rx-7fc

i did about 130-5 in 4th at 7000rpm

13bpower

Do you have all the mods I have? Just because you have 'more' mods dosent mean you have more power. I wouldn't trade one of my performance mods for any other performace mod short of boost.

All the intake and exhaust mods done TOGETHER make a big difference. If you don't have one, the rest that you have done arent nearly as affective.

It seems like most people tend to forget that a upgraded exhaust will not help much if you still have a cat restricting the flow right in front of it!

A full exhaust will not help that much if your intake system is restrictive. Sure the exhaust 'could' get out faster but there is no need for it too if the air can't get into the engine that fast!

Restrictions on reving are the enemy on the rotary. Not the power steering, AC, or some other .5 hp drainer. Not to say these are worthless, but they are over rated.

Alot of people don't drive in 40 degree weather alot. I do. It makes a difference.

All this talk makes me want to take a trip to the dyno an prove some ****, but I am 2 broke.

-steve-

von

BAMBAM ?

Understand something here. At 8000 rpms with my 4.1 gears and 1.00 fourth gear ratio and stock 15 inch tires but 1 inch larger than stock tire I will do 140mph or more in 4th gear at 8000 rpms according to a gear ratio chart I used from a miata forum... Now ad a 1.6% difference or whatever it was and Im around 143.
NOW- The only ? is what RPM am I really at ? Because this can throw off the speedo. Well with my S-AFC wich gives a digital reading I seem to be 400 rpms off in fourth gear at 8000 rpms.

I hit 140 last time at 8100rpms but can easily hit 8300 wich is required for 140mph not including the 3 extra mph that my bigger tires give me.

Ok. I will strap a video cam on my seat and video tape it.
Me and my firends 97 miata will go at it on the freeway and I totally kill him in fourth gear higer rpms. He claims he hits 125-130 but I pass him like no other. Im sure his speedo is very accurate being a newer car.

$150FC

I'd just like to personally thank all of you for re-piquing my interest in my FC - Just as I was starting to worry about power, speed, and cost, you all start spewing out the 8000 rpms and 140mphs... makes my heart warm

That said, anybody have a good engine for an S4 they want to sell? ehehe

The Ace

I really dont get you guys, and I dont really understand all this babling about "140mph" and "150mph" and "top speeds" etc etc....

In my TII, I took it up to 250 (156mph) in 5th, and that was before my catback, filter, rebuilt turbo and TID mod.

I'm guessing I should be a bit faster now

Rxmfn7

iTrader: (4)

Well, I have a K&N cone filter with a cold air box, A RB header, a high-flow cat and a catback with straight through mufflers. I also have mild intake porting, pineapple sleeves, and a reprogrammed ECU. Truthfully a high-flow cat isnt as restrictive as most people think. You probably wouldnt notice a difference between that and a midpipe. The 40* air thing probably makes a big diference though.

RylAssassin

The fastest ive been in my N/A was 120 in forth and i know i could of gone faster but my car felt like it was gonna fly off the ground in a second so i easied off. Call me a ***** but that **** scared the hell outa me i decided not to try a top speed test untill i get my car droped or maybe a wing or somethin

RarestRX

Yo,


The Ace said:

Actually, what I don't get is a Turbo guy coming into a clearly marked NA thread and trying to rain on it. Yeah, we know TII's are faster than NA's. We get it, you guys won't shut up about it. Bully for you that you went 156.

What does that have to do with the topic of the thread? Which gear to use for top NA speed. Your post does nothing except add fuel to the NA vs. Turbo thing. Let us have our own discussion without you trying to start **** about how much faster TII's are.

KS
1989 GTUs "Don't go away mad, just go away."

Rxmfn7

iTrader: (4)

I'd love to race a stock t2....

rotarygod

iTrader: (1)

Gee thanks for the :P bingoboy. I know what the thread is titled. It just became very obvious that turbo people do repond here regardless of title. FWIW my n/a is no longer an n/a but I still have a right to reply :P !

The Ace

Jeez, dont get your panties in a twist. All in good fun....

You do understand that it was just for fun that I posted this, right ? Of course I know that a TII is faster than a N/A , and I also give props to N/A guys just the same.....

Traiko

My FB with RB header, Custom piping, and RB muffler... FPR w/ adequately tuned carb, and finally a bonez intake.... hit 155mph@8k RPMs....

But yeah, I've also been told my fb's body looks like an up-side-down *****... so whatever.

wpgrexx

when i first got my car in stock form loaded up with camping gear i hit 235 km/h at about 6300 rpm in 5th. that was before any mod, unfortunately i haven't made a top speed run since than, don't want to get arrested.

------doesn't top speed relate to gearing, so power wouldn't really affect that much wouldn't it, if the gear is maxxed its maxxed, shouldn't just affect how fast it gets to that top speed? maybe i retarded, never taken a physics course in my life, someone prove me right or wrong please!!!

autocrash

Well... uhmm... yes, and no...
Yes, top speed is related to gearing, but only really in the way gearing limits top speed.
If 5th gear is maxed out, then the car is (gear) limited to that speed.
BUT, one needs the power to max out that gear, and because air resistance increases exponentially with velocity that power becomes increasingly harder to attain. As a result, 5th gear cannot be maxed out without the power to push the car to that speed. Therefore power is important.

(btw, weight doesn't affect top speed... (this is in response to someone elses post) ...just a good thing to remember..)
(weight does affect acceleration though... )

autocrash

(my life is physics... )

blu_gxl

yes, apparently it is!

my top speed is 140 in fifth, in fourth i could get to 130 at about 7500 i run top speed every night going home from school with my friend in a celica GTS.

i bet i could hit 150 there is a LONG down hill section if only i could hit it once when there was no traffic DAMNIT!

Suparslinc

It might have felt light compared to your FD, but my '90 GXL felt solid as a rock as 133mph. Quiet too. only real mod was bonez straight pipe and restored aux. ports.

Now 110 in an FB is something else you feel like your about to get airborne.

I think to answer the original question, even though I don't quite understand the wording, your not going to pull in 5th gear, its just to lug on the hiway with. Top speed in 4th and 5th gear is the same at best; 4th is probably a bit faster.

RX7withNitrous

I hit 137@6,900 rpm's in an automatic 87 GXL.

Jimmy325i

While looking into the location of the 5th gear switch, (I think I might be on to something about the comp cutting out power in 5th) I ran across something else just as interesting in this matter... We have 30% overdrives! What that means is that the engine rpm for the same speed in 4th will be 30% lower in 5th. With such a tall gearing change when you upshift (rather than half of that ratio for other gears) you're immediately placed well below the power band of the motor. I'm assuming mazda did this to keep exhaust temps down as well as emissions at freeways speeds, but this is also the reason none of us has stellar uphill climbing abilities in 5th. The TII's have a slightly shorter 5th gear but not by much. (2% if memory serves me) In compairison to a chevy overdrive ratio of 13-25%, (which is the ratio's for 5th and 6th gears in the vettes) we're getting screwed out of our top speed potential!

Now the real question is what other tranny's can bolt up to a rotary? Even the TII tranny isn't geared low enough in 5th to allow us to see serious top ends (like 170) in a naturally aspirated car.

Rxmfn7

iTrader: (4)

Use FB gears, on a 12A tranny the gear ratios are significantly shorter, especially 5th. Thats my plan, PM Mazdaspeed7 if your interested, he has done it.

Jimmy325i

Is there a thread already out there about this swap? I can get 1st gens for the cost of hauling them away around here. I already have a LSD from a GXL, so the 4.10's are sticking around. (that was also free for the hastle of removing it)

SPZ510

Not even broke in yet, hit 140, stock speedo, shifted at around 9k into 5th and it just held. I'll put in some susp., lower it, and break it in. Looking for 150mph. I dunno about dude who's claiming 155 but I'm guessing his speedo is severly off. Ohh, also plan on 4.30's and making better use of 5th. Wanted 170 but was slapped with reality upon first drive. Looking to go turbo.

KNONFS

iTrader: (14)

Not trying to hack this post, but does your friend's GTS murder your GXL?

BLKTOPTRVL

Around ten years ago I hit 125 (indicated - 5th gear I think) on I-95. I was moving though a gentle right bend in the road at the time and I remember the windows being sucked outward (convertible). That scared me so I backed off. The car never felt light.

I do remember reading someplace that the top end on the 88C was around 128 mph.

RX7_ZRO

I'll let you all know just as soon as I can find an appropriately long enough piece of road in West Virginia that doesn't involve a turn or a hill. 5th just does not like those hills...even at highway speeds (70 mph around here)