2.89 in a 6 speed
To day I met up with one of our members ,Padgett I delivered to him a 2.89 differential . he has a 6 speed which means he does not need a tcu to control his gearing, as soon as he gets it installed he will let every one know, good or bad. we thank Padgett for being the first to reduce the gearing, example! most of you with a 6 speed know how ,when you take off from a red light , just about the time you get in the middle of the intersection, you have to shift to second. you can't run the gear out,(car in front of you) so is first gear any good at all, Well Padgett will answer that question for us.
Now what about cruising on the highway ? with about 13% increase in speed and about 8% less rpm,Oh and about 4% increase in gas mileage . you notice I said about because Padgett will let us know the real numbers.,,he did say it may be a while before installing the diff into his car.. he has to finish what he has planned for January.
when he does install the diff with 2.89 gear, going from a 3.27 to a 2.89, we are going to sit up and take notice
we await the results, thank you Padgett---- jim
Now what about cruising on the highway ? with about 13% increase in speed and about 8% less rpm,Oh and about 4% increase in gas mileage . you notice I said about because Padgett will let us know the real numbers.,,he did say it may be a while before installing the diff into his car.. he has to finish what he has planned for January.
when he does install the diff with 2.89 gear, going from a 3.27 to a 2.89, we are going to sit up and take notice
we await the results, thank you Padgett---- jim
Last edited by amx1397; Jan 3, 2016 at 12:02 AM.
I am in Melbourne beach drove over to off lease on 528 to look at a truck with/for son-in-law , and Padgett met me there. I go back to Ft Laud tomorrow. sorry i didn't call , granddaughter's birthday, New years,and wife, gave me about 2 hours for me to be me LOL. Merry Christmas and Happy new year to you ,kim and all the family. jim
Well one of my Reattae has a leaking freeze plug so is in the queue for the lift in front of the Crossie. Also planning to investigate a different exhaust system since it must come out to change the diff.
Have hopes it is enough (my initial planning was for a 2.67) but should help some. The difference in 1st at 4k is 3 mph (24 vs 21 mph) & at 70 in 6th, 2200 vs 2500.
In the exhaust since it is a single pipe at the collecor I see no reason to split back out to duals except to add weight, true duals might help for a high revving engine with a lot of cam overlap but that is not what we have here. In fact the 6000 rpm redline is 400 rpm less than my Jeep (DOHC 3.6 V6 290 hp @ 6400 rpm on 87 PON) but then the technology is from the last millenia. Not bad just not SOA.
So what we have is a relatively low revving engine that produces a lot of torque & should be built accordingly. To me that says a single exhaust to maximise scavenging.
Been searching a bit but have not found the cam specifications for inlet and exhaust valve opening/closing. Does anyone have those ?
Found this but nothing on the valve timing & would expect a 10:1 compression to produce 140-150 psi and not 100.
ps was great to meet Jim and he gave me some tips on changing the diff.
Have hopes it is enough (my initial planning was for a 2.67) but should help some. The difference in 1st at 4k is 3 mph (24 vs 21 mph) & at 70 in 6th, 2200 vs 2500.
In the exhaust since it is a single pipe at the collecor I see no reason to split back out to duals except to add weight, true duals might help for a high revving engine with a lot of cam overlap but that is not what we have here. In fact the 6000 rpm redline is 400 rpm less than my Jeep (DOHC 3.6 V6 290 hp @ 6400 rpm on 87 PON) but then the technology is from the last millenia. Not bad just not SOA.
So what we have is a relatively low revving engine that produces a lot of torque & should be built accordingly. To me that says a single exhaust to maximise scavenging.
Been searching a bit but have not found the cam specifications for inlet and exhaust valve opening/closing. Does anyone have those ?
Found this but nothing on the valve timing & would expect a 10:1 compression to produce 140-150 psi and not 100.
ps was great to meet Jim and he gave me some tips on changing the diff.
Last edited by Padgett; Jan 3, 2016 at 10:55 AM.
Well one of my Reattae has a leaking freeze plug so is in the queue for the lift in front of the Crossie. Also planning to investigate a different exhaust system since it must come out to change the diff.
ps was great to meet Jim and he gave me some tips on changing the diff.
ps was great to meet Jim and he gave me some tips on changing the diff.
There may be a ratio to the rockers that increase valve lift over cam lift, and I am guessing that the lift at TDC is lifter preload?
Well if both I & E have the same ratio and the commas are really decimal points (european thing) then 10.8/7.25= 1.48, quite a mild ratio.
Also I expect the 258/268 to be ramp to ramp and not the more U.S. .050" lift duration which would be more like 198/208 effective.
I really have no idea what "Valve lift at TDC" is since 1/2mm and 1mm is not a lot (.020" and .040"). Even with the explination. Can someone please interpret in American terns.
ps not sure if this is the Mercedes M112 profile (claims 20 more hp) but sonds like a cam more for toque than revs.
Also I expect the 258/268 to be ramp to ramp and not the more U.S. .050" lift duration which would be more like 198/208 effective.
I really have no idea what "Valve lift at TDC" is since 1/2mm and 1mm is not a lot (.020" and .040"). Even with the explination. Can someone please interpret in American terns.
ps not sure if this is the Mercedes M112 profile (claims 20 more hp) but sonds like a cam more for toque than revs.
Last edited by Padgett; Jan 3, 2016 at 06:12 PM.
Yep, that has to be it, so about .425" valve lift? I originally missed the () for valve lift, and the normal for cam lift, but I knew that rocker ratio had to be in there.
Woohoo
2.89 in our 6 spd should have been stock.
I been thinking about taking out the resonators and installing a borla pro xs 2.25 dual in / out. Then dual back, a single muffler with dual in / out then I wouldn't need a crossover. Which will need a muffler sometime this year, maybe a new ring and pinion also
2.89 in our 6 spd should have been stock.
I been thinking about taking out the resonators and installing a borla pro xs 2.25 dual in / out. Then dual back, a single muffler with dual in / out then I wouldn't need a crossover. Which will need a muffler sometime this year, maybe a new ring and pinion also
don't waste your time or money on exhaust it does nothing except noise,, when mine was a V6 i did them all best was to remove the rear cats and the resonator I also Did straight exhaust,,no cats,,no muffler just drone loud drone the problem is the exhaust manifolds they are only 1 1/8 opening, if you want to do it right the first time get the headers ,and down pipes if you have to have cats needswings has high performance ones. same money spent and it works. jim
P S when u are ready for a 2. 89 let me know.,,, I can send it to Rudy and he can install it for you.
P S when u are ready for a 2. 89 let me know.,,, I can send it to Rudy and he can install it for you.
Need to change sometime this year anyway, the sharp bend right in front of the muffler is thin and starting to leak has a couple pin holes in it now.
Only noticable when I under the car, would last to next year but will do something about it this year, and don't like that sharp bend in front of the muffler oit back.
If the resonators replaced with the long slim borla pro xs then the bend would not be anywhere near what it is now.
upto the resonators is great besides the pipes being oval instead of round.
Spent much time on net and youtube trying to find a close sound clip with no luck.
Only noticable when I under the car, would last to next year but will do something about it this year, and don't like that sharp bend in front of the muffler oit back.
If the resonators replaced with the long slim borla pro xs then the bend would not be anywhere near what it is now.
upto the resonators is great besides the pipes being oval instead of round.
Spent much time on net and youtube trying to find a close sound clip with no luck.
V6 from inside car , and some p[ic. hope this helps. jim
crossfireduelexhaust11002.mp4 Video by amx1397 | Photobucket
crossfireduelexhaust11002.mp4 Video by amx1397 | Photobucket
V6 from inside car , and some p[ic. hope this helps. jim
crossfireduelexhaust11002.mp4 Video by amx1397 | Photobucket
crossfireduelexhaust11002.mp4 Video by amx1397 | Photobucket
Duals, I guessing no resonators and only cats, what muffler or mufflers and placement?
TY
This video has front cats on, and cat back exhaust the 2 3/4 pipe no resonator, no muffler
Sorry got sidetracked by a new resident: DOHC 6, 7000 rpm redline, five speed manual, 4 wheel disk brakes, AC (working), 1st can do 44 mph, 2300 rpm at 70. Had an extra space in the garage.
Needs some restoration but drives very nice.
See here.
Needs some restoration but drives very nice.
See here.
Last edited by Padgett; Feb 25, 2016 at 10:45 PM.
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