RX-8 engine for a Miata?
#1
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RX-8 engine for a Miata?
Just here gauging interest if anyone might be looking for an RX-8's drivetrain with ECU and a 6-speed trans.
Although it's running, I believe my Renesis needs a rebuild. It idles rough but it does revs fine. I have been driving it daily. That said, consider it a core.
Anyone here bent on finding a Renesis to drop into a Miata? I'll be doing an engine swap in my 8 and have the leftovers available. Not sure when. Likely this spring. That's why I'm asking here rather then posting in the forsale section.
Although it's running, I believe my Renesis needs a rebuild. It idles rough but it does revs fine. I have been driving it daily. That said, consider it a core.
Anyone here bent on finding a Renesis to drop into a Miata? I'll be doing an engine swap in my 8 and have the leftovers available. Not sure when. Likely this spring. That's why I'm asking here rather then posting in the forsale section.
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The rx8 engine is a great engine i love the Renaissance motor. All the engines run hard in the autocross have some reliability problems. Many people are blowing up the engines before 100,000 miles. It aparently needs to have a dry sump pump put in it due too oil starvation in cornering.
#7
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The tune on the Renesis is the most unreliable tune Mazda ever put on a Rotary. Blame emissions standards not the engine. Run them on premix and there good to go...except for the horrible gas mileage...and the lack of torque...and the noise...and... well anyway my 8 is getting a v6.
#8
The tune on the Renesis is the most unreliable tune Mazda ever put on a Rotary. Blame emissions standards not the engine. Run them on premix and there good to go...except for the horrible gas mileage...and the lack of torque...and the noise...and... well anyway my 8 is getting a v6.
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Kia and Hyundai are coming out with (or released) some RWD vehicles aren't they? I wonder if the RWD trend of the 80s and 90s is returning. I'm sure it's government crash ratings and other "idiot standards" that are keeping the fun cars off the assembly lines.
#12
Rx 8 problems
The dry sump is for clearance and safety margin and low fitment.
The rx8 renesis's motor puts the exhaust through the side plates instead of through the outside of the eng like previous 13b. This creates alot of extra heat buildup on the side seals. After about 100K miles the side seal springs metal fatigues and looses its spring and collapses. The eng then becomes very hard to start when it is warm. Once started exhaust gases get behind the seal and create enough pressure to seal. If you can find a good replacement spring (they are very thin) that would not collapse due to extreme heat that would solve one of the worst design problems of this otherwise nice , compact, light, high revving eng.
The rx8 renesis's motor puts the exhaust through the side plates instead of through the outside of the eng like previous 13b. This creates alot of extra heat buildup on the side seals. After about 100K miles the side seal springs metal fatigues and looses its spring and collapses. The eng then becomes very hard to start when it is warm. Once started exhaust gases get behind the seal and create enough pressure to seal. If you can find a good replacement spring (they are very thin) that would not collapse due to extreme heat that would solve one of the worst design problems of this otherwise nice , compact, light, high revving eng.
#13
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The dry sump is for clearance and safety margin and low fitment.
The rx8 renesis's motor puts the exhaust through the side plates instead of through the outside of the eng like previous 13b. This creates alot of extra heat buildup on the side seals. After about 100K miles the side seal springs metal fatigues and looses its spring and collapses. The eng then becomes very hard to start when it is warm. Once started exhaust gases get behind the seal and create enough pressure to seal. If you can find a good replacement spring (they are very thin) that would not collapse due to extreme heat that would solve one of the worst design problems of this otherwise nice , compact, light, high revving eng.
The rx8 renesis's motor puts the exhaust through the side plates instead of through the outside of the eng like previous 13b. This creates alot of extra heat buildup on the side seals. After about 100K miles the side seal springs metal fatigues and looses its spring and collapses. The eng then becomes very hard to start when it is warm. Once started exhaust gases get behind the seal and create enough pressure to seal. If you can find a good replacement spring (they are very thin) that would not collapse due to extreme heat that would solve one of the worst design problems of this otherwise nice , compact, light, high revving eng.
So, who wants to buy it?
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That's most likely going to cause the flooding problem. The engine will load up due to cold-start enrichment. The next time you start it you might flood it. Mazda released a firmware update to help the issue. The carbon problem you might have heard about is carbon causing apex seals to stick resulting in loss of compression.
#17
That does help the apex seals run cooler by not passing the hot gasses over the seal. The engine is loud (or use a large heavy exhaust), has **** for torque (aweful in stop and go and local driving conditions), consumes oil by design, it's an inefficient engine (poor mileage), expensive to repair (niche market). They would burn me at the stake if I said that on a rotary forum.
So, who wants to buy it?
So, who wants to buy it?
#18
That's most likely going to cause the flooding problem. The engine will load up due to cold-start enrichment. The next time you start it you might flood it. Mazda released a firmware update to help the issue. The carbon problem you might have heard about is carbon causing apex seals to stick resulting in loss of compression.
#19
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Renesis 13b-msp: 300lb 238hp
Isuzu 6VE1 3.5L: 293lb 260hp
The v6 in question produces >200ft-lb at 1500rpm.
A rotory doesn't offer alot in power to weight. It's a heavy little piggy. You can say that the power to size or power to displacement ratio is better for the rotary but it trades torque for rpm and it's actually pumping 2.6L worth if you want to compare it to a 4cyl. A 4cyl has to turn twice for all it's cylinders to fire once. A rotary fires twice per revolution so in 2 revolutions it's firing 4 times or twice it's displacement. A well tuned 2.6L 4-cyl could easily make 238hp so it's not an amasing feet that this "1.3L" engine makes the same. It's just in a smaller package with fewer moving parts and smoother operation.
If a rotary is showing those symptoms it is likely due for a rebuild. Wow, has it been 20k miles already?
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