What's the easiest way to fit a RX8 block into a SA/FB ? I have some question's and if anyone has got any pic's that would be good !

1) Can you use a 12a front cover ?
2) Can you use the sa/fb oil cooler and oil line's ? If not : Maybe a beehive oil cooler ?
3) Can you use a 13b gsl-se sump and oil pick up ?
4) Would a SA/FB gearbox bolt up to a RX8 block ?
5) Can you use a 12a lightend flywheel on a auto RX8 counterweight ?
6) If you can use a 12a front cover are you able to run a cas or dizzy ?
7) Would a 12a waterpump bolt up ?

 

1. not sure. the irons are a different thickness, so the front cover *might* be a little shallower.
2. if the front cover swapped over, probably, if not i think the Rx8 uses a banjo on the front like an FD, so you might have to make something, pretty simple though
3. dunno
4. yes
5. yes
6. sure, worst case you'd need to put the CAS/dizzy drive gear in.
7. the FC water pump should

 

The easiest way to get everything functioning in the FB would be to do the Dizzy and carbeurator setup. Although I dont know all the details of the install, I did see pictures of a setup as described.

Personally, I'd probably splurge for the EFI intake with a standalone fuel manager, with stock dizzy.

As a note, Racing Beat makes engine mount adapters from 12a to 13b, so if the 12a front cover doesnt work you can swap the mount over to 13b and use a 13b front plate (gsl-se)

RX7 1975-1985: Engine - External: Front Engine Mount - 12A to 13B RX-7 Engine Conversion -

 

1. you shouldn't have a problem bolting it on the MSP, but you will still need to fabricate or modify a mounting bracket because like j9fd3s alluded to, the MSP is a little longer than the older 13Bs.

3. it's possible that you may need to fabricate the oil pan due to the difference in length. so far, i have not been able to nail down an actual figure for the difference in length though. i don't know if the pickup tubes share the same bolt pattern.
for this one, i'm not 100% sure (and now my Rx-8 is in storage so i can't confirm), but i think there will be a major leak to contend with because the Rx-8 front cover incorporates the water pump housing. essentially, when you delete the Rx-8 front housing, i think you're also deleting the upper mount point for Gen I or Gen II water pump.

 

The Renesis mounts on the center plate correct?

An FC subframe might make the swap doable if the front cover is specific to the 8.

Would be a hassle if a swap tho. Have to do the entire front of the car at once.

 

Awsome, Thank's for the reply's/info ! I was able to do some searching tonight, This is what i found:

You literally only use the Renesis block and intake manifold. You swap on a different cable actuated throttlebody. You use 1st gen oil cooler lines and coolant hoses. You use a 13B water pump (the Renesis pump sucks anyways) and housing. You keep the radiator and oil cooler (hopefully not the bee hive style) from the 1st gen. It's simple.

It is almost literally as easy as swapping any other rotary into the car. Since you are using the 1st gen front cover, you also can use either a distributor if you are really lazy or a 2nd gen crank angle sensor. While the front cover is off, be sure to swap the cas gear onto the front of the Renesis crank. Simple. Now you have the option of either a carb assuming you can make your own intake manifold, fuel only efi, or a complete standalone efi. Even a lowly Megasquirt would work fine but anything else that works with a 2nd gen will now also work with this too.

The exhaust is no big deal. The Renesis exhaust manifold works fine. You only need to have a new "downpipe" made to go between it and the cat, assuming you are running one. Everyone else has either bought or fabbed up a cat back system so that shouldn't be a problem.

There are no more tuning problems as the RX-8 ecu is nowhere in the picture anymore. You can still use the stock RX-7 transmission. You do not need to swap. You will need to use an aftermarket flywheel and an automatic Renesis counterweight though. If you wanted to swap to a TII tranny, you could even use a TII clutch and flywheel. They are the same. https://www.rx7club.com/1st-generati...-668331/page3/

By the look's it shouldn't be to hard haha, But yeah not sure what i may do next .... Pic of the block i was looking at, Almost complete block in bit's with new rotor and housing, Droped a rear seal at 60k.



One last quick question, What is the stock HP for a 4port and 6port RX8 motor ? Cheer's.

 

purely from my memory ...
232 to 238 (depending on year) for the 6-port
212 for the 4-port

a small note on the 6-port is i've read in a few different places where Mazda may have fudged a little with that 238 on the early cars, so i think if you figure about 230 across the board you should be good.

also, judging from that photo, my concerns on the water pump are invalid, so disregard what i said before.

and by the way, do you have link for that article you quoted? i'd like to add it to my collection.

 

the only real tuning parameter with the Rx8 motor you need to be careful of is EGT, you need to keep it under 900C, there is some phenomena where when it gets too hot, the side seal springs break.

other than that, beat the F out of it, i seriously considered one instead of the PP, but in 2005, the Rx8 motor was $$$$$

 

Yah cost has been the most prohibitive factor in considering it for a swap for me - hence the S5 fb setup.

This is honestly the most laid out, straight-forward description I've yet seen of the swap - the juicy bits of the post start here:

https://www.rx7club.com/1st-generati...2/#post7107825

https://www.rx7club.com/1st-generati...2/#post7108416


S1sevenNZ, do you have a link for that exact quote you posted, or is that your summary? Either way well done!

Honestly though I think that if I were to do a renesis swap I'd do it in an FC. That's not to say an FB renesis wouldn't be ultimate - it would. Actually you know what, scratch that, put a renesis in ALL gens and have a fleet

 

oh BTW the 2009-2012 engines have a vastly different front cover/oil pump setup, so a GSL-SE/12A front cover will not work with these.

 

Good call.

 

Thank you. Yep : https://www.rx7club.com/1st-generati...-668331/page3/

Yep it's the same link as your's, Quote is on page 3 2nd post down. https://www.rx7club.com/1st-generati...-668331/page3/

 

... Is there anyway to tell what year a 8 block is when it's stripd down ?

 

yep! the 09+'s have 3 metering pump nozzles in the rotor housing, and under the front cover the front iron/oil pump etc is totally different, the oil filter is moved to the front.

the rotors and eshaft are the same. the rotor housings are different, but useable, so really you could probably just swap end irons to the 04-08 style, or use different engine mounts

 

Any benefits to the newer style? I'm sure they made the changes for a reason, but the only diff i can see is 2mpg less economy and the same 232bhp.

 

the oil system on the Series 1 engines was utter rubbish! it's one of the things that pissed me off to no end with the Rx-8. the oiling (or lack there of) is one of the things they attributed to the low mileage wear and failures. the metered oil jets did not provide adequate coverage for the apex seals. i believe the pump they used was the Gen II N/A spec. so they changed things on the Series 2 engine.

 

Cheer's man. The seller said the block is a 99 - 2001

Ok so premix it is

 

if you go look there is much debate about weather premix actually helps, it seems like it doesn't matter.

the one obvious fault is that the stock oil pressure in a 03-08 engine is 70psi, so you should put the FD/S2 Rx8 regulator in it, for the 110psi

 

That's ok, I already premix now .. Have done on all my motor's (except the stock 12a i had), So defintly get oil pressure bumped then. I wonder if the stock 8 exhaust manifold will fit in a rhd sa ?

 

 

good infoo!!!