Independent throttle bodies or triple webbers?

readie

readie

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Hi all, heading says it really.

I am having my csl engine rebuilt with a few upgrades. Not wild just things like a cam and pistons etc.

Can anyone suggest the better route to go out of the two mentioned.

Things like
- relative cost
- relative reliability
- achievable power differences
- ease of installation

Thanks
 
For me it would have to be throttle bodies. If you're interested in keeping things looking period I'd suggest the Jenvey Heritage bodies.

More power, drivability and economy with the ITBs. Downside is more complexity and cost.
 
thanks for the responses.

I understand that Webers are/were period correct, but have been told of some horror stories in getting them correctly set up. Somebody then mentioned ITB's as an alternative.....

Any other points of view ?

btw NOS - nice car collection, you just need to swap the rs turbo for a saab turbo......!!
 
3/4 match isn't bad!

Heritage ITBs
https://store.jenvey.co.uk/throttle...e/heritage-twin-tbody-40-48mm-triple-tdt40-48

Omex ITBs
http://omextechnology.co.uk/page239.html

Webers
https://www.demon-tweeks.co.uk/Prod...-6G6hhfujVfjou-gQFYaAq3CEALw_wcB&gclsrc=aw.ds


Interesting that the OMEX bodies are actually cheaper than the Webers by about £300, although factoring in injectors would offset that, obviously then you need the management. I'd budget £2500-3000 for a properly sorted FI set up.

As for the Webers being hard to set up, with a proper tuner that knows what they are doing, or with a good understanding of how they work, they're not a giant pain. Usually tuning issues crop up when they are incorrectly specified for the engine/ old eaky gaskets and o rings etc.
 
with webers you are not in the dark.... here are enough members with triple webers who know the settings , which will be sure a good start to get the car running . You only need a Lambda sensor and gauge. Driving it you can see the A/F , in what region rev's etc... and adjust from there jets according spec's from Weber.
Ofcourse you need to calibrate the throttles among each other , but that is the same with ITB's.
Temp can be measured on the headers tubes to see that they are +/- equal , so you check good ignition on all 6 and also no bad carb.
One advise from my race mecanic was to buy new webers , so you have the same .... never second hand.
At last it is ofcourse favorable to have acces to a range of all jets and tubes.... so you don't have to buy them just to do a test....

and IMHO fake Webers as ITB's ? nogo.... if you want ITB's, show them!
 
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Keep in mind that those carbs will want re-tuning with temp and altitude changes.
Seattle in the summer is a huge difference from Vegas in the summer.
I tried tuning 6 Weber’s on a 365 with Daytona cams and fell flat on my face in summer heat.
With FI and a laptop it’s 30 minutes of updating and you are done.
One vote for ITBs
Last month I tuned a 325is e30 with MS and ITBs for CoupeKing
240hp.....
 
sfdon has a point ... which we , here in Belgium, don't know... we drive between 0 and , if we are lucky, 25 degrees Celcius and all is almost sealevel. So no real worries about that

And i'm biased, i like oldtimers just because of less electronics on board....:)
 
Belgiumbarry said:
sfdon has a point ... which we , here in Belgium, don't know... we drive between 0 and , if we are lucky, 25 degrees Celcius and all is almost sealevel. So no real worries about that

And i'm biased, i like oldtimers just because of less electronics on board....:)
Click to expand...

If the Weber’s aren’t super highly Optimized for highest rpm HP then I think they are very actually fairly tolerant of altitude and temp changes. Yes they will run less optimally but they will run fine for street use. I have an Alfa 1300 with DCOE’s that is tuned to make the most power between 5500-8500 rpm. Yet last week it started right up in 14 degree F weather (required feathering the throttle for about 2 min before idle was stable/robust. It drove just fine as long as I kept the revs up (true in warm weather too). My old E3 drove from sea level to boulder CO without any change of jets/chokes. A quick tweak to the idle setting and it ran just fine all the way up to Leadville (10,000 ft). My 2002ti with DCOE’s ran fine all year round in MI with no tuning changes. Were these in optimal tune for all these conditions? No, but none were so bad as to exhibit drivability problems.
 
I have triples and once set up with the AFR meter (a big advantage now vs. back in the day with seat of the pants tuning of these) they are stable. Drastic temperature changes for me (95 degrees F in summer, 35 degrees winter only requires an air corrector change if you really want to be picky, and if not for the AFR meter you'd probably not notice the need, certainly for a casual weekend cruiser. Idle AFR might change a point or two, no big deal. Racing is a different story. I agree also on either buying new or professionally rebuilt (if you want period correct Italian webers) from someone like Alfa1750 on eBay. Don't use soft mount gaskets, not needed on our smooth 6 cylinders. And I found the 5 blade fan to create a weird turbulence which caused #1 barrel to dump fuel from the main jet stack prematurely, took me months to figure this out. Solved with the 9 blade fan upgrade.
 
Stevehose said:
I have triples and once set up with the AFR meter (a big advantage now vs. back in the day with seat of the pants tuning of these) they are stable. Drastic temperature changes for me (95 degrees F in summer, 35 degrees winter only requires an air corrector change if you really want to be picky, and if not for the AFR meter you'd probably not notice the need, certainly for a casual weekend cruiser. Idle AFR might change a point or two, no big deal. Racing is a different story. I agree also on either buying new or professionally rebuilt (if you want period correct Italian webers) from someone like Alfa1750 on eBay. Don't use soft mount gaskets, not needed on our smooth 6 cylinders. And I found the 5 blade fan to create a weird turbulence which caused #1 barrel to dump fuel from the main jet stack prematurely, took me months to figure this out. Solved with the 9 blade fan upgrade.
Click to expand...
I never knew that about the fan. Have to watch for that when back together.
I have triple 45's on a modified motor and they went over some 10,000ft peaks in Colorado. Granted I had to downshift to 3rd most of the time to keep the revs up but made it ok.
 
Maybe an interesting auction if you choose the Weber path (NMNA)
https://www.ebay.de/itm/ALPINA-B2S-...2-3-0-CSL-CS-525-630-Solex-Weber/142671615425
I'm curious to see the auction result :) --> Sold for 5650 Euro.

s-l1600.jpg
 
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