With higher compression, headers and a cam, you are probably right in the ballpark at 36. I have piano top pistons, excellent compression, ported exhaust manifolds and a cam as well (not sure about duration) and I am running 34s. As I recall, the 36s will enable more airflow at the top end of the rev range, at the expense of low end torque.
WTB: Weber Triple Carbs
- Thread starter bwalvoord
- Start date
Maybe this idea has already been ruled out but, you could ask one of any number of shops that have lots of experience with DCOE’s on M30’s.
Of course, you should expect to pay a little bit for tho advice (or buy a starting set of keys and chokes from them), as they have invested tome and effort in developing their expertise. Decades ago I bought a starting set from Korman and it only requires very minor changes to yield a totally satisfactory DCOE that worked for me on the street and a second setup for the track. I think I spent less than $150.
Of course, you should expect to pay a little bit for tho advice (or buy a starting set of keys and chokes from them), as they have invested tome and effort in developing their expertise. Decades ago I bought a starting set from Korman and it only requires very minor changes to yield a totally satisfactory DCOE that worked for me on the street and a second setup for the track. I think I spent less than $150.
This is great advice. In fact, I'd already had discussions with my local shop resource (Kummrow Automotive), which is an independent bmw shop in our area. They may or may not have the depth that a shop like Korman has relative to this topic, but they did recommend the 45's, too. I agree that paying an expert a nominal fee for their experience and expertise has significant value. Although, it is nearly as fun to postulate and second guess here on the forum... :confused:bfeng said:
Fwiw, I would start a little small on the chokes and do the setup with a wide and O2 sensor. Starting with chokes that are too big can drive you nuts trying to get the transition smooth via jets when the real problem is simply lack of sufficient depression to bring in the main circuit. Once it runs well then you can try a bigger set and make an adjustment of the main circuit
I had Kummrow fix the seals at the back of the coolant pipes on my e39 when I was in the area visiting friends a few years back. They are quite good.
The suggestion of an O2 sensor is a good one. On SteveHose's recommendation, I am using this: http://www.innovatemotorsports.com/products/lc2.php
The suggestion of an O2 sensor is a good one. On SteveHose's recommendation, I am using this: http://www.innovatemotorsports.com/products/lc2.php