Okay so I have search and tried so many different ways to put it in google or rx7club.com to find out what are the modication to put in a s4 engine into a s5 chassis. I keep getting alot of s5 blocks in s4 but not other way. Reason being I can get a clean rebuilt s4NA engine for cheap that I can use and I dont see to many na s5 swaps out there.

I mean I will still attempt it but if it will cost me more money then just getting a full turboII S5 swap I will just do that but also dont feel like ordering a $1500 swap online and not knowing the exact conditions. Any help would be great.

 

You'll have to grind the rear iron in order for the S5 intake manifold to fit. You also have to block of the EGR port on the top of the center iron.

Run no emissions rack (keep BAC, thermowax/fast idle cam, & probably the throttle delay dash pot though.), it'll make life much easier.

You'll need to figure a way to trick the ECU into thinking the S5 OMP is working. Not sure if it'd work but I'd bet you could put the S5 front cover/ electric OMP on the S4 keg.

This may help you-

http://www.rotaryresurrection.com/2ndgen/techmenu.html

MY daily is an S4 with an S5 keg, so I can probably help you quite a bit.

 

Okay well here is my deal, I can either get a reman s4 short block and i am going to go na-t or i can get a s4 turbo swap for a good deal. So alot of the stuff is going to be different such as intake manifold and etc. Buy I guess main thing is the OMP that will be change since I guess I will have to go with all s5 sensor? no?

 

I like the na-t, tho most people dont. To each there own. Your biggest issue with either of these swaps is not what bolts go where or which bolt holes do i need to modify to .... etc etc. The s4 keg and the s5 keg will bolt to the frame the same and the trans the same. they both are the same size. none of that will be different. If your going to use all series x components on your series x engine, then you have no worries. Your issue is control. What are you going to do for the ecu for either the turbo II swap or the na-t. That will dictate which sensors you need to run and etc etc etc. I agree with landon about eliminating the emissions nonsense. The rest of whats needed depends on which keg you choose. keep in mind you'll need a new counter weight either way.... s4 counter weights are diff than s5, cuz the rotors are diff weight

Keep asking question and weighing options tho... we're here to help

 

Please make a build thread too so others can also know how to do the swap....

 

Complete s4 T2 into s5 N/A - RX7Club.com

 

Woo thanks guys, I have a build thread up. First friday of feb I think I am just going to get a full s4 turboII swap since I can get a deal on it. I will keep you updated on my build thread.

 

Sweet!! Make sure to make the build thread with lots of pictures and create it in the Mazda section. Thanks !!!!