Guess the HP

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MinnesotaMopar said:
My mistake, I thought it was an 850 CFM carb. Well then I'll adjust my total HP guess up to
630 at 6,100 rpm, with the torque still 610 at 4,400 rpm.

Now I think your limiting factor will be the cam duration. You will prably be able to spin it up to 7,000 if you wanted but you will need a bigger cam to make more power at the higher RPM. Nevertheless 1.3 hp per cubic inch is a very respectable amount of power from a 60 year old wedge head design. As Rumblefish360 said it is never enough. And there is always something you can change to get more power.

As for me that is the fun part of a NA engine, searching for that next thing to improve to get more HP. For the turbo guys it is simply a matter of turning up the boost or the NOX guys just bolt on more and bigger injection nozzles (and hope it holds together).

I'm glad to see you are going the NA route, but as you already know, that is the hard way to make power. (but the more satisfying way I think)

The next thing is going to be getting all this power into the track, and chassis tuning can be a new set of challenges. Will you tell us about the car you will be putting this into?
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Yeah ,so far 70 dart, 12 pt cage (uninstalled yet)
Very narrow Dana 60 with caltrac split mono leafs, assassin bars, for now caltracs adjustable rear shocks. 90-10 up front with slant 6 torsion bars. For now body panels are steel. Tires are hoosiers 29.5 11.5 w 15 on 15 by 12 weld wheels. Front weld skinny
 
@PHR @crackedback If you guys could tell me, because I’m a little younger, what, if any headers were available for the A bodies that were not fender well exits back in the ‘70’ & 80’s?

I just don’t know and seriously ask.

When I was I. High school, early ‘80’s, at the track I only seen fender well headers on big block Dusters.
crackedback said:
Pass time was awesome for the overrated underperforming hp cars.

Some of the magazine stuff with 800hp engines in 3200# cars and not even getting 120mph in the 1/4. Yeah, not close to making that power!

Agree with PRH, the fenderwells, especially Hookers will hurt the engine up top. BTDT
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rumblefish360 said:
@PHR @crackedback If you guys could tell me, because I’m a little younger, what, if any headers were available for the A bodies that were not fender well exits back in the ‘70’ & 80’s?

I just don’t know and seriously ask.

When I was I. High school, early ‘80’s, at the track I only seen fender well headers on big block Dusters.
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Castler
black jack
doug thorley
headman( I think)
Cyclone
believe Mazzolini might have offered some, maybe
 
B3422w5 said:
Castler
black jack
doug thorley
headman( I think)
Cyclone
believe Mazzolini might have offered some, maybe
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Offered in the ‘70’s & ‘80’s?
Cool, thanks.
Never heard of Castler.
 
pittsburghracer said:
www.castleheaders.com.au
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think that is a different company……

post from Don Terrill’s speed talk that popped up when I googled Castler headers 1970’s…

“It's been years thinking anti-reversion was dead until I saw this thread. In 1979 I came up with the idea, built some headers and tested it. Next was trying to patent it. At the time, here in Canada, you couldn't patent an idea. The patent application was to protect yourself for one year while you set up production and distribution. So, since I didn't have the $1Mil. to set up production, I tried selling the concept to header companies I was dealing with; Hooker, Doug Thorley, Castler, Cyclone and Hedman. No one was interested.
6 months later, my wife comes running into the room crying and showed me a CarCraft magazine and on the cover page was; Hedman”
 
one of the 2 head a slip fit tube off the head i think it was black jack or cyclone on the drivers side
 
I had a set of headers on a 69 340 GTS that I bought in 1972, but for the life of me don’t remember what brand they were, think Blackjacks, they were well under 100 bucks. Had thrush muffs hanging off them
 
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hush thrush cost 9 bucks then i think the blackjackss where 59 i think from midwest
yup iam old
 
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B3422w5 said:
I had a set of headers on my 69 340 GTS that I bought in 1972, but for the life of me don’t remember what brand they were, think Blackjacks, they were well under 100 bucks. Had thrush muffs hanging off them
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$39.99 lol
If you had a big block A-body in the late mid 70's /80's. most using headers had Hooker FW, mine cost $ 150 in 79.
 
a-bodyguy said:
hush thrush cost 9 bucks then i think the blacks where 59 i think from midwest
yup iam old
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The thick Midwest catalog? I ordered a bunch from them. Whatever happened to them? name change?
 
think taken over
1st with 800 tel number
1 800 take all my money
 
LOL! That great. I paid, *I Think* it was $89 for my blackjacks for my Duster. That would be ‘85/‘86…. *I Think!*
They were aluminum coated? Color was white and texture was rough.
I used 2-1/2 pipe into some “Sonic Turbo” mufflers. It ended at the axle. Thunderous sound from a 318! LMAO!
 
Well guys, no numbers yet.
We did get it fired up and got a heat cycle into the headers. So far I grinning eat to eat it sounds awesome to me. Hopefully I'll have a video tomorrow, with the results.
 
PRH said:
My experience with the fenderwell headers is they peak pretty early. They improve the numbers below peak TQ, and can show a slight gain in the peak TQ value.
But they didn’t carry the TQ all that well past peak, and as a result...... the HP number suffers.

On the dyno here, with those headers........ I’d be expecting solidly over 600TQ, and maybe 625-635HP...... if the curve hangs on well enough.

Edit- after looking at an old test with a 493 and FW headers, the 625-635hp might be a bit generous.
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Funny you say that, I was surprised that my engine peaked at 5,900, especially with the 112LSA. I used 2.125 fenderwell headers on the dyno, but TTI 2" in the car. At the strip it did best shifting at 6,200.
 
Didn't the CPPA big block A body headers come out in the early 80's?
 
493 with std port SR’s, M1 single plane w/4500 adapter, 1050 carb, 11-ish CR, roller cam.

FW headers:
618tq@4100
639tq@4500

638hp@6100
616hp@6800

2-2 1/8 x 4 dyno headers:
518tq@4100
637tq@4800

673hp@6300
665hp@6800

The crossover point was 4700rpm.
Both were 567hp@4700, then the dyno headers just pulled away.
FW headers were 100tq better at 4100.
 
PRH said:
493 with std port SR’s, M1 single plane w/4500 adapter, 1050 carb, 11-ish CR, roller cam.

FW headers:
618tq@4100
639tq@4500

638hp@6100
616hp@6800

2-2 1/8 x 4 dyno headers:
518tq@4100
637tq@4800

673hp@6300
665hp@6800

The crossover point was 4700rpm.
Both were 567hp@4700, then the dyno headers just pulled away.
FW headers were 100tq better at 4100.
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Because of the too-long tubes, the too-small tubes, or both?
Curious, cause I have a fenderwell header car with no room for under chassis version.
 
It was 20 years ago.
Cam was 270’s @.050, .660 lift.

My notes say the FW headers were 2 x 3.5.

I’d say the length was the big player there.

The FW headers were what was used in the car.

This was a job where the motor was updated from a 446 to a 493.
I basically just replaced the rotating assy and used a different cam.
The 446 combo had a Comp 306R-8, .625” lift.
It was a combo he bought from MM.

With the FW headers it made:
513tq@4100
532tq@4800

551hp@6500
548hp@6800

In the car, with the extra cubes it went almost 1 second quicker in the 1/4.
No changes were made to the car.
 
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a-bodyguy said:
hush thrush cost 9 bucks then i think the blackjackss where 59 i think from midwest
yup iam old
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Yep I had a set on my 1972 duster way back when. I still have the 1/4 inch horseshoe shims I used on my motor mounts to give me a little more clearance. They were 59.00 for a long long time. That and the deal they had on tunnel rams and 600cfm Holley carbs. Lol
 
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