mgs
[Top] [All Lists]

Re: SU's vs Webers when converting a rubbernose

To: "Rick Morrison" <gofastmg@juno.com>
Subject: Re: SU's vs Webers when converting a rubbernose
From: "Mike Gigante" <mikeg@vicnet.net.au>
Date: Fri, 27 Nov 1998 13:44:26 -0800
Don't worry Rick, I didn't take it as a flame. I do think there has been
enough of this topic though!

As a matter of course, I always use a rolling road dyno after each change -
seat of the pants doesn't cut it really!

cheers, Mike

-----Original Message-----
From: Rick Morrison <gofastmg@juno.com>
To: mikeg@vicnet.net.au <mikeg@vicnet.net.au>
Cc: mgs@autox.team.net <mgs@autox.team.net>
Date: Thursday, November 26, 1998 5:34 PM
Subject: Re: SU's vs Webers when converting a rubbernose


>Hey Mike,
> I wasn't flaming you, just getting the point about SU's
> The HIF is a good carb, and I don't have a good excuse to get rid of
>mine.
> HS's have their share of problems, but in good condition, they ain't bad
>either.
> I've got a set of HS2's on the Midget, and after a bit of needle
>juggling initially (the engine has been "slightly" hotted up so the
>original needles didn't make it), I've had very little problems out of
>them.
> I've also got several customers who run DGV's, and carb problems is not
>one of the things they complain about.
> Like you, I've no ax to grind either.
>
>All the dyno tests I've ever seen quantify what you've experienced "seat
>of the pants". The DCOE does give some small HP gain on the top end, but
>was even with SU's in the mid range, and in fact, one showed that the
>HIF6 on a 1320 A-series actually gained more HP in the mid range than it
>gave up on top end, versus the DCOE.
>I've never seen a side by side test of the DGV vs SU, but my gut feeling
>is the DGV would not seem so impressive.
>
>I agree, a race car is the ideal place for the DCOE. HP is the name of
>the game, especially as we tend to run at the upper end of the tach.
>
>Rick Morrison
>72 MGBGT
>74 Midget
> 
>On Wed, 25 Nov 1998 21:39:09 -0800 "Mike Gigante" <mikeg@vicnet.net.au>
>writes:
>>The HIF is an excellent carb, and a significant technical advance on 
>>the
>>older style SU. For all around use (road) I'd be more than happy using
>>a HIF. In fact I have used a HIF6 on a 1380cc spridget and was 
>>extremely
>>happy with it. On that car I have used both Weber and HIF6 and with
>>good manifolds, the performance difference was slightly in favour of
>>the Weber at peak HP, but little or no difference elsewhere.
>>
>>Note that this is a different story than twin SUs of the older kind.
>>
>>Hey, remember - I have road-going cars with all three types - twin 
>>SUs, 
>>single HIF6 and Weber. I don't have any axe to grind, I am not a 
>>zealot. 
>>I just report my experience. In addition I have a racecar with a 
>>Weber.
>> 
>>Mike
>>
>>
>>-----Original Message-----
>>From: Rick Morrison <gofastmg@juno.com>
>>To: stritle@epix.net <stritle@epix.net>
>>Cc: mgs@autox.team.net <mgs@autox.team.net>
>>Date: Tuesday, November 24, 1998 8:26 PM
>>Subject: Re: SU's vs Webers when converting a rubbernose
>>
>>
>>>Sound's EXACTLY like my HIF's.
>>>The only advantage I can see for the Weber's is that you don't have 
>>to
>>>add oil periodically.
>>> This is worth $300????  :>)
>>>
>>>Rick Morrison
>>>72 MGBGT
>>>74 Midget
>>>
>>>On Tue, 24 Nov 1998 17:37:30 -0500 Steven Tritle <stritle@epix.net>
>>>writes:
>>>>Sounds more like SU's than Webers.
>>>>
>>>>Steve
>>>>52 TD
>>>>Mike Gigante wrote:
>>>>
>>>>> Webers just sound so much better :-)
>>>>>
>>>>> In addition, unlike SUs, they are "set and forget" - they don't 
>>>>drift out
>>>>> of tune, and they are less prone to wear problems. If they are set 
>>
>>>>up
>>>>> correctly, they are wonderful.
>>>>>
>>>>> Mike
>>>>>
>>>>> -----Original Message-----
>>>>> From: Neil Cotty <neilc@tradesrv.com.au>
>>>>> To: MG Mailing List (E-mail) <mgs@autox.team.net>
>>>>> Date: Monday, November 23, 1998 10:01 PM
>>>>> Subject: SU's vs Webers when converting a rubbernose
>>>>>
>>>>> >Hi all,
>>>>> >
>>>>> >I've read quite a bit lately on SU's, Webers etc and I'm not sure 
>>
>>>>why there
>>>>> >are so many people out there with rubbernose cars converting to a 
>>
>>>>Weber
>>>>> when
>>>>> >they could convert to SU's. As far as I'm aware a single Weber 
>>>>*may* have
>>>>> an
>>>>> >advantage at very high RPM's (3-5 bhp according to the Special 
>>>>Tuning
>>>>> manual
>>>>> >with other mods) but SU's have the advantage lower down, 
>>producing 
>>>>more
>>>>> >torque - at least thats what I hear from many racers and the 
>>books 
>>>>I've
>>>>> >read - but essentially overall performance is similar - power 
>>band 
>>>>is
>>>>> >different. If you own a single carbed B why not replace them with 
>>
>>>>dual SU's
>>>>> >instead of a single Weber? They leave more space in the engine 
>>bay 
>>>>thanks
>>>>> to
>>>>> >the smaller intake, and are more 'original' than webers. They 
>>also 
>>>>look
>>>>> >quite pleasant! I'm not bagging Webers (I'd love a pair of 
>>>>sidedraft DCOE's
>>>>> >and a xflow head!) I'm just genuinely wondering why Webers are 
>>>>chosen
>>>>> before
>>>>> >SU's. Is it a supply issue or one of 'perception', as Webers are 
>>>>really
>>>>> seen
>>>>> >as performance carburettors..
>>>>> >
>>>>> >I'd like to hear some comments on this rubbernose issue. The 
>>Weber 
>>>>route is
>>>>> >chosen far more often than the SU when changing from single carbs 
>>
>>>>to
>>>>> >increase performance (*without* other engine mods!! not talking 
>>>>about head
>>>>> >work, headers etc) - I'd think you'd get similar performance by 
>>>>going to
>>>>> >dual HS4 SU's on a std car. I've never experienced a late model 
>>>>rubbernose
>>>>> >so I can't appreciate how 'impaired' they actually are. My GT is 
>>no
>>>>> >bahnstormer even as std with 94hp, in good nick with dual carbs, 
>>a 
>>>>lot more
>>>>> >has to be done to improve it's performance! Heck even my A eats 
>>it 
>>>>for
>>>>> >breakfast! <G> Yes, it really does.
>>>>> >
>>>>> >Cheers,
>>>>> >Neil.
>>>>> >--
>>>>> >Neil Cotty - Sydney, Australia
>>>>> >1970 MG B GT / 1959 MG A 1600 Mk1
>>>>> >
>>>>
>>>>
>>>>
>>>>
>>>
>>
>>
>
>___________________________________________________________________
>You don't need to buy Internet access to use free Internet e-mail.
>Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
>or call Juno at (800) 654-JUNO [654-5866]
>


<Prev in Thread] Current Thread [Next in Thread>