[Mustangsaly]

I Just Bought/Ordered a set of hooker headers (Summit Header # HOK-2453HKR) the header Collector Diameter is : 2.500 in. 3-bolt flange Collector

MY QUESTION:

do my Hooker Headers 2.5" Collector 3-bolt Attachment flange need a 2.5" (in) to a 2.5" (out) Reducer ?


or can I use a 3" (in) 2.5" (out) Collector Reducer on my 2.5" Header Collector ?

I think I'm Going with 2.5" from the header to rear bumper, but was looking in my garage and I have a set of 3" (in) 3" (out) Reducers and a set of 3" (in) 2.5" (out) Reducers.


this is for a 87 Suburban 4 X 4


Thanks

Mustangsaly

[onovakind67]

The headers come with the flanges to weld on your existing 2-1/2" pipes. A 3" reducer won't work.
I wonder why Hooker doesn't make this type header for cars, as a 2-1/2" collector is much better for a 1-5/8" primary tube than a 3" collector. I bought a set of the 2453's at a swap meet just to get the collectors for my Nova.

[Mustangsaly]

Originally Posted by onovakind67

A 3" reducer won't work.

thats what I thought, you think the 2 1/2" exhaust will be a better choice than 2 1/4" exhaust from header to rear bumper with no cats on a stock 350 tbi ?

stock except for headers and some chrome. chrome is worth ? what 15 or 20 HP ?

the 350 is a GM crate engine that was new dec 05 and was put in a 90 chevy P/U till march 06 when the tranny died, so its fresh.

my block #s 10243880
mortec says
10243880...350...95-00...2 or 4 bolt main...Vortec truck, Gen.I crate motors and "ZZ4", roller cam, one piece rear seal

I pulled pan its a 4 bolt main block



mortec says heads are head #s
14102193...87-up...305/350......1.94"/1.5" valves






Mustangsaly

[onovakind67]

As long as you're choosing the pipe, I'd choose 2-1/2" all the way back. If you reduce the pipe diameter to 2-1/4" for some reason, do it at the muffler behind your crossover.

[Mustangsaly]

I ordered 2 1/2 x 2 1/2 reducers. it will be 2 1/2 from headers to rear bumper no cats and a crossover pipe or X pipe or H pipe. its a hunting towing rig, my sons 1st vehicle. thats whats the headers and chrome are for, chrome is worth what 15 or 20 HP ?







Mustangsaly

[MI2600]

I think the dyno desk top rates chrome @ 25.365 hp.

I agree. Go with 2 1/2".

[Mustangsaly]

Originally Posted by MI2600

I think the dyno desk top rates chrome @ 25.365 hp

YES


Mustangsaly