best weber kit

jimbo · 12-25-01, 05:13 PM

I am starting to gather the bits and pieces for my engine for a GT40; basic engine will be a crate Ford Motorsports 5.0, with their GT40x heads, E303 cam- fairly mild, since I want a street-driveable car. I would like to use Webers. I have looked at several sources for a complete Weber kit; Pierce, Inglese, Rotary, and Carbs Unlimited, I think it's called. Here are a few questions, if anyone has time to write in about their experiences...
For this size motor, 44 or 48 IDF?
Any advice as to who to go to, particularly sources other than the above, in the USA?
Best manifold, best linkage? (I have seen manifolds advertised by all of the above and also Holman Automotive)
Vacuum advance ignition versus mech advance, with Webers?
There is much expertise among Forum members which I don't have, and if I can I would like to avoid making too many mistakes in putting this engine together. Thank you in advance,
Happy holidays,
Jim Rosenthal

Wayne Presley · 12-25-01, 08:16 PM

What's wrong with injection?

12-26-01, 03:16 AM

Jim,
Have you already purchased the GT40 heads? If so you may want to reconsider as they are right near the bottom for horsepower among all the aluminum heads. The best head at the current time is the Air Flow Research, it gives about 40 more hp than the GT40 head. A close second is the Trick Flow, twisted wedge.

EFI is harder to tune initially and more expensive, but once tuned stays that way. Webers need periodic maintainance and tuning.

Probably the 44 for a mild street motor.

Hershal Byrd · 12-26-01, 10:05 AM

Hi Kalun,
I think you are right about the heads, although I also think the Edelbrock Victor Jr's are an excellent choice. Their flow tests are right up there with the others.
I have had weber carbs for 15 yrs and they are fine if you plan on staying at the same altitude. But if you go to a higher altitude they will drink gas like crazy and start popping and running ruff. The EFI is by far the best way to go. There is a learning curve involed for proper setting but once learned it becomes very simple. I have EFI on my Cobra and I wouldn't go back to webers for nothing. The system has been great for the last 6 yrs. True, there is a higher price to pay for the EFI but it's well worth it in my opinion.
I think Wayne Presly has the best all around deal for this setup. You might want to call him and find out more.

Hersh [img]images/icons/smile.gif[/img]

Brian · 12-26-01, 11:27 AM

Wayne, can you provide us some details for your injection set up? I would like to use EFI, but the factory stuff is really out of line in regards to what I want for appearance. Yours looks impressive. I am also interested in utilizing a FoMoCo crate motor with a good cam and some nice heads, nothing overboard. Is it correct to presume that this is a mapped system rather than mass air flow? Do you have a little sheet which you could send which details what is included,how to tune, etc? Thanks, Brian

12-26-01, 12:58 PM

Just a suggestion, anyone looking to build an engine based on a Ford "crate motor" needs to look at the final completion price, both in time and money. These engines look very inexpensive on the surface but by the time you remove the parts they supply and replace them with what you need, you generally end up spending more than the cost of having a quality engine built. We have had many customers go down the crate motor build, only to come back after it was all over wishing they had bought a complete running engine.

12-27-01, 01:19 AM

For the initial build, I am using stock EFI on a 5.0L. The only upper plenum, again stock upper and lower, that will fit is the 94-95. I am using a larger Pro-M air flow meter. I appreciate the opinions on heads, but are you guys considering drivability on the street?? Some high performance heads, and other parts like intakes, won't give good drivability on a 5.0L; just something to keep in mind. The setup that Wayne showed with Motec ECU would be hard to beat for looks and performance!

Wayne Presley · 12-27-01, 03:51 PM

The injection manifold is $2400 complete and assembled with fuel rails. You can run any speed density (MAP sensed) computer you want but I'm using (and selling) the Electromotive TEC II system for $1950. The TEC II comes with the coil pack direct fire system so you need only to buy spark plug wires to finish the ignition system. The MoTec system is the best system out there but is overkill and expensive. They use the MoTec in Austrailia because they have to still meet emission regs on every car and the MoTec will do everything but tie your shoes for you.

12-27-01, 05:05 PM

Here are some pictures of a TWM induction system (Nice quality good linkage) on my FFR roadster I used the Speedpro speed density computer with this system. The engine is a 351 windsor but they make intakes for the 302 block as well. The Motec system is the nicest but as Wayne mentions it aint cheap and is a bit overkill. See pics at
http://members9.clubphoto.com/rich50...ner-cecd.phtml

Good luck Rich

Gordon Levy · 12-27-01, 07:23 PM

Once I learned how to use it the MoTeC is fabulious. I swear it will tie my shoes also. One of these days I would like to put 8 wide-band O2 sensors in and try the individual injector timing.

12-30-01, 02:25 AM

Wayne, I must confess that I was thinking of the Electromotive system when I said Motec. I t has been quite some time since I researched the various ECU systems and was confused. I talked with Electromotive guys back then and it seemed to me that they said their system would also do mass flow--For those guys who would use a plenum rather than stacks. It would ruin the look to put a plenum on top of those stacks!-- and close loop as well. Or, am I miss remembering again?

12-30-01, 09:32 AM

On Weber carbs, something I don't have being a single holley kinda guy, I have heard problems being experienced by having the wrong type. One type is the IDA and the other is the IDF. Which one is the wrong type I do not know but those guys here who tried the wrong ones had all kinds of problems with fuelling and spit backs etc. This is why I guess everyone loves EFI. Keeps the looks but not the problems. You may want to find out if the 44 IDFs you mentioned are going to be ok. Sorry I can't be of more help.
Malcolm

Wayne Presley · 12-30-01, 12:04 PM

The Electromotive will do mass air, MAP sense, TPS only, blended TPS/MAP, and closed loop in any mode.

gheacock · 01-02-02, 10:08 PM

I might suggest keeping it really simple initially. If you are just finishing your car you will have so many other issues to deal with, suspension, transaxel, (shifting linkage), brakes... so many things. If you haven't "done" webers yet, put it off. Start your car with a 750cfm or 780cfm carb (Holly or Demon) mated to an Edelbrock intake manifold. Use a factory spec vacuum advance distributor. It will cost you $350 -$450. Then, when EVERYTHING ELSE is sorted, sell the 5.0 carb setup and dive into the Webers. This willl also establish a performance baseline. P.S. you will probably not like the Webers much initially... be patient.
Regards Greg