455 swap maybe???

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1bad79

Royal Smart Person
Dec 3, 2011
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I know dyno tests have been done and shown 40 HP gains with full length headers on a W30 compared to W/Z manifolds and spindly stock duals. The early heads have a much smaller divider space to fill or mill compared to later junk 2A, 3A, 5A, 6A and 7A heads. I bet there will be an easy 20 HP gain with Sanderson 1 5/8" shorties, X pipe and 2.5" exhaust over the crappy SBO manifolds and 2" OD duals on my 70S. Run the BBO W/Z hi po manifolds, don't use the low performance regular manifolds if you want manifolds. Get the ones with the larger od exit and run 2.5" pipe.

I'm not saying they won't make more power, but for how cheap manifolds are and how easy they go in, and only a 20hp gain, the thorton manifolds imo would be a better choice for a DD. But if he wants headers, more power to him.
307, I have seen that some where to about the 40 horse gain but I have a hard time buying this. Typical header gain is dependent on the engine ,size,header length. One might see more torque gain down low with a small tube short header like the Sanderson but low on hp gain, but you might not be far off at 20, I would think 10, as far as price goes the manifolds from what I found are 50 bucks cheaper new v.s. the headers. I haven't personally seen either one but I found a old thread with a link that 307 posted in and a pic of the headers and the look nice and look like no hassle and a nice edition to a solid stockish build in my opinion
 

1bad79

Royal Smart Person
Dec 3, 2011
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Allendale mi
I forgot to include this manifolds were about 300 bucks ,sanderson headers were 355 bucks from what I found, your internet results may very
 
Oct 14, 2008
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It was Bill Travato who did the dyno testing, I believe the exact number was 39 HP and similar torque, I think. Shorty headers on most makes are right around 20 HP and torque, full length, 25 and up. I know the bolt on shorty headers for the 3.5 in my Challenger have produced 7 to 9 HP and 10 to 12 ft/lbs on the chassis dyno, according to guys before and after. I want a set, along with a ported throttle body and a Diablo tuner. The W/Z manifolds are much better than regular, awful manifolds, too bad they don't fit the SBO. The Thornton SBO manifolds need work to be better any real improvement. The problem with the Olds V8 and exhaust manifolds is the wide deck leaves little room. Of course the trade off is the wide intake with long, torque building runners.
 
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1bad79

Royal Smart Person
Dec 3, 2011
1,023
890
113
Allendale mi
It was Bill Travato who did the dyno testing, I believe the exact number was 39 HP and similar torque I believe. Shorty headers on most makes are right around 20 HP and torque, full length, 30 and up. I know the bolt on shorty headers for the 3.5 in my Challenger have produced 7 to 9 HP and 10 to 12 ft/lbs on the chassis dyno. I want a set. The W/Z manifolds are much better than regular, awful manifolds, too bad they don't fit the SBO. The Thornton SBO manifolds need work to be better any real improvement. The problem with the Olds V8 and exhaust manifolds is the wide deck leaves little room. Of course the trade off is the wide intake with long, torque building runners.
I probably read it in his book then,i dident know that about those manifolds that good info I've never looked in to those much or see them in person
 
Oct 14, 2008
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H/O84

Greasemonkey
Nov 29, 2016
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Not sure if OP is still thinking about buying that CL 455...just ran across it this morning and I wouldn't give $1500 for it
I wouldn't have given him $1500 for it been on CL for almost a month and wasn't willing to move on his price. I would have done $1000 at most on it.
I would have bought it, I hope he really did that deal, maybe he will chime in the car sounded like it had some good interior parts on it
I'm planning on going with that deal I told the guy I would give him another $50 to hold the stuff and he told me for $650 he wont sell it out from under me. Hopefully he won't but he seemed pretty trust worthy.
 
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Bar50

Royal Smart Person
Jan 1, 2009
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Tulsa, OK
The is the demographic I would be in. Any G-body parts can be sold pretty easy and quick around here, from low riders, to drag car. dirt cars, and guys just needing bones and parts.

I would get an Olds book. Used to be Mondello and Dick Miller were the Olds specialists. I like pump gas and lots of torque. So by definition, the combo doesn't need a really low gear, and will love an overdrive. Build a street/torque monster and enjoy.

For the record, from what I have seen for my 20 years of hot rodding, there are two basic Olds header shapes. If you don't mind some of the hassles they bring for the small offset in power thats cool, like lots of under hood heat, obviously louder, gasket failure, starter heat soak, etc. I would get a cam, timing set, and a dual plane intake....I noticed that the off shore guys make an Olds RPM Air Gap. I would look at a rocker arm conversion to use a SBC style arms or buy brand new rocker arms and trunions/pedestals. I wouldn't hesitate to slap on a 125 HP plate too, with a window switch that drops the timing back.

If the bore looks good, vat, hone, cam bearing and rings. Along with rods and mains. If its all together, at the least swap in some fresh gaskets and seals.

They are so much fun to drive, it makes you wonder why they did sell them that way.
 
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