1/4 mile this, drag strip that. I know. But if it's any consolation, on your way home when you're driving your street machine on the road, the 2 speed will walk away from the other transmission and leave everyone puzzled. lol
Hey Gary, I resurrected one of your old posts in the juice box forum. Pretty interesting comments so far.
Much appreciated, Derek. I hadn't checked that thread in a while, and just now saw all the great responses (both good and bad). The only 'bad' posts were made about how much of a slug it was with a stock 300-2, which comes as no surprise. It would be a slug with any trans lol
No, not 1/4 mile this, drag strip that, it is called... stop light to stop light. 2 speed walk away ha, you will have to wait till 65 mph before shifting into high gear by that time I will already be 2/3 thru second gear, bye. My 1st gear will already be out by a car that you will have to make up. Better be banging that thing out at 6 grand to keep up. dbl lol. If you want to launch that 2 speed out of the hole you had better be putting in a 3200 stall in it. yeee ha.
Or a switch pitch... Call it what you want, dead stop take off is its greatest weakness, of course. After that, it'll surprise you. It doesn't take THAT long to get moving, and a car length can be made up for. Been there, done that. Use one and see for yourself. I'm sure you'll be surprised. Anyways, corporate slavery time. I'll be back later on for more fun.
Yeah, but don't forget I have the same Buick motor under the hood. Think, When I shift into second gear, will our rpm's now match or will I be higher or you. I have a 373 gear and a 28" tall tire with the 2004 trans 3000 stall. I think I am at 35-4 grand after shifting. more like 4. I forgot we did have one but it was probably a power glide but a 2 speed non the less. We had a 71 Nova with 2 speed and lol we used to beat up on some V8 Camaro's back in the day, they had those 307-305 engine and used to kick their butts. That little 250 6 in that Nova would do 65-70 in low gear and would do every bit of 115 mph.
I'll bet those v8 cars were very surprised to see that 250 straight 6 under the hood after you pounded them Lots of fun no doubt!
Another update to the trans thread: http://www.v8buick.com/showthread.p...d-transmission&p=2642078&posted=1#post2642078
When you compare apples to apples, the same car will perform better when more of the engine's power can be put to the wheels. Dead stop take off is the only real disadvantage, and is more than made up for when the car is rolling, providing this main aspect is true: the engine produces good power within a wide RPM range. Narrower powerbands will respond best with more gears. Match rear end ratio and tire size to the engine's RPM in a 1:1 ratio for an optimal trap pass timing, with an engine that has a nice wide powerband, and then make the comparison. Longer 60' times with the car catching up and often surpassing mult-geared transmissions close to the end of the 1/4 is what many observe. Again, this depends on the combination, but is a closer match when all other things are the same and optimized. If more transmission gears meant everything, why hasn't anyone made a huge 20 gear transmission that kept the engine's RPMs within 500 RPM between each shift, but the downside being is that it was so enormous and extensive that it had 100 hp parasitic loss factor...where does one draw the line? It's all sh!ts n giggles until someone giggles n sh!ts. lol EDIT to the text in bold: Low gear on the ST300 is 1.765:1, and 2nd gear on the 2004r is 1.57, which isn't much different than the TH350's 2nd gear, so the ST300 would still be winding up in low gear well into 2nd on a TH350 or 2004r, with the mechanical torque multiplication being superior on the ST300 at this point. All I gotta say is you better have a perfect hole shot with your multi-geared trans to make the most of the only advantage is has over the ST300, because once that's gone, you're getting caught. Here's an interesting link showing gear ratios of transmissions and some parasitic loss figures. http://www.oldengine.org/unfaq/leadfoot/trans.htm Note the 700r4 sucks up a whopping 70 hp! Geeze. Can that be correct???
I'll agree if you are talking about street racing, nobody can full throttle hook up their cars on the street. The game definitely changes on a shoe-stealing, glued down fully prepped track with fast cars. Acceleration is torque lever factored into weight, pressure against the axles. Simple calculator work showing torque multiplication, up to the point of breaking axles, having to add more rim screws, etc. pushes the vehicle far enough ahead that you cannot make it up at the top end of the track. Polite challenge for engineer types would be to find the formulas for acceleration and play with acceleration and g-force with respect to 2 different speeds, and factor in the ground covered (time elapsed). I'm suggesting this due to winter, lol. Being that you can't make up acceleration (same G force) the same at high speeds vs. low speeds, you would have to add major HP (torque) to make up the time spent. You can't mathematically prove this using the same power and torque curves. Dragstrip sim programs allow fast data changes with your metrics of choice, otherwise the Wallace site has a thingy where you can use theirs or type in an actual torque curve and trans/vehicle data. The programs do work well to actual track times, with accurate metrics supplied. A common bracket racing sandbag trick is to deep stage, taking the R/T launch out of the equation (compared to an inconsistent opponent), and run waaaaaay more power needed to hit your dial in (think, 1000hp car in 11:00 or 10.50 brackets, lol). If you watch who runs close to the dial in, then all you have to do is run alongside your opponent until the end, where you just nudge them out by stepping on it all the way. That's the only way you can 'make it up on the top end'. I suppose if 13 and 14 second cars are being discussed with one wheel peel, then I'm wrong. (I didn't overlook the converter either)
Was talking mostly street racing here, but I suppose when there's 10's or 100's of thousands of dollars at stake in more serious applications, every advantage you could milk out of it would be a wise pursuit, even if you had to do it by hook or crook? Limited slip axles are preferred over open axles, even on street machines, so one wheel peel scenarios weren't even considered in the previous comparisons. lol If one has to resort to using extreme examples of drag racing where a multi-geared transmission would be preferred over a 2 speed, then I'd say the 2 speed is in pretty damn good shape for street fun. I've always said for maximizing strip results, a 3 speed would be preferred over a 2 speed. If the parasitic loss is actually static and not a percentage of the engine's output, then 20-30 hp gained when 1000's of HP are being produced might not seem like a big enough deal to sacrifice an extra gear. On a 350-400 hp engine, it's a lot. The faster the cars become, the less time the 2 speed would have to catch up I reckon. So there's that. However, it does show that the distance can in fact be 'made up for' when the 2 speed is catching the 3 speed. The extra power isn't being added in by anything so much as it is not being taken away in the first place, and again would depend. You might need a tid bit more than .25 miles in order for this to happen...maybe .3? An excellent example of how the ST300 would outshine multi-geared transmissions is on back roads or the interstate, or (for legal reasons) circle track racing instead of drag strip racing, where the transmission is at its strongest instead of its weakest. When others have to compare the ST300's weakness to another transmission's strength, it shows just how good the ST300 really is. Maybe I should stop talking about the advantages of the ST300, lest it become more desirable and narrow my odds of being able to buy one? haha Carry on, fellas.
Wasn't intending on splitting hairs or arguing but adding clarity or shaping a paradigm. Not referring to 1000's of HP or where $$$ is on the line. Most bracket cars are in the 250-700 hp range, with a few hiding more. I was picking on the street cars that waste huge time trying to move from a stop because the extra gear doesn't help them when spinning tires. I wasn't contesting theory, the theories presented are quite sound. I'm saying it's provable every day of the week that there's no comparison whatsoever under 90% of the applications we are driving. 20 speeds doesn't make it better, that's silly... even CVT's (?) with constant rpm would be arguable over the 3 or 4 spd. There's another good comparison that's been seen a bunch of times...same engine, similar gears, between the 3spd auto and the 4 spd. The 4 speed walks away in 3rd gear, where it's the more 'in between' ratio. [Edit, obviously the advantages shift back to to the auto due to no shift time loss and a good converter giving a hell of a launch, even surpassing the top end advantage] What I'm saying is that in the power range of most of our bracket cars, the extra 20-30hp up top cannot make up for the elapsed time lost off the line. It would take a much bigger hp advantage than that. Maybe 100? IDK. I offered up the sims and the formulas so that people could plug the data in from their own experiences and be able to see how much extra hp it takes to make it up on the big end of the track. The advantage does disappear when we are talking about street cars that have tire spin through the first gear. More gear accelerates the vehicle harder until either wheel spin or gear ratio's become extreme enough to create parasitic loss. There definitely is kind of a sweet spot between the right amount of gears to hover between peak hp and the shift recovery rpm without time loss, even with overrunning gear shifting. Again really light cars with high hp can't use the extra gear, there's only so much you can stick to the ground, and then the parasitic loss shows up when comparing 2 side by side.
First off, I want to thank you for taking the time to add your input on this subject. It's greatly appreciated and valued. The 20 speed tranny example was intended to be silly. I still will always insist that the extra power retained by using a transmission with less parasitic loss is more important than people give it credit for, especially those who have never actually used one extensively--because for those who have, the story is different. But then, you're talking about pure drag racing, where the transmission is at its weakest. If the 4 speed walks away from the 3 speed when both are in 3rd gear, it would likely be due to the 4 speed transmission having less than a 1:1 ratio vs the 3 speed's 1:1 ratio in 3rd (final drive), and shows where the ST300's low band is at the same advantage when comparing it to 2nd gear in the TH350 and 2004r transmissions. Thank you for clarifying this. Again, drag racing (as opposed to street driving, and not necessarily 'stop light to stop light' racing, but passing and otherwise overcoming another car when both are already moving, which constitutes the vast majority of all street encounters). When you have to compare the ST300's weakness to the other transmission's strength, it shows that that's pretty much the sole advantage of having the extra lower gear, but the parasitic loss is still very much real in all gears, where the mechanical gearing advantage is short lived. While this does give it a head start, it loses that advantage once it's shifted into 2nd, and even more so with subsequent shifts. Realize also that it's not just horsepower that's retained, but torque, which is multiplied both hydraulically and mechanically (in various RPM ranges) which give it the advantage it needs to overcome the disadvantage of having a 1.765 low gear. What was once a disadvantage becomes a boon as the car begins to move, hydraulically first, and then mechanically once the other transmission shifts into 2nd, all the while the reduced parasitic loss is adding up. This also assumes the numbers are static, and not a percentage of the engine's output. While this may make or break the race with slicks and suspension mods, the game changes drastically on the street with normal suspension street machines using street tires (as you pointed out earlier), which reduces the effect of the sole advantage the 3 or 4 speed transmission had (its 1st gear). You don't need twice the power to catch up to a car that had a 1st gear advantage. The parasitic loss of the multi-geared transmission is sufficient when both cars are similar in weight, gearing, and engine power. This isn't 'theory'. I've done these comparisons personally myself using real cars. The effects can be seen and felt. This isn't to say the ST300 is the best transmission above and beyond all, it's just to say that it has its place in the performance world where most believe it to be nothing more than a component to be discarded. A fair review is all I'm asking. In the end, it's preference (at least to me). Some things work better than others depending on the application. :TU:
The guys that have hot cars on the streets have Drag radials not street tires. Mine don't spin I move out of the hole, either way I would beat the 2 speed, might get me on the highway but off the line or 30 mph I will pull away. Have you noticed they put 6 speed automatics in newer cars, 20 speed gesh. The only way you will win a street race is if you are already going 40 mph. then you will still be in low gear turning 4 grand. Off the line you are going to lose with that 2 speed trans every time. Now wouldn't it be just fun to find out who would do better. Be smart put in a 2004r with a lockup then put in a 410 gear and you will not be touched on the street or the highway I don't care what you got this will beat it hands down. Lower 1st gear with a 410 and some drag radials, bye, locked up in 4th gear on the highway, see ya. The 350 Buick engine is not a 455 that has a ton of torque and a boatload of horsepower, you can get the 350 out of the hole with the gearing you just have to learn how to drive, sideways lol.
^^ Good post. Gary, I'm agreeing that from let's say 40 on up the 2 speed and less parasitic loss will show it's advantages, esp. when the engine can spend more time in the strongest rpm range. My 3 to 4 spd comparison was intended to support that as well as show how torque multiplication wins over parasitic loss out of the hole. Maybe because I was too long winded I obfuscated the most simple aspect. You can't make up the advantage from the first 60 ft. The car is covering ground too quickly by the time you are at the 1/8 mile. Think about the increase in mph from 0 to 1/8 mile compared to the gain from there to finish. You need a significant increase in power to be able to catch up to the car that just walked all over you. Every drag racer already knows this and uses intentional strategies to ensure a win from the light to the first 60 ft.
So Derek, Have you decided what size headers you're going to choose? Had some trans comments I deleted them from this header size thread, getting to much off topic. Seems like there is a thread in the juice box section discussing this so.......... Derek
[QUOTEJust got into this topic and have not read all the posts, but I would like to toss out a couple of things. I have been building exhaust headers for professionals for over 15 years. Cup, PS, Stock, SuperStock, Comp, IMSA, SCCA, ARCA etc. I have been busy making venturis in the exhaust systems at the head to header interface. In more than 60-70% of applications, I can make more power and torque using a tube size with an area as much as 10-12% smaller than the given port area. I would say without hesitation that this is because head porters and engine designers have always been developing their engines and heads based on data from enignes that did not have a header or system that was helping them or working effectively. Therefore, without a exhaust header that would help protect the low piston speed power and also reduce system pressure at maximum rpm's; cam duations, intake flow to exhaust flow ratios, maximum lift flow numbers, (when low lift flow is critical on exhaust, which I think is what you folks are discussing in this thread),etc, have all gone astray. I am often able to allow engine builders to revisit previous conclusions about many aspects of thier engines after they have seen what the exhaust system can do for them.][/QUOTE] Consider the source. (not me)
I already know all this stuff. Might be why I posted that I wouldn't recommend the ST300 for drag racing, where it's at its weakest? I've been seeing '40 mph' on up a lot, and from different posters. Why this magic number? My experience has been more along the lines of 20 MPH on up. Ah well, enough of this. Like Derek said, there's a thread in the juice box forum for this. Merry Christmas/Happy Holidays to everyone.
A 3.73 would be awesome with the ST300 on the street. Street radials, whatever. I assumed no spin (or very little) in the first place, on both cars. I already know which one does better, I've been posting on and on about it now lol I have nothing against the other transmissions, just pointing out the pros and cons and stuff many people apparently aren't aware of. Every single time this transmission comes up, the only thing people want to talk about is its weakest aspect and that parasitic loss and other benefits are negligible, so whatever. I'll take 30 free hp if no one else wants it. :grin: And no, I don't give a **** about drag racing. You have to pick your fights anyway, and if you're already rolling down the road beside someone, the ST300 is at its strongest. Again, enough of this. This thread has been side tracked big time lol Apologies to everyone.
I think I'm going to go with the 1 5/8" header. I really appreciate everyone's input, on both subjects! Merry Christmas
