855m0n0

iTrader: (1)

I blew up my motor a couple of months ago and am finally getting around to rebuilding it. It was running in the neighborhood of 450whp when it went bye bye. The time before when it blew up it had a T-88 and was running 498whp.

I haven't torn the motor down as of yet but when we compression tested it one of the rotors basically had no compression. I had 2mm ceramic apex seals and the motor was build by Mandiville. I have decided to rebuild it myself rather than fork over another $7,000.00 to have Mandiville rebuild it. Plus, I think it will be fun. And, the old motor lasted 4000 miles from break in and tuning. Anyway. I am weighting selling my GT35R single turbo and supporting setup (all about 4000 miles old) and going with a 500whp V8 setup(which is very pricey to do right and also sounds like a V8) or rebuilding the rotary and trying again.

Since I don't know what failed in the motor yet I don't know if I need new seals. The ceramic seals were really expensive and I am not sure if they are actually any better than say RA seals. I might get the RA seals since I have heard such good things about them if my ceramic seals are toast. Not sure. Anyway.

My question is this; if one were was going to build the best (real reliable-ish) 13B-REW what would one put in it. Assume that money is not a factor (within some sort of reason). I already have all of the fuel, cooling, ignition, turbo, management, etc. mods that I need. I may go to a fuel cell or get that Hindson fuel tank mod to avoid having to always have more than 1/2 tank of gas. I had about 1/2 a tank of gas when the motor blew up and if that turns out to the be the cause then I am going to punch myself in the face.

The current blown motor already has a nice port job and hopefully I wont have to mess with those parts.

I intend to once again have 450whp or more. The car is very fun at that horse power level and I like it.

I dont know if these parts are needed or particularly splended but these are things I am pondering.

Different housings (forged if that makes since). Does anyone make something like this. Are they particularly better. How much do they cost.

Forged rotors (maybe lightend and or maybe lower compression). Does this make since to do?

Pineapple oil pan (it is $450 bucks, but supposidly it is easier to keep it from leaking, which my old motor did, and suppoisly it is stronger and doesnt let the motor flex as much). But that is just off the website. Anyone actually use one and have some kind of quantifiable data on it.

RA Seals and rebuild kit. Is this one the best. Like I said before I had ceramic seals before. Not sure if the extra expense is worth it or not. If anyone has RA seals/rebuild kit it would be nice to know what you think. If someone thinks there is a better non-ceramic option that is supperior to RA/Ceramic that would be interesting to hear too.

Last but not least. Who is the best dyno tuner in the USA? I was thinking about driving to RX-7.com's store (TX I think) or paying to fly someone to ATL, GA. I know everyone has an opinion on this one....

thanks for reading my long *** post.

855m0n0

iTrader: (1)

I was also thinking about adding water injection for extra protection. I think that the Power FC can control that. I am not sure about if it can control it or if I really want to add another varible.

alberto_mg

So was it detonation that killed the motor? There definitely seems to be an interrelation between the overall power output of the motor and its longevity. Some people who are after high numbers like you have had more luck with a V8 LS1 swap. It sometimes does sound pretty appealing... I've been reading up on it lately on torquecentral.com.

As far as RA seals, you might want to do a search in the Rotary Performance section of the forum. I think there were a few threads with some people that had problems with them. While I'm no expert, it seems that with that much boost you might want to consider some 3mm seals. A lot of people running closer to stock boost levels swear by Mazda 2mm seals.

What is your current fuel setup? I've never heard about a problem running less than 1/2 a tank of gas. I've heard people road racing having problems with fuel starvation when under 1/4 tank, but never 1/2 tank and never on the street. Seems like some people running that much power have tapped in the rear of the stock fuel tank and run larger lines to the motor.

As far as water injection, it definitely seems to add a degree of "insurance" when running higher HP and boost levels. There have been a few threads from people using WI and having better results from a reliability standpoint. I wouldn't tune with the expectation for having WI, but its ability to cool the intake tract and lower knock readings and decrease the chance of detonation seems to be worthwhile.

As far as tuning, I'd check out Steve Kan (aka pluto at Gotham Racing in TX), BDC in TN. I've also heard of a couple of people in FL or NC but hopefully someone else will chime in with more info on that.

If you have the skills to build the motor yourself, might want to give it a shot. Once you figure out why it blew hopefully you can fix that part in your next build.

rynberg

Instead of wasting your money on a bunch of fancy parts that won't really help, you should be running C-16 and a good tune from Steve Kan or Brian Cain. Water injection is a very good idea, but don't tune the car for it. Just use it as protection. Don't take ANY shortcuts on any of the systems.

All the fancy parts aren't going to increase reliability more than running good fuel and good tuning.

2Lucky2tha7

iTrader: (3)

Ceramic seals, from my understanding, break under detonation much easier than even the stock mazda seals. I would definitely go with a 2-piece 2mm apex seal. I have 11,000 miles on my rebuild with the RA seals and they seem to be just fine. There's always the option of the Mazsa 2-piece seals as well but I honestly couldn't tell you which one is better. From my knowledge, The mazda 2-piece seals have broken but I have yet to hear of a set of RA seals break. Maybe I'm wrong. I personally like the RA seals best.
I ended up creating my own rebuild list (which I still have) which basically consists of the RA o-ring kit and RA seals, and most of the other parts ordered from Mazdatrix---piece by piece. Maybe you'll be just fine with getting the RA master rebuild kit.
I would personally stick with the stock 9:1 compression rotors for your build and if you REALLY want to, then you can send your rotors to Racing Beat to have them lightened and or have the gear locked in place which keeps it from "walking" out at high rpm's. In your case, however, I think you'll do just fine without the locked rotor gear modification. If you do decide to get your rotors lightened, then you will have to send them the entire rotating assembly so that it can be fully balanced. Or you can just buy a fully lightened rotating assembly from Racing Beat.
The only other option you have for the side housings would be to buy the aluminum side housings from Racing Beat, but of course that all adds up and merely provides you with saving weight in general. There is no real "gain" from having these in my opinion.
If the rotor housings have become damaged, the it would be a good idea to invest in a new set of rotor housings but this will cost you about $900 however. I would try to re-use your existing ones.
The Pineapple Racing oil pan is a good idea if you can spend the money on it.

If you have any questions about your build, don't hesitate to PM me to let me know.

Brian

Herblenny

iTrader: (13)

If you are looking for "reliable-ish" engine, go with streetported engine with 2mm OEM 3 piece seals and don't turn up the boost!

If you want to make power and want to rebuild it every other year or less, go with "Indestructeble Apex-seals" (https://www.rx7club.com/general-rotary-tech-support-11/indestructeble-apex-seals-488606/).

855m0n0

iTrader: (1)

I just the motor out today so I dont know what killed it yet. I should know in a week or so.

My fuel system is porsche pump, boost dependent fuel press regulator, new line from fuel pump to engine bay, 1630cc (rc checked) secondaries, 550 primaries. At 15psi on the GT3540R I never see more than 75IDCs and my fuel pressure is very stable. I don't believe that the issue is fuel related.

The fuel tank thing has to do with the fuel pickup design on the FD. Hindson's site has something about iit. Motortrend also mentioned it in their recen article about our car (It was in the zx06 vs. Viper issue from like 2 months ago). I never saw my fuel pressure guage do anything odd at 1/2 tank. I never let the car go below 1/3 tank so I don't know if the issue exaserbates with less fuel or if the problem even exsists.
Here is a link to hinson's thing about it. http://www.hinsonsupercars.com/FuelSystem.htm

Anyway. Thanks for the input.

Old Slow Coach

I concur with this advice. There are 2 piece seals, but go with the 2mm 3 piece! Street port, not race port.

855m0n0

iTrader: (1)

The motor is out and it looks like 1 apex seal in the front rotor has broke.

RX7 Japan

I had one break and it scored the housing and the face of the rotar. Pray to the rotary gods that when it broke it shot out the exhaust w/out too much internal damage. (but then there can be possible turbo damage)

855m0n0

iTrader: (1)

the turbo looks good... We are going to measure/fully inspect the internals soon. Nothing looks f#$ked up so far other than the apex seal.