Marlene rides the rollers
 

Today, Marlene the wonder wagon rode the chassis dyno at Austin's Colvin Automotive (www.colvinautomotive.com).

I wanted to do a 'before' for the 'before and after' wattage check as part of the conversion to a manual transmission. It will be interesting to see just how much energy that torque converter was soaking up when I do the 'after' runs (hopefully) later this month.

It was cool! The tech did some extra fussing with the optical tach sensor to make sure that we were able to get the data we needed to calculate torque plus, we actually did four runs to insure that we were getting a clean record.

Output was pretty typical for a 617.952: 125-127 ft/lbs of torque and 78-79 hp. Look at the graphs (http://berryhillfarm.us/benz_stuff/Dyno/dynochart.jpg) and you can see the miniscule increase in output that was achieved by turning the ALDA screw 1/2 turn CCW.

How much are those runs costing you?

Looking at that dyno sheet, and my personal experience, (i was just thinking about today), your not going to see a change made with the ALDA on something like that. It only starts at 40mph, all the difference I ever feel with adjusting the ALDA, and it is a very considerable difference, is on standing takeoff, sub-2000rpm, if not lower.

I'm using mine to tune my shift points at the moment. Second gear seldom holds long enough to suit me at light throttle, such as when the ALDA is turned up and the motor is makeing good power off the line(and requiring less throttle), so I'm backing it off slowly such that I am at a slightly deeper throttle position for *normal* acceleration, as the trans tends to hold 2nd longer at such positions. It's a balance act with the bowden cable and the ALDA, I'm trying not to toss adjusting the vacuum bleed into it at the moment, it's just set to OEM spec. If I can get this to my likeing it would be nicer than the valve body replacement I've read elsewhere that is *suposed* to help with it.

Can't wait to see your manual trans dyno numbers. And is there no RPM readout on that?

It's great to see someone post results to compare with!

For the record, here were my results: http://www.tulsadyno.com/customers/Cars%20and%20Trucks/Mercedes/300%20TD/Lance82-300TD-DynoGraph.jpg

The dynojets are calibrated differently or I must have done some things right since I get 9HP and 27ft/lbs higher power output. :D BUT, the major difference I see is that your HP levels out far faster than mine. By 2500, you are at 78HP while I'm still at 68HP :confused: and your torque drops below 100 by 3000rpm, where mine does so at 4500rpm.

How quickly did your boost top out? (What is your boost, BTW?)

I see you didn't go past 3800 or so (71mph vs. 103mph). Did you not want to rev it any higher?

Interesting, I wonder how they would do side by side..... :D

The posted rate is $54 for the setup and first run then $15/run ater that. Colvin only charged me for two runs even though we have the data from four.

They sent me the datasets via e-mail and a link to the Dynojet site where you download the data reader. You can dork around with it to your heart's content...displaying the info in various configurations (MPH, RPM, etc)

Here's the same data with RPM instead of MPH: http://berryhillfarm.us/benz_stuff/Dyno/dynorevs.jpg

That makes sense and explains why there wasn't a more noticeable difference after the ALDA adjustment (it's been a long time since I piddled with it).

FWIW, they only enable the datalogging after the car is in high gear and, the dyno won't actually log until the computer detects parity between engine rpm and roller rpm (no slipping). If the transmission shifts while logging, the dyno reads the inertial spike as false peak HP.

Some of the difference can certainly be attributed to the weather. It was right at 80F and 50-60% RH...not exactly dense air. In fact, the tech asked me if I was really sure I wanted to run because the weather wasn't very good for it.

But, that said, I've ALWAYS felt like this car wasn't making the same HP as my other 300. Now I want to take Lilly over there and run her too!

I forgot my boost gauge but, last time I checked, it was 9.5 PSI and it was opening the wastegate anywhere above about 2000-2100 rpm.

We ran it to 4500rpm. In regular service, I never rev it past that point so I didn't see any reason to do it here either.




__________________

Did you ever do a post conversion dyno run? Has anyone? I am very interested in seeing how much power that TC and pump accounts for.

No, I never got managed to do that...but, I probably should do that one of these days.

Wow there must be some serious drivetrain loss, those numbers are far beneath published figures for a 617 turbo! These cars have no power!

Crank HP != RWHP?

Major drag in the drivetrain going from 123hp to 78 and 170tq to 125!
Yes I know crank and rear wheel yield different numbers but this is ridiculous!
I'm sellin'

Here are my before and after dyno results. More HP but less torque.

Note that they were on different types of dynos and in different states.

DId you think these were fast cars before you saw the dyno chart?

Get a 280E or 280CE if you want a W123 with decent pickup...will get similar fuel economy too.

I've got mine as close as I can get to "stock" power. This is with unmodified injection pump internal settings. 99.9hp and 148tq without water injection.

you guys know what a joke is?

won't do the 280E, too complicated
besides, my diesel drives just fine, but when I look at those numbers I'm amazed