Exhaust mods

[SJW BASIRE]

Every so often people come on the forum asking about modified exhausts on an SC.Well today R15 had a Dynoday at Alan Jeffries in Plympton.I put my '80 model 188 hp SC with SSI's and a Dansk stainless '74 Carrera 2.7 2 inlet 1 exhaust silencer on the rollers and got 204.3 bhp and over 200 ft/lb torque.I also got a flat Lambda line throughout the rev range indicating combustion is excellent and the K jetronic is working perfectly.Needless to say I am chuffed to bits with the results.It sounded pretty awesome aswell!

 

[SJW BASIRE]

No, the air pump has been removed and I have no problem meeting the MOT CO emissions standard.I know some people go for a louder,deeper exhaust note and huge tailpipes but the beauty of the SSI+2.7 Carrera silencer option is that it looks totally standard,but sounds more like an early 911.Indeed it is so subtle that my mates were taking the mickey.They said "So you'll be happy with anything over 170 then?" The last thing they expected was 16hp more than standard!
All the 993+996 newbies were a little down, as is to be expected with age and a 997 PDK went into limp mode as the PASM couldn't be completely disabled and didn't like the front wheels being stationary while the rears were on the rollers.
Now I'm wondering to myself whether a new set of injectors would improve things a little more as I haven't a clue how many miles they have done[]

 

[nathan 1981 930 G50]

You could have your injectors checked/cleaned by a specialist as you want them all to flow evenly (matched).

 

[tscaptain]

ORIGINAL: SJW BASIRE
and a 997 PDK went into limp mode as the PASM couldn't be completely disabled and didn't like the front wheels being stationary while the rears were on the rollers.

It was actually the PSM/PDK combination that wouldn't play ball on the rollers, Steve, but I know that might be a bit technical for you SC boys![][] Outstanding result for yours, I thought - pick of the bunch.

 

[SJW BASIRE]

Thanks Alan!
The SSI's are supposed to extend the torque curve lower down the rev range rather than increase outright power, but when Crispin persuaded me to part with a rather large sum of money about 10 years ago he did say that they have an almost magical effect on the early low compression SC's like mine.
I told my TVR Saggyarse owning mate in Norfolk about the Dyno day and he said that when they did a similar event an Audi RS6 did the same thing as the 997 PDK. Computer geeks are spoiling all our fun!