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-   -   Redlining... (https://www.rx7club.com/1st-generation-specific-1979-1985-18/redlining-248828/)

rotary_neubie 12-05-03 10:03 PM

Redlining...
 
I was once told that redlining a rotary once and awhile is a good thing to do. Understandable.
1st question; anything past 7000 rpm, is there still power being made in a 12a?
2nd question; is it as safer to push a rotary into and past redline than it is to push a non-rotary engine into the same rpm range (compaired to..... for example...... an average honda engine, 6500 redline, approximatly.) Just curious.

Pedestrian X 12-05-03 10:07 PM

Depends, do you have any mods? This under load or in nutral balh blah blah either be more specific or do a search.

faye x7 12-05-03 10:09 PM

Lessee...I don't see how it's good to a push an engine to it's limits every once in a while, but I think the rotary can handle higher RPMs far better than most piston engines.

Pedestrian X 12-05-03 10:14 PM

Redlining once in awhile has been said to blow out excess carbon buildup.. I dont toally disagree but it really depends on how the engien is drivin on a daily basis.

MosesX605 12-05-03 10:19 PM

I think that the general consensus is that stop and go city driving isn't too good for cars in general, whereas steady state highway cruising is ideal. With the rotary, like PedX said, giving the engine a workout by redlining it can blow out that carbon buildup.

Or so the story goes. I'm not really sure, but it makes for a good excuse anyhow. ;)

As for making power past 7000 rpm, with a stockport motor, stock exhaust and a stock carb, the motor is pretty much done making power between 6500 and 7000 rpm, so there really isn't a need to exceed that redline, IMHO.

bizarro 12-05-03 11:23 PM

on a gsl-se its good to at least push it past 4k - 5k within EVERY trip from a - b...this way the secondary ports don't get stuck ;)

cosmicbang 12-05-03 11:42 PM


Originally posted by bizarro
on a gsl-se its good to at least push it past 4k - 5k within EVERY trip from a - b...this way the secondary ports don't get stuck ;)
Them some sticky ports. Driving in glue or what? lol

FD Racer 12-06-03 12:31 AM

I rev my 12a to 8k all the time and try to never exceed 8.5k, but it's streetported...thats were all the power is. On a stock port, going to 7k all the time should be fine if everything is in good working order, especially the fuel system & the OMP. A stock 12a does'nt have more power to be found after 7k.

1984special 12-06-03 05:48 AM

Yeah it seems the GSL-SE really makes more noise than power after 7k... Esp with that annoying redline BUZZER going off in my ear.

It's funny when it scares the bejesus outta my passanger with the buzzer, although the first time I heard it I threw my hands up (not a good idea when redling in any gear btw) in shock! :D

Edit: I think you can avoid most carbon build-up issues by keeping regular RPMs above 2k. I don't know if anyone else does this, but for around town driving I'm always around 2k RPM. Any lower and there really isn't any power to be found. Of course the rotary engine doesn't at all seem to find 2k high, as opossed to a piston, it'd probably be complaining loudly already (except for some honda and really built motors).

rotary_neubie 12-06-03 08:59 AM

I am just curious on which direction to go for mods in the future. A carb, exhaust, and eventually porting, and the car should make higher rpm power, do you loose low end power with these mods? What kinda hp are we looking at with a street port, webber carb, and a rb header with straight thru exhaust? Also does this increase redline ability?

Junia 12-06-03 09:01 AM

I read in a HyperRev magazine for the FD where Ama-san from RE Amemiya said something about Its best to keep the rpm above 2500 when driving around. I figure he knows what he's talking about so thats what I do.

rotary_neubie 12-06-03 09:19 AM


Originally posted by rotary_neubie
I am just curious on which direction to go for mods in the future. A carb, exhaust, and eventually porting, and the car should make higher rpm power, do you loose low end power with these mods? What kinda hp are we looking at with a street port, webber carb, and a rb header with straight thru exhaust? Also does this increase redline ability?

brianw 12-06-03 09:26 AM


Originally posted by MosesX605
I think that the general consensus is that stop and go city driving isn't too good for cars in general, whereas steady state highway cruising is ideal.
I beleive this has been proved to false. Someone correct me fi I'm wrong but I'v heard it said that constant Highway (or steady rpm) is one fo the worst things for an egine.

bizarro 12-06-03 09:33 AM


Originally posted by cosmicbang
Them some sticky ports. Driving in glue or what? lol
its good practice...i've seen people never go over 4k and ports are stuck...carbon just builds up in there and over time just stop working...

hotty 12-06-03 12:29 PM

I was told by.. I thikn peejay, I cant really remember, that you will not damage your Eccentric shaft, as long as you dont rev past 8400, and a few guys with MSD, etc ignition, actually set their rev limiter to 8200, so that when shifting, it doesnt exceed 8400. I can't see why

I beleive this has been proved to false. Someone correct me fi I'm wrong but I'v heard it said that constant Highway (or steady rpm) is one fo the worst things for an egine.
Um, then why would airplanes, in which safety matters the most keep the revs constant almost ALWAYS? I really can't see how constant revs could harm anything more than usual, besides the fact that if it was too high of a constant rpm, eg -> 9000 rpm with no coolant cap on ;)..
Correct me if I am wrong, but I always have believed that highway driving is better than city.

gamble302 12-06-03 02:35 PM


Originally posted by FD Racer
I rev my 12a to 8k all the time and try to never exceed 8.5k, but it's streetported...thats were all the power is. On a stock port, going to 7k all the time should be fine if everything is in good working order, especially the fuel system & the OMP. A stock 12a does'nt have more power to be found after 7k.
same here :D

specRX7_22 12-06-03 10:35 PM

all the SRX7 drivers (stock motors), take the cars up there all the time..... yes there is power at 7, but i dont know about 8.5. The point of revving them so high is that when you shift, youll be right in the main part of the powerband for the next gear.

Pedestrian X 12-06-03 10:58 PM

I think it was that at 8400rpm is when your apex seals start to "chatter". Don't know about the E-shaft. I think highway driving is by far much better for an engine then stop and go traffic. I woudl be really interested to see this report or even hear your opinion on why you think otherwise.

white84 12-06-03 11:33 PM

Rotary revs
 
I'm definately not a mechanic but have had a mechanic tell me that the car should be driven up into the higher revs reguliarly. When I first got the car I used to find myself doing 75 on 4-lane for some extended periods of time (20 miles, just never got shifted, sue me) and suddenly realizde I was in 4th gear. When I asked the mechanic he just laughed and said no problem.:p: Hey the car sounded ok to me.

tomsrotary 12-06-03 11:54 PM

anywhere to 8k on a stock port 12a ain't gonna hurt it.

Sterling 12-07-03 12:23 AM

According to Racing Beat, stationary gears begin to separate at 8400 rpm due to vibration.
I regularly shift at 7K...always less than 7.5 K because I don't trust the tachometer.
The truth is, our tachs are not very accurate to begin with, so trying to approach the highest possible rpm before destruction is probably not a good idea.

I've adjusted the torque on the needle pin on my tach, as well as removed most of the grease. They have a very thick grease on the needle pivot that slows the tach responce so that it does not bounce around.
I did this after installing an aluminum flywheel and noticing that while the engine blipped like a crotch-rocket, there was hardly any change in the tachometers behavoir.
Since then, I've been much more mindful of not hitting 8K. I had also set up a remote pot to control the threshold of the tach buzzer. This is a great thing because I can now set what rpm I want the buzzer to go off.
The buzzer runs off the trailing ignition circuit, and this tells me that the could be set accurately to go off consistantly at a given rpm if a remote timing tach is used to set it.

timmya2 12-07-03 06:47 AM

um guys.. how about for automatics when the only time yur doing considerably high rpms is when yur going over the speed limit..


:(



wat do i do


there this thing u can purchase for it.. i forgot wat its called.. but it makes the car shift higher than normal


PLS TELL ME WAT THIS PART IS CALLED

thanx

inittab 12-07-03 08:20 AM

I notice that my buzzer seems to sound off at different points on the tach gauge. I've always kinda felt the the buzzer was inaccurate but after thinking about it, the buzzer, since it's on a digital circuit, is probably way more precise than the tach.


Originally posted by Sterling
The buzzer runs off the trailing ignition circuit, and this tells me that the could be set accurately to go off consistantly at a given rpm if a remote timing tach is used to set it.
Setting up a remote tach to calibrate the buzzer sounds like a great idea to me. How would one go about doing that? Are there any cheapie digital tachs that can be used?

FD Racer 12-07-03 12:06 PM

I bought a summit rpm activated switch a while back, this one:
http://store.summitracing.com/partde...t=SUM%2D830449

anyhow, when I put it on the 83', set for 8k, the buzzer I had hooked up to it went off right at 8k on the tach...I was impressed. Now when I swapped it over to the 82' on the same settings, it buzzes at about 7500...which tells me that the tach is off. both times it was wired to the trailing.


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