This is me too, I drive the car. Hammer it.

Gears are for shifting. That is the most fun part with a standard. Can you say Grampa. lol. I know I shouldn't post this but that's the way I feel. That driving is so boring.

https://www.youtube.com/watch?v=gtHulbSZOnw

https://www.youtube.com/watch?v=4-YULu5wT18 10.32 at 132 mph

Hammering on the car all the time isn't a normal thing. We do drive these things daily after all. We have to drive civilized most of the time and that video shows that even a big cam in a small engine doesn't need to be downshifted all the time. That's the whole point of the video. If 455's can't do that then the engine either has issues or you guys are telling me a high strung 302 does it better.

I am actually putting a load on it. That's about 1/4 throttle in high gear at very low speed and it picks up speed very well with no need to downshift. You can actually mat it if you want, it just makes 4 barrel sounds and accelerates, but it's honestly just a waste of gas and unnecessary load when your putting around 35 mph zones.
Probably would have shown better what the engine was doing if I put a vacuum gauge up there.

The real point is a 254@ .050 cam in a 302 that has a reputation for being so high strung has no problem with a .64 5th gear and 3.55's out back. If that engine does it then most any other engine shouldn't have an issue

Actually most do drive somewhat civilized on public roads but you are missing the whole point of that video if you think I should be hammering on it.
I have other videos showing that if that's what you want to see. There is a time and a place for that.

How do you treat your daily driver? Hammer on it all the time? Just cause I daily drive a muscle car doesn't mean I should be racing at every stop light. Treat your daily like that every day and it likely won't last very long

That's a sweet running car!

This entire thread is why these kind of decisions are very individual and specific to the owners desires, needs an usage. There is no one-size-fits-all solution. That's what also makes it fun and interesting. Your car is your car. Each if us has to be honest with ourselves about the car we have and how we use it. To pick your setup based on someone else's use that's different than yours, will probably be a mistake.

For me, I always try to keep my car in a gear where I have responsive acceleration if I want or need it, without a shift. That's just me.

And to FJ, I'm not disparaging or criticizing you. You are an awesome dude. You have more car knowledge than I ever will and your contributions on the forum are epic. You've got your stuff setup the way you want it and that's fantastic. We just may disagree on this one a bit. :beerchug:

Nothing wrong with that. That's what makes these threads great. I agree, and have the option of buzzing around in a lower gear if I want to, maybe when I'm feeling a little spunky. Pick which one ya want and have some fun, but I also have the option to just let the engine mosey along, sip fuel, and be just about completely quiet. That's what that video is about.

Honestly a big engine is really good at doing that, should be better than that 302 actually.

Thanks,


And just for giggles, it does zing when ya want to. Here's a short video on a chassis dyno. Interestingly enough, it has a decently flat torque curve that hangs on quite a while and torque peak just about matches the HP peak. Contrary to what is common folklore with these engines.

https://youtu.be/jI2SxDxH8bM

Very nice - must be fun to drive!

The wallace calculator says right now I turn 2730 rpms at 65 mph. With a .81 it would be 2200 rpms and with .68 it would be like 1850 rpms. At 75 mph its 2550 with .81 and 2140 rpms with .68. Either OD would be a nice improvement over what I have now. I guess something to think about.

The Tremec calculator may be useful, it lets you see each gear and switch between multiple transmission options

Ok, First of all, I shouldn't have said Grampa. I was just busting your chops. For that I'm sorry. I have alot of respect for you and very much value your opinion.

I don't drive uncivilized. I obey the speed limits and once in awhile when no one is around me I checkout the gears. Meaning bringing the rpm up to 5000 or 5500.

I understand what your doing in the video and that's great for you. but for me I don't drive my car like that. I don't worry about the cost of fuel, nor do I care. As long as I am able to get gas and still drive is all I care. I built the car to have fun, not my daily driver. I drive a 20022 Denali HD 3500 diesel which in itself it alot of fun to drive. And I treat it like gold. I also don't drive or abuse my car. Never have. but I do open all the barrels on the 950 quick-fuel every time I have it out. Well almost every time. lol Everything in the car from front to back has been beefed up to handle it. Anyway, I'm rambling on here. So that's it...

5th and 6th in the close ratio Magnum T56 I have in my 535ci Formula (3.50 gears, 26.5" tires) are .80 and .63. That 6th gear on the freeway, where average speeds are around 80mph, is just awesome. We were planning on a 2.87-.81 TKX and 3.70 gears in my son's TA, but after spending time in my Formula and considering how much time he would spend on the freeway, we decided on a .68 TKX and 3.25 gears.

Silversport recommended .68 with my combo even though they didn't ask much on driver styles.

Yeah everyone is way overthinking this.

.68 OD is what works for the majority. The .81 is for road race cars. The .72 version has too low a first gear for most Pontiacs.

Just get the TKX trans. Ha.

Yeah, because honestly it doesn't come down to driver style. More importantly it's cruise rpm range based off your setup and intended purpose for the car. What ever drive style you have you adjust by picking a different gear to be in when you want to ;) Then let the overdrive do it's job when you need it, whether that be highway cruising or road racing.

Madgoat is correct, the .81 overdrive was originally designed for road racing to have a close ratio from 4th with little rpm drop for long WOT straights. It was not meant as an overdrive ratio for the street originally.

The .72 which used to be the .68 option with TKO's, was meant for cars that have a tall rear gear like a 3.08 that people didn't want to change, and came with a 3.27 1st gear as a result to help takeoff with more gear multiplication.

When running 3.31/3.55/3.73 that .72 option isn't necessary and in many cases the 3.27 would be on the short side with those rear gears anyway.

You can look at it like this. Ideally you want an overdrive to provide you with a cruise rpm on the highway anywhere from 1800-2200 or 2300. That should range from 65 mph to 75 mph. Something in that realm. Any more rpm than that to reach those speeds and you start to lose the benefits of having an overdrive, which are using less fuel, less noise, less wear and tear, less engine temps, and just all around more comfy cruising. Based off your rear gear and tire size, play around with a calculator and see where you want to end up.

My small rant for the day, Tremec has already removed enough overdrive ratio anyway, that I wasn't a fan of to begin with. Instead of going to .68 they would have been better served to leave the .64 and instead change the 2nd and 3rd ratios for a closer ratio box. Because of those reasons I've actually become more of a fan of the G-force T5's. Rated at the same power levels but the ratios are more preferable. 2.95/1.94/1.34/1:1 and you have a choice of 5th being .60 or .63 and I think there is another one slightly more. What a sweet shifting trans that drives much like a close ratio muncie, and a 5th gear that actually does something, nice small light weight package that fits in anything, and surprisingly it's a few hundred bucks cheaper. 3.73's with this trans is perfect. I keep hoping Tremec will dive back into the gear ratios and offer some better choices.

That's funny because MDL and American Powertrain both recommended that if I got the .68 I should put in a 3.73 rear.

And to say that driving style and usage is not relevant, well, I don't know what to say about that.

With my TKO600 (.68OD), my GTO initially had a 3.55 rear gear. Cruising around my area (country 2 lane roads) I felt like I was either running more rpm in 4th than I liked or bumping around in 5th gear at lower rpm than I liked. I swapped the 3.55 8.2" for a 3.73 8.5" and it seems a better fit. Driving style and usage did make a difference for me.

At 65 mph the 3.73 with .68 does 2090 rpms
At 65 mph the 3.31 with .81 does 2200 rpms
At 65 mph the 3.31 with .68 does 1855 rpms.
At 65 mph the 3.55 with .68 does 1990 rpms.
And it sounds like this is all with a very healthy 455 in your car.

With my setup and a .68 at 55 Im only turning 1570 rpms. I guess i could go try my current setup and cruise at 1500 and see if it likes it with no bucking or anything.

I've got a mild built 455 in the 400-420 hp range with a smaller cam HFT cam, I was going to get an auto gear 4 speed originally so when I did the 8.5" rear swap in my car went with a 3.42 gear, long story but the guy screwed up and it roached the gears, Different shop installed 3.23 as they were available quicker and I was tired of waiting and wasting the summer, well in the fall the TKX was released and I had to have one, I went with the .68 overdrive as the supplier I purchased from had more in stock at the time. The car runs and drives great with this combo no bucking at lower rpm in 5th cruises 65 at 1869 rpm with a 25.8" tire Had I known the TKX was coming out I would have gone 3.73 from the start and I'm considering a gear change now more so for the better acceleration from a stop, my buddy just went from 3.55 to 3.73 with a similar set up and swears by the 3.73

Don't forget it won't be exactly the same as if you had the TKX w/.68. If you do that test with your car it will be with a 3.31 rear. If you did the same RPM with a TKX @ .68 that would be like doing 1570 RPM with a 2.25 rear.