The 'E' Type Forum

Hi dear Jag fans, good evening, wish you ALL a very happy and promising 2015, with great realizations. Well, my 73 american version 2+2 cat was bought with no gulp valve installed, the one that comprises the bleed system coming from engine balancing pipes. I am facing difficulties in finding one of these gulp valves, so questions: What is the consequences of leaving system with no bleed valve installed? By the way, what is the function of this valve? Another issue on the engine is the lack of the air supply system coming from the engine air pump. Sorry if this subject has already been discussed in the past, I am very new in this hobby and know very few about these cars. Thank you for the understanding. Claudio, Florian?polis, Brazil

Dear Claudio,

The small tan coloured US Owners Manual covers all of the emissions equipment fitted to your car and explains its usage. Pretty much everything from page 84 onwards can be delted and plugged without affecting the car's performance.

The gulp valve simply admits a small amount of air into the manifold if you snap the throttle shut too quickly. Most cars don't even have one, so don't feel too worried that it is essential to the running of the engoine.

The air pump only pumps air directly into the exhaust to help oxidise exhaust gases - it has no effect on the engine.

kind regards
Marek

Thank you Marek.

The US-version of the EV12 had less power than the UK-version. Maybe also because of this anti-pollution system.
You can kick it all out of your car, without problems.
Regards Wolfgang Gatza

Wolf, Is yours also imported from the USA? Have you removed these anti-pollution devices? Grusse!

Wolf, cheers, is yours also imported from the USA? Have you removed these anti pollution devices? Gruesze, Claudio

My car is from USA. When I have bought it in Germany in 2001, the pre-owner had removed all anti-pollution devices.

Regards Wolfgang Gatza

"The small tan coloured US Owners Manual covers all of the emissions equipment fitted to your car and explains its usage. Pretty much everything from page 84 onwards can be deleted and plugged without affecting the car's performance."

I am also in the process of removing all of the emissions control devices from my S3.
Can anyone tell me where I can get a copy of the US Owners manual you refer to here please.

"Pretty much everything from page 84 onwards can be deleted and plugged without affecting the car's performance."
Wrong. The performance will go up. I have heard 20 - 30 ponies.
Regards Wolfgang Gatza

Oh really? Do you honestly think the smog pump consumes 20-30hp? If that is true, then removing the aircon and power steering ought to liberate an even greater performance gain.

kind regards
Marek

Hello Marek !
I don't think this, but I have heard it often. I am thinking, that the difference in power is less high.
How much is the top speed of an UK EV12 of 1973 ? How much is the tops speed of a USA EV12 in 1973 ? If I will get these numbers, it es easy to calculate the power to reach this speed.
Regards Wolfgang

Dear Wolfgang,

That would not be a fair comparison because the specification of the two cars was probably very different, e.g. differential, compression ratio, etc.

A fair way to make the assessment would be to take a US specification emissions car and run it (on a dyno) and then run it again with the smog pump belt disconnected. I would be surprised if the result were more than 1/2hp different. Consider that cars like a Sprite or Elan or Spitfire, which would have run similar smog pumps at the time, would have had an absolutely phenomenal performance gain if your original quote were true.

The tan owners manual is available in bookshops and often appears on ebay.

kind regards
Marek

Hello Marek !
All your arguments are correct.
Does anybody know, how was the tops speed of such a late EV12 with all the anti-pollution system ? Is it possible, that this was roundabout 135 mph instead of 145 mph of the Uk-car ?
Regards Wolfgang Gatza