8HP70 and 4.0?

[GoldenGorilla]

Iron block, why?

I buried the lead. The MUCH more important thing is that it comes with a tuned PCM setup to run the engine and the transmission properly.

I agree. I'm pretty sure Blueprint offer aluminum blocks, why not package it that way.

 

[mrblaine]

I buried the lead. The MUCH more important thing is that it comes with a tuned PCM setup to run the engine and the transmission properly.

I agree. I'm pretty sure Blueprint offer aluminum blocks, why not package it that way.

Just struck me as odd is all.

 

[Strizzo]

Tire size and gear ratio??

5.13, 33s and just recently, reflashed shift schedules with HPTuners. I forgot I had saved a draft yesterday so i added more context to my previous post.

 

[mrblaine]

5.13, 33s and just recently, reflashed shift schedules with HPTuners. I forgot I had saved a draft yesterday so i added more context to my previous post.

Then you know it has zero issues in OD at speed on the highway and will hold RPM in OD on even moderate uphill grades unless you have the worst running 4.0 out there.

 

[5632]

It's not in my Jeep but I have an 8 speed duel clutch and there is nothing that it compared to. Absolutely outstanding.

 

[Wildman]

The challenger shifter option is available from every TCU vendor I've considered. The shifter is ugly, but I could potentially get over it. TurboLamik and others (including SGA) also offer paddle shifters.

I looked at a lot of different shifters for the 8HP too... I've got a Kilduff shifter. I wasn't sure about how trying to use a paddle shifter would work off-road so I skipped that idea.

Dodge didn't make the cuts and blips functions for their truck customers to go drag racing. And the transmission needs to be tuned no matter what. (google why cuts and blips exist in the 8hp transmission...for daily driving).

I know why cuts & blips exist for it and as I said I'm just relaying what I'd read. Hopefully by next year I'll have mine swapping in and can report if it works or not & what I had to do to make it work.
To allow the truck transmission to have the ability to have the tap shift option you have to have the truck transmission TCM flashed with a Charger/Challenger flash.

Yes, folks reported that the cuts and blips don't work as well with analog inputs instead of CAN bus.

I hadn't read that.

I'll reach out to Russel from Sound German again about this since I have his kit and see if he can offer some input about the cuts & blips.


And another thing to note is there was an issue when shifting from Drive to Reverse or Reverse to Drive in a panic situation when the rig was moving causing it to go into limp mode. But FRP has got a tune now that cures this issue now.

 

[D's Jeep Wrld]

There's a pretty goodly sized group of folks on here that can be recognized simply by their most common mottos without ever seeing their names.

Smart phones suck (ring any bells?)
I drive like an ass
Tons and fodeez

Should I keep going?

Haha
Smart phones suck=boomer ? I don't know.... But yeah keep going!

My glowing header pic from my Lj and the "Do it for Dale&Be like biff" on my profile might tell you something (I like to party) Im safe&good driver when regularly driving though. But....If theres an empty lot or in the middle of nowhere per usual,Shenanigans will occur

Edit- Incase if I change my profile pic
Here's my current pic

Under the intake manifold it has gold reflective tape,it seemed to do its job since it looks shiny on the intake manifold

 

[Wildman]

Here's what Russel from Sound German wrote on Facebook about Torque Management.

A lot of questions about torque management recently. So here it goes. Number one with the 8hp kit there is always a way to implement torque management no matter what you are doing for engine setup. If you are not a CAN supported ecu then there is a wire to send a signal when it is needed. Implement however you need to on your engine. Next question. Do you need it. The answer is that depends on a lot of factors. How much torque are you making is probably the biggest factor. Load as in weight has a huge impact. Engine mass. IE diesel or v8 vs 4 cylinder. This factors into torque and willingness to change speeds. How you use it to some degree. The best answer I can give to this question is if you have everything else dialed in and torque is accurately being fed to the transmission probably up to around 500 ft/lbs is going to last a long time. Can you run more. Sure. But you are going to start to see shift times stretching out. By the time you make it to 700ft/lbs I think you are probably going to be on a maintenance schedule at best. By that I mean if you are drag racing it will be how many passes do you get before it needs a refresh. The thing is that there is no line in the sand here. For reference the factory 1320 Challenger in drag mode does not have active torque management on shifts at WOT. I personally probably have 100 or more passes on a stock 8hp70 in drag mode. I see now indication of the transmission being unhappy about it. I have also towed a 6500lb trailer at grades without it and see no signs the transmission is unhappy about it. But if you have bad torque info feeding to the transmission you can burn one up at 200ft/lbs of torque and torque management is not going to save you. But I am not loosing any sleep in my stock 5.7 Ram without it. After a few hundred 1/4 mile passes if my stock 6.4 were to wear one out I would be 100% ok with that as well.

 

[ColoJeep]

Then you know it has zero issues in OD at speed on the highway and will hold RPM in OD on even moderate uphill grades unless you have the worst running 4.0 out there.

At what elevation ? , I get what you're saying , seems like a r.p.m. range with the converter locked up would be a knowable way to define what's acceptable .

 

[Strizzo]

Then you know it has zero issues in OD at speed on the highway and will hold RPM in OD on even moderate uphill grades unless you have the worst running 4.0 out there.

With 5.13s yes, I think you and I agree 4.10 or 4.27 and 35s it would not. Which is why I said if you didn't want to spin the driveshafts to the moon you'd probably be limited to just using 7th. I think there are a lot of people (myself included) that would appreciate a shorter overdrive gear to have good highway drivability without the propensity for driveline vibrations.

I've got no major problems with my 42RLE, and my gear/tire selection. especially now with the improved shift schedule

 

[mrblaine]

With 5.13s yes, I think you and I agree 4.10 or 4.27 and 35s it would not. Which is why I said if you didn't want to spin the driveshafts to the moon you'd probably be limited to just using 7th. I think there are a lot of people (myself included) that would appreciate a shorter overdrive gear to have good highway drivability without the propensity for driveline vibrations.

I've got no major problems with my 42RLE, and my gear/tire selection. especially now with the improved shift schedule

Your assertion was that it only works in OD on long downhills which is what prompted my query. Did that change somehow?

 

[mrblaine]

At what elevation ? , I get what you're saying , seems like a r.p.m. range with the converter locked up would be a knowable way to define what's acceptable .

We're gonna split that fucking hair?

 

[jjvw]

I will gladly take an 8 speed auto with a .67 OD over my current 4 speed with a .69 OD. My existing 5.38s stay the same and the entire run up to 8th gear is improved. If and when I need to replace the 42rle, that money is better placed into a better performing transmission.

 

[ColoJeep]

We're gonna split that fucking hair?

Sure , a 4.0 that's 190 h.p. at sea level becomes 174.1 h.p. where you live . And it becomes 138.4 h.p. at my place. At the Eisenhower tunnel on I-70 power drops to 126.4 h.p. or minus 33.47% . That hair is freaking huge in Colorado . Your gear ratio needs to be even deeper here .

 

[jjvw]

Sure , a 4.0 that's 190 h.p. at sea level becomes 174.1 h.p. where you live . And it becomes 138.4 h.p. at my place. At the Eisenhower tunnel on I-70 power drops to 126.4 h.p. or minus 33.47% . That hair is freaking huge in Colorado . Your gear ratio needs to be even deeper here .

538 is barely enough to push 35s up to that tunnel at 55mph even with a supercharger. 589 would help, and we know how to do it. But that sizable pile of money is still better allocated to a better performing transmission.

 

[jjvw]

Your assertion was that it only works in OD on long downhills which is what prompted my query. Did that change somehow?

In my experiences outside the mountains, the 42 will easily go into and hold on to OD while cruising on the highway.

 

[ColoJeep]

538 is barely enough to push 35s up to that tunnel at 55mph even with a supercharger. 589 would help, and we know how to do it. But that sizable pile of money is still better allocated to a better performing transmission.

That's my point JJ , you need deeper ratios . Since we have limited axle ratio options , a transmission with more ratios make great sense. It doesn't seem reasonable to have to build your Jeep around a automatic with a O.D. ratio geared for the Bonneville salt flats. If the issues can be worked out , it is much better to build for a 8hp transmission with much deeper 1st. gear , and multiple O.D. ratios . A huge plus would be lower driveshaft speeds , that would limit even more issues .

 

[jjvw]

That's my point JJ , you need deeper ratios . Since we have limited axle ratio options , a transmission with more ratios make great sense. It doesn't seem reasonable to have to build your Jeep around a automatic with a O.D. ratio geared for the Bonneville salt flats. If the issues can be worked out , it is much better to build for a 8hp transmission with much deeper 1st. gear , and multiple O.D. ratios . A huge plus would be lower driveshaft speeds , that would limit even more issues .

If the premise is a replacement for the 42rle, then the axle gearing requirements are identical to the 8hp. If the 8hp is replacing any other TJ transmission, then a regear ought to be part of the project. The 8hp is not a means to avoid proper axle gearing.

 

[ColoJeep]

If the premise is a replacement for the 42rle, then the axle gearing requirements are identical to the 8hp. If the 8hp is replacing any other TJ transmission, then a regear ought to be part of the project. The 8hp is not a means to avoid proper axle gearing.

The debate would be , what is the correct ratio ? and do you have to run the transmission in the highest gear available ? I think that's much of the 42RLE drama, Folks that absolutely have to run in O.D. are forced to run real deep axle ratio's . The 8hp allows a far wider latitude . A 42 RLE in OD with 5.38 gears is the same as a 32 RH in 3 rd gear with common 3.73 axle ratios. I'm not a huge automatic guy , but I could run a 8hp in 5th gear and have a 5.29 final ratio with 4.10 axles. Plus you would still have a mechanical crawl ratio of 52.52 with a 2.72 low range ratio , which is still deeper the a stock Rubicon . Of course all this depends if the 8hp is a reliable transmission , in it for the long haul . Just food for thought .

 

[jjvw]

The debate would be , what is the correct ratio ? and do you have to run the transmission in the highest gear available ? I think that's much of the 42RLE drama, Folks that absolutely have to run in O.D. are forced to run real deep axle ratio's . The 8hp allows a far wider latitude . A 42 RLE in OD with 5.38 gears is the same as a 32 RH in 3 rd gear with common 3.73 axle ratios. I'm not a huge automatic guy , but I could run a 8hp in 5th gear and have a 5.29 final ratio with 4.10 axles. Plus you would still have a mechanical crawl ratio of 52.52 with a 2.72 low range ratio , which is still deeper the a stock Rubicon . Of course all this depends if the 8hp is a reliable transmission , in it for the long haul . Just food for thought .

This isn't a new thing we have to figure out.