Ok, so if S2 (or R3 specifically in this case) always read lower, why is that? What is different about them that makes them always read lower?

 

They don't typically read lower, he doesn't know WTF he is talking about.

And the compression standards were changed by Mazda (some say to get out of a number of replacements covered under the extended warranty). And an engine in the 5's @ 250RPM may technically start and run with a good battery and starter but it will run like **** and probably make about 100HP, if that, it sure as hell isn't going to be running without issues.

 

Ok, being as you asked so nicely. That engine is about to fail. There are tonnes of R3s with compression in the 8s. Like this one........can't find any examples......can you? Prove I'm bull shitting Mr. expert. Should be easy for you.

In the meantime;

Rotary Revs - The UK's Premier RX-8 Specialist

Give Ben the manager an email. I once looked at getting a PZ he just rebuilt and ported. It was 8000 miles in, compression 6.9 @ 250 rpm. Nothing wrong with it. I didn't buy it because someone else got there first. Ask him about R3s being lower on average too.

Hurley Rotary - Home

Give Mick the manager an email. He rebuilt my first engine and it tested low 7s after just 8000 miles. He said that's normal and the engine is healthy.

There are more rebuilders but I've never met them personally but they visit the UK owners club forums and say the same thing and sell cars in the low 7s even high 6s all the time with 12 months warranty.

If I'm bull shitting all you need to do is find a few examples of R3s with compression in the 8s.

 

Just keep the insults out of it and present some proof to back up what you're saying. If I'm wrong, I'll admit it but I've owned 3 RX8s and done everything apart from rebuild one myself but I have watched rebuilds being done including my own.

 

Soooo.... because 2 guys at garages in the UK say so.... it must be the Gospel.... were Dyno's done on these "acceptable" rebuilds?

 

Yes I know that.

But, instead of handing out "you're an idiot", I like to understand where they are coming from. In their case, they've been around multiple rebuilds and they understand what compression is....which is in the 95 percentile around here.

I like to lead in the right direction rather than call them stupid.

See how that might be a better use of time?

 

Those 2 'guys at garages' run a team of rebuilders and have been doing it for years. Plus, many others have said this, these are 2 people I have met personally and seen their workshops. They know what they're talking about.


Thanks for being reasonable. As I said, if I'm wrong I'll admit it.
I've said what I believe to be true based off my own experience and advice from reputable experts (not random guys in a garage). If there are lots of examples of R3s (we don't have standard S2s in the UK) with compression in the 8s, they'll be easy enough to find. I can find a few compression tests done on R3s online but all in the 7s or even 6s. Lets just stick to facts and leave the name calling and presumptions out of it.

 

Just makes me wonder if the actual tester is out of calibration, or something like that. Fresh rebuilds should score higher than that.

 

Or they do inferior rebuilds faster, and BS gullible customers into believing it's normal.
Profit.

 

Is it possible you are confusing like the pressure in bar or kg/cm^2 with the compression ratios? That would kinda make sense, but an engine in the low 7s(ratio) isn't gonna be very powerful and will most likely start having issues.

 

Uh-huh.... so what you are saying is that YOU are the authority on this and can verify 100% that those compression results they see are representative across the world.

...Any word on my other question?


This is what I was thinking... "Yeah we're the best, you WON'T get better results ANYWHERE!"

 

Except there won't be though. Even with everyone out saying "Get a rotary compression test before you buy," most people don't. Then you get the compression test when you start noticing problems(hard hot starts for example), and you find out your ratios are in the 7s and 6s.

 

I don't need to ask Ben because he selling you a truck load of bullshit. 8000 miles and 6.9's @250RPM is no way normal or healthy Will it still start, run, and feel normal on the butt dyno? Sure, but it's not magic man, compression numbers are compression numbers (assuming the test was done right that is). Ah rotary revs, the company that just copied the BHR ignition kit rather than come up with their own solution. Actually come to think of it, It sounds about right that they would tell you that an engine with 8000 miles with low compression is healthy.

And it sounds like Mick needs to learn how to rebuild an engine properly, But of course he is going to tell you that is "healthy" rather than admit he did a shitty rebuild.

And the engine is the same in the R3 as in every other 6 speed manual 09+ RX-8 so I don't know why you keep saying R3 specifically. And if my boosted engine is still pumping out high 7's low 8's at 25,000 miles then I can sure you plenty of lower mileage S2 RX-8's are as well.

Like I said, stop spreading bullshit.

 

And as Love Hound said, most owners (especially S2 owners) with well running cars don't go out and hassle with paying for a compression test. Only those that are smart informed people who are looking to buy do, or people who are already having issues with their RX-8.

 

The engineer in me says to confirm your tools and measurement system before jumping to the conclusion that the rebuilds are no good. Is the compression tester working correctly?? Who knows.

You could be passing bad engines as good, or good engines as bad...and not know it.

Proper methods will always lead to the correct answer.

 

^Logic. It has no place here!!!

 

Yea...not on the rx8forum! Lol

 

It also depends on which tester you use and if the results were normalized. We have the Rotary Diagnostics tester here but I borrowed the Twisted Rotors tester and my dealer buddy brought over the Mazda tester so we had a chance to test all three on my car on the same day and the results did vary, and if it were done on a borderline engine, then with one tester it would have been failing while still barely passing on another. So like dyno results, it is good to have as many comparisons as you can before you start interpreting data.

 

yeah, it's a little late in the year to start planting your crops ...

 

Yes..maybe they don't do crappy rebuilds, but have a very pesimistic compression tester.

 

Have any of you had an engine with low compression? I have. It still had it's performance or at least enough for me to not be able to tell a significant difference. Many will say the same. It's just hot starts that become the first problem as it's the metal expanding when you turn the engine off for a few minutes that causes the seals to not make contact. Once the engine is going, performance is not greatly effected like you would think.

Why not just show me a few examples of R3s or S2s with these great readings you keep talking about? I can find a few but all in low 7s or even a high 6. Better than just calling me a bullshitter and making out these rebuilders don't know what they're talking about. I suppose it's easier to call names and make out I don't even know what the correct reading are than provide a bit of evidence to back up what you're saying.

 

Willing to expand that to Series 2 and not just R3?

 

There's no point me going further with this as you're just discrediting the rebuilders and myself with insults rather then showing me examples of S2s or R3s with compression in the 8s.

The only reason I say R3s, as I've said, we only have R3s in the UK. No S2s so I can't comment on them.

Before a potential buyer gets the RX8, they often post compression results online to ask opinions before making the leap. These aren't cars with issues, they're cars for sale. I can find 3 such posts as this one for R3s and all of them are lower than 8s. It might be anecdotal evidence but backed up with what rebuilders say it proves my point so far.

Bring on more insults and your ad hominem arguments.

I'll just keep on eye this thread and see how long the OP takes to find a R3 with compression that you deem worthy (in the 8s).

 

I didn't know you guys only had R3s over there.

Anyway, so we're just going to get all in a tizzy about it rather than investigating the evidence, which is like you said, anecdotal till some more work is done?

When you find a trend like you've seen, you've got to expand and dive further before it can be treated as fact.

 

all r3 rx8s are s2 rx8s. there is no difference in the engine between them and not much difference from the s1 engine (3rd oil nozzle and engine mgmt being the biggest difference). sounds like your "builders" have no clue wtf they are talking about