Choosing the right size of IDAs?

[Jøran Larssen]

I sure could use some advise about choosing the right size of carbs for my engine, and would like to hear your opinion before spending a lot of cash.

Engine is 2387cc type 1, CB Competition Eliminators w/48/40 valves, 10,7 compression, FK87 cam, MSD ignition.

I have allready got a set of 48 IDAs w/42 venturis, but have been looking at JayCee 52s and Berg 54s. The car will only be used for racing.

[Roman]

I have Berg 52's so that is something in between...
I broke my trans almost instantly 2 years ago with my Berg carbs but so far they have worked well.
What I have heard is that the Jaycee modified IDA:s is easier to tune than the Berg carbs.
But why are you limiting the compression to 10.7 if it is racing only?
Compression: Bump it up and hear it thump! Racing gas for racing cars!

[Jøran Larssen]

The original plan was to have the compression set to 11, but after messuring the heads, it seemed a bit waste of money to have them macined to accive 0.3 more, since they gave 10.7 out of the box.

My goal is also to race the engine on pump fuel, and to have the possibilty to put it back in to my Ghia later. The point is that I have only got one gearbox and engine, but two cars to choose from. This year I'm going to use the box and engine in Four Play, but who knows what I will do later ;-) 

[SOB/RFH]

12:1   and it will purr like a kitten....just for racing!! 12,5:1 or more........Compression is cylinderpressure and that equals to torque that is multipied by the revs.........high compression and high revs=lot's of horsepower!! Lot's of horspower = Raceengine!! Race engine=lot's of maintenance work and money!!! Happiness is a Hot VW!!

[Jøran Larssen]

Any opinions about carburator size?

[Roman]

Go for the Jaycees. The berg carbs are $1050 each and the Jaycees are $1400 a pair (you can often find them for $1000 used).
I doubt that the Berg carbs will give you at least $700 more fun!

[Jøran Larssen]

But still, if you put on your shades, and don't consider the price as an issue, what's the ultimate size of carbs for my setup? I still want to know   

[Petter Carlberg]

How big carbs you need depends on how much your heads flows. You must have great heads and a wild cam to have use for a set of 54´s. I think a set of 51,5 with 46 venturis can bring you home...

[SOB/RFH]

48 IDA:s are good for 240 hp.....most cars don't need any bigger of a carb. Most bored out carbs are hard to tune compared to the stock carbs.

[Roman]

Talk to to Tom Costello, brother of the late Pro Stock champ Andy Costello. He is very helpful and can supply you with any size of IDA:s, Berg Carbs or Terminators. All 48 IDA:s can't be bored out to 51.5 or 52:s as the idle bleed hole is positioned different in different carbs. Tell him your specs and he will supply you with a suitable carb. If you want to squeeze out that last CFM he can profile the butterflies, teflon coat the carbs, pre tune them to your specs etc. and all for reasonable prices.
He can even supply with custom size butterflies if you want to bore them out yourself. I think he said like $20 each for the butterflies 2 years ago when I spoke to him.

http://www.costelloracing.net/

[Jøran Larssen]

48 IDA:s are good for 240 hp.....most cars don't need any bigger of a carb. Most bored out carbs are hard to tune compared to the stock carbs.

That's what i have heard too. And that 51,5 carbs might give a little extra on the top. Lots of good feedback here now. Thanks guys!

[Jøran Larssen]

Here's something interesting regarding carburators:

New CSP 48 IDAs (made more power than 51s) on Welded Skat Trac manifolds

http://www.cal-look.com/forum/index.php?topic=9229.msg88021#msg88021

[Roman]

Sounds weird. CSP:s website does not anything about any new carbs.

[Georg/DFL]

CSP has no special carbs, they are just selling new IDAs, that's it.

[fast54vw]

i dynoed my 2332 with 48 idas and 45 venturies that i got form bill schwimmer and it made 225 hp with a 4 lifters breaking some where along the way. i never got  a good dyno pull but i bet it will make another 10 hp.
 i am puting the engine back together exactly the same but with jay cee 51.5 idas and 47 vents. i will let you know what power it makes when i dyno it.

vee dub parts has a good deal on 48 idas. they work with jack alot and have worked out some good deals with him. (recently a better price on modifying the 48s to 51.5) i work there and do most of the shipping and yes i ship almost everywhere. so if you need any thing email me and i will do my best to help you out.

[Jøran Larssen]

Thanks for the answers and hints. I have ended up using a set of 48 IDAs with 45 venturis combined with 180 gas and 200 air jets. Not much time to tune before Bug Run at Mantorp, so I will just have to use Bug Run to test and tune my setup. The plan is to start it up this weekend and leave for Mantorp on thursday. Cya there!