Black13B

iTrader: (1)

I've been snooping around and I can't seem to find any information.

If someone else can find me a thread, please post it, otherwise I'll just ask..

I heard somewhere that the FD3S UIM will not bolt up to an FC3S LIM.. But I'm not sure if thats for a TII or an N/A LIM..

I guess I'm asking what is the difference between the LIMs and UIMs. What is interchangeable? I've seen pictures of the FD3S UIM and it looks very close to the bolt pattern of the FC3S S4 UIM. If I had to make an assumption I would say that they do bolt up. But I am uncertain.

This is for a project of mine, but I'm not working with the stock ECU, so there is alot of things that may or maynot be a concern.

If anyone can provide information if it can bolt up to an S4 N/A LIM, or anything else that can bolt up to it that would be great.

Thanks guys.

rotarygod

iTrader: (1)

None of the other manifolds just bolt up. The T-II and 3rd gen lower manifolds are much taller than the n/a manifolds. If you tried to bolt on a new upper to an na lower, you would need a new middle section that is a few inches long to bridge the gap. When people say they used a 3rd gen upper, they mate them to T-II lower manifolds. Even then they don't just bolt up. A couple of the bolt holes have to be modified and there is a little bit of port runner matching to do. Grind here, drill there, etc.

Black13B

iTrader: (1)

Interesting..

Do you have any links or pics or something of modifying them to mate up?

rotarygod

iTrader: (1)

Look up a forum member named BlueTII. He has it on his car.

Black13B

iTrader: (1)

Bump.

So will an FD3S LIM mount to an S4 block? I would assume so, but..

What are the differences between the manifolds on the FD3S and FC3S?

rotarygod

iTrader: (1)

No. The ports on the 3rd gen engines enter from a different angle and are placed higher on the housings. The bolt pattern isn't even the same. I don't recommend any of the adapters out there. You'd have to see it to understand. Just use a T-II lower and adapt a 3rd gen upper to it.

Black13B

iTrader: (1)

Cool. Thanks for the help, rotarygod.

I've already started looking.

Black13B

iTrader: (1)

Sometimes I overlook the simple stuff..

Any other LIM will not work, as my motor is a 6-port, will it?

Whatever I mate up will likely have to be with the stock 6-port LIM, right?

rotarygod

iTrader: (1)

It is possible to physically bolt on any '86-'91 intake manifold to that engine. The T-II lowers have been modified to fit with some major port matching. You will completely lose the 6 port sleeves though. The eaiest thing to do is to use the 6 port lower, the 3rd gen upper, and build a center section that mates them up to each other. If you are still using the stock ecu, you are not going to get any mor power though. It will alter the tuning of the engine is spots but you may or may not like it. Get a computer first and then worry about the intake. You'll be much happier.

Black13B

iTrader: (1)

Thanks again for the info rotarygod.

I thought I would have to ditch the sleeves for sure if I changed the LIM (after I realized it).. Hmm.. Not sure if that's the route I want to take, but I may.. It might not be such a bad idea..

Icemark

The easiest way might be just to go buy the FD middle to LIM gasket. Then you will see if it will match up. Gaskets are cheap and provide you with the perfect templates to see what will match or what custom part might need to be made.

But something to remember the FD UIM is designed for a pressurised intake, and will have slighty different flow design than the N/A, which is optimized for the dynamic pulses.

Are you Turboing your N/A??? or???

Black13B

iTrader: (1)

Excellent idea Icemark! That's probably the best route.. I never thought of just purchasing the mating gasket..

I didn't know the FD3S UIM was designed for pressurised intake.. Maybe I will have to re-evaluate my design.

I'm not turboing the 6-port.. I prefer to stick with the sleeves so I won't lose low-end too much.. But I'm trying something a little different.. I'll be posting pics when it's all said and done.

But a big chunk of this project is that I'm relocating the intake filter to the opposite side of the way it sits in the N/A FC3S 13B.. And probably using some sort of custom TB (should it be fesable when I finally get everything in order).

While we are on the topic, let me consider some other options.

What about an FC3S TII UIM? Will that mate up without very many issues? I'll probably hit up mazda for the gasket sets for an FD3S LIM/UIM mate gasket and also one for an FC3S TII LIM/UIM mate..

But any extra info is greatly appreciated guys. I'd rather hear it from the guys who know, and possibly save myself the hassle of just buying the full manifolds and then deciding from there..

Black13B

iTrader: (1)

^

Juan

iTrader: (28)

series5 LIM are a closer match for the FD upper intake manifold and require less porting than s4s.

My friend is putting a TII LIM/UIM on his 6port engine. You have to remove the sleeves, fill 2 holes on the TII LIM with aluminum, and port match the LIM so the ports on your N/A get air. He went this route because he can use a stock turbo and manifold without using a spacer.