[RicksGTO]

my '72 455HO had what I believe to be it's original uncut system as well and it had the same bends/crush zones in it. I like a factory stock looking resto but I've got a Pypes 2.5" mandrel bent system to replace it with. It's not hard to see why these engines are supposed to pick up 30-40hp just from a free flowing mandrel bent system.

[74 SD455 Formula]

Originally Posted by RicksGTO

my '72 455HO had what I believe to be it's original uncut system as well and it had the same bends/crush zones in it. I like a factory stock looking resto but I've got a Pypes 2.5" mandrel bent system to replace it with. It's not hard to see why these engines are supposed to pick up 30-40hp just from a free flowing mandrel bent system.

I did the same thing with my 72 455HO GTO except I took off a Gardner system ( 2 1/4in ) and put on a R.A. restorations 2 1/2in "X" Pipe set up with the stock exhaust tipps and what a difference in performance.

[RAIVJUMB]

I have an NOS 71 head pipe that was from the period so it has been around a while, it has the squashed flat spots in it. Not sure i would ever use it on my car but have it in the rafters for reference. Mark

[superdutybob]

Factory SD head pipes are a whole lot nicer than those. Wow, those are unbelievable. How did these cars ever run as good as they did?

[goathead455]

There hasn't been too much going on in the HO forum so I'll give an update on mine.
This past weekend a few of us went on a roadtrip to Mission B.C. to the dragstip there.
About 700 miles one way,my GTO got 15 miles to the US gallon and made the trip without any trouble.
At the dragstrip I had a best time of 11.79@ 116 mph,my best ever.

The car is a 70 GTO with a 455 HO,TKO 600 5 Speed and a 3.73 rear end weighing 4060 lbs with me in it.

[OVERULD]

Wow, that's great mileage; the 5-speed makes a difference. My 71 455 HO M22 GTO only got 10 - 11 MPG on the trip from Atlanta to Dayton and back for co-Vention.

Your track time is pretty awesome too! Is that motor stock? What kind of tires?

BJ

[goathead455]

Sorry to the purists but the engine isn't stock.
I was using 28 X 9 slicks.
The 5 speed makes a huge difference,2400 rpm @ 80 mph.

Engine is 10:1 .030 over 455 with 7F6 heads.
The car has headers and 3" exhaust.
Tomahawk intake with a HP950 carb.

[OVERULD]

Originally Posted by goathead455

Sorry to the purists but the engine isn't stock.
I was using 28 X 9 slicks.
The 5 speed makes a huge difference,2400 rpm @ 80 mph.

Engine is 10:1 .030 over 455 with 7F6 heads.
The car has headers and 3" exhaust.
Tomahawk intake with a HP950 carb.

Nice set-up and it shows in those times and MPG!

BJ

[Judge273]

Does anyone have total production numbers on all the 455 HO cars built in 1971?

Here what I think I know:

888 All GTO's
123 nonGTO's
2,116 All TA's
166 Formy's 4-speed only?

Total?

[2manyT/A'S]

Originally Posted by Judge273

Does anyone have total production numbers on all the 455 HO cars built in 1971?

Here what I think I know:

888 All GTO's
123 nonGTO's
2,116 All TA's
166 Formy's 4-speed only?

Total?

My info shows that TOTAL W66 LS5 production was 321.

166 sticks & 155 TH400

[Judge273]

Thanks 2many,

That makes:

1,011 total a bodies w/ 455 HO
2,437 total f bodies w/455 HO

3,448 total 455 HO in 1971 cars

Does anyone know if that's correct?

[74 SD455 Formula]

Mike,
You did not include the Judge's and the LeMans did you ?

[RicksGTO]

the chart I'm looking at on YearOne.com shows the same 888 number for hardtop 455HO GTO's plus 48 GTO 455HO converts. It does not make it clear if that includes Judges, I believe it does, but I could be wrong on that. The Formula and Trans Am numbers that you and 2Many posted look right to me

[Judge273]

Thanks Jim and Rick,

I'm sure I missed the 48 GTO verts that includes Judge vert.

1,059 total a bodies w/ 455 HO
2,437 total f bodies w/455 HO

3,496 total 455 HO in 1971 cars

[2manyT/A'S]

This 72 T/A is currently on ebay & we've been kickin' it around on another thread but I think the vid deserves a separate post & what better spot than here?

Also,it will give the SD guys a chance to "go for a ride" in something a bit faster than they are used to.

http://www.youtube.com/watch?v=3ne__XwDoK8

I sure enjoyed it (about SIX times already)

[superdutybob]

I thought we weren't allowed here!

Pretty car. Too bad it's not an original 4 speed car. Didn't seem that fast to me! LOL

[OVERULD]

Nicely done video. It made me want to buy the guy's car!

BJ

[SD73]

http://forums.maxperformanceinc.com/...d.php?t=612457

[superdutybob]

SD73

My point exactly!

[1971455HO]

Originally Posted by 74 SD455 Formula

I did the same thing with my 72 455HO GTO except I took off a Gardner system ( 2 1/4in ) and put on a R.A. restorations 2 1/2in "X" Pipe set up with the stock exhaust tipps and what a difference in performance.

Morning Guys. Please forgive my ignorance. I have a set of reproduction manifolds I bought a little over 20 years ago now. From everything I can tell, they're spot on identical to the originals, including part #'s and all. Sorry the box is long gone and I can't remember who made them, maybe Ram Air Restorations. They don't have the extra bolt holes like some of the newer ones do. I think mine are 2 1/4" outlet. I see all these cool exhaust out there for our birds but they seem to be for systems from the headers back. I'm not going to run headers.

My two questions are; Do any of these company's make complete systems from the stock manifolds back? Do they make them to fit the 2 1/4" manifolds and then expand to 2 1/2" the rest of the way back?

I'm hoping to get a complete stainless mandrel bent exhaust with all stainless hardware that fits like a glove. No beating, banging, bending or having to mount hangers where there never were any.

Please feel free to correct me in my ignorance. I'm all ears. Just following along here with your conversation made me think you guys have already been there and knew the solution.

Thanks, Eddie