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Don_R

Don_R

Jedi Warrior
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Hi all,

Was thinking of upgrading to dual SU carebs on my 73 Spit 1500 and was wondering if it is better to go with HS2 or HS4 carbs

Stock motor so far. planning to upgrade the cam to a road cam for a little more performance. Also, the motor looks like its a 1300. FK29596 UE is the ID of the motor, not FH.

My thought was to go with HS2 carbs. trading air velocity for air volume.


Don R
 
Good question. I would think you'd be better off with the 2's with a stock engine. But the cam might "open up" the breathing capabilities enough for the 4's. Either way, you'll probably want to experiment with the needles and their settings.

Headers, too?

Sounds like you're right on the cusp between them...
 
It hust so happens that Pacesetter header and monza exhaust are in mind.

So happens my mistress works for an aftermarket parts wholesaler and can get my her employee price on the exhaust.

Don
73 spitfire 1500
 
Don_R said:
It hust so happens that Pacesetter header and monza exhaust are in mind.

So happens my mistress works for an aftermarket parts wholesaler and can get my her employee price on the exhaust.

Don
73 spitfire 1500
Click to expand...

Cool! Where does your wife work? :devilgrin:

Looking forward to hearing which carb you choose.
 
My MISTRESS works at Keystone Automotive. She is a product person, handles the part selections for the catalogs and sale flyers.

Its fun taking her to our local hill climb and hear talk part numbers with the racers. Its funny to see the look on their faces when a 5'2 blonde can look at an an engine and call out the the equipment and part numbers from memory.
 
Lucky guy! Janet couldn't care less about such playthings. She is supportive of my addiction, but is content with a book in the shade when we go to shows.

Back to the carbs, though, here's a good write-up that may help.

Mickey
 
I'd be for the HS4's as well. The 2's would be a bit restrictive IMO.
 
The euro 1500 came with dual HS4s so it seems the logical choice. The only problem is that the manifold is hard to find in the US while the HS2 manifolds are pretty easy to find. I have a set of each but haven't been able to find a manifold for the HS4s so am in the process of getting the HS2s ready to install, replacing my Weber DGV.
 
Fuelie Spit is a more distant project. While sittin in Afghanistan I was having bizzare dreams of a multi-point injected turbo spit. Must have been the desert heat.
 
:lol:

I had similar dreams of BDA twincams in a more "tropical" environ thirty some years back. :wink:
 
Hi All,

Well the decision has been made.

Got a deal on a set of HS4 and intake.
Having grown up with a TR3 in the family I had a thing for twin carbs,
and as cool as the weber setup is it was more expensive.

Now the wait while Jeff rebuilds my Dizzy.
And its gonna be 60 on Sunday.


Don R
 
Did that last year, dual HS4's.

Boy, did it help. My 1977 1500 Spit just runs better than ever. There is more oomph. Power in the corners. That sound.

The European carbs I used had to be rebuilt. However, the car just runs well with the European stock needles. Rebuilding the SU's was easy and greatly improved our knowledge of these carbs. Best $400 i ever spent on the car.

I used a 74 Midget exhaust manifold and stock 74 exhaust.

Larry
 
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