Just thought I would share a picture of my '74 Trans Am in case anyone would
like to see it. I know black wasn't available in 1974, it was originaly
Cameo White, but it had a nice thorough black paint job on it when I got it
in 1980. I repainted it in '83. It is mechanically all original with a 455
and TH400, 3.08 rear end. The interior is all original, white seats, the
rest is black. This picture was taken about 4 months ago. I now have 69k
miles on it.
That's a sweet looking 74, the black paint was a good choice. I always liked
the white interior with a black dashpad and carpet. Is the 455 stock? I have
a 76 455 4 speed T/A but it's changed a bit over the years. 455 birds are
getting rare these days so it's nice to see one in such good shape.
Thanks Dave, I appreciate the comments. Yes, the 455 is stock. The only
mods I have are Hooker Comp headers and a flowmaster exhaust system. The
engine has never been opened up. Even the carpet is original. Just a
slight wear hole where my left foot rests against the well. Would you
believe I traded a '74 Pinto station wagon straight across for this car in
1980? I was in the Air Force at Clark Air Base in the Philippines at the
time. This car has been to Japan, The Philippines and back again, none the
worse for the traveling.
Yeah, that is me! I changed my name for another group, but didn't change it
back for this one. I'm not trying to be sneaky or anything.
I've had a chat or two in the past with you. I don't post very often, but
read the group daily.
HoDad? I was going through the computer a few weeks ago and found a file
called HoDad, some stuff I sent you a long time ago. I didn't open the file
and I can't remember what it was for. Damn my memory is about shot but good
to hear from you again.
I pulled the 75 455 out of the T/A and have a 463 in progress. It should be
interesting when it all goes back together.
Wow! A 463! Is that just bored out or are you doing anything else special
to it? I would be interested in the details. I am considering pulling my
engine out next summer to detail the engine compartment, and maybe replace
engine bearings and check the heads out while I'm at it. Some fresh paint
and new hoses, etc. It's not something I'm looking forward to doing, but
would give me continued peace of mind about my engine, and clean up a long
neglected engine bay.
Typically when an engine is "rebuilt" the cylinders are bored out.030
thousands making a 455 into a 462. Technically my '71 is a 462 H.O. now.
And maybe get rid of that 5 quart oil pan? :-)
I'd put in a RA/HO "068" camshaft while you're at it. Its still a factory
cam so it won't cause low vacuum or driveablity problems but it definately
will boost the engine nicely. Installing a factory 3/4-length windage tray
wouldn't be a bad idea either. Those two items should be good for close to
40HP and nobody would ever no the difference.
Ahh, so you do remember me Dennis! Yeah, and that is part of the reason I
want to inspect the motor. When I overfilled the crankcase, I had that loud
knocking that went away when I slowed to 60. Most likely a deflated lifter.
It's been two years and about 750 miles, and I haven't noticed any problems.
But I still have that nagging feeling that something must have been hurt a
little. It couldn't have been good for it. So new bearings, and the cam
you suggest sounds good. Dave suggested older heads, and if the '69 RA3
heads I have access to will work, that should be a good combo. Also the
correct 6 qt pan!
The RA III heads on your 455 is going to give you about 12:1 compression
..which I don't think you are going to like running 110 octane racing fuel at
$3.99 a gallon. I don't think dishing the pistons would be a great idea
either because that might mess up the flame pattern in the combustion chamber.
If you want to bump up the compression with heads look for a set of 1970 455
HO heads. These are D-port cast iron heads that will give you about 10.5:1
compression. You'll be able to get by with premium fuel and octane boost or 5
gallons of racing fuel per tank full.
I don't know how much HP you want but with the RA/HO cam, windage tray, your
headers and exhaust you are probably right around 325 net HP and can still
use the recommended 87 octane fuel.
When I rattled off that list of "older" heads, I think I confused you a bit
about Pontiac heads. I was referring to heads with chamber volumes that
would keep your car running on pump gas but let you bump the cam up a bit.
You have to keep in mind that Pontiac made heads in various chamber volumes.
The 69 heads you are thinking of using (72 ccs) would crank the compression
up into the 11s like Dennis posted which would probably not be what you are
looking for. There are larger chamber heads off of 400s that will bump your
compression up without having to run fuel to prevent detonation. You could
run a 068 cam in your 455 but IIRC you have 8:1 compression and I don't know
how well the cam would work with a compression ratio that low.
Here's a link to a Jim Hand article on Pontiac cam testing in a 455. If you
haven't heard of Jim Hand, he's done tons of testing over the years with
factory parts to see what combinations built the most power. I followed his
advice when I was running the "junkyard 455" in my 4025lb T/A that ran 13.7s
with a crappy exhaust system.
Here's another good site if you want to play with chamber volumes to achieve
a specific compression ratio with flat top pistons:
If your buddy wants to give you those 69 heads, snap them up. You may want
to use them on a 400 in the future or build a high compression engine one
For some real world information, here's a link to a 8.7:1 455 with an 068
cam (you have to scroll down near the bottom of the left hand column to Lady
Dude's 79 T/A Street Car):
Not bad for a sleeved 455 built out of leftovers. ;^)
Thanks for the links, Dave. I already had the Wallace Racing site, but I
saved the others. I'll keep my eyes open for an earlier set of 455 heads.
I have a lot of time before I could use them, so maybe I'll get lucky.
Thanks for taking the time to come up with all this info. I'll keep
everyone posted when and if I get this project started next summer.
Poncho, the 068 cam was installed by the factory in 71-72 455 HO engines which
have 8.4:1 compression. This engine was designed to run on regular 91 RON(87
The 068 may have originally been intended for high compression engines but it
still works great in low compression engines. The RA IV cam on the other hand
doesn't work good at all with low compression.
If you can find some heads in the 95cc range, swap out your 455 4Xs and you
will be amazed at the power increase. 96s, 7K3s, or 6X-8s or maybe a set of
400 4X heads (-3a or -7s IIRC) would work but check the chamber volumes to
be sure. Shoot for low 9s compression and you will still be able to run pump
gas. If you want to spend a bit more money, bump the cam up to a 230-340
duration range, add a set of Hedman 28150 headers (I'm pretty sure that's
the part number) and a 2 1/2 inch exhaust. That combo on a 455 is usually
good for mid to low 13s in a heavy car. The 3.08 ratio won't help too much
but the 455 will have enough torque to yank it off the line with 1.9 to 2.0
60 fts. Shift at 5200 and have some fun. ;^)
A 463 is a .034 over 455 with a standard crank. I want to push this one
pretty hard so the poncho short block needs to be stronger than stock. After
the block is bored it will be filled and a lifter bore brace installed. The
mains will be studded so hopefully the block won't flex. I've had a hard
time getting rods so I decided to cut the rod journals to 2.20 so I can run
BBC Eagle H beam rods. The pistons are custom SRPs with the pin location
adjusted for the rod length and they should be in next week. Once I get all
of the rotating parts the shop will deck the block an balance the rotating
assembly. I'm running a custom solid roller so oil retrictors will be
installed in the lifter bore oil ports. My Edelbrock heads are being ported
and milled for 11:1 compression to complement the cam. I need to install an
electric fuel pump and replace the brake lines while the engine is out. I'll
probably pull the power brake booster and go with Wilwood racing pads and a
manual cylinder. With all of this I'm going to need a roll cage. The 455
should hold up to shifting at 6500 (the cam is good to 7500) so the 100 shot
nitrous jets come out and get replaced with 250 hp jets. I haven't decided
on an axle assembly yet but I'm leaning towards a Dana 60. The 4 speed gets
replaced with a TKO 650 5 speed. The A/C is still intact so it should be a
comfortable cruiser that runs mid to low 11s on the engine.
Today I had to buy a new tow vehicle resulting in a loss of T/A funds so if
it gets finished in 4 months I'll be doing good. I want to take the car to
Pontiacs in the Park in May so I really need to get back to work on the car.
That sounds like a pretty impressive engine you are putting together, Dave.
I guess we can expect to see you in the Pontiac magazines this Spring. I
think I have access to some '69 RA3 heads. Would these work on my '74?
Don't know the casting numbers for sure, but will try to check on them in
the next week or two. A friend of mine has a '69 TA that had a couple of
stripped exhaust bolt holes in the drivers side head, so he bought a couple
of correct replacement heads off ebay for his car. Said the ones he took
off are mine if I want them. I've already got headers and the FlowMaster 2
1/2" dual exhaust system with crossover on the car. Since I'll have the
engine opened up, a new cam is only logical. I'm on a kind of strict
budget, so I can't get too carried away. ;)
Thanks. Yes, over 21 years old. I stripped it to bare metal, then primered
and eight coats of black laquer, and 8 coats of clear. Wet sanded with 800,
then 1500, then polished out. I put less than 500 miles a year on it, (hard
miles ;), the 455 NEEDS to be driven ), and it is always covered in the
garage. My wife did put a ding in the drivers door with her car door. I
still won't let her forget about it!
Ouch! At least you saved it from more careless destruction! Kind of seems
like any damage to our babies hurts more than if it was done to our own
bodies, doesn't it?
I'm changing my screen name back to HoDad, since my friends in here
recognize that name, even though I don't often post. Hope everyone has a
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