throttle body spacer?

[jimustanguitar]

Is the throttle body on the Reatta specific to that model, or would an aftermarket throttle body spacer for any 3800 in that year range bolt up with no problems? I don't know many of the differences in the GM engines from that era, are there any other very specific engine parts, or do most of the obvious ones bolt on correctly? Does anybody make an interchange manual that covers Reatta parts? Thanks for any help that you can offer.

[Guest Greg Ross]

What is the object of the exercise here, the TB is I believe the same for the 3.8L 87-90 years of service. 91 and later for the 3800 Series I the bore is much larger.

And not aware of any Reatta specific parts on the power pack, E-Body (Riv,Trofeo, etc) would have shared everything including the front sub-frame.

[Guest EDBS0]

You had better seal it really well or you are going to get antifreeze in the oil

[padgett]

a: yes

b: the "C" throttle bore necks to about 1 3/4", the "L" bore is more like 2" (the difference AFAIR is a bit over 30%. Keep in mind that the entire intake of the "C" engine is pretty restrictive and the neck at the radiator brace is no bigger than the TB. And then there is the cam.

Now I know the early TB does not fit on the snakes intake and the snakes intake has some different passages than the "C" heads so that won't just bolt up either.

You can obtain a complete "L" engine and bolt it in which would get you a slightly hotter cam as well.

If I had a few months to spare the L-67/Reatta transplant could be worked out - some things just have to be tried - but I don't and the two people I sent a CD with all of the prom information have never been heard from again.

So it comes under the heading of "could be but would requre someone with deep pockets to do the first". I have a lot of information from BB but a stick car has different issues from an automatic.

For me, 165 hp is "enough" - am more concerned with MPG on 87 PON than HP - so I lack the burning desire to experiment on mine. But is certainly doable.

[jimustanguitar]

You asked the object of this excercize... My plan is to mount an oriface nozzle in the tb spacer so that I can add a water/alcohol injection system to cool the combustion chamber and improve the efficiency of the engine slightly. I want to add this to the tb spacer so that I don't cause any problems with the electronics upline of the tb, like the maf sensor, and I wouldn't want to erode the throttle butterfly or damage its mating surface at all either. so I have concluded that adding the injection system via a tb spacer would be ideal. Don't think that by alcohol injection, I am attempting anything like nitrous that would cheapen the car (this type of injection is nothing like that at all, it's purpose is cooling, not combustion), I'm just trying out a vintage hotrod tweak, like teaching a new dog, old tricks.

[2seater]

Just for info. purposes, I am running an alcohol injection system that injects ahead of the MAF. It has about a 30 deg. cone spray and is directed against the screen but biased to the side away from the actual sensor passage. So far no issues. It is set to turn on @ 3.5 lbs. of boost. I am not sure what other benefit it would have if the system is otherwise stock. It would probably enable you to use more timing with 87 octane, or maybe more compression ratio, but you will use a lot of alcohol.

[2seater]

There really shouldn't be any issues with antifreeze in the oil as the passage in the throttle body is sealed from the intake tract, however, the steel tubes for the throttle body heating will not fit if the throttle body is relocated. A spacer between the MAF and the throttle body will work (I have one for different reasons), but there are a lot of things in the way to get any additional plumbing into the spacer.