Someone please settle this!!!
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Someone please settle this!!!
hey everyone i recently saw a ebay listing for a 87 T2 in which the guy said that he recently changed the oil with "fresh new synthetic oil"ive owned over 8 Rx-7's and i know you could possibly run synthetic oil if you remove the oil injection, but this guys system is stock..so i e-mailed him to let him know that he's doing damage to the motor cuz synthetic oil doesnt burn as clean as regular oil.he replied back that he's a mechanic and done his research on the topic..my question is who is right here??
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From: Olympia, WA
He does things different. Is it wrong? No. It's a debated topic, I am actually shocked more that you e-mailed him to tell him he's destroying his engine. Not everyone follows what those on the RX7club says. I bet his engine will last as long as most.
lol, this goes around and around. according to redline, their synth oils burn off fine for our application. other high grade synths claim this too. as for testing, haven't seen any. if you are changing your oil at 3k then there isn't a large enough benefit to justify the extra cost. i can't remember what the ingrsient was, but someone once said something about an ingredient to look for in synth oils that would cause carbon buildup. thats off the back of my head though and could be an acid reflection.
SOLD THE RX-7!
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From: Vancouver, BC, Canada
there are many fights on this...
first in the mazda book it says to not use it. but guess what, oil today is much different then it was 13 years ago. also I've heard that it says that because ONE brand didn't work. they couldn't just say "don't use this brand" in the manual cause then that brand would sue them...
chances are you will blow an apex seal or have other problems well before injecting syth. oil does major damage.. if it does any.
first in the mazda book it says to not use it. but guess what, oil today is much different then it was 13 years ago. also I've heard that it says that because ONE brand didn't work. they couldn't just say "don't use this brand" in the manual cause then that brand would sue them...
chances are you will blow an apex seal or have other problems well before injecting syth. oil does major damage.. if it does any.
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From: Auckland, New Zealand
Originally posted by jeremy
if you are changing your oil at 3k then there isn't a large enough benefit to justify the extra cost.
if you are changing your oil at 3k then there isn't a large enough benefit to justify the extra cost.
The other big advantage of synthetics is their stability under varing temperatures. They stay much closer to the ideal viscosity no matter what the temperature. So they protect the engine better from start-up when mineral oil is very thick and at very high temps when mineral oil starts to thin out.
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thanks everyone for responding..I guess it all comes down to what ever the persons cool with..I guess it was beatin into my head never to use synthetic..I searched this topic and had endless reading..I guess the best bet is to see what type of oil the new rx-8 will be using..
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From: Honaker, VA
I'll change to RedLine here in a week or two. If it helps kill the motor, then I was looking for a good excuse to spend the cash on a street port. If it works really well, then I will find a post to rave about it.
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From: Bergen County, NJ
Rob from Pineapple recommended that I use Mobil 1 synthetic. He says he's been running it for over 100k miles in his 7 with no problems. There's a huge debate, but I was thinking about trying it.
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My 86 n/a I used to own had synthetic put in it all eveytime by the previous owner. I got it with 160,00 miles in top shape. I sold it at 225,000 miles and still going strong.
I personally think its fine with todays syntheticsm but why spend the extra cash when standard oil does just fine.
Good reading on the subject:
http://www.teamfc3s.org/forum/showth...=synthetic+oil
Oh, on a side note, the one and only time I ran synthetic oil in my 88 TII it pulled 2 more lbs of vacuum at idle (and idles smoother). Dont ask me how, but as soon as I switched back, it went back to normal.
I personally think its fine with todays syntheticsm but why spend the extra cash when standard oil does just fine.
Good reading on the subject:
http://www.teamfc3s.org/forum/showth...=synthetic+oil
Oh, on a side note, the one and only time I ran synthetic oil in my 88 TII it pulled 2 more lbs of vacuum at idle (and idles smoother). Dont ask me how, but as soon as I switched back, it went back to normal.
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From: Rohnert Park CA
Originally posted by 1987RX7guy
you can run sunthetic but it will build up carbon and crap since synth burns really bad. He is wrong.
you can run sunthetic but it will build up carbon and crap since synth burns really bad. He is wrong.
do we really need another thread on synths vs reg oils.
as covered in countless threads, and even one this week:
Okay here is the POOP AGAIN on synthetics:
Good quality Synthetics are perfectly fine to use in a normally operating (read still with factory OMP) rotary. The quality ones like Royal Purple, Neo, Redline and Mobil 1 all burn at under 500F with a low low ash (ash is what is left over after it burns) content (in fact lower than many cheaper conventional oils like Havoline, Kendal, Penzoil, etc).
Quality Synthetics as mentioned above are perfectly fine to use after the engine has passed its break in period and will not add or create deposits anymore than a good quart of Castrol.
Lets compare a couple 20W50s real quick:
AMSOIL 36 482 -38 <.5 ---
Castrol GTX 122 440 -15 .85 .12
Red Line 150 503 -49 --- ---
Kendall GT-1 129 390 -25 1.0 .16
Valvoline Syn 146 465 -40 <1.5 .12
Valvoline Tur 140 440 -10 .99 .13
The first number is Viscosity, how well it pours cold at it's temp range (lower the better)
2nd number is Flash, what temp the oils burn at (ideally between 400F to 500F, but not lower than 400F.
3rd number is Pour. Pour is tested 5 degrees F above the point at which a chilled oil shows no movement at the surface for 5 seconds when inclined. Again lower is better.
4th number is Ash. what is left after the oil is burned, again lower numbers are best as high numbers will lead to coking and build up in our engines.
and 5th is Zinc content. Zinc is used as an anti-wear additive, but in too high amounts it can cause build up. .11 is generally considered the highest you need for a 5000 mile drain interval and .13 the highest you need for a 7000 mile drain interval.
You can see just from those numbers that the Synthetics are every bit as good as conventional oil and in some cases better. But they all burn way under the combustion chamber temps found on our cars.
The scary thing is oils like the Kendal GT1 and Valvoline Synthetic, both of which have a high build up potential as well as the Kendal doesn't even meet the 400F min for flash meaning that the oil will break down radically fast in our cars and leave junk behind when it does.
But cheap synthetics (just like the Valvoline above) will leave ash just as bad if not worse than cheap conventional oils (again as mentioned above).
Avoid cheap mixes and cheap oils period!
Now the advantages, it is not unusual to gain about 1%(sometimes 2%) HP increase using a good synthetic (Royal Purple, Neo, Redline and Mobil 1).
Down side, cost! Typically the average Synthetic costs about $35 a half case (enough to change the oil in our cars), vs the $15-$20 a case that Castrol GTX is generally found for. So the quality synthetic is about 3 to 4 times more expensive.
IMO if you have money to burn or you are racing and need that extra 2-3 HP go with the quality Synthetic. Again it is perfectly safe. Just avoid the crappy/cheap ones (like Valvoline, Kendal, Havoline, Etc). But remember just because the bottle says you can go 10K miles on a synthetic you can't. They need to be changed just as often as conventional oils.
But if you are like the rest of us, and money is an issue, then use the Castrol or Penzoil and change your oil reguarlly.
Good quality Synthetics are perfectly fine to use in a normally operating (read still with factory OMP) rotary. The quality ones like Royal Purple, Neo, Redline and Mobil 1 all burn at under 500F with a low low ash (ash is what is left over after it burns) content (in fact lower than many cheaper conventional oils like Havoline, Kendal, Penzoil, etc).
Quality Synthetics as mentioned above are perfectly fine to use after the engine has passed its break in period and will not add or create deposits anymore than a good quart of Castrol.
Lets compare a couple 20W50s real quick:
AMSOIL 36 482 -38 <.5 ---
Castrol GTX 122 440 -15 .85 .12
Red Line 150 503 -49 --- ---
Kendall GT-1 129 390 -25 1.0 .16
Valvoline Syn 146 465 -40 <1.5 .12
Valvoline Tur 140 440 -10 .99 .13
The first number is Viscosity, how well it pours cold at it's temp range (lower the better)
2nd number is Flash, what temp the oils burn at (ideally between 400F to 500F, but not lower than 400F.
3rd number is Pour. Pour is tested 5 degrees F above the point at which a chilled oil shows no movement at the surface for 5 seconds when inclined. Again lower is better.
4th number is Ash. what is left after the oil is burned, again lower numbers are best as high numbers will lead to coking and build up in our engines.
and 5th is Zinc content. Zinc is used as an anti-wear additive, but in too high amounts it can cause build up. .11 is generally considered the highest you need for a 5000 mile drain interval and .13 the highest you need for a 7000 mile drain interval.
You can see just from those numbers that the Synthetics are every bit as good as conventional oil and in some cases better. But they all burn way under the combustion chamber temps found on our cars.
The scary thing is oils like the Kendal GT1 and Valvoline Synthetic, both of which have a high build up potential as well as the Kendal doesn't even meet the 400F min for flash meaning that the oil will break down radically fast in our cars and leave junk behind when it does.
But cheap synthetics (just like the Valvoline above) will leave ash just as bad if not worse than cheap conventional oils (again as mentioned above).
Avoid cheap mixes and cheap oils period!
Now the advantages, it is not unusual to gain about 1%(sometimes 2%) HP increase using a good synthetic (Royal Purple, Neo, Redline and Mobil 1).
Down side, cost! Typically the average Synthetic costs about $35 a half case (enough to change the oil in our cars), vs the $15-$20 a case that Castrol GTX is generally found for. So the quality synthetic is about 3 to 4 times more expensive.
IMO if you have money to burn or you are racing and need that extra 2-3 HP go with the quality Synthetic. Again it is perfectly safe. Just avoid the crappy/cheap ones (like Valvoline, Kendal, Havoline, Etc). But remember just because the bottle says you can go 10K miles on a synthetic you can't. They need to be changed just as often as conventional oils.
But if you are like the rest of us, and money is an issue, then use the Castrol or Penzoil and change your oil reguarlly.
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