205 8v Gti With 45 Weber - Questions About Of My Setup

[andy0075 9 1 Cars]

Good Evening !

 

Yesterday i tested a lot of jets and venturis in my carbed 8V GTI and i wonder about my jetsizes!

My engine is built up new with a headskim of 0,8mm , a fully modified head, a 300° cam with 12,5mm max lift,

two 45 Weber, nice lightened flywheel, Quaife, gearbox of an MI16, and so on....

 

The ignition is set to 8° at 900rpm and 30° advance at rpm>3500

 

you can take a look here : http://www.peugeotforum.de/galerie/user/us...gallery_id=1227

 

In a lot of articles in this forum i had read that most people uses 36mm venturis, and as a starting point 145 mainjets and 180 air correction

 

In my car i have a wideband o2 senor installed and i tryed to get an AFR between 12,5 and 13,5 under hard acceleration.

 

With the 36mm venturis i started the test with 140 mainjets and ended with 170 mainjets. I was always much to lean!

About AFR 15-17 !

 

So i thought, maybe the airflow with the 36 venturis is to low and so i installed 34mm venturis.

 

With these i was much to rich, about AFR=10 with 145 mainjets.

 

So i stepped down and now i ended up with :

 

Venturi=34mm

main jet=130

air correction=175

emulsion tube = F16

 

The AFR is now perfect between 12,3 and 13,5 at every rpm. The car is running really nice ( 0-60mph in about 6,9 seconds meassured with an G-Tech )

 

But these jets sounds so small for me, also the venturi. Why everyone uses 36mm Venturis and my engine seems to be to weak for them ?

Maybe i did something wrong, i mean the 6,9 seconds are a really good time, but .....i don't know...

 

What are your thoughts about it?

 

cheers, Andy

Edited April 27, 2008 by andy0075