› Forums › Forums › CURRENT MEMBERS RIDES / RACING › 55 E/G – New old ride
The 4L80E transmission is in the 55 and it works. Took the 1st test ride today, about 4 miles. With the overdrive and the lockup converter the rpm is only 1600 RPM at 60 MPH. That is a 900 RPM drop compared to the TH400. Hoping to see a big improvement in fuel mileage. Ready for the Salt Flats next. 😆
Especially with the AC on. Tom you never cease to amaze me, keep it up you’re an inspiration.
Pat
Yeah Tom, what Patina said ❗ What a major improvement, AWESOME ❗ 😮 We/re so
glad that you share your projects with us. You’re still in good shape with that vibration issue ❓
Frank… 😎
Thanks for your comments guys, you help make this project fun. The vibration problem was gone with true and balance and than the better improvement was using the radial tires.
I was thinking of the RPM it took to go to the local Cruises just a couple of weeks ago. This is quite the extreme, with the 4.57 gear and the small 29″ tall tires it took 3000 RPM to go 36 MPH. After changing the rear gears from 4.57 to the 2.75 we cruised to Orlando using the smaller tires. Going from the 33″ tall tires to the 29″ tires, it increased the RPM by 500 at 60 MPH (2000 to 2500). And now with the 2.75 gear and the 4L80E it’s 1600 RPM at 60 MPH and that is with the small tires.
Now here’s more fun thinking.
One day we might try the bigger tires and if that reduces the RPM by 500 at 60 = 1100 RPM. I was reading on the internet that Ford made rear gear ratio of 2.32 but I don’t think we could idle the engine low enough. Just how crazy are we old drag racers? 😆 😆 😆
HEY
Just put batteries and electric motor ta run overdrive!
Just like road race cars with an electric motor ta give them that little push at top end!
‘V’
V don’t give him any more idea’s.
Pat
Hey Tom, just found out that my buddy, Carl “Bootie” Booth’s brother John lives in the next
town over from you, Auburndale. So we’re telling him to be on the look out for an orange
55 Chevy going like a bat out of hell testing it’s new overdrive transmission ❗ 😮 😆
“Small world” ❗
Frank… 😎
Frank….If he is into hotrods, The Burger King, Harden Blvd Friday evenings, nice weather like the last couple of weekends we see about 150 cars. The 3rd Saturday Plant City afternoon is another good show. Headed there tomorrow, well since it is Saturday already, later today. Have him look us up.
The 4L80E seems to be a good transmission choice for cruises and racing, working real good. The Plant City show will be the 4th time out with it.
Hey Tom, I’ll pass that car show info on. Thanks ❗ Really glad to hear that the trans. is
working out for you. I usually have to try a lot of different things before I find the right one. 😆
Frank… 😎
Frank….Still learning the transmission. Started out with the standard program for shifting but have made 5 new programs so far. I get to try 2 new programs every time we take the 55 out. It is pretty neat to try a program, come back and make changes after each test ride. Because of the extreme rear end gear (2.75/1) it is easy to set the shift points too early. The lockup also drops the tack back down another 700 and 900 RPM. What that has made us do is move the lockup from 3rd gear up to 4th gear and up to about 60 mph. Funny going down the highway, having the trans shift and than even lockup the converter at just a little above an idle RPM. The engine likes a little more RPM than idle while cruising, even the torque of the 496 is off the curve at idle . After we finish setting up the street programs we will start on the race programs.
The electronic transmission is quite interesting, fun and at times challenging.
Tom, that sounds pretty wild. I don’t have a great understanding of auto. trans.,
so some of that is Greek to me. 😆 It sounds interesting though. You’re able to
customize the performance of the trans. with all these programs. Let me ask you this.
When you set this trans. up for the race mode, are you keeping those highway rear end
gears or are you changing back to your race rear ❓ This is cool ❗ Keep us posted…Good luck. 😀
Frank… 😎
Rear end gears, we have several assembled center sections. For street cruising we use the open 2.75 and when we race we install the 4.57 with the spool.
Transmissions, we wanted an overdrive with the lockup converter for cruising. Actually bought a 700R but it was not strong enough for racing, plus it didn’t have a transbrake. That would have required 2 changes to go racing, the transmission back to the TH400 and the center section back to the 4.57. After a lot of research we found a place in TX that makes the 4L80E that shifts fully automatic and has a transbrake. The 4L80E has the strength of the TH400 but also has the overdrive and the lockup converter for the street. The “E” in the transmission designation is for electronic controls. The transmission is shifted by the factory computer in all the newer vehicles. That factory computer senses throttle position, vehicle MPH or RPM to make the solenoids in the transmission do the automatic shifting.
Since the 55 didn’t come with a computer we looked to aftermarket for a stand alone computer and there are several manufactures. Once you have a computer than you get to figure out how to use it and that’s were we are now, learning.
Tom, that’s freaking AWESOME ❗ 😆 😆 Thanks for taking the time to explain
everything to me. I’m just creeping out of the past. You’re already into the future ❗ 😛
Frank… 😎
I have resisted the laptop computer run cars up till this transmission. Everything has been old school till now but I kind of like the technology. Next big step might be an LS6 aluminum engine. 😆
From what I hear Tom once you go to the LS motor you’ll never go back, then we won’t be satisfied with that, we will have to go with twin turbos. Can you say 1800HP and 20 MPG without laughing!I looked into this and it’s intoxicating.
Pat