[toomanybirds]

Originally Posted by 2manyT/A'S

Well Mark,your post this morning inspired me to go digging in the "uncharted areas" of my basement & thought these might interest the HO guys.
According to the sheet they will ALSO work in the "other" round port 455 (2nd fastest) as well as any other 71-76 455.

As I understand it,a high compression round port 455 was planned as the ULTIMATE large displacement Pontiac motor for 1970 & I'm guessing GM comissioned TRW to design these pistons (perhaps as an OEM application),but with the premature DEATH of high compression engines for 71,there was NO OEM market for them.

One of our contributers here (from the Great White North) has a set of these in a 72 HO with the domes cut down to reduce chamber volume.

These pistons are TRW L2394F. Not too rare or unusual. They may even still be available from Sealed Power, I haven't checked in a few years. I have 2 sets in my parts stash. They have grooves machined for floating wrist pins, and lock rings are included with a set.

They were designed to be used with 455HO and SD455 heads to give about 10.5:1 with a standard bore size. It was common to smooth the "bumps" from the domes to improve combustion efficiency. I believe HO Specialties marketed these pistons and recommended removing the "bumps."

I doubt these were a GM design, as all of the Pontiac high compression engines used smaller cylinder head chambers, not domed pistons.

[OVERULD]

Originally Posted by 2manyT/A'S

I've heard that engine is now in an OTG.

S'A\Tynam2:

uoY thgim tnaw ot evah flesruoy dekcehc rof aixelsyd.


JB

[goathead455]

Originally Posted by 2manyT/A'S

One of our contributers here (from the Great White North) has a set of these in a 72 HO with the domes cut down to reduce chamber volume.

10 years ago that car acheived almost "legendary status" at the dragstrips in the area.

Totally STOCK looking, especially under the hood,it made Pontiac BELIEVERS out of countless Ford,Chev & Dodge guys with TONS of aftermarket speed parts on THEIR cars.

This round port T/A was driven to track on street tires with the sticky tires in the back seat & once installed would run LOW 12 second ET's all day long.

I've heard that engine is now in an OTG. (perhaps we will get an UPDATE?)

It is true that this engine is now in my GTO.
The TRW pistons are still in place but got treated to some Eagle rods this past spring along with new rings and bearings.
As soon as the engine was together the car ws driven to Oregon for the Tiger Run GTO show,getting close to 16 mpg on the 2000 mile round trip.
Last month I finally made it to the drag strip and the car ran 12.43@110 in poor air conditions(4500')
Next year when I can tune the car a bit I hope to get into the 11's but I'll have to wait and see as the track is closed for the season now.
There is the update you asked for.
The Trans Am with the HO was a very fun car and caught alot of people off guard.
In the early to mid 90's there weren't nearly as many 12 second street cars as there is now,especially ones with Q-jets and exhaust manifolds.
The car ran a best of 12.06 but that was in great conditions at a sea level track,it would run 12 teens in the heat of summer.
Here are a couple of pics of the T/A.
I will post some of the GTO later.

[Father&Son73T/A]

Originally Posted by 2manyT/A'S

Well Mark,your post this morning inspired me to go digging in the "uncharted areas" of my basement & thought these might interest the HO guys.
According to the sheet they will ALSO work in the "other" round port 455 (2nd fastest) as well as any other 71-76 455.

As I understand it,a high compression round port 455 was planned as the ULTIMATE large displacement Pontiac motor for 1970 & I'm guessing GM comissioned TRW to design these pistons (perhaps as an OEM application),but with the premature DEATH of high compression engines for 71,there was NO OEM market for them.

One of our contributers here (from the Great White North) has a set of these in a 72 HO with the domes cut down to reduce chamber volume.

10 years ago that car acheived almost "legendary status" at the dragstrips in the area.

Totally STOCK looking, especially under the hood,it made Pontiac BELIEVERS out of countless Ford,Chev & Dodge guys with TONS of aftermarket speed parts on THEIR cars.

This round port T/A was driven to track on street tires with the sticky tires in the back seat & once installed would run LOW 12 second ET's all day long.

I've heard that engine is now in an OTG. (perhaps we will get an UPDATE?)

So,these could be used on 73-74 L-75's?

[Lloyd-TX]

Used those pistons - with the "bumps" milled off and domes polished - in my '75 T/A w/ a 455SD engine MANY years back. I knew a LOT less back then than I do now, but it ran OK. Upper 11's @ 112 with a TH400 and 4.10's.

[OVERULD]

Nice! The smoke from the burn out matches the color of the car very nicely.

BJ

[2manyT/A'S]

You DON'T want to go there!

72CC heads (round OR D port) on a 455 makes TONS of power with INCURABLE DETONATION.

It's not a suitable combination for street driving/pump gas.

[Wareagle]

Heres the 455HO T/A ( RAM AIR IV Heads ) 1.07 mark-partway through this video - he's been driving it for years to shows and races . SDRoger ( 73 SD455 T/A 4 spd ) who I met in Switzerland told me about this unique T/A -- COOL.
http://www.youtube.com/watch?v=D08qJ0XP3kQ

[Wareagle]

I just got a email from SDRoger-- he says his friends 71 455HO T/A ( RAM AIR IV Heads ) runs fine -no problem getting 98 oct.pump gas and shell has 100 oct. pump gas were he lives .

[2manyT/A'S]

http://cgi.ebay.com/ebaymotors/ws/eB...3AIT&viewitem=

Wonder what they will net?

[goathead455]

Flatlander Racing still shows these as available.
Their price is $63 per piston.

[threefidee]

Hint... many people prunounce his last name "Weymooth".....LOL

Jody

[OVERULD]

Hmmmmmm.....I wonder if we'll see this car featured in a future "Shoot-Out" article in HPP???

BJ

[giles]

I could have started a new thread on this but since it is my 455th post I figured that it ought to go here!

What is the general consensus on the most heat resistant engine paint? I had a nice mix made to match the '71 color and of course it burned off the exhaust ports in less than 100 miles!

[giles]

Beuhler....anyone....?

[Transamric]

Chris,...my method for keeping the exhaust port paint relatively healthy, is impossible to do on a together-in-a-car deal, but FWIW, here it is. After cleaning the bare heads, I glassbead the ports till they're spotless. Then a quick rinse off with laquer thinner. Then I dry spray, fog coats of VHT High Heat White header paint. Very dry,...very light coats. Usually 5 or 6, with about 1/2 hour in between each coat. Let them sit over night, at 70 degrees plus, & then shoot my favorite brand of engine paint. I have several cans of old obsolete TRW Service Line paint for the '69-70 Metallic Blue, & I use the expensive OEM paint for '71 & '72. My '69 350HO is the longest time use I've had using this process, & it still looks good, just a bit darkened.

[2manyT/A'S]

Originally Posted by Transamric

Chris,...my method for keeping the exhaust port paint relatively healthy, is impossible to do on a together-in-a-car deal, but FWIW, here it is. After cleaning the bare heads, I glassbead the ports till they're spotless. Then a quick rinse off with laquer thinner. Then I dry spray, fog coats of VHT High Heat White header paint. Very dry,...very light coats. Usually 5 or 6, with about 1/2 hour in between each coat. Let them sit over night, at 70 degrees plus, & then shoot my favorite brand of engine paint. I have several cans of old obsolete TRW Service Line paint for the '69-70 Metallic Blue, & I use the expensive OEM paint for '71 & '72. My '69 350HO is the longest time use I've had using this process, & it still looks good, just a bit darkened.

Any idea how many hours/miles are on the 350 HO since your paint treatment?

[giles]

Back to the subject of 455HOs....

Originally Posted by Transamric

Chris,...my method for keeping the exhaust port paint relatively healthy, is impossible to do on a together-in-a-car deal, but FWIW, here it is. After cleaning the bare heads, I glassbead the ports till they're spotless. Then a quick rinse off with laquer thinner. Then I dry spray, fog coats of VHT High Heat White header paint. Very dry,...very light coats. Usually 5 or 6, with about 1/2 hour in between each coat. Let them sit over night, at 70 degrees plus, & then shoot my favorite brand of engine paint. I have several cans of old obsolete TRW Service Line paint for the '69-70 Metallic Blue, & I use the expensive OEM paint for '71 & '72. My '69 350HO is the longest time use I've had using this process, & it still looks good, just a bit darkened.

I decided to reproduce Ric's process as much as possible with the engine in the car...
Since the non high temp paint recently burned off of the exhaust ports, the heads had no evidence of rust. I cleaned the areas with paint pre-cleaner, and painted the port areas with VHT 1500 degree light grey engine paint (FWIW the masking job was the biggest pain in the whole process) I then shot the areas with OEMs 71 Pontiac blue engine paint (ridiculously expenseive at $42 a can from Classic Industries) and it is a pretty good match. I have about 50-60 miles on it when this picture was taken and no evidence of any further burning.

[ramair kooter]

this is my first post here in response to ricksgto asking about the green ho from texas. i did buy it from an add on here. flew from grand rapids to austin and drove the car back. vinyl top was removed to expose red primer and headliner was falling down on me. pass power window was inop and it was 90 + for most of the drive back. a/c inop too. i bent a lot of minds on the highway though going 80 mph most of the way back with 3.08 cogs. looked like somthing joe dirt would drive! car is an original laurentian green with black vinyl top no wing 455 ho ram air auto. with 30 options. i'll post phs later. here's a couple pics for now. i am tearing it down for a complete resto with pure stocks in mind. i live 20 min. from stanten!

[giles]

Kooter, A big welcome! By the looks of your driveway you already have a serious case of the early second gen sickness! I am jealous...I have always wanted an HO Formula.....