1963 Grand Prix

2nd question - are those
Long Branch Exhuast Manifolds ? #9779494 & #9779495, they fit 1965-68 Full Size Pontiac with the 421 & 428 HO engines. These are a D-port manifold. Will they fit my Cat?3D03797F-5E10-475C-A959-4015D415CA42.jpeg
 
they are cylinder head porting stands ,
you must have skipped reading a few thread links:D:rolleyes:
http://garage.grumpysperformance.com/index.php?threads/porting-can-help.462/page-2


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https://www.amazon.com/Moroso-62080...t=&hvlocphy=9012039&hvtargid=pla-568921332166
https://www.summitracing.com/parts/pow-pow351410
btw there are much better versions
https://www.amazon.com/PROFORM-6648...dp/B001G9A63K/ref=psdc_15725931_t3_B000COS59M

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https://www.proformparts.com/produc...adjustable-heavy-duty-model-supports-one-head
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Ok, I have some questions. Are all aftermarket cams etched? I’ve been wondering if my sbc motor that I know was rebuilt by the last owner - upgraded the cam at that time. I don’t want to take it apart unless I have good reason to believe info could be there.
They usually are .
Have to pull the cam out or the engine often to verify.
Or remove the Rear camshaft plug on the block.
 
I bought the Moroso stands.
I look at Feedback on Summit Racing on items left by others.
Seen they hold up great to Cast iron Big Block Chevy heads Porting away.
They are Super strong rigid and priced right. Fit my needs perfect.
 
yeah, I found they work, but I found when I port heads,
I can bolt two old used flex plates,
http://garage.grumpysperformance.com/index.php?threads/porting-can-help.462/page-2

http://garage.grumpysperformance.com/index.php?threads/porting-can-help.462/

http://garage.grumpysperformance.com/index.php?threads/porting-can-help.462/page-3
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one of two identical flexplates bolted on each of the cylinder head,
to the ends and have two parallel 2 foot lengths of 2" angle
about 3" apart that allow you to set the heads at any angle
yeah the heads do need to have accessory mount holes,
and yeah in a few cases you need to drill one hole in the flexplate,
but you can still use the flexplate for its intended use if you have it
mount the flexplate the same on both ends and as close to centered as
practical
remember good lighting and a vacuum helps and keep the burr on the die grinder burrs clean and use wd 40 to limit aluminum clog issues
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WEARING A FULL FACE SHIELD and having a 5-6hp shop vacuum set up to suck the vast majority of the debris from the porting work out of the air is going to help prevent some accidents and getting crap in your eyes
high pressure air and some carb cleaner solvent can be very helpful cleaning out sticky or dirty parts
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A few I recall most experienced built custom Porting stands like a Rotisserie infinite adjustable and locks.

The short turn radius is difficult to see, I had to use my index finger, feel visualize in my mind.
When you change the bowl area Enlargement, you must rework the short turn radius, have a new restriction left.
 
The reason I ask about the exhaust manifolds - I believe I have a set somewhere. Yes, it’s true, it’s my mental defect :eek:
I bought them thinking that the 421 and 428 is the same on the exterior dimensions and the heads have to be the same bolt up configuration and so on. If it’s ok on a 421 Bonneville 1968 it should fit right. I just anticipate the exhaust pipes won’t be in the correct places so they need to be worked up.

What do you think in terms of Torque and hp with a pair of long branch manifolds? Same as aftermarket headers? I would think they are quieter, won’t hear the valve train.
 
The reason I ask about the exhaust manifolds - I believe I have a set somewhere. Yes, it’s true, it’s my mental defect :eek:
I bought them thinking that the 421 and 428 is the same on the exterior dimensions and the heads have to be the same bolt up configuration and so on. If it’s ok on a 421 Bonneville 1968 it should fit right. I just anticipate the exhaust pipes won’t be in the correct places so they need to be worked up.

What do you think in terms of Torque and hp with a pair of long branch manifolds? Same as aftermarket headers? I would think they are quieter, won’t hear the valve train.
They can support 500+ Hp.
Mine I had to Port match alot.
Well.made from Ram Air Restoration in Round Lake Illinois.

Originals difficult to find.
Worth $$$.
Best used on SD421 they are cast Aluminum. Reproduced also both expensive.
Original survivor SD421 worth near $5k.

They were used 1959 to 1970 on special engine packages only.
Some daily driver high output engine like the 420A and 425 A Trophy 389.
Later Tripower 421.
428 390 Hp.
455 H0 1970 Grand Prix 370 Hp.
Also a few 1970 Pontiac Bonneville Hardtops surfaced with 455 HO 370 Hp , 3 of them so far.
 
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Long branch will not work well with True Race Race Cams , if I had used one with long tube Headers, It would be well over 650 Hp the 1976 455 engine.
It's been done just 8.4:1 iton heads ported like mine.
Headers for 63 Gp were made by Mad Dog Headers, discontinued few years ago.
He wont make them again.
1st Generation Firebird headers Hooker Super Comps will fit with some work, 1 off Tig welding done, Need my friend Eddie to do it his garage.
Its actually nice not having to worry about smashing up header tubes driving.
Problem always in 70 TA.
Had to be careful always .
Gp just fire it warm up and go.
 
Also why I chose a mild cam Isky 232 @.050.
Isky 280 Mega.
Did engine simulations with target 6500 rpms max for Street with ported heads targeted airflow.
Used Pete Mc Cartys Head Porting video to get started, race math all there in it.
I can not share the video, its Copy writen.
Pete is still alive, also a Pontiac legend Hero.
Do him injustice and breaking Federal law sharing his video, have to buy it yourself
 
OK, why is your timing wrapped in aluminum foil?
You're not wearing an aluminum hat are you? :rolleyes:
I think I should get one myself.
Big brother and the space aliens are watching.........
 
OK, why is your timing wrapped in aluminum foil?
You're not wearing an aluminum hat are you? :rolleyes:
I think I should get one myself.
Big brother and the space aliens are watching.........
RFI Radiation from the Vertex Magneto.
It's so hot of a spark.
Better than the Vintage MSD 10 AL Racing box that costed $1000 in the 1990s used by Pro Stock.
Found the trick so my Digital readout timing light works reads accurate no RFI Interference.
Wrap it in tinfoil there is a Computer inside.
Hook up onto the Magneto #1 wire by cap .
Not at the spark plug.
 
I just found the receipt for the long branch headers, I paid $600 for them, no cracks, no welds. I put new studs in them when they came in. I missed dropping the Cat off at Mieneke tonight for early morning install of the new exhaust system. They wanted it parked inside over night to avoid a hot car in the morning.

I must install the tilt steering column SAP, it’s a major pain in the ass to drive with a fixed position 16” wheel.
 
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