what is a "stage"

[Bandit72]

i've heard of stage 1, 2, and 3 in many different things from shift kit's to port and polish on heads...what does this mean? What is the difference between stage 1 and 2, or 2 and 3?

Ryan

[Ghoste]

It's just being used to indicate a level of modification.  Most of the time, each stage represents greater modification but occasionally it's the other way around.  That's it, nothing more or less than that.

[daytonalo]

STAGE 1 =A LITTLE MONEY
STAGE 2 =MORE MONEY
STAGE 3 = BEND OVER !!!!!!!!

[Ghoste]

 

[konigcharger]

STAGE 1 =A LITTLE MONEY
STAGE 2 =MORE MONEY
STAGE 3 = BEND OVER !!!!!!!!

[mikepmcs]

I'm at stage 3($$$$$$$$$$$$$) and my car still ain't fast enough out the box...Is there a stage 4?

[Ghoste]

There was in the Max Wedge days so you may end up having to create Stage 5 or even 6. 

[Chryco Psycho]

I have never really figured it out , I port heads correctly meaning all the port work is done , why do 1/2 the job 

[Challenger340]

It's just being used to indicate a level of modification. Most of the time, each stage represents greater modification but occasionally it's the other way around. That's it, nothing more or less than that.

As mentioned, most professional porters/shops have "levels" referring to the amount of port modification, they will apply to a set of heads.

The more porting applied, generally speaking, the more FLOW enhancement from the port, and, alot more labor(money).

More FLOW = More Horsepower POTENTIAL, if complimentary parts are applied.

That said, it is important to understand, that the more flow from a set of heads,  is NOT always more power, if the engine cannot utilize the extra Flow.
The Engine must be turning sufficient rpm, with the right cam profile & induction to utilize the added "volumetric efficiency", which is really what we're reffering to here.
The term "stages", is their way of targeting the Porting, for the performance level your seeking.

Generally; (but NOT always, depending on Company)

Stage 1; Intake gasket match & Bowl cleanup, "clean" the port all the way through, however, minimal volume changes applied.
This is a basic port job, usually to cleanup existing minor production flaws and recent rebuild work(if thats the case) in a head. Also, usually, the best flow gain for dollar spent.

Stage 2; All of above applied, with the addition of divergence angle Volume increases in the port, back to the intake face, including the short turn & roof blending. Guide blending with Volume changes in the port are applied, where velocity degrease at the bowl compliment the targeted port demand/Camshaft. Head flows more than Stage 1.

Stage3; All of above is applied, with the addition of "maximumizing" the existing port Volume, divergence & chamber reworking based upon Flowbench testing. Really, "making a new port flow characteristic".
Generally, each shop will have their own, "007, top secret stuff", in the way of Valve seat angles also incorporated, and the ability to apply & test it themselves. Usually a FLOWBENCH test Sheet is supplied proving their work. Head flows more than stage 2.

Some photos of what would be considered a "stage 2" type port job, not because of the "portwork"(basic),  so much as the "guide" & "bowl" work done in the second photo
[/img]

[/img]

Thats my opinion of "stages", as it applies to my shop. Others may vary. Best check around at whatever shop you deal with, but theirs will probably be similar.

Bob out.

[mikepmcs]

that's purrrrrtyyy!

[Hot_Rodder]

I'm at stage 3($$$$$$$$$$$$$) and my car still ain't fast enough out the box...Is there a stage 4?

Stage 4, sounds like time for a supercharger to me, lol.

[Lostsheep]

I'm at stage 3($$$$$$$$$$$$$) and my car still ain't fast enough out the box...Is there a stage 4?

[fast360]

Its kinda like the 3/4 race cam thing, it doesn't make any sense. then again i never really hear anyone say that anymore.

[Challenger340]

Just my opinion, but I've heard, the "3/4 Race Cam" thing, was evolving "lingo" used way back in the late fifties ?, to describe Camshafts that were at that time, becoming bigger & bigger duration-wise, and exceeding the 270 degree mark, which is "3/4" of the full circle which is 360 degrees.

Just some trivia for 'ya.

Bob out.

[Chryco Psycho]

Actually the 1/2 or 3/4 or full race cam evolved from the early 50s & the flathead Ford , they had upgraded cams available in 4 different grinds above stock , back in the early days of hot rodding