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Posted: 29 Nov 2007, 22:47
by jason k
why fanny around when you can fit a set of dells or weber dual twin chokes on, get more power and more mpg for not a lot of money. :wink:

Posted: 30 Nov 2007, 08:05
by Dubstar
Er, cos SU's are dirt cheap and a set of Webbers with manifolds usually cost £300+. Unless you've got a set for, say, £50, including post?
Oh, and I've got a set of SU's :wink:

Posted: 30 Nov 2007, 21:44
by ..lee..
what su`s you got dubstar. the hif`s need to be mounted at the correct angle as the float chamber is incorporated in the carb body. the older su`s with the external float chambers can be mounted at an angle if you set the float chamber level.

only problem i see is that the su`s would need a complicated linkage as they are normally mounted next to each other and close together.

go for it and let me know how you get on.

lee.

.

Posted: 30 Nov 2007, 22:30
by PC52
I fitted SU carbs on 2l bays and a FugitiveII rail, (Fugitive used to destroy van gearboxes reguarly) Fugitive had V8 Range Rover SU carbs, it was greedy on fuel but quick as
Just make sure the oil pots are alright, I started with 20/50 and then used atf.
No fuel dumping, took a day of fiddling to set them up.
K & N filter - help to stop the slides freeze up. Motorcycle (Bonneville) 2 into 1 cable fitting.

Posted: 30 Nov 2007, 23:34
by Simon Baxter
Westy.Club.Joker wrote:S.U.- Sodding Useless :(

What he said.

Posted: 01 Dec 2007, 08:48
by jason k
Dubstar wrote:Er, cos SU's are dirt cheap and a set of Webbers with manifolds usually cost £300+. Unless you've got a set for, say, £50, including post?
Oh, and I've got a set of SU's :wink:

i see but you still have to make two inlet manifolds and design and fabricate a linkage.
surely by this time your up to dell money without the power??
i bought my dells for £100 , manifolds for £70 a pair and a linkage for £70. is it really worth messing with su s ?? imho the answer is no. :wink:

Posted: 01 Dec 2007, 11:14
by Dubstar
The ones I have are off a TR7, so I think they're HS4's. Like I say, it was more just to see if it could be a viable alternative to the Solex carbs, that seem, to me anyway, rubbish, overly complicated and have real problems with the spindles leaking air. I'm not saying SU's are brilliant, but if they were good enough for an Austin Ambassador then they're good enough for me. I mean, Dellortos and Webbers, what did they go on? Ferraris -ptuh! :wink:
Also from a fuel consumption point of view with their variable venturis and all that. And I have the David Vizard how to modify A series engines book with several chapters on how to modify SU's.
Again, unlikely that I'll do it, but you never know. As for the manifold, I thought just a piece of rightish angled pipe with a flange on either end and bolt one end of it to the existing manifold with the carb on the other end.

Posted: 01 Dec 2007, 12:52
by wasserleaker
not dead relevant to this :) , but, i fitted an SU from a mini to my suzuki SJ offroader a few years back when the std (mikuni i think) packed up after gulping some water in, made an ally adaptor plate, worked brilliantly and loads simpler and less troublesome than the std carb which i never managed to get set up quite right. did the same type of thing for a friends SJ as well but with a carb from a metro (were they strombergs or SU's?) that worked great too.

Posted: 01 Dec 2007, 18:09
by ..lee..
with webbers and dell`s if you get a lean spot you can only go up a jet size or mess with air correction with a su you can actually fine tune them to richen up only at that point.

when run on a healthy pinto they lost nearly 20 bhp to webbers but gained 30 lbs/ft of torque and that was proven not just guesswork.

a lot of work to get right but they DO have potential

Posted: 01 Dec 2007, 19:26
by wasserleaker
a mate in the motor trade used to swear by a tuning firm in alfreton, derbys run by a chap called pete burgess who could fine tune SU needles to correct fueling flat spots at certain parts of the rev range, obviously a massively knowledgable bloke who could back up the theory with real results, he did a fair bit of work on historic race and hill climb stuff, i think MG's were his particular perversion.