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Discussion Starter #1
Hi all, I have heard that the large journal pontiac motors (455/428) have oiling issues at extended periods at higher rpms. I'm taking the goat on a "mancation" from NH to NY (5-6 hours) and am wondering if I should be worried. The engine is a 428 out of a 69 bonneville (YH code-360hp/472 ftlbs) punched 60 over with 455 pistons, 428 crank and the GTO heads (62) and rebuilt about 400 miles ago. Running Brad Penn 10/40 oil. I run about 3200-3400 rpm at 65-70 mph. Should I be concerned? Is there anything I can do to prepare and prevent any damage?


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Make sure your cooling system is up to snuff. Whats the rear end gear? I'm betting after the trip you might want to go with something a little taller when your ears stop humming and you get the gas card bill. Still running the 2:56 peg leg in mine even though i have a 3:55 12 bolt posi ready for it. Love getting 16-20 MPG and loping down the freeway under 3000 rpm, and when i do let her breathe she will peg the speedo and then some.
 

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Merging I have almost the identical set up as you. I still have the 428 crank and running 64 heads. I've took it out on a few 300 plus mile trips no problems to speak of. That being said I am nervous the whole drive
 

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I have a 462 in my 73 GTO, which is a 30 over 455 & I take mine all over with no problems ever. I run a 3:73 rear gear & usually travel at 70 mph when on the highway. I run a M54F oil pump with the 60 lbs spring so I get all the advantage of the high volume of the 80 lbs pump with the lower pressure of the 60 lbs pump. I've done this on the last 5 engines I've built & have not had any problems with oiling in any of them. If you don't beat any engine to death at any time you can have a long lived engine by just using a little common sense. Use good oil & good parts & your engine will live.
 

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Discussion Starter #5
Thanks all. I'm running a 4 core radiator with a 170 degree thermostat. Since I set this up, never a problem with heat. Someday I'm gonna change the Muncie m20 for the tremec tko to give me that 5th gear. Running about 50lbs of oil pressure at that speed so I think I'll be ok. Appreciate the input. I feel more confident now and won't worry as much.


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You could have a ton of problems unforseen. You could make it, or maybe not. Ah, the frustrations of mechanical breakdowns, the psychological torment of each new "weird" sound you hear, the uneasy feeling in the pit of your stomach just waiting for the "big one". How could THAT be enjoyable. So tell you what. Fly me up to New Hampshire, I will drive your car for you, stopping in Hartford to visit my brother, and then meet you at JFK airport where you can fly me back home to Charlotte. Deal???? HaHaha.

Personally, I would not be comfortable running 3200-3400 RPM's for extended times, but that is me. I think anything above 2800 on the highway is uncomfortable, not saying you cannot do it. Your engine is still new with only 400 miles on it and I don't know if running at steady highway speeds is a good idea this early on the engine. I did the same thing on my 400CI with about the same miles and drove it 800 plus miles to CT ( about 13 hours) keeping it on the highway and down to 60 MPH on average. Burned up oil on the trip and I don't think the rings really got seated doing this. There are all kinds of opinions on how to break in an engine, but I think steady speeds and those higher RPM's might not be the best at this time. Maybe a little back road driving to break it up a bit. From what I have read, decelerating is just as important to ring break in as acceleration, so varying speeds might be better, but I cannot confirm this. My current rebuild will be broken in differently with a lot more acceleration and deceleration blasts to get the rings seated and no steady speed driving for a while.

I suggest a membership with AAA having the 100 mile towing range. I always have this with any older car and it has come in handy a few times. Hopefully you have gauges to monitor oil pressure and water temp. Don't let it get to hot. This time of year up at your end is still cool, so you should have no problem. Have fun and just be sensible.
 

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As usual, I agree with Pontiac Jim. At least get 1000 miles on the clock at various speeds to seat the rings fully and break in the engine before you do a long, extended trip at a steady sustained high rpm. That'll help your chances. And borrow/buy some super tall rear tires if you can. Anything to get the RPM's down to around 3000 at your cruising speed.
 

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Thanks all. I'm running a 4 core radiator with a 170 degree thermostat. Since I set this up, never a problem with heat. Someday I'm gonna change the Muncie m20 for the tremec tko to give me that 5th gear. Running about 50lbs of oil pressure at that speed so I think I'll be ok. Appreciate the input. I feel more confident now and won't worry as much.


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Tremec is the shiz. I love my OD! Cruising RPM with 4:11's is 2500 at 75 mph. My favorite mod I made to my GTO, and I've made a lot of mods.
 

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Discussion Starter #9
Thanks Geetee. I will drive he as much as I can before I go. I'll also hug the right lane and stop a bunch of times. Alky, how is the install for the tremec? Should I attempt it myself, need a new driveshaft, mount?


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Taking some of he more scenic secondary roads on the way there would allow you to give it a good break in at varying speeds with up and downhills and a lot more fun driving than blasting at 70 and 3200 RPM for hrs. Thats what i did on my first long (200 miles) cruise after restoring then did the freeway on most of the return. Was worried like you but she ran flawlessly.
 

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Thanks Geetee. I will drive he as much as I can before I go. I'll also hug the right lane and stop a bunch of times. Alky, how is the install for the tremec? Should I attempt it myself, need a new driveshaft, mount?


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I installed my own.

The TKO required some floor pan mods that weren't too bad to do and are virtually unnoticeable once done. It did require cutting out part of the trans hump and welding in a new piece that Keisler supplied (I used the same carpeting that was already in the car). I also had to move the crossmember back. I originally used my factory crossmember and I'm pretty sure I had to drill some new holes in the frame to mount it but that was no big deal.

I've since fabricated a custom tubular crossmember that bolts solid to some boxed frame extensions I made because I just didn't trust the factory style crossmember (although I never had a problem with it).

Also had to change the clutch disk to a fine spline from the Muncies 10 spline. All the factory clutch linkage was used and I was even able to use the factory shifter. Driveshaft did have to be shortened, not sure how much, but I did that myself also. Of course I have been a Machinist for a long time and had access to all the proper tools. That may be something to have a professional do.

Since I've installed my TKO 600 they have come out with the RS 600 and I believe the latest is the SS700. The RS600 supposedly doesn't require floorpan mods but I can't say for sure because I have no experience with it. I'm not sure about either of those transmitions but I have nothing bad to say about my TKO or the service I got from Keisler.

Hope this helps.
 

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Thank ALKY. That's a huge help! How were you able to sue the factory shifter? I have an m20 now with a hurst shifter and I would live to keep it looking as stock as possible.


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It bolted right up after I drilled out the holes in the TKO shifter. They don't use external linkage if you didn't know.
 
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