EightballZ

hey guys,

you may know that 1st gen toronado drivers are kinda limited to the stock low rise intake due to hood clearance, which can be an issue if you modified your engine.

stock intake height is only around 2 1/8" (IIRC) so no aftermarket performance intake will fit w/o hood modifications.

since theres only one (expensive) aluminium intake on the market w/o any improvements except for weight savings...why not cut it open and open up the runners or let someone port it?

anybody did that kind of modification on an intake?

won't be worth the money i fear..

http://www.appliedgmc.com/prod.itml/icOid/568

Kennybill

I always heard that the early Toro intakes flowed good so except for weight savings imo, it seems like a lot of $ and work for possibly a little gain.

joe_padavano

Hmm. That looks a lot like an O4B, with injector bungs added. Cheap at half the price...

By the way, I'd go Extrude Hone before cutting and welding.

EightballZ

olds FAQ states: The height on a stock 455 intake is 2 3/4", a Toro intake on a 455 is 2 1/8".

so...O4B should be in the 2 3/4" range since its a stock height style intake (??)

by the looks of it ..i cant see where you could mill off another .625

http://product-images.highwire.com/1...ldsint-004.jpg

joe_padavano

Yeah, I meant to say "...except for the carb height". The runners look the same. I wonder how much you could mill an O4B carb pad.

70Post

Not much....just looked at one and the pad, at the closest spot to the outside/top of the highest runner is probably 1/8" or so above that top/outside runner surface.

Have you considered checking the air cleaner assembly closely for clearance and then trying to figure out if you could modify an air cleaner in more of a "dropped base" style??

In other words.....see what actually is going to interfere/hit the hood underside and, depending on the part that interferes, make some subtle mods to that part.

svnt442

Even if you could mill an 04B down far enough I think that would cause issues with fuel puddling in the base of the intake because there wouldn't be enough room for the fuel to properly mix before the turn.

joe_padavano

The fuel had better be mixed before it leaves the carb. You are correct in that a tight turn can cause the atomized fuel droplets to fall out of suspension and puddle, however.

Run to Rund

Olds 400 and 455 NHRA stockers have run 10's with the stock intake, and my street/strip car has run mid 11s with the stock Tri-Carb intake and carbs. Thus, you should be able to modify the engine quite a bit before the engine runs out of air due to intake manifold design.

EightballZ

great info

when would you reach the point where the engine runs out of air with a stock intake?

svnt442

Long after you run out of traction in that front wheel drive car.

EightballZ

i see..no worries concerning the intake.

but what about stock exhaust manifolds?

copper128

The Toronado manifolds are a simple log type, so not a model of efficiency, but they should flow better than all other factory manifolds with the exception of the W/Z set.

You might be able to open up the exit diameter a bit, too.

83hurstguy

exhaust manifolds are the biggest restriction on an Olds engine IMO. Porting them isn't easy/cheap and doesn't offer a ton of gains as you are only reducing some frictional losses and not really getting any tuned length runners to help with scavenging. You can open up the exit with a carbide bit and try to run 2.5" exhaust out to the back, should help give you the best practical gains for a reasonable cost.

jfb

on a earlier build I had my exhaust manifolds extrude honed and used factory cut outs and picked up about 31 rear wheel horsepower or around 43 gross. I had limited room for headers and of course expense and this worked excellent.