I am dropping one of these babies in my truck soon.
1991 Vortec 9C1 police motor. It is TBI and I want carburated. does anyone know of a manufactur/part number of a intake that will fit this thing? We put one of these motors in a 1986 z-28 and had to drill the inner 4 bolts to make it work. Now we wanna get new intakes to fix it correctly. Also I will be going to vortec heads eventually.

Also another question.... If I have a vortec block but not vortec heads and the intake off an older 350 needs holes drilled does that sound right? non vortec heads with vortec head bolt pattern or is that due to the TBI intake??????? I am not worried about emissions too bad but the motor has a hydrollic roller cam/lifter setup ...
260+ hp / 300ft-lb torque... what could i do to bump the hp up???
vortec heads (40hp)
headers (15hp)
flowmasters (15hp each side)
Intake(???hp)
Carb (????hp)
so I could get it up to 330 or closer to 350 hp without changing the motor inards.... I dont want alot of hp. I didnt go with a bb so I could have gas mileage ...:rasta:

thanks all for any input

Gm goodwrench has a couple intakes to go from vortec to spreadbore q-jet/holley, and I think one for vortec-tbi, if not edelbrock makes a vortec-tbi intake. As for the drilling, some of the chevy engines with reverse water jacket flow had a different bolt pattern for the heads, that might be your problem. If the manifold dont bolt up it is usually for a reason, but if it aint broke why fix it? If you need PN#s let me know.

Charlo

would appreciate pn's if you dont mind...
:rasta:

Originally posted by RootBreaker
would appreciate pn's if you dont mind...
:rasta:

Here are a couple of P/N's for edelbrock products ( www.edelbrock.com) that use a carb on the vortec heads:

Performer Vortec #2116
Performer RPM Gen 1-Plus #7116
RPM Air-Gap Vortec (non-EGR) #7516


Are you sure that the motor you are getting is a L31 vortec? To the best of my knowledge they didn't produce these until 1996. I have been told that there were some earlier motors called vortecs that had a swirl inducer or something in the intake ports, but they are not what people generally refer to as "vortec".

As far as intake holes go, this is the scoup as I understand it. up to 1986 the intakes were 12 bolts with the middle ones angled. IN 1987-1995 (Fuel injection motors) They had the same port design, etc but the middle bolts now go stratight up and down. In 1996 they introduced the "vortec" (L31) heads. They have 8 bolts hoding them on instead of 12, and a completely designed port shape. You can drill these heads and fit the earlier intakes on them, but the ports don't line up well, and you risk air and water leaks

I also wouldn't plan on the flowmasters giving you 30hp just by bolting them on. They might be able to free up 30hp on a badly restricted motor, but I don't see them just giving you 30hp. Now, yellow paint on the other hand.......

Check out the "SB vortec heads with an egr? ideas for more power?" thread for a couple of desktop dyno graphs.