S1 135 Upgrade - Worth Getting?

[bermudabob]

As part of my ongoing hunt for my first Elise, I have encuntered a nicely priced S1 that has had a 135 upgrade performed on it by a reputable company.

 

Is there anything I should know about cars that have had this done? i.e. are there any known problems that might put me off buying it?

 

Rob

[Scott_Mac]

Nope, its all good.

 

If its the PTP one then it is the same as the genuine articel - but won't have the close ratio box etc.

 

Other companies offer upgrades etc, DVA etc.... so long as it is reputable, then no real issues with it. Only thin i have ever been warned about is that make sure it has the 48mm throttle body and not the 52mm version as the 135 head can run lean on the standard ECU.

[Steve J]

Hopefully not as prone to popping the Head Gasket like the Lotus S2 one is

[Scott_Mac]

I think it was just the 135R head that had that problem Steve... the "early" 135 upgrade seems to have been generally ok AFAIK.

 

Don't think the S1 135 was any more prone... probably cos PTP did it, not Lotus

[bermudabob]

Will the 135 have the same rough idle problem that the 160 has?

[Scott_Mac]

Nope the rough idle comes form the wilder cams as used in the S160

 

The head is actually the same, the 160 is further different by having the different (badly timed) cams

[Mr G]

I reckon it would be worth checking what gasket was used when the head was changed? If it was a reputable company - then they should have used a modified gasket to take account of inherent liner issues with the production engine. PTP and DVA both do these heads (and Janspeed?) so any should be able to confirm what gasket was used. I would suggest being very wary if the head was bought as a kit and fitted by an 'expert' - most problems with aftermarket heads seem to be because they have been fitted by people who don't really really know what they are doing and don't know inherent issues with the K. Can't remember what gasket you would be looking for - but modified Rover and Mike Satur (VVC K series expert) variants spring to mind.

 

Other than that, the only issues I am aware of are the throttle as outlined above and if it has too much power (circa 165 plus) then the OEM ECU may not be up to the job. AFAIK - a very decent 135 upgrade, done properly with a sports zorst and decent induction could do 150bhp but probably no more, so you should be OK (Emerald words, not mine)

[Scott_Mac]

The general rumour was the S135 had approx 145bhp, but wasn't labelled as such as it was cheaper than the 111S which only had 144 at the time.

[Mr G]

Didn't know it had that much!!

 

Wish I'd bought one myself now!

[Scott_Mac]

 

Was the car i'd always wanted Could never find one though....

[Mr G]

Was the basic difference the porting and the plenum rather than anything to do with cams and timing?

 

Also interested why the bigger TB might make it run leaner?? Can you not re-set the wotsit doing the throttle pedal trick to take account of that? hate to think what billowing pollution comes out of mine after iis surgery! - can't wait for its MOT!!

[Scott_Mac]

Yup, same cams as std....

 

I found out about the TB when talking to PTP about manifolds etc (if you've ever called you'll soon realise you can't get off the phone from Simon ) Apparantly the std ECU is programmed to run slightly rich, which is why the 52mm TB is a good upgrade as the engine/ECU can handle the extra air influx... however when you get the larger head into it, and consequently more power the engine starts to run lean - its basically the reasoning behind what you said above of the std ECU only being able to handle approx 160bhp

 

The pedal pushing thing, just resets the IACV and not the ECU.

 

If you are going to go with an Emerald anyway, then you will be ok to run the engine lean for a while, but if not - stick to a 48mm TB.

[Mr G]

MIne has a DVA 150 head on it plus decent induction and the 160Trophy TB - it was hanging on the revs for a while, until Dave A suggested a small restrictor (essentially a pice of plastic that looked like a chunk of an old man's pipe) was pushed into the air supply pipe that goes into the TB. Reset the IAVC and the thing idles fine now. Peak power about 165. Absolutely HATE to think what the emissions are like though!! I suspect to get it through an MOT it'll need a trip to Emerald in March/April time and I'll have to buy a lap top to switch between 'Safe mode' MOT programmes' and 'race'

[Mr G]

Are there any obvious signs that the engine would be running lean?

[Scott_Mac]

Sadly my techy knowledge ends with theory and what i've read up on....

 

I would guess a lack of power, not smooth running etc, but couldn't swear by it.