Throttle body swaps for 87 si

[mrlindeman]

I know that fabbing some kind of adapter plate would be nessisary, but i was wanting to know which of the larger d series throttle bodies will work on the 87 si? Im concerned about the throttle links and the vacuum hoses as well. that oem throttle body is puny. Ive heard that the 85 prelude TB will work but im having a very hard time finding any info on this. Thanks in advance.

[lxndr]

Do you have a cold air intake, header, low back pressure exhaust, adjustable fuel pressure regulator, more agressive cam and an adjustable cam gear?

If not, this swap will be pointless. Adding a larger throttle body will only allow the potential for more air flow into the engine, but if the air is restricted on it's way out, a larger throttle body will do nothing for performance. Actually it will probably make your car run lean which can actually hurt performance and is why you would need better fuel management. Increased air flow rerquires more fuel in order to make power.

But if you want to try it a simple adapter could be made out of a 1" thick block of aluminum. If you use an '86-'89 Integra throttle body, one of the bolt holes lines up and the bore for the butterfly will end up in approximately the correct position. This will also require that you port your intake plenum to match the throttle bore.

I looked into doing this a long time ago and had fabricated some parts, but decided to scrap this idea and swap the whole Integra motor instead!

[mrlindeman]

Full exhaust, no cat. Stage 2 cam with port and polished head and intake manifold. No fuel pressure reg but a high flow ram intake i do have. Thanks for the info.