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swap
Posted: Sat Feb 14, 2004 8:22 pm
by les
I'd like to swap an 1 1/2 HIF38 carb for an 1 3/4 HIF44, anyone?
Posted: Sun Feb 15, 2004 1:19 pm
by Peetee
I have an earlier HS4 (the same size) if your interested?
Posted: Sun Feb 15, 2004 1:48 pm
by MrA.Series
I thought all HS4s were 1 1/2?
Posted: Sun Feb 15, 2004 1:49 pm
by Cam
They are.
Posted: Sun Feb 15, 2004 1:51 pm
by MrA.Series
So why would les want to swap his 1 1/2 HIF38 for an older 1 1/2 HS4 with Peetee?
I though les wanted a 1 3/4 carb, like a HIF44?
Posted: Sun Feb 15, 2004 2:01 pm
by Cam
I don't think he would. But Pete might wonder if Les would either want a HS4 or maybe there was a bit of confusion in the air!!
Why don't you ask them anyway?

Posted: Sun Feb 15, 2004 2:05 pm
by MrA.Series
Oh, just 'cos we're the only ones online at the mo! You're good at answering Q's
I just got a bit confused.
I think Peetee might have thought that les wanted a 1 1/2 in exchange for a 1 3/4 that he already owned. Well, that's my theory!

Posted: Sun Feb 15, 2004 2:08 pm
by Cam
Oh, just 'cos we're the only ones online at the mo! You're good at answering Q's
I think Peetee might have thought that les wanted a 1 1/2 in exchange for a 1 3/4 that he already owned.
Could well be! I suppose we'll find out when they get on-line and shout at us for hijacking the thread (again!!

)
Posted: Sun Feb 15, 2004 2:11 pm
by MrA.Series
Not really hijacking it, as we're not (for once!) going off topic. Kinda helping to make the topic clearer. How very public spirited of us!
Posted: Sun Feb 15, 2004 7:04 pm
by Peetee
I'm hoping he has a 1 3/4 and wants a 1 1/2. It wasn't clear either way.
Posted: Sun Feb 15, 2004 7:53 pm
by les
Just got on line, With respect I think it is clear. Swap 1 1/2 FOR 1 3/4, ie; I've got the 1 1/2!
Posted: Sun Feb 15, 2004 10:00 pm
by Peetee
Time for me to back out quietly then

Posted: Sun Feb 15, 2004 10:16 pm
by les
No harm done, come back! Preferably with an 1 3/4 carb!
Posted: Mon Feb 16, 2004 9:37 am
by MrA.Series
les wrote:With respect I think it is clear. Swap 1 1/2 FOR 1 3/4, ie; I've got the 1 1/2!
Yeah, thats what I though you said you meant

Posted: Mon Feb 16, 2004 12:59 pm
by Peetee
Before anyone else chips in I'd just like to say I'm not having a good week at work either

Posted: Mon Feb 16, 2004 3:52 pm
by Kevin
Les why do you need the 1 3/4" I assume its for a 1275cc engine, because thats what I thought I would need for my midget engine and I was reliably informed that an 1 1/2" is more than up to the job unless you are going for a tuned specification and really only comes into play above 60-70mph is this what you are trying to achieve ?
Posted: Mon Feb 16, 2004 9:08 pm
by les
15 posts and still no carburettor!
Posted: Mon Feb 16, 2004 9:12 pm
by les
Kevin, I am under the impression that the 1275 Ital engine is fitted with an 1 3/4, and just wanted the correct carb. Perhaps I'm wrong, will check further.
Posted: Mon Feb 16, 2004 10:10 pm
by Cam
The Ital engine is fitted with a 1 3/4" carb, but the Marina (basically the same engine) was fitted with a 1 1/2". The 1 1/2" is perfectly adequate (in fact I used to use one on my 1293cc 85ish BHP Mini). It's just that later cars had bigger carbs fitted (Maybe it was the trend or something to do with emission control?).
Apparently the Marina / Ital engine produces around 60-61 BHP, so using Vizard's rule of thumb of 2 - 2.2 CFM for each HP produced, that gives 61 x 2.2 = 134 CFM needed for unrestricted power output.
The SU HS4 flows approximately 142 CFM and the HIF44 flows about 240 CFM, so it can be seen that the HS4 should be up to the job of supplying a standard Ital engine. Having said that it was fine on my 1293 also. It was more than likely starting to choke the engine at the top end but I doubt I lost more than a couple of BHP though it.
Posted: Thu Feb 19, 2004 3:59 pm
by Kevin