engine and drivetrain Weber Sidedrafts Wooohoooo

[resra]

Just wanted to add to anyone wondering to switch or not to switch to weber side drafts: I all my life driven 2002s with only down drafts like the 32/36, 38/38 and 40 DFAV simply because I got so scared that they are hard to tune or you need highly modified engine etc etc.

 

I tell you about six years ago I met a retired 2002 mechanic who changed it all for me. He told me a properly set weber side draft is more reliable than the down drafts and if you don't have a modified engine you can still run a set of 40s with smaller jets. And so my search began two years ago and I bought a new set from carbs unlimited and had them jet it before delivery I forgot the numbers. I could not believe that all these years what I have been missing. The performance is just not comparable! From feeling tired to burning rubbers on third gear, it was a total transformation.

 

Yes, granted I fouled out my plugs every 1k miles but I didn't drive the car daily and so I was fine with it. Anyway, those who are scared to try out please make the jump! Save up and invest into it I guarantee you won't regret. I will never ever go back to a down draft no matter how big a down draft it is.

 

I am about to rebuild my head because it is smoking and I will install a IE regrind cam. I will be installing 45s next. Boy oh boy.

 

 

[M3M3]

You really do not need 45s. Just properly re jet the 40s for the cam.

[resra]

Marshall, thanks for the input but I don't want to miss out the 45s! Who knows maybe this tired engine can burn tires in 4th gear with the 45s. I'm just excited.

[73touring]

You might find you lose torque with the 45s if the venturis are too large. The 40s are good for around 150 odd hp. Possibly more. I dont think a standard bottom end is going to pull anything like that. 130 at a considerable push and thats with a bit of a wild cam and practicly undrivable low down. Id seriously stick to the 40s.

[ArdenK]

I like my 40s, they really make the car come alive!

[ryansti]

The difference is huge going from a 32/36 to properly setup dual weber 40's. And they sound amazing! 

[resra]

Ryan, yes forgot the sound also. Now it just growls! I love it. Only problem I have is I have a very difficult time driving 20 MPH in school zones. I constantly have to shift into neutral and 1st just to coast and still very jittery. Throttle response is off the hook. I can't imagine getting stuck in heavy traffic.

[KFunk]

Thanks for not letting me be the only one that thinks its awesome to just bolt 40s onto a stock engine and going!  It's usually just a constant stream of people scared/complaining about tuning issues, of which I've never seen as being much worse than a 32/36 (or even better in some ways).  Even if they're way out of synch, no big deal, if you hit the gas they still take off like hell.  The extra fuel blasting into all 4 cylinders usually just overcomes all problems. 

I thoroughly enjoyed mine with a stock engine for many years, and now with them on the rebuilt engine with 292/9.5:1, they're still great, and I've still never had to change the jetting.  

I really should write down all the jet sizes from mine sometime, so others can use it as a starting point.  Mine were originally set up by a bimmer tuning company in the 70s/80s, and they must've known their stuff.     

[vinntagejoe]

Thanks, nice post! I've been on the bubble for some time, now I'll put this back on my list, start saving my pennies and increase my honey-do's.

[resra]

Kfunk, you are 100% correct. I think majority people who are scared of them are the ones that never ran a set like me! I don't know how many people I scared off telling them that No NO No don't do side drafts because all I read and heard was oh gosh. I even remember one time before I ever owned a tii that never ever buy a tii because they are a nightmare to adjust keep running etc! BS! If you have a Tii that has never been jacked with by people who claim they know what they are doing (they don't) then you never have to really worry about it in 100k miles!

 

Just open the owners manual and most of the tuning stuff to cure all your running problem is listed!

[AceAndrew]

Just wanted to add to anyone wondering to switch or not to switch to weber side drafts: I all my life driven 2002s with only down drafts like the 32/36, 38/38 and 40 DFAV simply because I got so scared that they are hard to tune or you need highly modified engine etc etc.

 

I tell you about six years ago I met a retired 2002 mechanic who changed it all for me. He told me a properly set weber side draft is more reliable than the down drafts and if you don't have a modified engine you can still run a set of 40s with smaller jets

 

I think your mechanic sounds pretty exuberant!  As for the INCREASED reliability I call shenanigans, perhaps EQUAL is more apt a term.  And frankly if you noticed a BIG difference compared to a 38/38 then that carb wasn't setup very well.  I'm all for enjoying the pleasures of DCOEs, just realistically.

 

Here's a great recent thread.

http://www.bmw2002faq.com/topic/152828-the-dyno-data-and-motor-build-thread/

[kbmb02]

Yes, granted I fouled out my plugs every 1k miles but I didn't drive the car daily and so I was fine with it. Anyway, those who are scared to try out please make the jump! Save up and invest into it I guarantee you won't regret. I will never ever go back to a down draft no matter how big a down draft it is.

 

I'm not sure if 'fouled-out' plugs every 1,000 miles means all is ideal. (Question: If it's running that rich, what is all that extra fuel doing to the cylinder walls and rings of your old motor? And the new one?) Tuning...

 

We're having fun with both downdraft and sidedraft builds:

https://www.youtube.com/channel/UCncRyC7BDUG1La7Iz9Z6k-g

[resra]

Well I'm fouling plugs out with the 40 side drafts because my engine has over 400k miles who knows! It is tired! So, I know I would have fouled plugs with 38/38 or 40/40 down drafts but I was tired of being bored driving the 2002 when it comes to acceleration.

[KFunk]

I think oil fouls plugs more than fuel.  Will switching to a hotter plug burn off more oil? 

[TobyB]

 

Well I'm fouling plugs out with the 40 side drafts because my engine has over 400k miles

Nope.  You're fouling plugs because you're burning a quart of oil every 1k miles

OR you're dumping a ton of extra fuel in there somewhere in the fuelling curve.

 

If you weren't fouling plugs with the downdraft, then you have a fuelling issue.

 

Sidedrafts are wonderful, vintage go- juice.  One of the wonderful things

about them is that there are 40 ways to adjust them....

 

...start by checking your float levels, and go from there.

 

t