1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought Home

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87vette81big

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Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

For what it would have cost for me to buy Moroso Intake manifold spacers plates & Weiland Stealth BBC Oval Port Intake new alone for the 427 Tall Deck BBC............
I bought a complete 1971 GTO 455 engine.
Minus Carb & exhaust manifolds.
I have them already.
I will use my 1965 Pontiac GTO Tripower once again too on this 455 Poncho.
Tripower flows 780 CFM. WOT sound roaring is priceless on a 455.
All Holy Hell breaking loose & being sucked in.
Only from a Poncho Big Block 3 Duece equipped.

496 BBC Grumpy wants me to build is $5-10 K away from reality.
New Garage more important still 1st.
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

first!
congrats on both the acquisition of the darn hard to find now, 455 Pontiac engine and posting the well done photos
.
viewtopic.php?f=44&t=4125&p=10957#p10957

http://www.hotrod.com/articles/474-hp-594-tq-495-inch-pontiac/
next,
as I'm sure your aware, after careful dis-assembly,an older engine that looks rather well used and un-loved and homely ,can look much different after a careful cleaning those parts will come out of a cleaning,wither you do it or have a local machine shop do it in far better condition and once cleaned and painted look like a totally different engine. personally Ive found the price of a 3200psi pressure cleaner, and particle blast cabinet, pays for itself very rapidly in what you save in cleaning costs you would have other wise spent at the machine shop.
(don,t forget to clean out the internal oil passages and replace the cam bearings and use brass freeze plugs)
sealedpower1220m.jpg

sealedpower3818021.jpg

EDL-2957_xla.jpg

edelbrocks # 2957 intake is a huge improvement over most available Pontiac 4 barrel carburetor intake designs

btw if you get the compression ratio up near 10.2:1-10.5:1 a cam in the 235-240 duration range on the intake with a .500-.530 lift RANGE GENERALLY WORKS WELL.
http://www.cranecams.com/product/cart.p ... il&p=24397
THIS CRANE HYDRAULIC ROLLER HAS WORKED WELL IN SEVERAL CARS WITH A 3.55 REAR GEAR AND 3200 STALL CONVERTER WITH EDELBROCK HEADS


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http://www.harborfreight.com/40-lb-capa ... 68893.html

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http://www.homedepot.com/p/Simpson-Hond ... 177499-_-N
 
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Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

I will clean all myself Grumpy.
Can't Rev this engine real high with pressed in Rocker Arm studs.
Can always convert to 1/2"-13 ----7/16-20 Top RA 4 Rocker arm studs I have.
Interesting it has Factory Dual Valvesprings.
Also has Pontiac PC -perfect circle positive Valvestem oil seals intake side.
.530" OD Guide tops.
Exhaust Guides should be cut same too.
Factory PC Seals used on 1969-70 RAM AIR 3 &4 &5 Along with 71-72 455HO & 73-74 SD-455 only.
Ditto for Dual valve springs.
SD 421 Had special dual valvespring package also.

Otherwise single spring with damper.

Looked up 66 Heads. Not too bad of flow as is.
Close to RAM AIR 3 Specs.

Definate a GTO Engine 71 455 & not a Full size car engine.
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

I have to take inventory of what I have on hand to get this 455 ready.
Should have almost all.
Need my cleaning solvent & brake cleaner supplies.
NOS SD455 Oil pan going on.
WORK ON MY 12-Quart AMMO Pan for it later this fall.
Easy getting Pontiac pan off in 63 GP.
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

Not getting real radical with this 455 Grumpy.

I have another 455 . From a 1970 Bonneville convertible.
360 HP & 500Ft/lbs Rated stock.
Saving it for New TA Engine build. 1970 455 Block is only I will use.
Didn't want use in 63 GP.
1970 Block & Crank to match my 1970 TA. Pontiac guy Superstitions...
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

knock out the gp first man, then strt planning your attack on the trans am... my problem is always been having so many projects going on and not having fun with anything because everythings under construction... dont be like me
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

philly said:
knock out the gp first man, then strt planning your attack on the trans am... my problem is always been having so many projects going on and not having fun with anything because everythings under construction... dont be like me
I am like You Phil.

I just said the hell with the Vette for now.

Pick the easiest project & lowest cost $.
Make it look nice & functional.
Stay away from Billet Aluminum shine parts.
Don't make your car any faster.
Just run out of money.
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

87vette81big said:
Not getting real radical with this 455 Grumpy.

I have another 455 . From a 1970 Bonneville convertible.
360 HP & 500Ft/lbs Rated stock.
Saving it for New TA Engine build. 1970 455 Block is only I will use.
Didn't want use in 63 GP.
1970 Block & Crank to match my 1970 TA. Pontiac guy Superstitions...

I bought a 70 B'ville once because it had the 455 and I thought it'd be great to put a 70 455 in my 70 bird. Next day I got offered double what I had in the B'ville with towing etc. So off it went! I saw it a while later with wide whites curb feelers etc. ahahaha Eventually I'll probably go stroker 400 for the bird.

Congrats on the 455 for the GP!
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

NOT A TA said:
87vette81big said:
Not getting real radical with this 455 Grumpy.

I have another 455 . From a 1970 Bonneville convertible.
360 HP & 500Ft/lbs Rated stock.
Saving it for New TA Engine build. 1970 455 Block is only I will use.
Didn't want use in 63 GP.
1970 Block & Crank to match my 1970 TA. Pontiac guy Superstitions...

I bought a 70 B'ville once because it had the 455 and I thought it'd be great to put a 70 455 in my 70 bird. Next day I got offered double what I had in the B'ville with towing etc. So off it went! I saw it a while later with wide whites curb feelers etc. ahahaha Eventually I'll probably go stroker 400 for the bird.

Congrats on the 455 for the GP!
Thanks '70 Bird Man.
200 mph to be set by You.!!!!
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

The Fel Pro Pontiac #2806 Race Gasket sets came in today Grumpy.
2 sets.
Few more parts bought & coming.

Hard parts have gone up tremendous .
About 3 times more in just the last few years.

No china crap.

All Made in the USA.
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

The stock cast iron #66 Heads are very good as is Grumpy.
Researched more.
They Nearly match the 1971 HO 455 Round Exhaust port 197 heads in flow.

Outflow the Highly prized 670 Ram Air 1 '67 GT0 Heads.
#62 Heads.
#48 &12 '69-'70 Ram Air 3.

Flow as well as the 1963 Pontiac SD421 Heads #980's.
But 980's have perfect balanced Exhaust to Intake ratio at all lift points.

The 66 Pontiac heads I have shine in the .300-.500 Lift Range.
Keep flowing at .600 Inch lift.
Exhaust to Intake Ratio of .74 , not too bad.
Perfect match with stock installed 067 Cam now.
068 Will work nice too.
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

I found lots of Modern & Vintage Pontiac V8 Race info on my own lately Grumpy.
Some I knew of & a few new.
Pontuac had the 1st factory 10-second Car.
1963 AFX Super Duty 421 Tempest.
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

grumpyvette said:
if you found anything about building Pontiac, engines ,thats interesting and useful please post as much as you can here on the site
I will Grumpy.
At work now.
Roger Huntington Vintage articles the best. Still searching for them.
Famous writer & tester.
He loved Pontiacs too.
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

Engine Teardown & Inspection Sunday afternoon into the evening hours.
Its a Good Poncho 455 :mrgreen:
Mint perfect standard crankshaft & the good nodular iron piece.
Cylinder bores may hone clean. Have to dial bore gauge check. \
Inside of engine exceptional clean for 43 years old.

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Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

yeah! it appears you got a real gem! its darn rare to find an engine from that era in that excellent condition, so as I'm sure your aware youll need to keep it clean and all machined surfaces coated with oil if you wanted to keep it that way.
so many guys see an older engine with external rust and flaking paint and greasy dirt and don,t realize that is just easily,
removed outer covering, that must be removed to see the inner beauty, kind of like putting a playboy bunny in a fire suit, and trying to judge whats inside
so many guys judge from initial appearances
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BTW GREAT ENGINE PICTURES
 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought


Impressive how clean the bottom of the oil pan was, absolutely no sediment!

 
Re: 1971 Pontiac GTO 455 RPO L-75 325HP & 455Ft/lbs Brought

I sprayed the entire engine block & crankshaft with CRC All Purpose oil & rust preventive before I left for work this morning.
In my basement on the engine stand & air conditioning on.
Its real humid & hot in Illinois now. Rust on bare iron otherwise.

Wipe it all down tonight time permitting.
Knock the freeze frost plugs out & remove oil gallery plugs.
Calibrate my Micrometers, Calibrate my Cylinder dial bore gauge & get out my new new Snap On 36" inch long machinist straight edge.
Inspect & measure all.

Like to reuse the factory 1971 GTO pistons.
Stock compressuin height on 455 pistons have a near zero deck height assembled.
Maybe .002-.005".
Great quench area with Fel Pro 1016 Pontiac Race headgaskets.
.039" compressed.

If needs overbore I have a new set of Keith Black Pontiac 455 pistons Hypers put away.
Use my new Crower Custom made Forged rods for Pontiac 455.

1970 455 I have also will get the Crower Ti ultralight extra long rods.
Need special custom made pistons with one off compression height distance to use them.
Diamonds... $1k only for those..... :)
 
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