Pre-Build Questions
 

Hi All,

After 5 years of RX ownership (on #2 now) the time has finally come to go FI :)

I've spent a reasonable amount of time researching as much as I can (mainly on this board) and have come down to a handful of questions to which I either can't find answers, or there is so much conjecture I can't work out which way to go!

I've been haunted by the saying "performance, reliability and cheapness - Pick two" - So I've been selling all my goodies to overcome this (R3 recaro interior, R3 side skirts, etc :( ).

It's the greddy kit with the BNR turbo, greddy bov with recirc valve and Cobb for the tuning. (Injector wise, running green/blue/blue as per MMs recommendations)
Also have D585 coils and an AEM intake (will be modded to fit)
(Still need to grab water/meth kit and gauges.)

The motor is on it's way out anyway (reasonable amount of blow by + low 6s all around) so it will be rebuilt too.

I'm hoping for 300whp @ <=10psi.

Questions:

-Apex Seals
Soft seals like goopy worth it? Or mazda seals fine?

-Side Seals
Presumably Mazda long seals - but is a larger clearance required in FI application?
Also given the extra heat involved - Atkins offer cryo treated mazda seals + springs - are they worth the extra $$ ?

-Corner Seals
So much choice.. atkins solid/atkins cryo/mazda/etc - Any suggestions?
(I'm leaning towards stock Mazda at the moment).

-Porting
My engine guy uses the racing beat templates, presumably still worth doing - but anything worth noting/improving?
(I know petit mess with leading plug holes and coolant flow around the exhaust port)

Also annoyingly not one rebuilder in the UK does anything with the housing surface, if they’re “in spec” then they get reused :/

-Fuel Pump
Currently running stock, but have an S2 pump kicking around - Would this be up to the job? (appreciate a bit of modding is required)

-Plugs
NGK-5255 (BUR9EQP) all around? or just leading and re9bt trailing?
Or even just stock for trailing?

-SOHN Adapter/Atkins Thermal Pellet/Mazmart re-medy water pump+thermostat+oil pressure regulator
All of them sound like great ideas - In reality which are worth doing?


I know there is a search button, and I've nailed that thing recently! Just looking for advice from people who are running FI and can advise on what has/hasn't worked for them.

Thanks in advance!

Check it.

Green, Blue, Blue? I disagree. Blues in the P2 and stock elsewhere is plenty.
I’ve got greens from a previous breakers yard adventure, I don’t think the flow rate was the deciding factor - more the spray pattern/atomisation.

The AEM will work, not very pretty IMO. And by D585 do you mean a homemade kit?
Yeh :( I figured it was better than the “mushroom of doom” that came with the kit.
Well, I made a D585 kit for the last car, but this one is put together by a UK rotary specialist. (genuine ac deco coils and custom magnecor leads so I don’t foresee a problem).

Mazda seals IMO, the jury is out on Goopy IMO.
I thought that may be the case, I’m not against using Mazda seals at all - just a little worried how resistant they are to detonation. (Although clearly trying to avoid detonation in the first place is the aim of the game)

OEM Mazda side seals cut to fit IMO. There has been issues with the cryo treated apex seals, I personally don't trust Atkins quality control (checked by hand supposedly by Dan Atkins)
Damn, that’s a shame - sounded like a good idea in theory. The only other atkins made/supplied parts I was looking at using was their o-ring kit due to the saving over Mazdas.

OEM Mazda again
Cool, Was leaning that way anyway.

Every builder is different in terms of what they will and will not reuse. The quality of the porting and its gains depends on the person doing the porting IMO.
This is going to be a thorough rebuild in terms of what is being replaced - and definitely true that each builder is different. I could probably count the number of FId RX8s in the UK on my fingers, the quality is not so much the issue as the knowledge in this area.

I would run the improved S2 pump for sure
Great, and this *should* be ok for my goals ? (circa 300whp)

highly debated, but I run stock trailing in the leading and trailing positions. I have had no issues
Yeh this was one subject I found little conclusive info on; but good to hear this as those plugs are very easy to get hold of here.

IMO the Re Medy water pump is a waste of money, I had it, it failed, I switched back to a stock pump, saw no difference. If you track then it may be beneficial at consistent high RPM (not happening with a turbocharged car for the most part). The thermostat also seems pointless but why not. I would actually look into upgrading your fans if you want to cool down quicker and better in traffic temps. Thermal pellet (talk to builder), higher oil pressure I recommend but again, talk to your builder.
This is why I posted this :D Great to hear real world reviews, and also gives me $250 to spend on other bits.
I like the idea of the thermostat popping over a few degrees earlier, and granted its not much $ but again if there is minimal impact then it could potentially just be more unnecessary spending. Are the fans actually worth upgrading? or is getting them to come on earlier sufficient? Thermal pellet makes sense and I actually recall my builder agreeing on this in the past, so didn’t really need to post :/

I was thinking SOHN adapter as I would prefer to run fully synth for the sake of the turbo, but we don’t have brands like royal purple easily accessible over here so would be taking a bit of a stab in the dark in terms of what’s ok to run engine wise.

I'm hoping for 25,000+ miles out of it before any major issues - obviously anything could potentially happen at any time, but is this a realistic expectation? How many miles have you got on yours?

And thanks for taking the time to respond.

goopy apex seals are proving to be good, Dondo/Eazy have rx8 height seals in their turbo rx8 and its seen track days.....no issues

I have solid corner seals due to going with rx7 depth goopy apex seals, things are running great

most of the other stuff has been discussed.....

I wouldn't put stock Mazda apex seals in an FI rebuild even if i got them for free ... The risk of them breaking and destroying the engine is too great .
I also went with rx7 height apexs after i saw how much side wear there was on stock height seals after moderate kms.
I would also recommend dowelling ... cracked front iron and chance of coolant seal failure can be minimised

That was my main concern over using hard seals, if (when) they break - it's game over.

I do like the idea of using the 3mm seals but I doubt I can find any rotary guys here in the UK who are feeling brave enough to mill some rotors for me! I'm assuming you also have to go with matching apex springs?

Dowelling looks cool; albeit rather close to the water jacket! Seems like a good idea, but given my goal power wise is is that likely?

Either way food for thought and I'll be ringing around tomorrow and see who can do what...and for how much

Wouldn't recommend 3mm seals . Just use stock dimension rx7 height seals . I went with ALS ... which seem to be working well on 16psi and 375whp.

I was shocked at how little wall thicknesss there is after dowelling ........... doesn't seem to be an issue though . I think if you stick to your goal .... dowelling may be a little OTT but ...... we always want more .... don't we ;)

Ahh ok :) Presume some milling/edm is still required to make them fit?
What springs would you run with them? and corner seals?

I'd not actually looked at ALS seals - but having had a quick look, they get some serious love from 7 owners! (Saw the pic of one twisted like a bow and still in intact!)

hehe it's true, but we have LOTS of speed cameras and some great twisty roads here :P arguably an SC would be better suited, but my goal should keep me happy for a while :D Plus its a bit of a novelty given how few FId 8s we have.

I'm assuming Mazda oem for everything else (i.e side seals) ?

Upgraded studs is popular too...

So many opinions, it makes it hard :).

One or two people having some success with the Goopy seals in a turbo 8 is not enough for me personally.

I am on stock apex seals, 20,000 miles boosted, great compression. but it's more about the quality of tune and who builds the engine rather than the mileage IMO. I would only use ceramics if I used new housings. And even then, that is a big IF. I doubt I would ever run ceramics just due to little benefit IMO versus cost.

I know of three or four boosted RX8 engines with ceramic seals that went kaboom, none were high mileage. And even if I did run ceramics and the apex seals didn't fail, I still would not reuse ceramics so I just don't see the point really.

RR also recently tore down a low mileage Pettit build (poor tune on SC 8) with the rotors milled to accept 2mm RX7 seals and they broke making many other parts unusable.

Like I said, talk to some builders and see what they say.

Put it this way ... :

*aftermarket apex seals will not last as long as OEM seals.
BUT .............

*Boosted engine will not last as long as an NA enigine

*Aftermarket (bendy) apex seals will last as long as the rest of the engine in a boosted application.

*OEM apex seals break under detonation destroying most of the engine as a result

*Aftemarket seals don't tend to break under detonation .

*Detonation is hard to avoid in a renesis engine running a reasonable amout of boost

*If you are rebuilding your engine anyway... aftermarket seals don't cost any more than OEM

Now.......... I should draw a nice flow diagram that will lead to the inevitable conclusion .................

I agree ceramics are not what they seem. Dondo first had ceramic seals it blew up on the dyno, then I told him to try goopy seals, and he is running strong. Brettus hits the nail on the head. We like bendy apex seals ;)

Doubled checked what RR posted on FB and it was a Pettit build with rotors milled for 2MM RX7 seals and they did break. Not sure what Apex seals pettit uses but I think they claim to use some type of treatment on them to make them stronger.

https://farm6.staticflickr.com/5579/...02d70261_c.jpg

Also, supposedly the damage on this rotor was from a previous failure and was reused.........

https://farm4.staticflickr.com/3923/...9ef12fd1_c.jpg

As any RX7 owner can testify, it's no guarantee against doing something wrong/stupid. It is stronger than the RX8 seal, less prone to warping across the face, and less prone to wallowing out the rotor slot.

Best advice I can offer: you have no idea what you're doing. Instead of playing interweb genius researching parts from other people who have no idea what they're doing but are always happy to pipe up any way, instead research out a known quality builder of high reputation and follow their advice on what parts to use/purchase. The worst thing you can do is shackle a builders hands with your poorly informed choices. Keep your mouth shut except to ask intelligent questions and you will learn a lot in the process.

i have rx7 seal in my car, I don't know which one, but I was about to use super seals, but my builder told me that the quality got worse ..this was almost 3 years ago..and I asked him about goopy, and he said that he had one in his dyno, he built the engine in the car, and did the dyno, it blew at 30 psi (RX7 engine)..something like that..then he recommended me the new seals, RX7 seals, I forgot what company made it, from Australia..it is stronger than the super seals, and till now, it's good..i have turbo, and it went lean, many times, and it's still fine,, but I did many things..

the moral of story is that you should go to the builder or to the people who have good experiences toward building, and get their advice..as teamrx8 said..
steven

that's an odd rx-7 seal, most the seals I see have more material and have a bit of a flat spot, instead of a point on the small bit of the apex seal.

I don't need 30psi......
http://atkinsrotary.com/store/images/P/ARE13-2-01.jpg

Couldn't agree more - However as mentioned before, I can probably count on my fingers how many FId RXs there are in the UK - as a result, our builders just don't have the experience of turboing the renesis. We have a decent number of RX7 specialists, but that's a different story.

It could easily end up being a case of the blind leading the blind.

The knowledge is on this forum where I know respected builders frequent; realistically do you expect I could just ring up the likes of racingbeat or pettit and ask them the questions I have above? knowing full well I would be unlikely to be purchasing parts or services from them due to logistical constraints. I find it unlikely.

Given your logic above then it would seem pointless ever asking any question on any forum :scratchhe I asked what I believed to be intelligent questions :dunno:

I would call as many legitimate builders as you can. You will get many different responses (I have spoken to most of them and it is downright discouraging). There are also different level of builders and the more respected ones you will not find on internet forums honestly and they will be a large initial investment but possibly worth it. At the end of the day it comes down to how much you want to spend and what short cuts you are willing to take.

Well said !

not at all

I offered my best advise on where to find the most intelligent answers, it might be the only one you will actually receive here ;)

cuz the only intelligent rotary people in this world are the ones who work on rotary engines for a living ................................. right ;)