DaiOni

Tagged this to the end of another post, but I'll try here as well. (also searched but couldn't find a topic).

Is the 255hp everybody claims a factory figure??

Now, I'm assuming that the US FD would have been detuned to suit the lower octane fuel. On top of that there is the pile of pollution gear. Any other restrictive add-ons?

The equivalent JDM also makes 255hp - yet does it without all these 'chokers'. (in 95 it went up to 265 and 280 later on).

How did they achieve the same power level?

(ps: not a dig, I am truly interested)

kyle@insight

That's what mazda rates it at, the dyno numbers they produce in stock form seems to match up about right too. All the polution and solenoid crap is there of course, but I'd think that would really only rob you of some midrange power, maybe 5 peak horsepower at most.

DaiOni

well a stock JDM is usually considered good for 13.6 (and have seen this proven) - what is a US FD good for, stock?

mcmeel

I ran 14.04@98.24 recently, completely stock, incuding factory tires (that are really old). Motor has 28k miles, and it was around 70 degrees outside. 60 foot time was 2.149.

kyle@insight

I've seen stock FDs go 13.6, that was with some hellafied driving tho.

cow

"Hellafied"?

I always thought they were good for high 13's, which sounds about right for the power/weight. Just needs a good driver. They aren't drag cars though.. -_-

DaiOni

"They aren't drag cars though.. "

as opposed to what? a top fueller?

The numbers they run in japan (particularly, vs $$$ invested) would say that they can be a pretty damn fine drag car.

there's at least a couple in australia running 7s. Isn't the record FD a 6 second car from puerto rico or somewhere?

but you're right they're not drag cars from the factory - but what is?

cow

No, I meant that they are better suited for roadrace/auto-x than drag racing. Drag racing should be left to cars that can't handle.

Solid liveaxle design is preferred to an IRS when drag racing.. mainly because of durability. I agree that they can make fairly good power for money but there are better cars out there. To me, a Supra is more of a drag car while the FD deserves to be on a real track.

However, the best drag cars are domestics, bar none. That's what I was alluding to.

DaiOni

I agree with your sentiments whole-heartedly. But I disagree about the supra. When I think of a supra I think of straight-line speed (and a looong straight at that). I think it's interesting to see the drag reverence they have in the US - it doesn't seem to be reflected anywhere else.

cow

Oops, double post.

Isn't straight line speed what drag is all about? lol. Although I guess you are referring to TOP speed.

DaiOni

hehe, yes, guess I should have clarified that.

when I think of what a supra is good at - I think of the JUN supra.

When I think of 'imports' that kick **** on the strip, I think mazda first and nissan second.

But, yeah, you can't beat good old capacity combined with some form of forced induction...

...but a lightweight rotary sure does a good job of it

cow

Every Supra I've ever seen has been a drag car (or a dyno queen, heh), so that's probably my first pick. After that I'm not really sure.. I guess Nissan would be my 2nd also, although I don't immediately think of Skylines since we don't have them here. Mazda would be low on my list, since I would never take a 7 to the strip, except maybe to get a couple of baseline times. :P

kyle@insight

hmmm interesting convo here. Let's break it down.

How is the supra more suited to be a drag car? Sure it can make huge power but it's just as capable cornering as an FD is, well, close. I believe the numbers I've seen are .95 stock which is by no means slouching in the corners. The stock 1/4 times the supra is a bit quicker too. It's just as capable on a road course, just not as developed as they're capable of insane power levels. 90% of supra owners buy their car with the intent of going stupid fast.

FDs most people buy with the intent of building a well rounded street car, or just something insanely fun to drive. I think we have a mixed group. Some people like huge singles, some like the responsive nature of the stock twins and the out of the box cornering capability. However, let's break down the actual engineering of teh chassis. IF you purchased an FD with the intent of building a drag car, you actually made an excellent choice. The 50/50 weight balance and the way the suspension geometry is set is an ideal platform. Not to mention the Aerodynamics. The cars are able to 60' very well, the weight transfers and falls just right. So in all actuality, while the FD may make a great road course car (which by all means I prefer), it's also a very capable drag car.

Just some food for thought

DaiOni

yeah, interesting global differences.

In japan the 7 is quite often the a 'drag queen' :p
There are a LOT of cars running 10s. Yet it is also a champion drift and circuit car. It's the only real allrounder I can think of. Doesn't have to be one or the other - but will obviously do best when it's dedicated to one field.

In australia rotaries have a long history at the strip. And the third gen is no exception. While the car definitely has the goods to be a top notch handler - it's also light-weight from the factory and has a twin turbo rotor - two fantastic qualifications for drag racing.

Are there (globally) the same numbers of supras running times like the FDs? I don't think so. Great cars though, I have a lot of respect for them.

DaiOni

...and I'm not saying that the supra is not capable of the same - just that the rx7 has achieved more so far - which is a good reason not to discount it as a weapon on the strip.

a very solid 3L is obviously a great starting point too


"The stock 1/4 times the supra is a bit quicker too"

US only though (feels strange to say that - usually you guys get the bad end of the deal!)

kyle@insight

Absoluetly correct. The main difference is that we got a nice set of turbos on the USDM supra that are capable of boosting to 22psi. The J-spec supras have ceramic turbos that blow at STOCK USDM boost levels.

cow

Good points about the RX-7 as a drag car, I definitely didn't consider the weight balance.

The main reason I personally consider the Supra a less than ideal handler is it is, well, a boat. 34xx lbs, or something to that effect. The 7 on the other hand is a TRUE sports car.. light, quick, everything you need and nothing you don't.

The supra is more suited to drag because of it's ridiculously overengineered motor, mainly. Like you said, most people get them to go really really really fast.

rpm_pwr

This has been done to death but here we go again:

Power-related differences:
1) US has pre-cat (JDM DOES NOT)
2) JDM has bend around steering column (v. narrow)
3) US has EGR on LIM (JDM DOES NOT)
4) No AWS on JDM (makes SFA performance diff.)
5) ECU

Boost I'm not sure. My old JDM made 12-10-12 which is more (2psi) than the US version but I think my ECU was modded.

For reference oz -spec differences:
1) Pre-cat
2) Typical steering column bend
3) no EGR (havent checked this personally)
4) AWS
5) very low octane tuning.
Boost 10-8-10

... and while I'm settling things, the "efini y-pipe" was not fitted to efini RX-7s until 1999. Prior to that they all had the same y-pipe (and x-over) as the rest of us.

-pete

DaiOni

rpm_pwr: I'm aware of the differences - just not sure if the US cars actually make 255hp stock - given those differences.

I'm sure it's not far off (I've heard 235hp mentioned in relation to the oz-spec) - but if they are making 255hp - how do they make the difference?

does that make sense?

rpm_pwr

hehe ok well that's a bloody good question then. Yes they do have 255HP stock. Anthony Rodriguez (from Maztech) once posted on here that he was SURE that the US FD's were pulling their extra power from more than just the EGR and exhaust, and the very fact that JDM's don't even have a pre-cat suggests that too. But there's always the steering column bend.

So maybe steering column bend JDM pipe = US straight cat > OZ bent cat?

-pete

DaiOni

I'd wager that the US fuel tune could be significantly better than the oz-spec. But I'd still say that it is more than likely detuned from JDM 'high okku'.

It's an interesting question isn't it?

rpm_pwr

There's no doubt the OZspec tune was on the weak side. OZ-spec FD's got a 7000RPM redline. Having driven both, you can feel the difference. The JDM motor sings happily up to the 8000RPM redline. The OZ-spec motor starts to sound/feel harsh up there and the power drops off viciously.

So it's not just ignition timing. Fuel aside the OZ FD engine just physically struggles. Hence the HKS dump pipe I just bought ...

-pete

rpm_pwr

before I forget - If you want to feel the emissions difference on a JDM fd, just pull the airpump connector with the engine cold. The JDM engine will start to pick up a lump idle (sounds like more of a miss) and you will start to feel very dizzy. mmmmm benzene!

Do it on an Oz-spec car and the idle doesnt miss a beat. There's a slight power lump at switch-off (2750 IIRC) and that's it!

-pete

DaiOni

I'm installing an HKS DP this week too. I'm curious to see what the effect will be like, given that the JDM pipe is fairly free-flowing to start with

rpm_pwr

ROFL! I'm assuming you've never seen the two side by side? I wish I kept the stock dump pipe from my old JDM to post here. When you get the stocker off you'll see that you're struggling to get two finger through the bottleneck. With the HKS pipe, the pipe is wider and fattens out at the bend so the cross sectional area doesnt change.

One word of warning though, the stock pipe is generous with the space it leaves. The HKS pipe will let you know straight away how good your engine mounts are. If they're too stuffed, you'll get rubbing as the collar rolls past the pipe at WOT. Been there.

-pete