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Post by casias on Nov 15, 2012 7:37:40 GMT -5
For those of you still following the project, here are the highlights:
1) Drivetrain is operating well. No issues with clearances, or driveline vibration.
2) Motor retains stock configuration, and tune. So it is completely dependable.
3) Acceleration is smooth, pulls hard, and cruises with rpm that is slightly higher than I would like. I will probably replace the ring and pinion with something in the 3.60-3.70 range to achieve a little bit less cruise rpm and more efficiency.
4) In retrospect, the 6L90 transmission is the weakest link for a DIY swap. Not only is there less tuning available, it required cutting the tunnel,and repair, and is described as having less robust internals than a build 4L80. I think the 4L80, which is widely supported and has less complexity and overall size would be a much better choice for someone looking to make their swap quick and dependable. The 6 speed would also be a great option,w ith the addition of a clutch assembly, but I haven't done any research on that.
5) This swap is feasible. I am going to do a complete write up with steps, planning and such after I reach about 2-3000 miles.
6) I should have kits available for the motor adapters in the next couple of weeks. Holidays are coming up, so that may change the schedule somewhat.
7) I also have a couple of rear disc brake kits available and ready if anyone is interested. Email me for information.
Scott
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Post by casias on Nov 27, 2012 13:02:07 GMT -5
Testing continues.
1) Truck now has about 400 miles without issue.
2) Mileage has improved to 14 mpg. It would probably reach the goal of 16 mpg with rear ring in 3.55-3.70, instead of the 3.92 currently in it. This,when compared to edmunds report of a 2007 silverado 1500, 6.0 L is pretty good already, as they acheived 14.1 during 400 miles of driving.
3) Cabin noise is much less than magnum 5.9 cabin noise, with a set of dual dynomax super-turbo mufflers, high flow cats, and header wrap around the manifold extensions.
4) Shifting has improved markedly as the miles have added up. I really think now the short and long term fuel trims were way off given an initial exhaust leak on both sides ahead of the O2 Senosor. We tried band clamps, with the intention of removing and welding the system once we were sure it was done. Now welded, long-term fuel trim has decreased from 23.1%/15.6% (right bank/left bank) to 6.5%/3.8%. Electronic feedback ECU's with drive-by-wire accelerator are sensitive to everything, and the shifting and throttle response can be affected.
5) It drives very interesting. A little weight off of the noise improves handling, turn in, and body roll, without being bobbly. I think setting the motor down and back, at the expense of cutting the crossmember was a good choice on our part. This truck also received rear disc brakes, which has made stopping very crisp. Probably one of the performance mods I have found most valuable on rear drum brake dakota's and durango's.
6) Oh, and being attacked by the R/T community has been....fun. They love that magnum motor.
Scott
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Post by casias on Dec 1, 2012 6:53:27 GMT -5
As I had previously said that I was unhappy with the 6L transmission, I am going to retract that statement.
Yes, it is a little large and required cutting the trans tunnel. But I fabricated a fiberglass console that has improved cup holders, ending yet another frustration with the shallow cup holders that allow anything tall or narrow to fall over around corners.
The issue with the transmission and the shifting was more closely related to exhaust leaks. Initially, we chose band clamps for the four junctions (manifold to cat, cat to muffler, on each side). They leaked, causing huge adjustments in the short and long term trim levels. V-bands have been welded in, leaks are gone.
Transmission is fantastic!
It has not gone to the tuner yet. The cost of stepping up the cam and retaining VVT is not justified, and the minimal gains on the current set up aren't either. Removing VVT and going to an LS3 style cam, sprocket and cover, then tuning could net an easy 80-100 hp, putting it near 500.
But that is not the goal right now.
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Post by jsmith564 on Dec 1, 2012 19:47:27 GMT -5
Was wondering how it's been. Glad your enjoying it so far.
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Post by casias on Dec 2, 2012 15:17:32 GMT -5
Yes, it is nice. Took it to the Snowbird Nationals in Bradenton last night for its first long cruise. Does very well, with maybe a little vibration at about 110 mph. I might consider adding 1-2 degrees to the rear end, or lowering the rear with a 1-2 inch spacer. I haven't decided yet. At 60-80 mph, however, driveline is excellent.
Next will be A/C and additional heat and sound shielding.
Also, we are in the process of changing the website.
Scott
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Post by bleedorange on Jan 2, 2013 9:22:33 GMT -5
Scott,
Please give me a call @ 813-433-4942 or E-mail at BleedOrange1967@Hotmail.Com
I'm looking for the motor mounts and tranny mounts for 4l80, I have a 2004 Dodge Dakota 2wd Standard Cab waiting for this ls3 I have sitting in my garage. Do you have kit avail yet?
Thanks,
Jeff
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Post by casias on Jan 2, 2013 21:20:28 GMT -5
Hey Jeff.
Thanks for your inquiry. It turns out you have a "Next Generation" Magnum motor, which is 3.7 liters. I am going to start a new thread to discuss swapping your motor with pics I found.
Scott
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Post by jsmith564 on Jan 15, 2013 21:19:32 GMT -5
might be wrong but i'm pretty sure 97-04 all had 3.9 v6
3.7 was used in the next gen dakota
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Post by casias on Jan 16, 2013 7:52:19 GMT -5
It was a mystery why chrysler dropped the 3.7 in the 2004 dakota for the last year of its run, since they had used the 3.9 up to 2003, while beginning to switch to the 4.7 in 2000.
It was more of a mystery why the "next gen magnum" existed at all.
With sorry performance, difficulty rebuilding and limited ability to modify it, yawn.
Let history repeat itself with the Pentastar. A great performer at 300 hp, but with all of the integrated parts, hot rodders won't care.
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