[DeTomaso] Webers

[Patrick Hals]

I have been racing with Webers from day one, starting 2004, and it sure is a good choice. I retrofitted one of my engines with a 750 Holley carb, and it seemed like it gave more torque, but less power. The reason I did that was that I wanted to keep my Webers for a future engine to be built, so I put the Holley ( that I bought for 50 USD on EBay ) on my first replica GR4 and sold the car as it.
I still have the Weber set, complete, with alloy Hall Pantera intake, and would consider selling it, as I do not longer need them.  Synchronizing the set is indeed,  "a walk in the park" providing you have competent mechanic and adapted tooling. We adjust the Webers on a yearly basis, no more than that. Of course, you don't get the last HP , but I am fine with that. I check valves more often ( every race) . The noise is superb, but covered by the 180° exhaust ( no silencers... ask Mike Drew) . Still, a Weber carb system can be easily recognized, listen to a street Alfa Giulia 2000, or a street Maserati 3500 GT, in just one second, you hear the Webers sucking air.
Now, I read the wonderful and oh! so promising story of 8 or 9000 RPM. Will gives a very simple and straightforward response, it will run 8, or 9 or even 10.000 RPM, once, for maybe one or two seconds. That's it. Everything will brake, rods and pistons will crash through the engine, everything will be dead. That is an expensive solution !
Keep in mind the RPMs are a combination of numerous elements, the weakest will break first, and take his little friends to the party. Whether rockers, 4 bolts crank ( my crank has costed 20K or so, and is signed by the artist who has produced it ! ... ) valves, springs, rods, pistons... you just don't add RPMs by fitting Webers or racecams.
On Candy, I have a strictly legal displacement 351 C which produces 544 HP at 6250 RPM and 640 Nm of torque at 5100 RPM. We could hardly go above that with 10.1 compression ratio on street gas.
When I bought Candy in the USA, it was racing a stroker with 14.1 compression ratio, at 7400 RPM, solid lifters, 114 octane gas, 580 HP. It broke after 20 laps in Spa..., on 110 octane ( octane in Europe is a lot lower than the USA)  I decided to reduce the compressio rate down to 10.1 and race RPMs from 7400 down to 7000 to increase longevity, and most of the time, in a race, I shift gear at 6500 RPM, because it is useless to go higher. I lost 40 HP, but the engine is fast, reliable, and cheap to maintain. It will match a 935 RSR race Porsche at Le Mans Classic with no problem... Fast enough ?
On the ADA 9628 Le Mans 1994 racecar, we had no engine to start with. So I considered all alternatives within a reasonable budget.( all aluminium block and heads, fuel injection, titanium where possible, ... a modern race engine, 6sp sequential gearbox, ... ) street gas.
There's one very simple rule , according to my motorist :
You want to hit 8500 RPM regularly, with 750 HP or so : your engine will last for 10 hours max.
Your goal is 7500 RPM , with 700 HP, 20 hours.
7000 RPM, 650 HP, 50 hours.
Got it ?
So, 9000 RPM , 850 HP, : one second, and BANG.
Did I see you wanted to do this on the street , or on a track ?
Pat
2862 - 2342 - 9628 - 3679
www.detomasogr4.com


IDate: Sun, 26 Oct 2008 22:18:53 -0500
From: "Will Kooiman" <wkooiman at earthlink.net>
Subject: Re: [DeTomaso] Webers
To: "'boyd casey'" <boyd411 at gmail.com>, "'Bruce Rogers'"
<brogers at optonline.net>
Cc: detomaso at realbig.com
Message-ID: <71B0E7BBC5B448369AA5FC02919AB842 at LORETTA>
Content-Type: text/plain; charset="US-ASCII"

The Webers will remove most of the lope.  It will idle at a lower RPM, and
it will run smoother.  It will sound more like a Ferrari, but if you really
want that sound you also want 180 deg headers.

The biggest challenge is getting the linkage so that all 8 open at the same
time.  Once the linkage is right, tuning is a matter of using an O2 sensor,
reading about Webers, and buying 8 sets of everything every time you make a
change.

Even without solid lifters, it will rev to 8 or 9K.  Once.

-----Original Message-----
From: detomaso-bounces at realbig.com [mailto:detomaso-bounces at realbig.com] On
Behalf Of boyd casey
Sent: Sunday, October 26, 2008 2:26 PM
To: Bruce Rogers
Cc: detomaso at realbig.com
Subject: Re: [DeTomaso] Webers

Thanks, I don't know if I would bite, but if the price was right I could be
tempted. I just love they way they look and the efi "look alike" substitue
has some appeal  ,  it is supposed to improve  drivability and fuel economy
and increase HP  the cost  is *crazy money * $5900 and UP! *Thats half the
price of a new high performane engine*, and the set up seems extremely
complicated. Electric fuel pump, fuel return ( to name a few). They make
some cheaper ones but the do away with the fuel return and ae " preset" ( no
computer adjusting) that sounds to me likeyour giving up half the poetntial
for tweaking the performance . making things "foolproof" are normally
reserved for "fools". I have heard getting he Weber's synched and adjusted
properly is no walk in the park either ,none the less it has just always
appealed to me.

Do you know if  the Webers change the sound of the engine.? I have been told
my 351 Clevland is apparently  running a 3/4 race cam . I don't know for
sure because the previous owner is dead and there is no one to ask.  I have
not been "inside" the engine. It also has an aluminum intake manifold (
looks kind of like an edelbroke) and a Holley 650 wih a manual choke,  an
MSD distributor with an MSD 6AL module and an MSD 45,000 volt coil. The
exhaust looks like  Hall big headers and what looks like an ANSA type
exhaust ( i was told it looked like "Big Halls" . ( no rectangular mufflers
just the tubess get a little fatter at the end . They sound to me very much
like straight pipes. I had open headers on my boat and These are just about
as loud. I would  like having a higher reving engine and I was told that if
I installed roller rockers,  solid lifters ,and pushrods I could get my
engine to redline in the 8 to 9 K range.So I thought with the higher revs
and the quick throttle response of the webers I might get a sound more like
a european exotic ( ferrari,lambo etc.) plus better perfomance. Is my
mechanic blowing exhaust up my ass or is there any truth to  this?

Boyd 1973 L # 5783advisor



On Sat, Oct 25, 2008 at 6:52 PM, Bruce Rogers <brogers at optonline.net> wrote:

> If there are webers for sale post something to let us know, people are
> emailing me know to know if there are used webers out there for a 351c 4v.
> _______________________________________________