed engine)

Larry does a great job on these heads.