wstrohm

Our '94 now has over 107K miles on its original engine. We just returned from a 540-mile trip, begun with a fresh 4 quarts of Castrol GTX 10W-30 and checked today at about 1/4" down from the original "Full" marking on the dipstick. Coolant was full at start and is still full, both in the reserve tank and at the filler cap. Have never added P/S fluid; brake fluid was changed a couple of years ago, nothing added since. Battery measures 12.65 volts.

The fuel mileage for the trip was 22.31 mpg, which included northbound and southbound ups and downs over the I-5 "Grapevine" (Tejon Pass is at 4144 ft) from sea level. On the long, flat Hwy 99, cruise control was set at an indicated 80 mph for better than 170 miles each way.

It has been my impression from reading this forum that the 13B with 107K miles should by now be low on compression, which I assume would show up in poorer gas mileage. Yet, this most recent result is comparable to the car's fuel mileage when new (we are the original owners).

So, is it going to blow up tomorrow, or what?

portugueserotary

iTrader: (9)

Those are awesome figures! I wish I could say the same about mine! Your best bet is a compression test, I'd love to see how the motors holding up
Steven

Mrmatt3465

iTrader: (10)

Do you premix at all? A compression test is really the best way to tell the health of the motor. This are good numbers. My trip to tail of the dragon was around the same distance and I made about 23 mpg with my cruise at about 75 the whole time. My motor is original as well with 44k

wstrohm

Nope, stock OMP system.

MR_Rick

iTrader: (7)

My second FD had 140K on the original motor when I sold it. The compression was low but not bad. Turbos on the other hand was a different story.

wstrohm

Would be interested in knowing that "different" story!

SA3R

wstrohm,

this pretty much lines up with how my car behaves too (albeit on a lower mileage- 64001 miles) original engine, automatic trans, no premixing etc.
Oil only goes down slightly, about 1/8 inch on dipstick per 1000km. Using Penrite HPR30 20W60 mineral oil.
Compression checked out like a new car when I got it, and it still feels strong.
Never need to top up the power steering pump
Brake fluid has been changed 6 months ago, came out clear, never needs topping up.
Auto trans fluid still clear red, barely ever needs topping up, maybe once in 8 months.
Coolant never ever needs topping up in engine or expansion tank.
Sealed AGM battery, always at full charge, never had hassles with it.
Boosts 10-8-10-8
Coolant temps range from 80C to 100C and never over.

So yes, its not a freak thing. My FD RX-7 is daily driven, and it is THE most reliable car I have ever owned, and the cheapest to maintain & run.
I just filled $30.00 of fuel in the tank (20 litres as a test) and it ran all weekend in city driving with two people, highway, etc, averaging 22.1 mpg and came home still with an 1/8th tank left.
As my fiancee said when I told her about the fuel use "Dont you ever sell this car then!!"

The MOST frustrating part of owning my RX-7 is having to get out of it after driving it all day, locking it up, and just standing there looking at it. Because I love working with my hands. I want at least something to go wrong so I can have an excuse to work on it!! I'm tired of just polishing and cleaning it and walking away unfulfilled. I spend so much time on this forum lately, simply because I dont have anything to do on the car. It is perfect the way it is

ArmitageGVR4

iTrader: (13)

Sounds like you've done things right in terms of maintenance, not messing with your car trying to make 5 jillion horsepower and have also being lucky as well! Keep up the good work

cptpain

iTrader: (1)

This is pretty typical of what happens when someone takes good care in their vehicle and not modifying it to the point where its like maintaining a plane.

gracer7-rx7

iTrader: (16)

Sounds about right. Keep it up.

Tem120

iTrader: (5)

I guess i'm THAT guy .. LOL

but thats awesome i'm glad to hear that ALL these engines dont die at 60k lol

Do you rev it to 8k once a day to keep carbon build up low?

or is it mostly a cruiser?

How would you say your driving habits are

1 being I might as well have a prius ,

and 10 being .. BANG BANG Rev limiter is my home

doctorzaius

Original LIM gasket?

SA3R

I live at 8. I used to drive at 11 when I was younger, but my license couldnt cope
Rev it as far as 7500rpm every other week, but dont make a habit of it. I dont like hearing the limiter. The buzzer is far enough.
I think the worst thing you can do to a rotary is be in 5th (or a high gear for the situation) and just put your foot down, expecting it to pull. Lugging the engine like that seems to be hard on them. Shift down and get the revs up, and its happy

Sgtblue

iTrader: (16)

Compression with a (relatively) high mileage engine was never an issue. At least not with mine. Nor turbos, which are still in the car and going strong. Coolant seals "on the other hand".....

Troclo

Ive owned 2 fd's with aprox 160k on the clocks, one is still fine, the other made 305 hp and tore an apex seal in the end. As long as you keep em stock and drive sensibly the can last a long time. Turbos however usually dont last that long, the secondary turbo sits idle below 3000 rpm and that uncooled waiting time usually gets them in the end.

Tem120

iTrader: (5)

stock rev limiter is at what rpm? I never drove my car on the stock ecu did away with it instantly since my rev limiter is at 8500 , I forgot stock cars had it a bit lower LOL .

but I see give it a run down every other week ok.

arghx

iTrader: (3)

Remember, friction decreases as the engine gets more mileage on it. That's why fuel economy can stay the same or improve on engines (piston or rotary) over time, assuming you don't get a significant loss in sealing.

wstrohm

No. I changed from the burned-out LIM fiber gasket (causing high idle speed) to the later stainless-steel one back at 99213 miles. (Thanks to this forum for the tip!) Compression has never been tested, nor has the boost pattern; sorry for the lack of info.

This is wife's car, bought for her in Sept. '94, usually driven by her except on long trips, when we share driving. I doubt that 8K rpm has ever been seen; but engine is never lugged. Boost is "usually" used, but high revs, no. As "Troclo" mentioned above, the secondary turbo is rarely engaged.

I never intended to imply that this car has always been trouble-free, because it hasn't. Early in its life there were running problems, which turned out to be the original EGR system. Replacing the EGR valve gasket with the later "pinhole model" fixed those problems.

I've posted some previous trials & tribulations here... but consider myself lucky that no extremely expensive disasters have ever occurred. Not as bullet-proof as my '90 Miata, but certainly an "outlier" in the right direction over the last 18 years. The only further "mod" I'm considering is an Efini Y-pipe, but IMHO $650 is a bit much to replace a hose coupling!