SU carb queries

[Sealik]

Just got a set of 46mm SUs mounted on a Lynz D1600 manifold, originally from Australia I believe.

After looking at it....I've came to the conclusion that is suited for a engine that sits more upright.

 

Roadster?

 

 

 

 

As compared to the K14 manifold in foreground...angle of SUs to engine.

Add another 8-10 degrees to the SUs/manifolds, to mount to the L20 engine..... relative to how they are sitting now.

 

Too much lean for SUs to function properly?????

Looks like the float bowl/chamber has been pivoted to compensate for lean, the float bowl on my other SUs is sitting at the same angle as the dome/piston chamber

 

 

 

Intake runners are a lot smaller than the K14...would be a whack of grinding to enlarge it for an L20 engine

 

 

Looks like it had 42s (+) on the mani at one time, that is a 46mm insulator...same size as SUs

 

 

Thoughts???

[wayno]

I think the bowls have to be level, as you can see from my SU package here, the domes are tilted quite a bit.

These are tilted a lot in my formar L320 A block truck.

[ggzilla]

Wayneo is right-o. The carbs are supposed to tilt. The fuel bowls should be more or less level.

 

The Lynx D1600 is specifically for the L16, which is a slant four.

[Sealik]

These are tilted a lot in my formar L320 A block truck.

 

Looks like your SUs are tilted the same as my SUs...relative to the manifolds that is.

Also looks like your engine is sitting up right (?), whereas my engine will be leaning about 11 degrees, resulting in a more 'severe' angle on my SUs.

 

Wayneo is right-o. The carbs are supposed to tilt. The fuel bowls should be more or less level.

 

The Lynx D1600 is specifically for the L16, which is a slant four.

 

 

Yeah....I figured the bowls should be somewhat level... :D

I noticed the intake flange casting has been machined down to the same width as an L exhaust mani, which makes me wonder if it was actually from an L engine.

Difference between L and Roadster manifolds?

 

Bottom right in pic.

 

[merlin]

You can go compare it withbthe roadster front clip next to my barn... Roadster 1600 mani is still on that crapped out r16

[Sealik]

You can go compare it withbthe roadster front clip next to my barn... Roadster 1600 mani is still on that crapped out r16

 

Different bolt pattern between the L and Roadster...Foxyroadster says so :D

[wayno]

I never noticed that before, the U20 intake bolt pattern looks like the L block pattern, but they are not the same, the U20 intake is slightly longer, maybe half an inch wider between the upper intake mount bolts. The R16 is a differant pattern altogether.

[Sealik]

Who would of thunk.. :D ..Lynx manifold....in another thread.

 

Thanks Fisch!

 

 

http://community.ratsun.net/topic/28984-sus-setups/page__st__40__p__433442__hl__lynx__fromsearch__1#entry433442

 

http://www.ebay.com/itm/DATSUN-1600-510-620-STANZA-BLUEBIRD-TWIN-SU-MANIFOLD-/330362793211?pt=AU_Car_Parts_Accessories&hash=item4ceb282cfb

[Sealik]

Was wondering how the float bowls 'pivoted'....actually they don't.

 

There is a rubber grommet with a notch in it, and a corresponding one (tab) cast into the side of the SU

As seen where screwdriver is pointing, these are positioned to have fuel bowl upright, same angle as 'round top'

 

 

IF you flip them, from 1 SU to another.....you get the float bowl to sit slightly askew to round top, for different applications, as in the Lynx mani

 

 

Also rotated the top of the float bowl so the float pivots from the engine side, as noticed in all SU pics I've seen

 

Will now sit level on the L6 mani