Lowest "safe" compression?
#3
Registered
Join Date: Jul 2004
Location: Northern California
Posts: 2,196
Likes: 0
Received 0 Likes
on
0 Posts
Give us some history on your car. What kind of driving did it get, reg or prem gas, short trips to work mostly city or freeway, was it driven hard or never red lined, oil change interval, 5X20wt oil or what, pre-mix used, oil consumption, miles driven, what parts and service has it had, what year, has it ever been flooded, just anything you can tell us....THANKS
#7
Huge hole is huge
If I'm not mistaken, 85 is lingering towards the rebuild number, but it will be fine for another while. I drove on 65 compression for well over a year in my 88 RX-7 Turbo II...and I didn't take it easy on the car, either...
#8
Registered
Thread Starter
#10
Compression figures on a rotary should always have cranking rpm accompanying them and should be comprised of 6 figures (3 front and 3 rear). Low cranking speed will result in low figures.
Paul.
Paul.
#11
Registered
Thread Starter
![Lol](https://www.rx8club.com/images/smilies/lol.gif)
thanks paul, my dealer knows nothing about rotorffies, but they sent it in to mazda, mazda approved of the new engine, so im just going to take the motor
#12
Huge hole is huge
lol a new motor isnt costing me anything, so im just going to do that....if they are offering, why not take it?
thanks paul, my dealer knows nothing about rotorffies, but they sent it in to mazda, mazda approved of the new engine, so im just going to take the motor
![Lol](https://www.rx8club.com/images/smilies/lol.gif)
thanks paul, my dealer knows nothing about rotorffies, but they sent it in to mazda, mazda approved of the new engine, so im just going to take the motor
#13
kevin@rotaryresurrection
iTrader: (3)
Join Date: Feb 2005
Location: east of Knoxville, TN
Posts: 1,415
Likes: 0
Received 57 Likes
on
35 Posts
For the rx8, 96 is the threshold mazda uses for determining if you get a new engine under warranty. However, the engine can continue to run fairly normally well lower than that. I drove my car for about 2 years with 90-92psi and it ran like new...possibly not as powerful as a new model, and started a bit weakly...but ran fine. In the 95 and under range you can start having idle and startup problems, varying from car to car. Rotaries *can* run normally, well into the 85psi range.
#16
kevin@rotaryresurrection
iTrader: (3)
Join Date: Feb 2005
Location: east of Knoxville, TN
Posts: 1,415
Likes: 0
Received 57 Likes
on
35 Posts
In reality most people could be given a 95psi engine and a 110psi engine to drive back to back and feel no significant difference, other than perhaps a slightly faster startup for the stronger engine.
To me there are 3 types of engines. Strong compression tight engines that run well, weak compression engines that still run okay with a bit of a rougher idle, and BLOWN engines that are not streetable because of broken apex seals (zero compression), bad coolant seals (overheats and burns coolant) or bad oil seals (smokes and burns a lot of oil).
Thread
Thread Starter
Forum
Replies
Last Post
gwailo
New Member Forum
38
05-14-2024 06:57 AM
Shankapotamus3
Series I Trouble Shooting
28
03-14-2021 03:53 PM