ratm

Hi Folks,

We all know there are clearance issues with the FD inlet manifold and the firewall with REW conversions, also that some of the lines that run along the firewall sometimes have to be moved around too (I think they are the air con or heater hard lines, Im not sure as the car is not here).

Im using a Cosmo 13BRE inlet manifold and plenum/upper inlet on my REW swap.

I know that the firewall has to be massaged a bit with a hammer so that the manifold clears for the RE and REW inlet manifolds to clear.

What mods did you guys do to the lower inlet manifold so that it clears the firewall ?

What mods did you do to the firewall ?

Hopefully if anyone who has used the Cosmo RE manifold can respond too that would be great.

I have searched but cant find any specifics on what people have done to their firewalls to clear their manifolds, also what lines etc that run on the firewall had to be moved or modded either and was hoping to create a thread for future reference for other people who are doing the conversion.

Thanks.

RMD

I'm almost ready to post my build thread that covers what I did.
Assuming you are talking about bolting to an rx8 trans:
My setup uses the cxracing LIM which is centered on the engine block, much like the *xsessive * or other aftermarket LIMs. Mine clears just barely even with it sitting a few more inches forward than the factory REW LIM. To fit a factory Lim that swoops towards the rear of the engine would require fire wall cutting for it and the UIM to clear.

With my LIM in place, the UIM (REW) needed only slight trimming on the back corner to fully clear the fire wall and lines. The AC line was completely fine and I only had to unbolt and push the heater core tube section down a bit.

​​​​​​​If the RE UIM is significantly wider than the REW's, I would bet that it would hit the fire wall even with a center oriented LIM.

ratm

Thanks for the detailed reply.

I have seen both of those lim's, I didnt get either because of the cost, (Im in Australia and the exchange rate isnt the best, postage is really expensive too) the RE has much larger runners so I cant really use either of them anyway.

I have seen people using the RE manifold on REW conversions, my engine builder says that it is oriented a bit more forward than the FD one (the lim) but he says that the lim is touching the firewall now and he has to remove it and get in there with a hammer.

Thanks for the info on the hard lines, greatly appreciated.

I would be interested to see your build thread too, Ill be posting one also once I get the car back.

RMD

Yes, the price of those manifolds are a bit rediculous. Mine came with my full swap kit and it was all on sale so it was significantly cheaper for me when I bought it.

​​​​The only firewall adjusting I needed was for the CXRacing secondary fuel rail that comes with the LIM. Had to pound a small area where the back of the rail was touching the fire wall, was not a big deal.

I wonder once you fit the RE LIM in place, if the RE UIM will be hitting still. I know that some people have used FD transmissions and a different engine mounting position to gain some forward placement, allowing the manifolds to clear. It's like no matter which way you turn on these swaps, there is always a compromise.

ratm

In the few pics I have seen online where people have used the RE UIM they seem to all have the grey firewall insulation removed, possibly for clearance.

Im using an FD transmission but with the JDM RX8 5 speed bellhousing and rear extension housing so that it bolts into the factory location.

See how we go, I told my mate if he needed to rework the firewall with a hammer to go for it.

RMD

Here is an incomplete pic of my setup, I also removed the insulation to help make room.