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Thread: Engine mods

  1. #21
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    Chris, I'm really sorry I sidetracked your questions with that legality issue. I didn't mean to cause such a disruption. It really was a sincere question. I can't figure out whether half the stuff that I hear commonly done is legal or not, but I'd like to know. Still wondering.
    Marty Doane
    ITS RX-7 #13 (sold)
    2016 Winnebago Journey (home)

  2. #22
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    Well, according to Steve Eckerich, oil pressure affects the apex seals. So it is clearly not just a longevity issue.
    Grafton
    [/b]
    I missed this one the first time. This is bunk and I'd like an explanation otherwise.
    Chris Ludwig
    GL Lakes Div
    www.ludwigmotorsports.com

  3. #23
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    I missed this one the first time. This is bunk and I'd like an explanation otherwise.
    [/b]
    I'm with you there, I thought I was very clear. Oil pressure=motor lives--period. Some people just hear what they want to hear. I see adjusting oil pressure as no different than adjusting valves. It is just a setting like fuel pressure. I guess every car out there runs stock fuel pressure too?
    Steve Eckerich
    ITS 18 Speedsource RX7
    ITR RX8 (under construction)

  4. #24
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    ***I guess every car out there runs stock fuel pressure too?***

    No, there is a rule .b. p 5 any fuel pump may be used. & an external fuel pressure may be installed.

    Steve, where is the rule that specs that any oil pump or any spring may be used.

  5. #25
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    If you plan to spin it past 7500 look at something other than ferrous metal apex seals. Either carbon or cost-no-object ceramic. [/b]
    Chris, do you have any objective data or seat-of-the-pants comparison between steel and carbon?
    • Starting/idling issues
    • RPM where gains begin
    • Max power/torque gain
    • Usable RPM range
    • Life/durability
    • Ability to conform to used housings
    Thanks,
    Marty Doane
    ITS RX-7 #13 (sold)
    2016 Winnebago Journey (home)

  6. #26
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    ***I guess every car out there runs stock fuel pressure too?***

    No, there is a rule .b. p 5 any fuel pump may be used. & an external fuel pressure may be installed.

    Steve, where is the rule that specs that any oil pump or any spring may be used.
    [/b]
    Nothing personal , but I have seen too many of the rules threads you get into get way out of hand. This is a tech thread for Mazda and you can use the info as you see fit. If you disagee--fine--I will agree to disagree. Just wanted to clear up my first post and the meaning. I was trying to help someone with information--feel free to pick away. Do you think there is a specific rule to allow valve adjustment?
    Steve Eckerich
    ITS 18 Speedsource RX7
    ITR RX8 (under construction)

  7. #27
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    Chris, do you have any objective data or seat-of-the-pants comparison between steel and carbon?
    • Starting/idling issues
    • RPM where gains begin
    • Max power/torque gain
    • Usable RPM range
    • Life/durability
    • Ability to conform to used housings
    Thanks,
    [/b]

    In my experience...

    Carbon don't start as well cold. They require a shot of ether in the morning. After that they're golden for the day. The carbon seals require a bit more clearance than a stock type seal and I'm guessing that's where the cold starting becomes an issue. They also don't run quite a spring pressure as a steel seal so there again cranking compression suffers. Idle is same as anything else.

    I'm not so sure you're going to see an big gain in power over stock seals within the powerband of an IT engine. The gains will be near the power peak and above. The reason I like them is because they are much easier on the rotor housings. Iron seals start to skip across the housing north of 7k. After some miles you'll actually be able to see lines running perpendicularly across the surface of the housing where the seals are skipping. This a) causes a loss of power because of blow by, and eventually ruins an otherwise good housing. So there is a possibility for a slight gain but it's in an area where the power has already peaked and is begining to fall off. Now if you're shifting passed the power peak (say 8500) to optimize average HP then the carbon seals will be an asset in longevity and provide a slight power bump.

    Comparing a dyno chart that we have on one of our carbon sealed engines with a dyno chart supplied by a customer on a iron sealed engine we're showing about 4-6lb/ft advantage from 5k+. Though that, IMO, is within the realm of dyno calibration and any of a multitude of differences in the cars themself.

    Carbon seals have spun over 10k. No issues with an IT engine. The word on the stock seals is 8500. I think that's optimistic. The Renesis spins to 9k but those seals are about half the height (half the weight...) of a Cosmo seal. There is also not an exhaust port for the Renesis seal to skip across.

    There is a guy on nopistons who used to campaign a GT3 RX-7. He's reused his set of carbon seals in several engines. That said, I'm not that thrifty and would opt for new seals if I were building a new engine. The set that came out of my last IT engine when I tore it down after two years measured out at as-new height. I gave them to a friend and we put them in his j-bridge engine. The real deal plus is rotor housing life. Not only are the carbon seals easier on the surface in general they are one piece. The lack of the corner assist piece that likes to dig a groove around the circumference of the housing is a plus. Rotor housings, the real expensive part, should last longer.

    Not really sure on their ability to conform with used housings. You really should up for new anyway.
    Chris Ludwig
    GL Lakes Div
    www.ludwigmotorsports.com

  8. #28
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    Nothing personal, but you Steve are the typical person who likes to to think he has a grip on everything but don't want to acknowledge written rules.

    I ask you where is the rule that specs that any oil pump or any spring may be used (If you can't identify a rule then there must be no rule.) & you don't answer the question about the rule, you stary the thread by talking about valves. Within this thread conversation about modifications to an ITS rotary motor in comes the written rules which make the modifications legal or illegal.

    ***Do you think there is a specific rule to allow valve adjustment?***

    Your darn correct there is a rule about adjusting valves. (Don't blame me for straying the thread.) If the rule ain't writte under .D. Authorized Modifications ya set the valves to the factory workshop manual specifications.


    ps: Chris Wire, sorry for messing with your thread but this free lance stuff IMHJ needs to go.

  9. #29
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    I think there may be some confusion on the oil pump vs. oil pickup wording - especially if they are one integral piece. I will get a clarification from Topeka.

    AB

    Andy Bettencourt
    New England Region 188967

  10. #30
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    Nothing personal, but you Steve are the typical person who likes to to think he has a grip on everything but don't want to acknowledge written rules.

    I ask you where is the rule that specs that any oil pump or any spring may be used (If you can't identify a rule then there must be no rule.) & you don't answer the question about the rule, you stary the thread by talking about valves. Within this thread conversation about modifications to an ITS rotary motor in comes the written rules which make the modifications legal or illegal.

    ***Do you think there is a specific rule to allow valve adjustment?***

    Your darn correct there is a rule about adjusting valves. (Don't blame me for straying the thread.) If the rule ain't writte under .D. Authorized Modifications ya set the valves to the factory workshop manual specifications.
    ps: Chris Wire, sorry for messing with your thread but this free lance stuff IMHJ needs to go.
    [/b]
    I can live with that assumption. So by your interpretation I can adjust my oil pressure to 78 PSI @ 3000 rpm like my FSM says I can--right? Mine is right on the money so yes, I think I am Legal. I never said anything about different pumps being legal--just pressure.
    Steve Eckerich
    ITS 18 Speedsource RX7
    ITR RX8 (under construction)

  11. #31
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    I can live with that assumption. So by your interpretation I can adjust my oil pressure to 78 PSI @ 3000 rpm like my FSM says I can--right? Mine is right on the money so yes, I think I am Legal. I never said anything about different pumps being legal--just pressure.
    [/b]

    A GCR is inlcuded with our licenses now...

    See: 17.1.4.D.p

    "All engine components not otherwise listed in these rules shall meet factory specifications for stock parts..."

    There isn't much room for interpretation here. The parts must be stock, AND anything ajustable (not mentioned elsewhere in the ITCS) must meet factory specs.

  12. #32
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    Ok, just to take this to the logical conclusions. here's where we stand.

    A- IF the pump is integral with the pickup, it could be changed to another under the free pickup clause, according to Andy.

    B- If it is NOT integral, then the parts within must be stock to an engine on the spec line.

    So, if B is the case, SHOULD the rules be ammended to include the phrase "pressure relief spring", to allow higher oil pressure more suitable for racing?

    It does appear that the rulemakers felt that better oiling was an important aspect of the IT build, and wrote rules to make allowances for that.
    Jake Gulick


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  13. #33
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    It does appear that the rulemakers felt that better oiling was an important aspect of the IT build, and wrote rules to make allowances for that.
    [/b]
    I think that the rule allowing alternate oil pickups was to accomodate the legally-used oil pans that may have a different pickup than a stock pan. I pretty much read the rule the same as Grafton and will adjust accordingly.

    Sorry for blowing kerosene on a match!
    Chris Wire
    Team Wire Racing ITS #35

    www.themotorsportshour.com
    "Road Racing on the Radio"
    WPRK 91.5 FM
    wprkdj.org

    "Tolerance is the last virtue of a degenerating society" - Unknown


  14. #34
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    ***So by your interpretation I can adjust my oil pressure to 78 PSI @ 3000 rpm like my FSM says I can--right? ***

    Steve, naw ya can't adjust the oil pressure control valve because the factory workshop manual gives you no instructions to adjust the oil pressure control valve. The factory workshop manual instructs you to buy a new spring & or plunger if not within specifications.


    ***So, if B is the case, SHOULD the rules be ammended to include the phrase "pressure relief spring", to allow higher oil pressure more suitable for racing?

    It does appear that the rulemakers felt that better oiling was an important aspect of the IT build, and wrote rules to make allowances for that.***

    Jake, that would be your take on the current written rule .h. My take on the curent written rule .h. would be that the rules writters wanted to allow one to be sure there was an ample oil supply present to be picked up & to allow one to remove oil to eliminate wasting hp.

    Those who are having fun please continue

  15. #35
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    I think there may be some confusion on the oil pump vs. oil pickup wording - especially if they are one integral piece. I will get a clarification from Topeka.

    AB
    [/b]
    Not sure how that's relevant here. The 13B oil pump is a separate part from the oil pickup (assuming by pickup you mean the tube and screen).
    Marty Doane
    ITS RX-7 #13 (sold)
    2016 Winnebago Journey (home)

  16. #36
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    Just talking in generalities, not rotories specifically. WIll ask Jeremy his thoughts.
    Andy Bettencourt
    New England Region 188967

  17. #37
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    Here's a topic for the original poster.

    If you replace the oil pellet deal behind the front pulley, then do it when the engine is out and on its back. (Front of the engine pointing straight up at the sky.)

    I replaced one of those things while very closely following directions while it was still in the car and it got in there incorrectly and ate my engine eventually.

    If you have the engine out, put the pellet in there by dropping it straight down. That way the bearing behind it doesn't slip and you're engine will continue to oil correctly.

    Use an underdrive pulley. Actually two of them, for the main pulley and for the alternator.

    From what I learned from talking to folks, you don't really need a turbo oil pump. You just need to shim the regulator. Which I did and it seems to work ok. Even with the extra factory oil cooler, which lessens the oil pressure. I would REALLY recommend a second factory oil cooler, btw. I just couldn't get my car to stay at reasonable temperatures without one. I also fitted a big electric fan so that it won't overheat when I come off the track and putt around the pits.

    Also you can throw out all of the emission controls, but make sure that what's left doesn't leak and is in working order. Vacuum leaks are common on these things. Make sure all of the vacuum stubs are blocked off behind the manifold, too.

    Get a real oil and water temperature gauge. The factory stuff is useless for keeping your engine alive.

    You probably know most of this, but I figured I would post it just in case.



    -----------
    '89 RX-7 ITS

  18. #38
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    Here's a topic for the original poster.

    If you replace the oil pellet deal behind the front pulley, then do it when the engine is out and on its back. (Front of the engine pointing straight up at the sky.)

    I replaced one of those things while very closely following directions while it was still in the car and it got in there incorrectly and ate my engine eventually.

    If you have the engine out, put the pellet in there by dropping it straight down. That way the bearing behind it doesn't slip and you're engine will continue to oil correctly.[/b]
    Got it, engine's out, will act accordingly.

    Use an underdrive pulley. Actually two of them, for the main pulley and for the alternator.[/b]
    Got 'em already

    From what I learned from talking to folks, you don't really need a turbo oil pump. You just need to shim the regulator. Which I did and it seems to work ok. Even with the extra factory oil cooler, which lessens the oil pressure. I would REALLY recommend a second factory oil cooler, btw. I just couldn't get my car to stay at reasonable temperatures without one. I also fitted a big electric fan so that it won't overheat when I come off the track and putt around the pits.[/b]
    I actually have a very large Fluidyne oil-to-air cooler that will sit where the factory cooler goes. It is used by others here in SEDiv and seems to work well. The key seems to be placement in the airflow, and sealing up the nose via splitter and undertray (back to the rear edge of the front bumper, of course!)


    Also you can throw out all of the emission controls, but make sure that what's left doesn't leak and is in working order. Vacuum leaks are common on these things. Make sure all of the vacuum stubs are blocked off behind the manifold, too.

    Get a real oil and water temperature gauge. The factory stuff is useless for keeping your engine alive.

    You probably know most of this, but I figured I would post it just in case.
    [/b]
    Thanks Scooter.
    Chris Wire
    Team Wire Racing ITS #35

    www.themotorsportshour.com
    "Road Racing on the Radio"
    WPRK 91.5 FM
    wprkdj.org

    "Tolerance is the last virtue of a degenerating society" - Unknown


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