Hussie the S4...

[bharper]

Tnx Sanj!

[ArtB]

Brian,
Nice purchase. And I think most of us spend so much time on youtube is to watch cars that actually are running when our's are NOT! LOL! A word of note also on the MSD coils. The MSD coils do not build up enough current and fall short of where the original GM coils are. The MSD coils claim more voltage but their amprage is too little and they do not waste spark as well either so idle quality can suffer greatly. I know this from experience. Trust John! He is a true EXPERT on the subject! Additionally, have lot's of vaseline or lubricant ready....... The silicone hose upgrade is Brilliant, however the hoses are EXTREMELY TIGHT! The water pump outlet has a large bead on it and it is a royal PITA to get the hose over the bead and seated to clamp. All of the hoses fit, they are just very snug. Keep us posted on the progress, and nicely chosen set of upgrades. I like the upsized valves and bowl porting option myself, but that's just me. I did that when I built my engine a few years back and the boost response is competely different! The engine is eager to rev and the turbo seems to love spooling much more now(or at least when the car has been running periodically!)
Artie

[CarSalesman]

Speedometer on my 95 S4s works fine.

[bharper]

Don't let your speedo hear that carsalesman! I have a feeling they all pretty much fail the same way, just in a different amount of time.

Thanks for the heads up ArtB, yep, would love to grind on the head, but not this trip. It would be down all winter, and this one needs to stay running. Still waiting on a few of the parts to trickle in, and the big service starts. Thanks for the tips on the coil packs and the silicone hoses!

Brian

[Sanj]

The S4s speedometer is not the same unit as those installed in the '88/'89/SE/S4 cars.

[CarSalesman]

Sanj - is the S4s speedo physically a different construction, or just a different background?

[Sanj]

Pre-S4s cars have a VDO mechanical speedometer, S4s cars have a speedo made by Caerbont. I think the S4s speedo is driven electrically rather than mechanically, but others may wish to correct me.

[ArtB]

I am sure Jim Knowles would know the distinct differences and I recall it being discussed in detail along with a "cruise control" thread, several years ago. I believe the S4s uses the VSS signal and is an electrically controlled Speedo, versus the straight gear driven earlier SE models like mine. Jim??
Artie

[LantanaTX]

While we are talking about Speedometers... My speedo with the engine off reads about 40, If I tap on it is will drop to zero. driving 40 reads 70-90. On and off the gas makes it jump to all different speeds. The odometer seems to work just fine and tuns smoothly. The PO included a new cable with the car and said years ago the car did the same thing and changing the cable fixed it. I am just having a hard time seeing how a bad cable still allows the odometer to read correctly and with the key off and stopped the speedo rests at 40.

[ArtB]

The mechanical speedo's are notorious for going wacko. There is a magnetic pickup inside the guts of the speedo that over time falls from it's mounting point. Travis (AKA Vulcan Grey) had a write up on the specifics and I recall he had documented fixing this himself. I sent my speedo in to a speedo shop in PA a few years back and still works great. It cost about $150 to $175 if I recall. Of course my car has only done 2500 miles since it was repaired, but that's another thread somewhere else!
Artie

[89.5 Esprit SE]

Originally Posted by bharper

Ok sports fans, is the speedometer needle itself still magnetically driven on a 95 S4?

Needle jumping all around, and not close to correct. Plan on pulling it tomorrow, since the headlight service dominated today. Seems to match the classic loose magnet syndrome.

Brian

The speedo is mechanically driven from the tranny. The cable screws into the back of the speedo on one end and into the right side of the tranny on the other.

Randy

[lotus4s]

Art and Sanj are correct, S4s has an electronic speedo and all earlier models are cable driven.
It does sound like your problem is not the cable but the speedo itself and the magnet fix...

[ArtB]

Thanks Jim, I knew you would chime in soon! Wasn't it you that installed the cruise control? I have one sitting for the last few years to install, but the car hasn't run long enough without problems to install it yet!

[G8nightman]

Can you post the thread to the magnet fix?

[LantanaTX]

Originally Posted by G8nightman

Can you post the thread to the magnet fix?

Would the magnet fix apply to both electronic and cable driven speedo's??

[Vulcan Grey]

Originally Posted by ArtB

The mechanical speedo's are notorious for going wacko. There is a magnetic pickup inside the guts of the speedo that over time falls from it's mounting point. Travis (AKA Vulcan Grey) had a write up on the specifics and I recall he had documented fixing this himself. I sent my speedo in to a speedo shop in PA a few years back and still works great. It cost about $150 to $175 if I recall. Of course my car has only done 2500 miles since it was repaired, but that's another thread somewhere else!
Artie

I've repaired my speedo since it was jumping around and saying I was doing 140 through town. The magnet had shifted so I glued it back down with wicking Loctite.

I didn't write it up though... S4 Simon did Speedometer problem - Engine/Ancilliaries - The Lotus Forums

I previously had mine rebuilt professionally, but apparently they did not glue the magnet in place, so it failed again.

[jtrealty]

The magnet repair only applies to pre-S4 mechanical speedometers. If the mechanical speedo is reading anything above 0 when not moving, the head needs to be removed for repair. If it bounces while moving it is probably a cable problem. It is not unusual for the electronic speedometers to not read zero when the ignition key is off but it should go right to 0 once you start the car. The electronic speedometers tend to not be set accurate. They can be recalibrated without having to remove them. I had to recalibrate mine. Best procedure involves running a measured distance using mile markers on a major highway. The longer the measured course the more accurate you can be. From the factory they tend to read a little faster. Also has the effect of accumulating miles quicker. Tire size, tire pressure, and wear will affect calibration too. The S4, S4s, V-8's and all following cars have electronic speedometers built into the Engine Management System.
David Teitelbaum

[ArtB]

Sorry Travis, I thought it was your write up. Either way, I knew you had fixed yours!

[bharper]

David,

Sanj seems to indicate the electronc speedo's started with the S4S, not the S4, and that the S4S and later cars went to the Caerbont unit instead of the earlier mechanical VDO.

I have not pulled mine yet, I need a day or two away from the project. After coming back from a test run the other night, I was quite thrilled to find the roof was no longer making any noise, and the car was perfectly quiet. Then the next day I discoverd the passenger window part way down, crooked, and partly out of the track. Yet another unexpected task on the list. I know, it is a lotus.

Anyway, my car was built in Sept94, registered as a 95, and it certainly does have a vdo speedo in it. Does the setting at 30mph deal when the car is running, and jumps up intermittently when giving it some throttle. That seems to match the vdo mechanical magnet problem.

Brian

[Vulcan Grey]

Originally Posted by lotus4s

Art and Sanj are correct, S4s has an electronic speedo and all earlier models are cable driven.
It does sound like your problem is not the cable but the speedo itself and the magnet fix...

Small correction that only matters to the 20 people who have X180-R's... The 1991 X180-R has an electronic speedo, and the transmission casting does not have a hole for the mechanical speedo.