Throttle body spacer issues

volospian · Post by **volospian** » Mon Feb 11, 2013 10:21 am

Hi,

What would b the errect of putting a spacer btween the throttle body and the intake manifold on an LS engine?

I've got myself an LS6 manifold (complete with TB, rails and injectors:)) to go on my L33 engine, but the truck water pump has a vertical top inlet pipe while the car engine has a horizontal one, and so the TB snags on the side of the existing inlet pipe. I reckon a spacer of maybe an inch or so will allow me to use the existing pump and not have to swap to the car unit, hopefully saving me some cash.

I'm just wondering what effect, if any, such a spacer would have? My assumption is none whatsoever, but I thought I'd check....

kiwicar · Post by **kiwicar** » Mon Feb 11, 2013 11:08 am

Hi
Unless you have the car on a dyno when you add the spacer then I sincerly doubt you would be able to know you had added it, even then probably only by printing out both power curves onto tracing paper and putting one on top of the other actually even then I think the differences would be swamped by change in gearbox oil temperature. . . If you were talking more than 4 inches long then maybe you would notice a "flat spot" move or it pull away a little more easily from less than 2000 revs, even then I think it would take a 6 to 8 inch spacer to make any difference what so ever.
Best regards
Mike

volospian · Post by **volospian** » Mon Feb 11, 2013 12:00 pm

Good, that's what I was thinking...

Cobratone · Post by **Cobratone** » Mon Feb 11, 2013 3:05 pm

What about filter to bonnet height with a spacer??

volospian · Post by **volospian** » Mon Feb 11, 2013 3:30 pm

Hmmmm.... I won't know until I have the engine fitted, but if it won't fit with a 1" spacer, then it won't fit with the vertical inlet either and I'd then have to buy a car water pump anyway...

Cobratone · Post by **Cobratone** » Tue Feb 12, 2013 11:12 am

I'm struggling for filter space on my AK, you've seen the throttle body pictures

volospian · Post by **volospian** » Tue Feb 12, 2013 11:55 am

Ah, I see what you're getting at!

Your TB's all point up though, mine is a single TB pointing forward, so the engine looks more like the pic below (linked from british american engines). The spacer will need to sit between the black inlet manifold and the silver TB (above the water pump pulley). This will shove the whole TB forward so that the throttle mechanism clears the pipe.

If you look at the top water inlet pipe, it sticks straight out on this engine (an LS6) and causes no issues, but on my engine (L33) it comes out of the top of the pump. You can just see a small, flat, round casting beside the TB where the truck pipe would come out. It goes straight up for about half an inch, then angles maybe 30 degrees forward and a similar angle away from the TB, coming almost as high as the TB. Because of this angular direction, it's only the bottom inch or so that is an issue, and I reckon if the TB were an extra inch further out, it would clear the bottom of the pipe and leave enough room to fit nicely.

The LS6 intake on an L33 engine is fairly common in the US and the standard option is to just swap to a car spec pump, but then there are plenty of car pumps around and so they're cheap to pick up. Not so common over here. I could still pick on up relatively cheap from the US, but shipping it over would add cost and it would end up being a couple of hundred quid, while my next door neighbour will knock me up a spacer for a couple of beers.

The TB will then point towards the front of the engine bay, so providing I use an angled feed pipe, I should be able to find plenty of room for the filter.

Cobratone · Post by **Cobratone** » Tue Feb 12, 2013 10:45 pm

I must admit that my first thought was that you had a front facing throttle body but when I re-read your post you mention tb's (plural) so made the assumption you had gone for stacks like mine, sorry, my mistake. Can't help you now

volospian · Post by **volospian** » Wed Feb 13, 2013 8:22 am

Ah, yes I did! Sorry, my mistake. Obviously my hands were engaged but my brain was not in gear...

stevieturbo · Post by **stevieturbo** » Wed Feb 13, 2013 11:10 am

It'll be fine.

Or you could just buy a different water pump.

$2-300 should get you one. Or you can find "new" take offs on egay for much less. Plus postage etc from the US.

LS3 or LS2 style is what you'd want.

L33 pump is weird !

LS3 style below

http://www.ebay.com/itm/LS3-LSA-L76-LS7 ... tr&afsrc=1

http://www.nookandtranny.com/mm5/mercha ... gory_Code=

Or LS2 pump ( I bought one from SDPC for $215 a while back )

http://www.nookandtranny.com/mm5/mercha ... gory_Code=

volospian · Post by **volospian** » Wed Feb 13, 2013 11:25 am

Yeah, like I said, I'd rather not pay the price for a new pump. I also think that some pumps won't line up properly with the L33 crank pulley as they have different FEAD setups. I believe the LS1 pump works without modification, but not sure about the others. I have read a few threads about people having to change the crank pully or buy (or make) a set of spacers to line the pump up with the pulley...

All sounds a bit of a PITA if a simple spacer betweent the TB and intake will fix the issue.

stevieturbo · Post by **stevieturbo** » Wed Feb 13, 2013 11:54 am

yes, a spacer will be fine.

Eliot · Post by **Eliot** » Wed Feb 13, 2013 12:46 pm

ditto - cant see a problem with a spacer either.
Use either ally, nylatron(nylon) or Tuffnol Carp. Probably something ralph could make easily.