I know the auto makers like to stay away from straight cuts because of noise but I'm not sure I can agree with helicals being stronger then straight cuts. Lenco uses straight cut planetarys in there transmissions. I copied this from Lenco's web site, it looks like they use straight cuts but not sure. "CS1 4 speed 3 Magnesium cases Handles up to 3000HP. Ideal for heavier cars where the advantage of a wide gear ratio selection is desired. Commonly used in supercharged or nitrous oxide assisted Pro Mod and Super class types of cars. Air or lever shift" Same with Jerico's etc.... What I have seen with 400's in the past is, Like you said the helical planetary's trust to the back of the case taking out the trust washer but often the case also, along with spitting out planetary washers. Before the cheap 4l80e straight cut's started showing up at the core companies we were machineing the helical carriers and using torrington bearings inplace of the washers and they seemed to hold up pretty good, but given the cheap straight cuts from the 4L80e's it just seemed like the way to go. Larry, by no means am I saying your wrong I just haven't heard that yet. If you don't mind me asking where you heard that I wouldn't mind reading up on it. As far as the aftermarket stuff goes, I think its the same old problem (chineese bearings)ou: As far as back east goes I'm commited to 4 years. I got diagnosed with fibromyalgia a couple months ago so will see how I'm affected by the NS cold months:TU:
I think what Mikes friend is doing is, the compushift can be used with or without the LED, he is most likely using the LED for his speedo it also shows the trans temp, current gear etc
o No: Sorry to hear about the fibromyalgia Chris. Pain sucks. I can't remember what book I read it in, but it is basic gear train science I was taught in the early 80's when I got my journeymans ticket. They should still talk about the different gears in tech school? :Smarty: Lencos are straightcut for just the reason we were discussing-thrust. They aren't straight cut to make them stronger. Helicals are both stronger and quieter, but I like the straightcut sound. If your interested maybe check out: http://en.wikipedia.org/wiki/Helical_gear#Helical_gears Funny you mention Lencos, I was actually going to go with the new Street Lenco. :3gears: All the problems I saw guys having with Jericos, etc, I thought I'd go Lenco. I spoke with Lenco about putting a 4speed together but I decided to go with the 4L80E so my guys could get some firsthand experience at the swap, and because the gear ratios work better this way too. Never thought of looking at the LEDs, but then, I won't have a controller anyways. I guess I'll just put an electric speedo on the rear sensor and try to make it look good in the dash.:TU: Thanks guys, Larry.
larry are you doing this for a test mule or wanting an overdrive for driveability? good to see you still have interst in the car thing maybe we will se you guys at the track more next year.
Hi Adam, I hope we'll see you lots at the track next year. :TU: I never lost interest, I hadn't raced since I bought the new house and made an addition, and then I was just busy with work- finding a new location, and now therapies since my car accident in the Blazer. My neck is still screwed though, so I have been trying to get my daughter to try racing it. I have no problem letting her drive it after watching her race for the last 3 years at the Western Speedway. I'm actually looking forward to her trying it. I'm also looking forward to driving my son to High School in the Buick. He doesn't want me to park where no one can see us drop him off like when we're in our Honda. I'm doing the swap for a couple of reasons. Sure it's a test mule, but last time at Port Albernie, the car topped out just at the finish line with my old carb with 11.02 @118mph, and about 300 or more feet before the track ended and backed off at 7,000rpm with a 11.04 @98mph when I used NOS: http://cid-60dd5e6bc800909d.skydriv...Tech Sheet-600.tif#resId/60DD5E6BC800909D!215. Anyway after that I borrowed your 1000 CFM Holley and it really woke the car up, so I figured it'll need a taller gear or an overdrive. Anyway I couldn't find anything else that would hold the torque other than a gear vendor (which I'd rather not, because it doesn't lock up the convertor) if I put NOS or stage 2 heads and a roller in it. I spoke to Mike about a stage 2 TE :TU: combo for the street, using 94 octane, it might need fine tuning with cam timing, or compression. But I'm hoping the trans will make it easier, and nicer to drive on the highway. The lockup will supposedly hold up in high gear, so it should speed things up quite a bit, like the time I tried a stock convertor and it felt and went quicker from a 20mph roll, with less rpm. See you soon, Larry.
Just wanted to make it clear: Jamie let me know I guess I should have been clearer. I ran 11.02@118 at just over 6200rpm without the NOS. When I used the NOS I hit 7000rpm about 300 feet before the finish line and then I backed off the gas (and the NOS is pedal actuated) AND SLOWED DOWN, that's why I still got a 11.04 at only 98mph, because I slowed down at the 1000 ft mark. The convertor I was running had about 5% slip on the first runs without NOS so I figure 5% slip/raise rpm from 6250@118 to 7000 and that shows 133mph(@1000ft) , OBVIOUSLY too much gear for the NOS, it needs an overdrive or a taller gear. But the gear ratio is perfect for without NOS, so I figured..... 4L80E.:beers2: Thanks guys
i just wanted to add that you will love the feel of the lockup torque converter! I just hooked up the lockup in my daily driver truck and WOW what a difference on the hwy! I have 3.73 gear, 28" tires, 700R4 and TBI 350, and I now cruise at 300 rpm lower and fuel milage is better as well. Mine is set up to lock only in 4th gear using a vacuum switch set at 9" of vacuum to lock up the converter, and an override toggle switch on the dash to turn it off when towing.
Larry, you got me thinking about why so many people are using straight cuts in all the different transmissions so I had to ask the question. Well first off I have to say I was to impressed with the guy at tci that hung up on me when I started to tell him what I read in wikipedia, he told me that is old school way of thinking (Click) After talking with Lenco, Kilgore, Hutch, CK and a couple others I came up with guys will use the helical gears in lower hp builds because of cost (cheaper to have built in the different ratio's) but in the 400's they all say that the flaws with the helicals gear in a planetary form is, trust, frictional loss, torsional stress that is put on the pin etc due to the small contact patch that moves from one end of the gear to the other. Another thing I learned is not only I was told by a few guys that if you do use the helical cut gears you need to perform oiling mods to increase lube to the helical gears(not needed with straight cuts) along with replacing the trust washers with torrington bearings. Chris
off topic, but, any of you guys hear good things about the 6L80e ? anyway yet to get the TCM to play behind oldshcool hotrods ?
I haven't worked on one yet, but they have a lot in common with the 4L80E. They are pretty scarce, even Rossler Trans doesn't do much with them yet. The 6L90E is out now, but I heard they are actually larger in size then the 6L80E. It would be nice if there are controllers that works with it, try HGM maybe they have a compushift that will work. I couldn't find one listed, but you could use a factory one if you can get one with all the sensors to go with it. They keep coming out with newer and better, what a great time to be a car enthusiast. Larry.
Sounds like your onto something there Chris. I was just telling you what the I was taught when I was learning back in the 80's, maybe the engineers were only speaking in general. I only pointed out wikipedia because it's easy to find. Your right about the oiling mods when you run helical gears, but it is interesting that 50% of the straightcut planets I have worked with had worn out the washers and run the planet pinions right into the planet housing (weird actually-isn't it?). I see lots of that with helical gear with high miles, but don't expect that with a low mile hotrod with the right mods. Just curious if anybody else has seen this? Larry.
I say bring the questions to these guys and see what comes of it: http://www.eng-tips.com/viewthread.cfm?qid=204334&page=9 Devon
Larry, I don't get how a straight cut gear that doesn't trust can wipe out the washers, some times it seems almost like the favour of the week with this stuff either way I think it is very cool that your trying one of these 4l80E's in your car:TU: I have been pushing these with the Compushift for along time, It's a great set-up. Of topic a bit, but I will never forget the time we went racing and you got first place man you were sick:Brow:
I spent a day on the computer and phone calling and asking over and over againou: My head hurts still, I talked to the trans guys and they gave me the #s to some of the companies that make the parts. Everyone said the same thing that in gear to gear form (single) the helical is stronger but in a transmission Planetary gear the rules go out the window, glides don't trust like a 400 and so on and so on. I think I will keep my 3 sets of straight cuts and find some 5 pin helical just in-case:TU: either way, I made some real good contacts in the trans business
Yeh, after your wedding, pu king over the sundeck, and having to open the car door just before staging. Those were the days.
