TWM/Weber manifold flow

[Ron Earp]

Ian,

That SHO motor would be pretty cool - how large can they get? As I recall they were around 3.4L and 230-240hp, but could do more I'm sure with a real exhaust and cams - if obtainable. Cool motors!!!! Would be really neat to use one in a Lotus 7 or similar, but, they are not that small. The DOHC head is very large and when you get that joker in the open they are big, saw one at a wrecking yard and was surprised.

We've got to figure out some way around this weber problem. Seems the companies wish you to purchase the webers and manifold for about $3k USD, then you need roughly $1000 in parts on top of that to come close to making them work for anything over around 320 inches or so.

In fact, now I am wondering about some other applications too. All the companies list Weber 48 IDA for BB Fords - 460 inches and up! Loading them up with the largest chokes possible and running the numbers indicates that peak power will be at 5135 RPM - talk about a torque monster, this would be it, and something you don't want in a sports car. I've got a feeling there are a lot of weber setups out there running on cars that are much less than ideal.

Looks like to me, if you want to run webers and have a flexible system that can do low and high RPM operation by varying the chokes, you want to have a V8 that is 289 or 302 inches.

With the 289 you can vary chokes and have peak power from 5400 to 8100 RPM depending on what you select. With the 302 from 5800 to 7800. Once you get to around 331 inches or so you are limited to peak power to 7100 based on maximum choke size and at 347 inches you are limited to about 6800 based on maximum choke size.

Yes, it is simply an equation and I'm sure there is lot of slop since the equation to me seems very simplified. And I am sure your mileage may vary and some folks have great experiences despite what is predicted. But, it seems pretty clear you won't be running a BB to 7k with webers and not leave something on the table.

Ron

[Ron Earp]

Wonder how they got 700hp in this car:

http://www.gt40s.com/ubbthreads/show...328/#Post71328

Using Weber carbs? Seems unlikely given what this thread and the other has turned up on flow, venturi size, engine size, etc. That thing is 427 inches!

R

[Sandy]

Ahh yes the old "Wydomkr" I like that car. Price seems a lot less now too when I was looking at it.

Quote -
"Nearly 700 estimated horsepower"

How near? How much of an estimate? If they don't have a Dyno sheet it might as just read 'High Hp Engine' or something like that. Hard to say how well it works with the IDA's. But I'll bet your estimates from your calcs would tell given best case 48's and chokes would tell the story. In desktop dyno just pick "Nearly 700 estimated horsepower" for cam and heads [img]/ubbthreads/images/graemlins/1poke.gif[/img]

The nascar folks make crazy power with restrictors, and small carbs etc for years. You just may need to know the secret recipe, might be a lot harder to do with the webers due to the IR nature vs the manifold and small carb.

I have the TWM and 50mm bodies, and a potential for getting them on the dyno after the same engine with a carb/victor manifold but I'm not sure if the EFI tune is in the capability of the engine guys doing it but it seems needed to see how well the EFI vs carb would work. I don't have any webers or would give that a try too.

Sandy

[Russ Noble]

[ QUOTE ]
I don't have any webers or would give that a try too.


[/ QUOTE ]

Maybe in the interests of science, someone on here could lend you a set to try?

Regards

[Ron Earp]

Sandy,

Your motor was on the RCR thread right? If so that was a stoinking motor, more so than my own, plus it was dry sumped. It'd be good to test with webers.

How far are you from testing it? Do you want to dyno test it?

I am going to use webers, for looks and just because I wish to learn and do, and, it could be I could order a set and have you try them. If I can get a company to work with us (Top End would be a good starting place) then we could publish the results.

As for the NASCAR and restrictors and carb, I'm sure a lot of that is in the plenium volume, runner volume, intake runner volume, etc. As you say, they don't have the indivdual runner problem and if they did, my money is on it that they wouldn't be making 750hp.

Interesting way for them to advertise their car here too. List it on Ebay, join the forum, then post it in the Ebay section. I notice it is not listed in the Cars For Sale section.

[Sandy]

Ron -

The motor that is on the RCR section is the one that is mentioned in the Dyno section 618hp @ 7500 good to about 8500. I'm not too likely to mess with that until something goes wrong.

The other motor that I'm working on is one that was from collected spare part for my 65' mustang. It will end up being a 331" with the same cam as the RCR motor as well as rpm range target. Heads are the same Canfields that I'm using on the mustang now rest of the stuff similar to the RCR motor. Right off the bat can see how the Canfields do against the Victors.

With this motor my starting point for intake is the 850cfm Holley pro that is on the mustang and the stock super victor intake. To do some webers would probabally be pretty easy but I would not expect them to be able to do much in the way of tuning. That's my problem with the EFI. I'll give them a holler next week and see if they have any Weber or Haltech EFI tuning experience. If so then we could have a nice test bed. Maybe you could convice Steve at TEP to do both Weber and EFI tune and we could kill 3 birds with one stone!

By the way everyone have a happy new years!

Sandy

[Ron Earp]

Gotcha - that is a nice motor for the RCR. It'll be interesting to see what the rwhp comes out to be now that you've got the flywheel numbers.

Ron

[Russ Noble]

I just came across this post from a couple of years ago which seems relevant to this thread. I would imagine you'd be able to specify venturis and jets as well.


[ QUOTE ]

You might inquire about the use of Gene Berg's larger IDA flanged carbs. They make them in 48,50, 52, 54, 56, and 58mm sizes.
I've never used these particular pieces, but have used many, many other Berg parts throughout the years. Not inexpensive, but the best quality stuff you'll find. I've never went wrong with their parts.

http://www.geneberg.com/58ida.htm

There is at least one other VW racer that makes large bore IDA pattern carbs. I'd have to search a bit, but I remember his name being Jack Sachette (or something similar!)
Memoriies don't always survive the test of time so well!!

--------------------
Dave Wharran
ERA GT 2072 - 351C,EFI,direct fired,ZF-2

[/ QUOTE ]

Could be something worth considering for all the guys that want to run quad IDA's without losing any performance. Not sure if they will look quite the same though?

Regards,

[Ron Earp]

Anyone ever click on that link and have the page constantly reload? That is what happens on my browser, has done so for years too.

[Russ Noble]

And I thought it was just me! You can't seem to get to that page from genebergs homepage either. Any way, if you want more info I'm sure there will be an email/phone/fax contact listed there.

[Paul Thompson 'Hooligan']

Nope - me too! and seriously bloody annoying!! [img]/ubbthreads/images/graemlins/banghead.gif[/img]

[Peruch]

Jack Sacchette's website :www.jaycee-ent.com ,very good on IDA's mod especially boring to 51.5mm

[Ian K]

Try this link instead:

http://www.geneberg.com/cat.php?cPath=8_240_2841

He has 58mm RHS and LHS set ups (as well as 50/52/54).

Here's a link to all carb products:

http://www.geneberg.com/cat.php?name...retion&cPath=8

Looks like he updated the site in Jan 2005 to use php.

Ian

[Ron Earp]

I've got an email out to Jaycee on prices and suggestions. Some 51mm carbs might do the trick.

Thanks Ian, that is helpful, but they ain't cheap! $1000 per carb, x4, ow! I suppose only a little more than the complete set of 48 IDAs though, but those come with a manifold.

Ron

[Sandy]

I looked at the Berg carbs 50mm+ too, but then get a peek at the price, each are ~$1k at that point seemed really out of wack with the TWM EFI setup.

Ron, I have not had a chance to give the Engine guy a call and see if he has any weber or EFI tuning experience, but a as an interesting note A fellow that I just hired at work has been a personal friends with Steve (at TEP) for many years, so if you want to try to twist his arm from your side (Getting webbers going), I'll see if he may also be interest in doing an EFI tune as that motor goes together.

Sandy

[Ian K]

Kinsler also offers Weber replacement throttle bodies for
IDAs and IDFs in 50mm sizes.

Not sure on cost, and their EFI manifolds come in a variety
of sizes as well.

Ian

[Ron Earp]

Hey Sandy, this came from the fellows that 289 posted. Not too bad on the prices, just over $1300 to "fix" them all.
----

Your problem can be cured by a few simple steps , if its air you need we can bore your carbs to 51.5mm and install a larger venturies.
On the V-8s its is common for them to run the carbs low on fuel and that can be handled by inlarging the float bowl.

Boring R&R carbs $375.00 per pr.
Fuel and float bowl mods $75.00 per pr.


Thanks Jack

>From: "Ron (Home)" <rlearp@gt40s.com>
>To: <dragracevw@msn.com>
>Subject: 51mm IDAs
>Date: Thu, 5 Jan 2006 10:19:43 -0500
>
>Hi,
>
>
>
>I am assembling a Ford SB (347 inches) for a GT40 replica. From my
>calculations, a 48mm weber with a 42 or 44mm choke is not going to
>handle my needs for flow. The engine will rev to 7800 RPM (cam peaks
>at 7500 RPM) and I don't want the power rolling over at 6200 RPM as I
>predict from venturi/flow/cylinder volume calculations.
>
>
>
>I read you guys can help out here - what can you do, what would you
>recommend, and how much will it cost? Thanks much,
>
>