Need help choosing an FD
 

I've been looking at an auto, touring FD close to me at a dealership with 98k orig miles. I asked them to do a compression check. This is what they wrote back:


Eric,
We did a compression test on it. Have you ever seen the printout on a rotary engine? It looks like an ekg read out. On a brand new engine the cylinders should read at 6. Our cylinders were 5.5. So they are in great shape. The engine is in great shape it won't blow one week after you buy it.
Let us know if you have any other questions.
Steph Berge
LA Auto


My question and reason for posting this: What the hell do they mean by it reading 5.5 and new is a 6??? I thought compression on a rotary was from 0-140. 140 being brand spankin new? (or was it 0-100?) I'm more than a little scared to buy a car from them when I can't even figure out what they're talking about. Any help from FD experts would be appreciated!

I thought the compression was measured either up to 140 or on a 9.0 scale..... maybe I'm wrong

Read this thread from yesterday:

https://www.rx7club.com/showthread.p...hreadid=273168

It sounds like those numbers are a little low. Also, are you sure you want an automatic?

I wrote them back to question how low the compression is, (5.5). Waiting for their response. That seems pretty low to me, so I'm not so sure it's worth it to buy. I can get it for $10k, but I'm not sure if it's worth it. The auto doesn't bother me too much. I would plan to convert it, but not for a year or so. I'd be happy to drive it this summer as an auto since I wouldn't start playing with the motor til next spring or so.

if you are planning on doing a conversion to manual why dont you just wait and find a manual with a new engine installed.. That would be a better bet for you then deal with the switch.......

Maybe I should mention that I'm an impatient person. Hehehe. Trying to find a manual for a decent price, and in Utah, has been pretty difficult. One more came up for sale yesterday, but I haven't gone to see it yet. I know it's a 5spd R1. Friends of mine know the owner and say he "babies" it. My wallet is limited to $12k, so maybe I'll get lucky with that one since I think this auto would be a big no-no.

No, those compression numbers are fairly low. A new engine will have all the faces on both rotors reading 8.5-9.0 kgf/cm^3, but anything above 7.0 is deemed good compression. There should be six numbers for a compression check, 1 for each face on both rotors. I'd pass on this fd if I were you, unless you feel like replacing the engine soon and converting it to a manual.

5.5 is very low and the motor most likely wont last long because of it. You do realize how much slower automatic rx7s are then manual rx7s right? There is a huge difference. Pass on the car. you can probably find an auto car with a good motor for 10k or better.