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SDS Throttle Body interference

TASEsq

TASEsq

Well Known Member
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We got to the point of test fitting the SDS throttle body to a new engine build. This is a -C1E6 but with an -A1B6 sump on it (forward induction). It all looks like it fits ok, but the MAP hose barb fittings interfere with the sump casting.

Is anyone aware of any 90 degree barb fittings?

Otherwise I’m looking at either a 1/2” spacer (and this means changing the studs on the sump 😬), or rotating the whole thing so the throttle arm is down. I need to work out if this is feasible or not from a throttle cable perspective.
 

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They look like straight threads, not NPT. If that is the case, 90’s won’t work. Ask ross about the thread size and see if you can get banjo fittings in that size.
 
lr172 said:
They look like straight threads, not NPT. If that is the case, 90’s won’t work. Ask ross about the thread size and see if you can get banjo fittings in that size.
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Could also cut down the fitting by 1/3 or 1/2 length. Looks like that would allow a hose to fit fine. That would take off the barb, so would need a hose clamp. I have also seen rubber tube elbows, though not sure where to source them and would need to use rubber hose so you could fuse it. The are common on auto vacuum lines.
 
Photo snip from latest EM-6 installation manual makes me suspect the manifold pressure fittings can be relocated to a different face of the throttle body.

Ref more photos at Post #12.
 

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Just had a look at the engine, and throttle arm on the bottom is going to be difficult - I would need to swap the throttle cable to the left side of the engine and this sump has no provisions to mount anything on that side. The only boss is on the right side of the sump - but this makes the throttle arm work backwards.

I’m thinking I need a 3/16 (4.5mm) plate. This would mean I don’t have to change the sump studs and the MAP hose just fits.
 

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They are definitely straight threads. There is an o-ring. 10-32 looks on the money to me.
 

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johnbright said:
Photo snip from latest EM-6 installation manual makes me suspect the manifold pressure fittings can be relocated to a different face of the throttle body.
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Thanks. Mine looks different to that. I can’t see any other provisions.
 

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That will not likely work. Throttle plate doesn't close fully. typically the Vac ports are on the raised side. If you use the low side, the ports will likkely get too close to the opening between plate and wall, you will get eroneous readings. You want the ports as far from the plate as possible to get accurate vac indications.
 
TASEsq said:
I would need to swap the throttle cable to the left side of the engine and this sump has no provisions to mount anything on that side. The only boss is on the right side of the sump - but this makes the throttle arm work backwards.
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I have a different sump, but I was able to make the throttle control cross over and work the arm. It required an extension and an adapter plate but it's working really well.
 

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While I prefer the pressure tap to be in a common plenum, one can always go back to the intake port location that has served just fine for, well, EVER.
 
Thanks all. Heaps of good options.

These are an option - but Ross reckons expensive and you have to buy them in bags of 50!!

EA-LB50 | Pneu-Edge barb fittings, adjustable elbow, 3/16" barb, 10-32 UNF

IMI Norgren
www.norgren.com

I think the next easiest option might be a spacer - if I can find one that’s 3/16 thick I will get away with not changing the studs in the sump (the potential of something going wrong there scares me!)

I’m thinking of getting something lasercut out of 5mm plate.

I’ve asked Ross about moving the MAP ports.
 
TASEsq said:
They are definitely straight threads. There is an o-ring. 10-32 looks on the money to me.
Click to expand...
The threads are 10-32 Per Ross several years ago. Before I would go messing around and modifying the throttle body by drilling holes, I;d be talking directly with Ross.
 
Thanks for the good advice all! A 5mm plate solved the problem, and by using a thin washer and a star washer we didn’t have to change the studs in the sump.

Worked out well. Best part is it was free - found the stock laying on the floor of my dads shed 😬
 

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Nice work.
I'm curious, what are your plans for an airfilter system and bringing air to the throttle body?

Thanks
Brad
 
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