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Author Topic: Pontiac 400-455 Questions and answers. Subthread  (Read 166964 times)

cspella

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #80 on: September 24, 2008, 12:40:38 PM »
so im new to the pontiac world i just bought a 76 trans am with the 400. the numbers i have gotten off the internet lead me to believe the engine is as strong as i may need what can be done to up the power

Doug

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #81 on: September 24, 2008, 12:45:52 PM »
so im new to the pontiac world i just bought a 76 trans am with the 400. the numbers i have gotten off the internet lead me to believe the engine is as strong as i may need what can be done to up the power

Exhaust, cam and heads would be the first order of business

Mr. P-Body

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #82 on: September 27, 2008, 11:42:10 AM »
cspella,

   Get Jim Hand's "How to Build Max-performance Pontiac V8s", published by SA Designs. This has been mentioned in earlier posts, but always needs to be "re-mentioned"...  It is the only CURRENT  study of the Pontiac V8.  It's intended for high performance street engines, and not intended for a true "race" engine.

   '76 400s were complete "smogger" engines. Dramatic power gains can be had by changing a few key pieces. If it's original, it's time for a rebuild and those changes can be made more easily during that rebuild. It's no problem at all to get 350-400 HP on 93 octane fuel and still use the stock converter and rear gear.

  If you need more specifics, just say so!

Jim

Bandit 77

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #83 on: September 30, 2008, 12:19:16 PM »
any ever replaced the dip stick tube and guide that attaches to the #3 main cap.  mine is missing so any pick on what it looks like and excally how it bolts on would be greatly appricated.
74 Formula  462 auto (455 .030 over)
77 Trans Am 455 6 speed project
78 Trans Am 400 4spd (parted and sold)
79 Formula 400 auto (Sold)
79 Trans Am 403 auto Y84 SE
09 G8 GT 6.0 auto
Z.E.D.U. #800 motor pool

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Tony79WS6

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #84 on: September 30, 2008, 12:32:27 PM »
any ever replaced the dip stick tube and guide that attaches to the #3 main cap.  mine is missing so any pick on what it looks like and excally how it bolts on would be greatly appricated.

I just went through this on my 400 recently. First off, and not to scare you, but you're probably going to have to yank the motor to do this. If you've already done this, then you'll need this:

It's the one with the tab coming off of it. You'll also need this:

This one gets pressed into the dipstick hole. I slightly pressed in the outer one first and then installed the bottom part that attaches to the main cap. It bolts on with 2 bolts attached to the cap. Then, I pressed the top in until it met the bottom tube.   

Where did the old ones go?
-1979 WS6 T/A

Bandit 77

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #85 on: September 30, 2008, 06:49:14 PM »
dunno, they werent there when i repaced the main bearings and having never been in the bottom of a pontiac motor didnt know they were spose to be. long story short i noice a cut off dip stick and figure i would replace it when i was done, first time i fired up the motor it shot the new dip stick right out from under the hood.
74 Formula  462 auto (455 .030 over)
77 Trans Am 455 6 speed project
78 Trans Am 400 4spd (parted and sold)
79 Formula 400 auto (Sold)
79 Trans Am 403 auto Y84 SE
09 G8 GT 6.0 auto
Z.E.D.U. #800 motor pool

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OriginalHO

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #86 on: October 01, 2008, 04:58:47 PM »
BTW, there was an early question in this thread about bolt size at the back of the block to attach an engine stand or bell housing.  At least 1963 (which I recently assembled) had 7/16 NC, not 3/8 NC.  Does anyone know what year Pontiac changed that? 

It surprised the heck out of me, although I did some work on real early blocks, but that was too long ago and I didn't remember that difference.  Fortunately, I had  a set of 7/16 NC grade-8s for my engine stand that I had used on my Packard V-8s.

Regardless of size, be sure to use grade-8, not grade-5 (hardware store variety).  You wouldn't want that fully assembled engine dropping on the floor -- or your foot -- would you?
Craig Hendrickson, the "H" in H-O Racing Specialties, Inc.
http://www.OriginalHO.com

Mr. P-Body

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #87 on: October 02, 2008, 11:52:42 AM »
Craig,

   Regarding the bolt size "change"...

   '64 A-body engines had the 3/8 bolts, B-body cars still used the 7/16. It's the same "line" as the starter change from bellhousing to block.

Jim

LeighP

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #88 on: October 05, 2008, 11:13:12 PM »
dunno, they werent there when i repaced the main bearings and having never been in the bottom of a pontiac motor didnt know they were spose to be. long story short i noice a cut off dip stick and figure i would replace it when i was done, first time i fired up the motor it shot the new dip stick right out from under the hood.

lol, until my friend pulled his 428 apart, he had to keep a broken off dip stick in the tube while driving the car, and a complete dipstick on the shelf at home for dipping the oil...same problem, no bottom piece on the tube....lol.
Regards,
Leigh

Sydney, Australia
1968 Pontiac Firebird 428 5 speed coupe

Former Firebirds -
1969 Pontiac Firebird 400
1971 Pontiac Firebird 455
1977 Pontiac Trans Am
1976 Pontiac Trans Am
1967 Pontiac Firebird 400 convertible
1967 Pontiac Firebird 400 coupe


72blackbird

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #89 on: November 25, 2008, 12:45:53 AM »
I'm overhauling/ upgrading a 350 I bought recently, and decided to mount a 4/5 windage tray on it- the lower dipstick tube is the one that has a mounting tab on it. I ordered the interference fit version (wedges between the block and tray) from Parts Industries for $19.99- thought that was expensive until I priced the OEM part at the dealer ($50).

Geno
1977 SE T/A (sold :( )
1974 455 T/A (sold :( )
1972 Esprit restomod
1976 T/A restomod
1975 Formula 400 4-speed donor car
1978 Martinique blue W72 4-speed T/A, hurst tops

MacGyver

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #90 on: February 16, 2009, 10:59:24 PM »
The wife bought a 78 Gold Ta last year thats shes been meaning to work on... well.. after driving it until the tranny went out, its now sitting in the driveway starting its work.  This is both of our first "old" car.  Anyway, its had some extensive "rigging" in its past, so lots of baack tracking is in order for this poor car... the engine will be pulled out of it fairly shortly to give it a minor overhaul (new gaskets, clean it out, etc) where we can get a better look at the numbers, etc. as we know its not the original motor.  But from what we can see with it in the car..

481988 block casting YX code
K011 date

Which from what I can tell, is a 400, dated November 1, 1971 with 265hp... but I could be wrong as there is a TON of numbers for these engines..

So first question would be, is there anything to look out for, or make sure we do when it gets pulled and new gaskets put in to make this engine perform well?  We aren't looking to rebuild or upgrade at this time as funds don't allow right now.  Any and all info/direction/hint/etc would be helpful with this.  Thanks.
-Geno
1983 Black Trans Am "Wind Charger"
1985 Blue Camaro "TransMaro" (sold)
1985 Brown Firebird (sold)
1987 Black Trans AM "Project WS87"
1988 Blue Formula (sold)
1997 Green Z28 (sold)
2002 Black T/A WS6 "Silver Streak"

MacGyver

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #91 on: February 17, 2009, 05:47:14 PM »
Was out finishing the removal of the rear, and looked under the hood again, and saw a couple numbers listed on the driver side head just below the valve cover..

D <-- N  71    G070

I would imagine the D and N are for DAy and Night shift, thus being DAy shift... but the 71 and G070 haven't come up with any info yet.. I am not able to see any numbers on the pass side yet as the engine is sitting far back (only on the motor mounts) and can't see past the accessories.

And on the Driver side Manifold, there is 1 <-- 2  E197 (could be E107)

Ideas?
« Last Edit: February 17, 2009, 05:50:10 PM by MacGyver »
-Geno
1983 Black Trans Am "Wind Charger"
1985 Blue Camaro "TransMaro" (sold)
1985 Brown Firebird (sold)
1987 Black Trans AM "Project WS87"
1988 Blue Formula (sold)
1997 Green Z28 (sold)
2002 Black T/A WS6 "Silver Streak"

Clint S

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #92 on: February 17, 2009, 07:54:13 PM »
G070 could mean G=7th month July 07  0=1970
72 Firebird Esprit 455
Get high on milk, my cow's on grass.
http://i198.photobucket.com/albums/aa72/stelmashuck/103_0567.jpg

MacGyver

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #93 on: February 17, 2009, 08:01:15 PM »
G070 could mean G=7th month July 07  0=1970

Yeah, thats what we just found.. and we also found 94 on the bottom of the head near the exhaust.. which from what I have found are 1971 350 heads?!?!  Would/could this pose a problem? 

We have found LOTS of discrepencies with this car, as the driver door is different, so no codes from there, the engine and tranny are from a different car, etc.. so we are finding one thing after another that make us want to tie up and skin the previous owers and let the animals have their way with them.. .:mad:
-Geno
1983 Black Trans Am "Wind Charger"
1985 Blue Camaro "TransMaro" (sold)
1985 Brown Firebird (sold)
1987 Black Trans AM "Project WS87"
1988 Blue Formula (sold)
1997 Green Z28 (sold)
2002 Black T/A WS6 "Silver Streak"

Clint S

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #94 on: February 17, 2009, 08:12:28 PM »
I think 94 heads are like 96 cc so it would be fine on a 400 probably around 8 to 1 compression.  They would be a good head for a 455 8)
72 Firebird Esprit 455
Get high on milk, my cow's on grass.
http://i198.photobucket.com/albums/aa72/stelmashuck/103_0567.jpg

Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #94 on: February 17, 2009, 08:12:28 PM »


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72blackbird

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #95 on: February 18, 2009, 01:43:42 AM »
The no.491988 400 block is a good block to use for a performance buildup (thicker casting than the weaker no.557 blocks), so you're golden there. Pontiac V-8's all come from the factory with flat top pistons for the most part, compression comes from the combustion chamber volume of the heads. You're correct in your number search for your heads- the no.94's had 96 cc chambers, 1.96/1.66 valves- about 8.3:1 CR on your 400. These are decent heads for a stock motor, or even a mild build up.

I wouldn't stress out too much about the numbers deal - you can find numbers-matching cars still but you will have to pay for it unless the seller isn't aware or doesn't care.  And since the car clearly isn't a numbers matching car, it's perfect for a performance buildup.

Geno
1977 SE T/A (sold :( )
1974 455 T/A (sold :( )
1972 Esprit restomod
1976 T/A restomod
1975 Formula 400 4-speed donor car
1978 Martinique blue W72 4-speed T/A, hurst tops

Rick

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #96 on: February 18, 2009, 08:19:33 AM »
Pontiac V-8's all come from the factory with flat top pistons for the most part, compression comes from the combustion chamber volume of the heads.

One caveat there -- the 75/76 engines (at least, maybe into 77) had "chamfered" pistons in them which dropped the static compression ratio from the usual 8:1 to about 7.6:1.  The "chamfered" was basically just the outside edge of the piston which added enough end volume to drop the SCR 0.4 point.  If anyone has questions about how the two compare I can post them.

BoDarvelle

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #97 on: February 24, 2009, 09:39:33 PM »
There is a hint that will save you 300 bucks.

The Dip Stick on a Pontiac is installed from the inside of the block. Not from the outside after the darn engine is already installed in the car!!!!

BTW thanks to Jim Butler for making me laugh while telling me what a dumb-ass I was for not knowing that. He is one funny guy.
Home of the Trans-Am you cant pass or catch!!


MacGyver

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #98 on: February 24, 2009, 10:26:17 PM »
There is a hint that will save you 300 bucks.

The Dip Stick on a Pontiac is installed from the inside of the block. Not from the outside after the darn engine is already installed in the car!!!!

BTW thanks to Jim Butler for making me laugh while telling me what a dumb-ass I was for not knowing that. He is one funny guy.
:confused:  You wanna run that past me again?
-Geno
1983 Black Trans Am "Wind Charger"
1985 Blue Camaro "TransMaro" (sold)
1985 Brown Firebird (sold)
1987 Black Trans AM "Project WS87"
1988 Blue Formula (sold)
1997 Green Z28 (sold)
2002 Black T/A WS6 "Silver Streak"

BoDarvelle

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #99 on: February 25, 2009, 08:56:54 AM »
There is a hint that will save you 300 bucks.

The Dip Stick on a Pontiac is installed from the inside of the block. Not from the outside after the darn engine is already installed in the car!!!!

BTW thanks to Jim Butler for making me laugh while telling me what a dumb-ass I was for not knowing that. He is one funny guy.
:confused:  You wanna run that past me again?

The dip sitck tube on a 455 is pressed in from the inside of the block. If you build the whole engine and install it in the car and then try to put in the tube you have to pull the pan to install the tube. :)
Home of the Trans-Am you cant pass or catch!!


MacGyver

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #100 on: February 26, 2009, 08:19:27 PM »


The dip sitck tube on a 455 is pressed in from the inside of the block. If you build the whole engine and install it in the car and then try to put in the tube you have to pull the pan to install the tube. :)

Ahh.. ok.. that makes sense now.  Sorry for your misfortune.. but you won't make that mistake again..
-Geno
1983 Black Trans Am "Wind Charger"
1985 Blue Camaro "TransMaro" (sold)
1985 Brown Firebird (sold)
1987 Black Trans AM "Project WS87"
1988 Blue Formula (sold)
1997 Green Z28 (sold)
2002 Black T/A WS6 "Silver Streak"

MacGyver

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #101 on: March 10, 2009, 02:21:41 PM »
Well.. tore a little more into the engine and found these numbers...

481988 block casting YX code
Engine Unit Number 0079409
K011 date (Nov 1, 1971)
Engine Cast number 0234013 (above XY)
Engine VIN: 22P317551

So with the casting date, code, number and partial VIN show that its a '72.
We found the 400 found on the bottom which proves its a 400.
What does the engine cast number (0234013)and engine unit number (0079409) tell us?
And with the VIN, the 2 is Pontiac, the 2 is for 72, the P is for the plant (which one, and what did they produce.. for what cars?)

Any idea what heads would have come on this engine, as we don't believe the 94 heads came stock on it?

As said they would be good for a stock engine/mild build.. what SHOULD we be looking for in the future?

We are just trying to knock down as much about this car as possible.. just too bad we can't tell exactly what the engine came from..
Thanks everyone.
-Geno
1983 Black Trans Am "Wind Charger"
1985 Blue Camaro "TransMaro" (sold)
1985 Brown Firebird (sold)
1987 Black Trans AM "Project WS87"
1988 Blue Formula (sold)
1997 Green Z28 (sold)
2002 Black T/A WS6 "Silver Streak"

TreySmith

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #102 on: July 17, 2009, 07:16:10 PM »
How much HP can I safely make on my 78' 400? I want to turbo my motor, then get forged rods and pistons down the road before I turn the boost up. But completely stock what is the HP mark that I shouldn't cross?
79 Blazer- sold
94 Camaro- sold and cut up for parts
95 Camaro- sold
70 GTO- sold and cut up for parts
80 S/E T/A- sold
Two 69' fastbacks- Someday
99 WS6 6 Speed- Daily Driver
73 Camaro-current project
70 Charger next in line..

Clint S

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #103 on: July 18, 2009, 07:47:14 AM »
What s the block code.  Is it a 557 or a 988.  I believe no more than 500 with a 557.
72 Firebird Esprit 455
Get high on milk, my cow's on grass.
http://i198.photobucket.com/albums/aa72/stelmashuck/103_0567.jpg

TreySmith

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #104 on: July 20, 2009, 06:00:50 PM »
Where do I find the block code?
79 Blazer- sold
94 Camaro- sold and cut up for parts
95 Camaro- sold
70 GTO- sold and cut up for parts
80 S/E T/A- sold
Two 69' fastbacks- Someday
99 WS6 6 Speed- Daily Driver
73 Camaro-current project
70 Charger next in line..

Clint S

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72 Firebird Esprit 455
Get high on milk, my cow's on grass.
http://i198.photobucket.com/albums/aa72/stelmashuck/103_0567.jpg

TreySmith

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #106 on: July 23, 2009, 06:34:03 PM »
What are the "good" years for these engines? I want to make a turbo for my car or stroke it and forge the internals. Is it 70-75? I found a 74 on craigslist and want to make sure before I look at it.
79 Blazer- sold
94 Camaro- sold and cut up for parts
95 Camaro- sold
70 GTO- sold and cut up for parts
80 S/E T/A- sold
Two 69' fastbacks- Someday
99 WS6 6 Speed- Daily Driver
73 Camaro-current project
70 Charger next in line..

Clint S

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #107 on: July 23, 2009, 07:06:49 PM »
The 70 through 74 are the 988 codes, BUT  the 77 and 78 w72's were also 988 codes.  best bet is to look at the code.  The other thing is is that with nitrous you probably want a 4 bolt main which are sort of rare (  I think only the RA engines were, but I am no expert :-?0  on the 400's so you may want to have your block drilled and tapped and get a set of caps
72 Firebird Esprit 455
Get high on milk, my cow's on grass.
http://i198.photobucket.com/albums/aa72/stelmashuck/103_0567.jpg

ayers1981

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #108 on: September 08, 2009, 06:59:51 AM »
The 70 through 74 are the 988 codes, BUT  the 77 and 78 w72's were also 988 codes.  best bet is to look at the code.  The other thing is is that with nitrous you probably want a 4 bolt main which are sort of rare (  I think only the RA engines were, but I am no expert :-?0  on the 400's so you may want to have your block drilled and tapped and get a set of caps
I read were the w72 engine codes a 988XX.
Is it fast? It has a bird on the hood don't it!

72blackbird

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #109 on: September 08, 2009, 08:32:02 AM »
Pontiac switched to the lightweight 400 block design in 75- I know because I have a 75 481988 400 block, and have seen the 75 500557 block as well. Avoid the latter because it has thinner main webs and will crack if you stoke it or build it over 400 hp.

4 bolt mains are nice, but it's generally accepted that the factory 2-bolt setup will support 600 hp. You could run ARP main studs for insurance and it would be more than enough.

Geno
1977 SE T/A (sold :( )
1974 455 T/A (sold :( )
1972 Esprit restomod
1976 T/A restomod
1975 Formula 400 4-speed donor car
1978 Martinique blue W72 4-speed T/A, hurst tops

J-Force

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #110 on: December 07, 2009, 11:35:46 AM »
Hi, thought I'd post two quick questions in this thread since I'm rebuilding a 73 455 trans AM.

1) I have steel headgaskets that require copper coat on the steel side (block side).  Any suggested alternatives since copper coat is not readily available in my part of the world?  what would happen if i didn't coat the gaskets?

2) does anyone know where you can get 4spd shift linkage parts....specifically those rubber grommets, clips, and other linkage assembly fasteners?

Thanks for your help

72blackbird

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #111 on: December 10, 2009, 01:13:14 AM »
Why are you using steel head gaskets? I would use the gaskets that each manufacturer recommends for their aluminum heads, but if you're using iron heads get some Fel-pro's (permatorque blue) and be done with it.
1977 SE T/A (sold :( )
1974 455 T/A (sold :( )
1972 Esprit restomod
1976 T/A restomod
1975 Formula 400 4-speed donor car
1978 Martinique blue W72 4-speed T/A, hurst tops

koury73

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #112 on: February 18, 2010, 06:47:03 PM »
does anyone know where you can get motor mount brackets for a 70-74 trans am??   I need the ones that bolt to the subframe
good. . bad. . . I'm the guy with the gun.


check out my build
http://transamcountry.com/community/index.php?topic=34156.0

72blackbird

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #113 on: February 26, 2010, 05:31:06 PM »
Try Rock Auto- I've heard they still stock that bracket.
1977 SE T/A (sold :( )
1974 455 T/A (sold :( )
1972 Esprit restomod
1976 T/A restomod
1975 Formula 400 4-speed donor car
1978 Martinique blue W72 4-speed T/A, hurst tops

KD9RG

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #114 on: March 30, 2010, 09:55:23 AM »
Building up a 1968 400 that I am going to be putting into my 1977 TA S/E. The original engine was destroyed. My question is on what cam to put into this engine. I am running stock pistons and stock heads. I am doing a full restoration on a TA SE Bandit. I am not making this a daily driver, but I do want it to take off when I stand on it and still be able to use pump gas. I am hoping to get close to 375-400 ponies out of it. I am looking at the Summit SUM-2802 cam. Suggestions?? Mike/KD9RG
1977 TA S/E

Mr. P-Body

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #115 on: April 01, 2010, 07:14:35 AM »
Mike,

   WHICH '68 400? Head casting number?

   400s of the era are "high" compression compared to the later ones. Changes must be made to make the 10.5:1 engine "pump gas friendly". The practical limit for iron heads is around the 9.5:1 range.

   Tell us as much as you can about the engine. Also know that there's a bracket mounting hole "missing" on the '70-older heads that's needed for the alternator/power steering bracket. There's a simple "fix", but be aware.

   Summit cams are "generi-grinds", meant for ease of ordering. They are not "optimum".  Once we know more about your engine, we can make a solid recommendation for a cam that will meet your performance requirements.

Jim

KD9RG

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #116 on: April 23, 2010, 01:05:31 PM »
 Looks like it is 16 which links it to the 68/69 400 HO heads they were made in Feb 68.
 
Block is marked YT with a casting number of 596085. I believe they are the stock pistons, but I am not positive. The Pontiac guru I got them from said they were stock.

  Looking at a Lunati cam PN 307A2LUN. Gentleman that I spoke to there recommended that I use a thicker head gasket to help reduce the compression.

Sorry for taking so long to reply. There is an impeding high school graduation in my house and the "honey do" list has gotten out of hand, so the car has been ignored. Told her I was working on the engine this weekend so chill out. Ha....of course I'll pay for that later. Mike/KD9RG
1977 TA S/E

KD9RG

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #117 on: April 25, 2010, 08:57:59 AM »
I ffigured  you guys would be full of opinions on this one. No comments? Btw, I was wrong about the block casting number it is 9790077 or the last digit could be a 1. Mike/KD9RG
1977 TA S/E

Rick

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #118 on: April 25, 2010, 04:41:02 PM »
From the sound of things, it looks like your static compression ratio is about what it was from the factory for that engine, which is too high for use with today's pump gas.  I'm not sure you can play enough games with the head gasket to reliably drop the CR to the 9.5:1 range you need for pump gas.  The sure-fire way to get there is to have reliefs milled into the pistons to ensure you increase the end volume enough for the drop in CR you need.

Another important bit of informaton re: cam selection is what your rear gears are going to be, as you want the cam to match up with those on a street car.  Ideally you want the torque peak at or slightly below your highway cruise RPM.  An engine for strip use is another matter altogether, as you'll be revving it much higher in order to make as much HP as possible.

KD9RG

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Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #119 on: April 25, 2010, 04:43:20 PM »
Running 3.55 in the rearend. I was a little concerned about the compression ratio. The folks at Lunati did ask me all the questions that I would expect, to be able to answer my question as to what cam they would recommend. I'm am really struggling with what to do. The opinions are all over the place. Mike/KD9RG
« Last Edit: April 25, 2010, 05:15:20 PM by KD9RG »
1977 TA S/E

Re: Pontiac 400-455 Questions and answers. Subthread
« Reply #119 on: April 25, 2010, 04:43:20 PM »
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