Cam for Weber Carbs

Hmmm maybe my english is not good. Sorry for this!
I search for a camshaft wich works good with 48ida's .
Can somebody help me ?

Hi Peter.

We had a guy here (PanteraDoug) who runs Webers and I think I recall him posting about cams for them.

Try the search function.

He used to post a lot, so it might be hard to find the real detail you are looking for.....

Rocky

Here is a link to one thread on Webers....

Weber IDA/IDF Thread...

The Webers are fine on the street once setup correctly, I think the negative press is from people who buy as set, bolt them on and expect hem to work out of the box. They will not and require a lot of initial tuning to your particular engine setup.

I suggest to buy one of the Weber Tuning Manuals and read thoroughly, this website also offers some good advice for free;

http://www.timsroadster.com/html/tuning_webers.html

Julian

Peter,

I don't know if your application is street or racing. My reply shall focus upon street applications.

Every single cylinder motorcycle, every gasoline powered lawn mower, every 4 cylinder sport bike with 4 carburetors, every two cylinder motorcycle with twin carburetors (BMW), every gasoline powered generator, every chain saw, etc ... ALL are equipped with individual runner induction. Ferrari, Maserati, Lamborghini, Porsche, Aston Martin, all were once equipped with IR Weber carburetor induction. There was even a Ford Rally Race car available off the dealership floor with individual runner induction utilizing IDF Webers. Its not an impossible induction system, it just requires proper engineering. When you search for info on the internet you have to sort the BS from the good information.

There is a Pantera owner in Texas whose Pantera motor is equipped with IDA Webbers, he has no drivability problems. John Taphorn (member name JTPantera) may be able to put you in touch with him.

For the street the cam should provide low overlap, fairly well centered around top dead center, and reasonably early intake closing. This helps minimize any "reversion cloud" issues, which are the main stumbling blocks with using IR carburetors on the street. Such "reverse pulses" are exacerbated by IR induction because of the lack of a plenum to dampen and minimize such pulses.

My preference and recommendation would be to use the IDF carburetors, not the IDA carburetors. The intake manifold for IDF carburetors is available from a business in Australia named Aussie Speed, but it is imported into the US by a business in Texas named "Small Town Speed". I don't know if there would a more direct route from Australia to Germany.

quote:

Originally posted by George P: .......My preference and recommendation would be to use the IDF carburetors, not the IDA carburetors. The intake manifold for IDF carburetors is available from a business in Australia named Aussie Speed, but it is imported into the US by a business in Texas named "Small Town Speed". I don't know if there would a more direct route from Australia to Germany.

http://www.ebay.com/itm/Aussie...AOSw3mpXFQaB&vxp=mtr

The seafoam colored Pantera with the sorted Webers is (was) owned by William King. William lived in hill country Texas and we haven't heard from him for several years.

At the time, the irony was that his weber inducted car drove wonderfully, while pundits on the forums would maintain that you would never be able to get Webers to work on the car. It frustrated William to no end and he eventually gave up trying to convince them. I drove the car at an event we staged at Texas World Speedway and the Webers were great. No stumbles at all.

I'm running IDA Webers on mine. Pantera Doug has helped me a lot with tuning. I've got no complaints with how they drive. There are no chokes so they are a little lean for a few minutes until it warms up. Snappy acceleration with zero hesitation in the throttle response. After a bit of carb tuning and ignition tuning I don't even get the notorious weber backfires but I have super long primary headers which probably help.

Julian -

That's a really interesting thread you posted.

I like how he runs through the carb step by step.

According to my perusal of some of the old PI Mags, Dave Adler (Whiplash) ran Webers, and had good luck with them. There was an article about a guy named Augie (Doggy?) that talked about tuning.... It was an interesting read as well.

Rocky

thanks a lot for your answers,
I have allready the 48ida´s.

I bought an old gt4 project and they were includet, but all is dissambled and some parts were sold by the previos owner of this car.

He sold also the block, because it was a race engine build by detomaso factory.

I found a new 2 bolt block but I do not know, wich camshaft I should order.

I guess, that the 48ida´s have allready the right setup, because they were mounted in detomasos factory. So my idea was to use a camshaft wich have nearly the same specs. like they used in the past or a camshaft wich work with the webbers.
thanks for your help

BTW I am running the Crane roller:

crane 529721
276/284 seat to seat
214/222 .050
.562/.586 lift
111 center

This engine was set more as a tq engine and I have thus been quite happy with it. Very strong down low.

It has been helpful that the ignition I am using is easily tunable. I am using the Electromotive XDI. The controller runs under my console:



The initial timing knob sets the timing between 400 and 1000 rpm with a range of 0-30 degrees.

The 3000 knob sets the amount added linearly from 1000-3000 rpm

The 8,000 knob sets the amount added or subtracted from 3,000 to 8,000 rpm +/- 12.

The last knob is an RPM limiter.

I think several other types of ignition do this as well but it is real easy to fine tune.

Here is the coil packs on the rear firewall:

wow - this is realy nice !!
I am so sorry 2 days ago, I ordered a new Ignition set with a distributor :-(

Do you also have the problem , that the engine runs only on the "rich" side at idle ?

A friend of mine use hotter sparkplugs without resistor.

Do you think a hotter cam with only 108 lobe and maybe 0.7 lift is possible together with the webers ?

It would be worth leaving the back window out till you get the timing right. If you saw my thread where I made the back window removable.

I cannot advise you on the cam. I simply don't have enough experience using them. I am not going to arm chair coach from something I have read but not done.

Pantera Doug might be able to help as he has a lot more experience using them then I. I can only really say I am very happy with my set up. Like I said, I also have very long primary headers which I think is helpful.

As far as rich idle, I did at first. There are a couple of concepts which help you understand what needs to be done in tuning. First, you drive on your idle circuit. In fact, my brother in a different high HP car plugged the main jets as an experiment and took the car for a drive into town. As long as he was not racing the car, the car ran fine with no other changes!!!

What I love is jet changes are easy to make.

Your idle circuit consist of an idle jet and an idle air holder. When idling your fuel is primarily off the idle jet. When driving it's both. The mixture of the two set your driving mixture. sooo....if your idle is too rich, you lean your idle jet and enrichen your idle holder.

Your idle jet holder is actually an air bleed emulsion tube. To enrichen, you make it smaller.

I also have the 3rd hole drilled in the transition circuit. If you google that you will find step by step to do that.

These are easy carbs to work on whihc makes them fun. When I got them they were purple. I stripped them down and powder coated them and rebuilt them. They are fun carbs to work with.



What's funny is every time I come up to a car show people says "wow what a great injection system!". I think Hm, you're the guy who bought a 2016 corvette and brought it to a car show!

Also, if you can run it on an engine stand it's easier to get the carbs in sync as well as a few other things such as setting up your timing.

Very nice! I wonder if that set up would fit my C-302B heads?

I wish Indiana was closer to Houston, I'd like to borrow some time on that stand! Very nice.

If you were here you could use it.

Chris, The intake is the Hall intake. I have a 400 which pushed the heads out a little. Without doing anything it worked with 1 inch spacers. However, I cut the intake in half and removed the center section. If the ports would match your heads you could do the same but I have no idea about the ports.

quote:

Originally posted by pantera chris: Very nice! I wonder if that set up would fit my C-302B heads?

What deck height and block style are you running?

Best,
K

I am interested in the 400 M ? Did you dyno it?
FYI I run a earlier version of the electromotive 4 coil crank trigger and after 20 years no problems. Buy the way I solute your innovative headers and muffler set up, very nice.

The engine was built by Tim Meyer. It is stroked to 434. I wanted it to be more of a low maintenance torque engine then a high review engine. On the dyno we got 494 hp and 534 tq. We got 434 tq at 2000 rpm.

Some talk about the 400 fmx because it has the same bell housing. Soon you realize that's a silly choice because the FMX blocks are so rare.

Quick time makes a bell housing but the zf is inverted. It just needs to be Re drilled.

Btw I limited rpm to 5500 for durability.

quote:

Originally posted by Rocky:
Hi Peter.

We had a guy here (PanteraDoug) who runs Webers and I think I recall him posting about cams for them.

Try the search function.

He used to post a lot, so it might be hard to find the real detail you are looking for.....

Rocky

Here is a link to one thread on Webers....

Weber IDA/IDF Thread...

I can't think of anything that hasn't been said here already on the subject.

The 4 x 48ida is intended as a competition induction but it has enough flexibility to be streetable.

It will run with virtually any camshaft irregardless of whether or not it was designed specifically for them or not.



If you are asking me, I find that this is a "package" along with the cubic inch displacement of the engine, the flow characteristics of the cylinder heads, the changes that headers make and the usage of the vehicle.

TO ME, this is a vehicle, engine and drivetrain that is aimed at about a 6,800 rpm peak in top gear, produces power and response from off of idle to just over the peak rpm and fits the performance capability of the original chassis concept and the vintage maximum performance of the era.


For longevity there are a couple of things one needs to do. One is to provide vacuum to the engine through a pcv system.

The other is to lean down the idle system with current idle holder jets and idle fuel jetting.


Camshafts are just going to be a preference thing. Every racer had their favorites. Every street driven car will have it's own desired characteristics. "You" have to work that out for yourself.

Some people are just going to be "happier" (but not necessarily happy) with an EFI system BUT having said that, no one can explain to you what the differences, the compromises and the misconceptions of what induction systems like this are about.
Only "you" can determine if they are all "worth it".


I matched the camshaft to the head flow characteristics. The reversion is secondary and to me not a significant issue at all. The headers are also "theoretically" matched to this.

I used the "Gp4" car configuration as a guide, and worked from there. Others will have their own theories based upon other factors.

Having said all of that, the issue still remains, "people just don't realize what to expect from the Webers and many are just disappointed".


A nice reliable iron 4v head 5.7 is going to put you right at about 550hp at about 6,000rpm. Good aftermarket heads (probably aluminum) will show about another 35hp.

Torque on both should show you around 495ft-lbs at about 5,000rpm. Strokers may show you more total tork but the big differences are going to be where the power comes in which is 1,500 to 2,000 rpm.


Personally I went with a Comp Cams solid lifter profile.
http://www.compperformancegrou.../store/merchant.mvc?
Screen=PROD&Store_Code=CC&Product_Code=32-239-4&Category_Code=F351MFTCM

Some will love it, some hate it, some say it is too much, some say too little.

It works for me with the criteria I set and within the known restrictions.


The 2" primary tube headers work well also. Some will argue they are too big. I'm not here to argue with anyone. They can go argue in the mirror with themselves.

Thanks a lot ! ☺