RX-7racer

ok so i just picked up an s5 N/A engine for $375 with only 60000, it came with the trans( getting the drive shaft later on), all intake stuff, harness and ecu. My question i what else do i need to make a complete swap into an s4? and can the emissions stuff on an s5 engine be removed without immobilizing the 5th and 6th ports? any help would be great!!

p.s. this enigine is goin into a street car in which i wanna still have cruise control and a/c, and help w that would be appreciated to!!

thanks in advance, John

RX-7racer

ive been doin a little research of my own, and it seems like its just easier to swap in the s5 block, intake manifolds, and alternator, and replace the s5 front cover with the s4 front cover. meanwhile keeping the same electronics, throttle body, water pump and transmission. does this sound correct? from what ive read this is the only sensable way to upgrade to an s5 engine without going through the whole electronics nightmare. any help would be great

RX7 13B 4 UR AZZ

Yeah you got it right. Just use your S4 electronics and the S4 front cover and you are good to go.

sleeperRX7

What is the point of using S5 engine with S4 electronics? What are the plus and minus's of doing so? Thanks

RX-7racer

thats only if you are swaping an s5 engine into an s4. its way to time consuming and expensive to swap s5 electronics into an s4, because basically every part of the s5 electronics is different from the s4 ( different plug styles and pin combinations) and therefore everything must be swapped out if any s5 electronics are going to be used. to do that everything from the gauges, various dash switches, the ecu, various sensors and both the dash and engine harness (thats not even everything) must be swapped out, and if you dont have a complete set of s5 electronics it can be very expensive to track them all down. so just using the s4 electronics is the easier and cheaper way to go. By just swapping the block and manifolds you get the benefits of higher compression and a better flowing intake from the s5 bock and manifolds, meaning more power over an s4 block and manifolds.



so benefits: its cheaper than swaping to s5 electronics and you still get more power from the s5 block v.s. the s4 block



the minus's: you get slightly less power than you would get if you used the s5 ecu (which would require a complete s5 electronics swap because the s4 harness wont plug into the s5 ecu)

bumpstart

http://eomp.info/



this device allows you to keep the s5 front and its eomp and run the s4 electronics

- just swap the injectors over or change the plugs on the wiring suit the s5 injector, and remember to delete the injector ballast block if you have 1986-87.5 s4



no need to swap on the s4 timing cover and TB and turbo drain



much simpler,, and you retain a functioning EOMP despite whatever ECU choices you make

wanglerrx7

let me know if you need any S5 NA parts. send me a pm

RX-7racer

im just gonna get rid of the omp and run premix instead. The way i understand it though is that an s5 ecu wont work with the s4 gauges and various sensors throughout the car? so even if i swaped the s5 ecu plugs onto an s4 harness (if thats even possible) it still wouldnt work properly

bumpstart

only the realtek chip has the CEL code defeat for s5 ( so far )





this is what you asked ,,, yes?



granted you have s5 NA,, and and will lose VDI control without the s5 ecu,, but turbo owners are not in this boat





if you are doing the sensible thing and avoiding the troublesome s5 ecu by keeping the s4 one,, or fitting a cheaper aftermarket ECU

then this is what you fit,, it is no harder than a stereo install



http://www.youtube.com/watch?v=X4kIGRg24no



you use your s4 computer,, and delete any ballast resister,, and put the s5 injector plugs on



hassle free and not very hard or expensive or risky in context to a timing cover swap,

,, or even removing a fitted EOMP for a blanking plate and throwing out $20 each month on premix

is it ?



your other option is the realtek chips,, not so sure what options there is for NA,, but they do the CEL defeat and may prove easier options for those in the US

( but not so for those with foreign ecu codes )

88ROTA

hey man I got you covered on this!!! Just went through with a s4na to s5na swap.

All you need to do is first make sure your 5th and 6th ports are clean and that the port actuators are functioning properly (holding vacuum or pressure) also your vdi actuator as well, you want these to open right or your not going to be running right.

I kept my s5 timing cover and water pump. Bought a block of plate for the omp pump, sealed it with rtv black.

so now I run premix, its pretty cheep plus i know its getting the right lubercation when im revving that b*tch! lol!

got all new fuel injector seals, kept the s5 fuel rails but used the *s4* injectors. The s5 primary fuel rail is better, it wont lose the little screw in the pulse dampner at the end of the fuel rail which causes fires .



I also did away with emissions as well, BUT kept the hard metal fuel lines with the intake supports and cut the other crap off! looks SOOO much better.

Then I took one of my s4na trottle bodies and pulled all the extra stuff that you do really need here's a link it's at the end section, but the whole page is pretty close to the s5 emissions removal http://www.rotaryresurrection.com/2n...s_removal.html . Then I cut off that little nub that sits at the bottom of the trottle body (it gets in the way.



I also capped pretty much all vacuum nipple that were open and unused, also capped off the two coolant nipples one on the rear iron and the other on the back of the water pump.

There's only a few things you need to keep from your s4 to swap on to your s5 (s4 injectors& tps) but the rest like your oil level sensor, CAS, oil pressure sensor, water temp, water pump sensor, & your air intake temp sensor on the back of the s5 manifold on the drivers side of the motor will stay on your s5 motor to be swapped into the s4

harness. You could also use the s5 alt if you have it, just need to wire up the harness right which is hard at all.



Keep the s5 intake!!!



Next is the 5th & 6th ports & vdi.

This is what I did. I kept the s5 acv (lower intake manifold) there's a nipple that runs off it to operate the 5,6 port and the VDI and also kept the 5,6 port emission sensors off the s5 emissions rack .

Kept the stupid ungly air pump as well so it can provide air to open the 5,6 ports & vdi.

I bought 2 rpm switches that control when the 2 emissions sensors turn on to properly open or opperate the extra ports and VDI system. Picked them up from summit racing for around 89.00 shipped.

I set the vdi for 5200 rpms and the 5,6th ports at 3800 on the rpm switches.



hopes this helps have any problems pm me and ill be happy to help

check out the you tube link on my s4 to s5 swap I did the other week its the first start up of the swap .



http://www.youtube.com/watch?v=vodF3x46jtA