T_Racer

iTrader: (1)

OK, I know this has probably been discussed a bunch, but in my searching, have not come up with an answer in the 1st or 2nd gen sections. I just came across a 89-91 na motor. oil seals bad, but turning by hand even got some good whooshes out the exhaust. WOOT WOOT!!! I guess that rebuild DVD will come sooner than later now.
My question is, is there any difference between S3 and S4 or S5 that would make this a pain in the *** to do into an 83? I know that I will need the front cover, oil pan, and modify the front engine mount plate. I am going sidedraft, so does anyone know if the S5 lower will take an RB upper or will I need a different lower intake? I will also be ordering the Pineapple racing 5/6 port sleeves, now just need a pipe off the header back to the actuators, correct?
Thanks in advance, and if i have overlooked a thread that has this info covered, just link it here and will go from there.

Cheers,
Travis

RX3SP

iTrader: (62)

It won't be too difficult to install the S5 engine in your FB. It's a pretty straighforward swap if you are using a carb. If you have the RB upper intake made for the 86-91 lower manifold, then it will not be a problem using the S5 lower intake. If you have the upper manifold with the GSL-SE bolt pattern, then you will need a GSL-SE lower intake.

T_Racer

iTrader: (1)

Well after looking at the motor again today, I am a little confused. The oil pump up front looks like an electric omp, not a standard mech. omp. So that is why I assumed S5, which should also have the lighter weight rotors. But the center iron has an egr, which would say S4. The guy, whom I trust and is actually a shop owner that is very well versed in 7's, as he owns three of his own, stated that the egr was a mid series running change, meaning sometime in mid-1990 it was eleminated, but some had it and some didn't. So, anyone know for positive if this is the case, or some other tell -tale? The 2nd gen stuff seems alittle vauge to me.

Travis

steve84GS TII

You really need to search.
The S5 engine swap has been covered a million,billion times.
The S5 non-turbo engine had EGR,the S5 turbo engine did not.If you have an electric OMP and the VDI intake manifold,you have an 89-91 N/A engine(S5).
It doesnt matter if its N/A or TII,its the same amount and type of work to do the swap.
In a nutshell,installing an S5 engine,then ditching the stock manifold and EFI is pointless.The lightweight rotors alone dont make the S5 engine desireable,its the whole 160HP,8000rpm,variable intake/wide torqueband setup that makes the S5 a great engine.If your gonna retain the stock EFI,you MUST retain the big electric OMP on the front cover.......and thats the S5's hangup.Please search on the subject,its been beaten to death over the last year.Ive done it,and a few others have too...its not hard,just technical.

firestarter810

So you can't eliminate the omp and run pre-mix? I'm going to do the same swap, and I have been searching and doing my research. I never intended to ditch my EFI, but I thought I could get away with running pre-mix, rather than modding the GSL-SE front cover to accept the OMP?

82transam

iTrader: (18)

You must keep the S5's electronic OMP in order for the ECU to function properly. Mazda designed it so that if the omp failed (thus providing no oil to the combustion chambers) the car would go into limp mode in order to save itself basically. You could leave the omp plugged in and tie it off to the side but thats ghetto and no one can tell for sure how long that will last with no oil in it...

no_name

I have been considering the same swap for the 160hp 8000RPM thing lol. I did not know about the OMP problem either. How would one solve this issue, if you can't use a GSL-SE Cover? Would you just modify the GSL-SE cover, or is there another way?

trochoid

iTrader: (6)

Hmm, nearly 900 posts and you're not familiar with Steve's S5, 300 hp, CARB legal swap? What's your next step?

no_name

No I am not. Mock me all you want lol. But at least tell me about it or hook me up with a link?

Druken

Just look up his name. He is a great guy and did a great job on his 1st gen. Deffinately someone worth knowing, just like rx7doctor and trochoid

steve84GS TII

Another thing to remember/consider regarding any 2nd gen engine......

Its best to replace the stock E-shaft thermo oil pellet with a "delete" plug.They are cheap and easy to install,and good insurance against the pellet sticking in the cold position.When that happens,oil no longer flows to the rotors for cooling and the oil seals, among other things,get fried.......probably what happened to your dead S5 engine.