CSI vs CSL

[srennoc]

After spending sunday with the CSI, monday i spent the day with the CSL. The two cars are so different to drive. They basically have the same injected engine/ drivetrain as each other. The CSL's engine just wants to spin up to redline, where the CSI seems much more docile. Are the fuel maps different in the d-jet ecu? The suspension system on the CSI is set-up much tighter than the CSL. Springs & bars make a huge difference! The CSL feels lighter and looser at speed. The CSI is smooth & solid. Both cars have the same bilstein shocks & tire/wheel combo. Seat position in the cars is also different. The CSL has the scheel seats which makes you feel like your in a go-kart. The CSI has recaro seats which i sit higher up in. I felt like i was a good four inches lower in the CSL. The shift lever in the CSL was so much taller due to the seat position. It had such a long throw. It really surprised me just how different the cars are set up. This will be the last week with the CSL in original state. In next couple weeks it will be taken apart to start the resto. Body & paint will start on june 8. The interior goes in next week. Hopefully it will be done for the august events. More to come.

 

[srennoc]

After spending sunday with the CSI, monday i spent the day with the CSL. The two cars are so different to drive. They basically have the same injected engine/ drivetrain as each other. The CSL's engine just wants to spin up to redline, where the CSI seems much more docile. Are the fuel maps different in the d-jet ecu? The suspension system on the CSI is set-up much tighter than the CSL. Springs & bars make a huge difference! The CSL feels lighter and looser at speed. The CSI is smooth & solid. Both cars have the same bilstein shocks & tire/wheel combo. Seat position in the cars is also different. The CSL has the scheel seats which makes you feel like your in a go-kart. The CSI has recaro seats which i sit higher up in. I felt like i was a good four inches lower in the CSL. The shift lever in the CSL was so much taller due to the seat position. It had such a long throw. It really surprised me just how different the cars are set up. This will be the last week with the CSL in original state. In next couple weeks it will be taken apart to start the resto. Body & paint will start on june 8. The interior goes in next week. Hopefully it will be done for the august events. More to come.

 

[tochi]

After spending sunday with the CSI, monday i spent the day with the CSL. The two cars are so different to drive. They basically have the same injected engine/ drivetrain as each other. The CSL's engine just wants to spin up to redline, where the CSI seems much more docile. Are the fuel maps different in the d-jet ecu?

After so many years, even identical, mass produced vehicles can drive differently. Obviously, as you observed, the differences between i and l can be more than just cosmetic. And don't be so sure the drive trains are completely identical.

First, as an analog, I knew a couple who ordered two identical cars from the manufacturer (not BMW). Both agreed that despite the similarities, one car seemed quicker and more temperamental than the other. I remember hearing how they kept asking the dealer to recheck the valve lash on the more lethargic car. I heard that many years later (when one of the cars needed a new clutch) they discovered the quicker car had a much lighter flywheel. Thus, there may have been changes in manufacture or design that only the manufacturer was aware.

You wondered about different ECU programs between the two models. The definitive answer is "it depends." Some Csl's were fitted with the same 3.0 liter engine as the Csi. Other Csl's had a 3.15 liter block. The advertised horsepower difference was 200 vs. 206. Without consulting the shop manual, I do not think the difference in power was a result of the fuel mapping as opposed to the increased displacement. FWIW, there were three ECU-PSU color coded variants. How they differed is unknown to me other than they were supposed to be kept as matched sets.

hth

 

[tochi]

After spending sunday with the CSI, monday i spent the day with the CSL. The two cars are so different to drive. They basically have the same injected engine/ drivetrain as each other. The CSL's engine just wants to spin up to redline, where the CSI seems much more docile. Are the fuel maps different in the d-jet ecu?

After so many years, even identical, mass produced vehicles can drive differently. Obviously, as you observed, the differences between i and l can be more than just cosmetic. And don't be so sure the drive trains are completely identical.

First, as an analog, I knew a couple who ordered two identical cars from the manufacturer (not BMW). Both agreed that despite the similarities, one car seemed quicker and more temperamental than the other. I remember hearing how they kept asking the dealer to recheck the valve lash on the more lethargic car. I heard that many years later (when one of the cars needed a new clutch) they discovered the quicker car had a much lighter flywheel. Thus, there may have been changes in manufacture or design that only the manufacturer was aware.

You wondered about different ECU programs between the two models. The definitive answer is "it depends." Some Csl's were fitted with the same 3.0 liter engine as the Csi. Other Csl's had a 3.15 liter block. The advertised horsepower difference was 200 vs. 206. Without consulting the shop manual, I do not think the difference in power was a result of the fuel mapping as opposed to the increased displacement. FWIW, there were three ECU-PSU color coded variants. How they differed is unknown to me other than they were supposed to be kept as matched sets.

hth

 

[corsachili]

Nice pictures but are you sure your license plate is mounted properly? Did you make sure to fill the tires on the CSL with nitrogen? That was the factory spec as I'm sure you know, and without it, the car's handling and even acceleration will not be optimized. Finally, the lack of the underriders on rear bumper of the CSi may also have an adverse effect vis a vis unsprung weight with regard to the polar moment of inertia as related to volumetric efficiency, proper swirl and laminar flow over the rear end of the vehicle.

I'd get right on those items Connors. These aren't Hondas here man, and you wouldn't treat your Mercedes this way. Tighten up your game a bit friend.

-tj in Los Gatos

 

[corsachili]

Nice pictures but are you sure your license plate is mounted properly? Did you make sure to fill the tires on the CSL with nitrogen? That was the factory spec as I'm sure you know, and without it, the car's handling and even acceleration will not be optimized. Finally, the lack of the underriders on rear bumper of the CSi may also have an adverse effect vis a vis unsprung weight with regard to the polar moment of inertia as related to volumetric efficiency, proper swirl and laminar flow over the rear end of the vehicle.

I'd get right on those items Connors. These aren't Hondas here man, and you wouldn't treat your Mercedes this way. Tighten up your game a bit friend.

-tj in Los Gatos

 

[x_atlas0]

Man, your cars looks very familiar...

 

[x_atlas0]

Man, your cars looks very familiar...

 

[shanon]

interesting...nice pair BTW!

do they have the same rear ends? open or lsd?
how's the condition of the exhaust systems, are they flowing properly?

so, which one are you gonna let your son drag race you in when he's old enough?

Ferris......!?

:wink:

-shanon

 

[shanon]

interesting...nice pair BTW!

do they have the same rear ends? open or lsd?
how's the condition of the exhaust systems, are they flowing properly?

so, which one are you gonna let your son drag race you in when he's old enough?

Ferris......!?

:wink:

-shanon