Perhaps you should follow your own advice and read up on the BNRs, Mr. 16 posts. I would elaborate, but "to long to explain."

Sometimes the amount of misinformation propagated by some of the parrots on this forum astounds me.......

 

how much do the BNR stage 2 cost? Also how many psi can they handle and can you run them in the sequential mode?

Thanks

 

He won't be - I will assume he is talking about the RX7 SP or SPII which seems to be called "Bathurst" version a lot down this part of the world, possibly because they were often raced on Mt. Panorama in Australia. Who knows.

Anyway, as far as I know they can handle quite a lot of boost and supply very good power in doing so, though I'm not sure their boost threshold is as good as the stock twins.

I have some information somewhere about the more specific details about them - can't remember off the top of my head, but to give you an idea..

Mazda RX7 SP Advert

 

$1650 with good core.

17 psi all day long on 93 octane for 125mph trap speeds, 20 psi for short blasts.

Yes.

 

J,

What boost level did you make the 381 and 320 torque? That might help people compare with my 99 twins that I dialed im pretty good at 14.22 (1.0 on the PFC). Mine was 363 and 320 at the above boost level. We could also see what hp were were making at low rpm points. Help seperate crap from facts

Tim

 

Well said. It seems like it is getting worse by the day.

 

If thats not the best quote i've ever heard about this forum... i'd die

 

You know your ****, well done. Most fools would think I know nothing..........

last year in Paris, I spoke with Mr Terada about the hard to find "Bathurst turbos'" & he said that Mazdaspeed sold the remaining stock by the late 90's. (Y.Terada was the ex Mazdaspeed president. Now Auto-exe)

I know of 2 sets here in Sydney & they are wicked. As you would expect with significantly bigger turbo's, they take longer to spool. Once on boost, they grunt up to 8000rpm with no dropping off like the standard turbo's.

Mazda Australia brought some of them in for the RX-7 SP to compete in the Bathurst 12-hr of 1995 (which was changed last minute). As the RX-7 had won the Bathurst 12-hour on its first year of introduction in 1992, it also won in 93 & 94 hence the "Bathurst" name plate.

Finding a set would be a major score as they are big enough to be rebuilt with reliability & while still using the normal twin turbo operation, they feel great around town.

 

i dont know if this is 100% correct, these figures are from a local magazine. (SP33D 6/03)

rx-7 SP 240kw @ 1.0bar
series VIII 270kw @ 1.2bar

 

I purchased a set of the BNR stage 3's a while ago. I had installed them and to be quite honest they did smoke like a friggin freight train. However when i did call Bryan about it he offered the banjo bolt fix and that still didn't work. Bryan was well aware of this issue and is now currently rebuilding them for me. I hope this will fix the smoking problem. Now to my main point, When i was breaking in my new engine and only running 6lbs of boost those stage 3's pulled hard as hell!!! at 6lbs they pulled almost as hard or as hard as my stock twins in perfect shape at 10lbs. Bryan is the best to deal with and I am completely confident that the smoking problem will be resolved. So, my .02 the best bang for the buck by far are the fixed stage 3's.. I will be dynoing as soon as i get them back and will post results, but as for the sheer feel of them.. Was awesome!!!.

 

If your thinking single but are going to stay twin for now then I would go with stock rebuild until you go single. If your thinking about it it will happen sooner or later so dont wast your money on something your not going to want later anyway, with said I would keep what you have if they will get you by and save your $ for a single. I am twin with fresh rebuild and dont plan to go single.

 

As a comparison...my 99 seq twins made 270 ft/lbs to the wheels at 3100 rpms at 14 psi. Looking at J's posted dyno sheet, the M2 bb's are at about 230 at the same point and his are seq set up, although I'm not sure what psi he was set for on the dyno run.
at 6000 rpms, J's at 305 rwtq, I'm at 300.
Tim

 

tim are you stock motor or ported?

 

Yes, the '99 Type RS twins run sequentially spool up sooner and faster (especially with straight-through exhaust) stock twins, M2 BB and BNRs. If your FD3S is a street-machine, and hate turbo lag I do, you will LOVE the '99 J-spec twins--nuff said. Yes I prefer brand new twins over rebuilds, which is why I'd never do a BNR or M2 (no offense to those manufacturers of course). AFIK, Tim Benton's results are the only '99 J-specs I know of with a bona fide dyno graph to back up the J-specs' performance level (check Tim's mod list for an appropriate comparison).

As for single turbos, that's going to depend on what you're interested in. Ultimately the single turbos make more peak hp than twins, not to mention simplifying the turbo control system (you do away with all the twin turbos' sequential system's turbo control solenoids and actuators). There's no getting around the singe turbo's spool time though. Even the GT35/40s don't begin to spool up until 3500 rpm. That said, may road racers on the forum are switching to singe turbo because their FDs spend most the tach time between 3500 and 7500 rpm anyway.

 

J,

it's a stock motor, which helps me down low compared to the ported motor on your car. Also I don't think J's car is dialed in totally...although down low (3k to 4K) it won't change that much. Even with it not dialed in, you can see J's car makes more torque and resulting HP (all related to torque and RPM) are greater. I've got mine as close to the edge of making safe HP. Nice 11.4ish A/F with timing advanced a little for my car and sill under 40 on the knock meter. If and when J get a chance to dial his in better, I think the top end performance difference will be even greater.

Tim

 

does BNR do anything with 99-spec turbos?? i just bought 99-specs and was wondering if they could upgrade them?

 

I talked to Bryan about that and he said another benefit the 99's have over the 93-95, besides what's been mentioned here, is the fact that the nut holding the wheels together are, if I remember correctly, lefthanded, whereas the stockers are righthanded. I seemed to think that was better for reliability (ie. not coming apart as easy from the bolt backing off) but had not effect on the flow characteristics.

Tim