Paxton vs webers...

[greenwater]

I've been fiddling with those two options for my 289 motor and don't really wich way to opt for. Maybe some could come with their inputs....

Money wise one can get a rebuilt vintage Paxton,as offered at the time by Shelby (for mustangs GTs at least not sure about cobras?) for about 2500.00 and webers (44 IDFs) with the manifold about 3200.00. Plus of course the xtras for each options.

The power gain seems to be definitely on the Paxton side with a claimed gain of about 30 % while the webers are to bring-in less H.P. Question: Am I right to think the apparent gain from the supercharger would be there only at higher RPMs and at contrary the webers would deliver xtra power at all RPMs?....In a much shorter/direct way to ask what would just be more of a kick to drive?

The use of supercharging apparently carries a constant dammage risk to the motor if detonation is not well under control at all times.....isn't a similar situation with webers carburation? If not for detonation isn't there another concern about webers that oblige one to always worry about a right level of tuned-in situation?

Does anybody would know why the Paxton was offered on Shelby mustangs and not on the cobras proper? Is it it came after the cobras years? Or would it be that supercharging wasn't as efficient a system as webers cars when racing was the intended use?

After all considerations webers tends to have my vote...but gee that ole cobra paxton installation is kind of nice also....what you think?

[poorboy]

Ron;
I don't know much about supercharging, but I think you have to use lower compresson pistons, with thicker tops & rounded edges. Also I have heard the supercharger doesn't work well for road racing. The webers give instance throddle responce. The tuning is not all that bad. If you spend the time to get them right to start with you don't have to tune them to often.

Poorboy

[Cal Metal]

This is just a guess, but the use of Supercharging may have been prohibited under FIA rules for use with the Cobra in production class.

[greenwater]

Originally posted by poorboy

Don,

Taking good note of your comments . You confirm my suspicion about the neat advantage of having allways ready "on-the-tap power with the webers.

What do you run 48,44 IDAs or IDFs?
You wouldn't have your cam's durations? I was told my "lumpy" lunati roller 218 deg. in,226deg.ex. was no good for webers....O.K. I'm in for few dollars more for a new cam but can I keep the power I have if I switch to an equal duration cam??
Ron;
I don't know much about supercharging, but I think you have to use lower compresson pistons, with thicker tops & rounded edges. Also I have heard the supercharger doesn't work well for road racing. The webers give instance throddle responce. The tuning is not all that bad. If you spend the time to get them right to start with you don't have to tune them to often.

Poorboy

[cobrashoch]

greenwater- This is a very old question that comes up from time to time. I could only answer it with another question. What are you trying to do with your car? That alone will dictate the direction you will have to go in. Along the way though a few things can be added both pro and con though.
First, the costs of supercharging will approach the 3800$ by the time you get it set up right unless you can find a price reduced air pump in the first place. You will have to come up with a pressure box and a popoff valve to protect your engine to. Also true that a supercharger will create a whole plathoria of problems that will need to be addressed, i.e.- overheating,pre-ignition control,component strength problems , drive train issues and others. All of this stuff can be tempered by your driving skills. Sounds confusing doesn't it? That's why I always tell anyone going this way the first time to find someone with a track record here to lean on. For the non B.S. crowd this is the only way to go though if the rules permitt it.
Second the cost of the webber setup is pert-near the 4000$ if you can set them up yourself only. True they can be tuned to give instant engine response and another thing they wil do is end fuel starvation problems when going around turns fast. As for being a power adder though, todays electronic fuel injection will match the performance levels of a webber setup. Also carbs with mid range tuning (to replace power valves) will get you close with tuning.
Both systems have the " WOW " factor when you pop the hood with the supercharger appealing to the hot rod crowd and the webbers apting to the purests and the sports car crowd.
Paxtons have been around since the early 60's though somewhere in there they came from the old McCallic (sp) superchargers. Today Paxton and Vortec superchargers are both owned by the same company I am told. Lots of luck on you quest. cobrashoch

[MRITTER]

Greenwater

The cost of the kit is only a small part of the upgrade in my experience.

I put a twin-turbo kit on my FFR - 302 EFI. Even after the obvious upgrades such as 70mmTB, 73mm MAF, Cobra Intake, head porting, headers and F cam I wasn't ready.

Had to have 38 lb injectors ($350) and a 255 lph fuel pump ($130) and adjustable fuel pressure regulator ($50). Then there was the ignition controller ($400). I have the Jacobs that has an in-car control panel. I can tweak timing 0-15 degrees, change my rev limiter and most importantly set BOOST retard 0-15 degrees.

But, cruising in 3rd gear at about 2500 rpm, mat it and you will fight to keep you head from bouncing off the roll bar. As a buddy of mine says "It flattens your eyeballs"

Sure is fun.

Later,

Mike

[gsharapa]

I have had both Webers and a Paxton Supercharger on a small block Ford. The Webers were on a Boss 302. Very impressive looking and outstanding instant acceralation. Pain in the butt to setup, but once they are set they run great! Clearly they add some horse power but nothing like a Paxton will do.

The Paxton also has an impressive look. I had a Shelby Paxton (the one Shelby had on 65/66 Shelby GT350). I put it on a Superformance Cobra with a stock Ford 351 SVO Crate Motor. I had a bigger blower disc put in the Paxton to compensate for the bigger 351. If your using on a 302, the stock one would be fine. Mine pushed 10 PSI of boost vs the stock one at 6 PSI. Two things you need to do with a carburated Paxton. Electric fuel pump with a fuel boost regulator (Mallory has one). Also, a reduce retard ignition regulated by boost (MSD BTM). Don't need the ignition retard with 5 or 6 PSI of boost but you do with 10 PSI or more. I used the ignition retard because I had 9:1 compression which is about the max you can put a blower on. The stock Paxton will add 100 to 110 hp the bigger one will give you 130 or more at full boost. Took my 385 HP crate motor to over 500 HP, all bolt on. 10 PSI boost or lower you don't have to worry about breaking internal engine parts but if you go up in the high teens, 20 or 30 PSI of boost like a lot of the late Mustangs, you do. If you want to do a Paxton, contact Craig Conley at Paradise Wheels in Ca. He is the remaufacturer of all the old Paxton Superchargers and really knows his stuff!

[Delbecque]

As Paradise Wheels has no website....you can find original Paxton kits at Mustang Unlimited for 289 & 302 but no spare parts

[Jim Werth]

This thread started in 2001. Jim

[gsharapa]

Funny I saw this thread pop up today and said to myself I though I posted something about webers and paxton superchargers in the past and sure enough there's my post from 9 years ago. Since this post I had webers on a 1966 GT350R Tribute car and my opinion is the same as most. Both have the WOW factor but it really depends more on what you plan to do this your Cobra. It you plan to track it I personally think the webers would be better as coming out of the corners you have the instant acceleration down low. If you are just street driving and some drag racing I like the supercharger better as the boost really makes HP and sounds cool. The neat thing about supercharging at low boost ie; 8 to 16 PSI most everything is bolt on but with webers to get the same HP you need more internal performance parts. My post for 9 years ago talks about the increase fuel pressure and ignition retard you need with a supercharger but again all bolt on stuff...I did a real nice story for Superformance (SCOF) owners group on installing a old Paxton Supercharger on a Cobra which they published in their newletter and I think you can get a copy on their SCOF site if any one is interested in putting a old Paxton on a Cobra. Here are a few pics of the Paxton on my SPF back then and the Webers on my Mustang. This SPF with the Paxton actually showed up on Ebay last year for sale and still looked great.....