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Rick, run the Evans NPG+ with a zero pressure flat cap, that's the whole point. We're not reinventing the wheel here guys-- turbo rotary owners have been running Evans NPG+ for decades. On the street, on the road course, even on the Tail of the Dragon. Zero pressure cap, OEM overflow and all functions as you'd expect. Guys with stock twin turbo systems too believe it or not (to include "all the little hoses and warm up system and sensors") and again all functions properly. Theory is great but without real world experience I'd say it's best not to make recommendations to other people on their setups.
For those reading and may have missed it--- appears Ben/Rotary Extreme went with different pressure caps as a bandaid for an engine with a failed coolant seal. Not something that any of us should hopefully have to deal with
This right here. ^^
I've been running pressure less on multiple vehicles for 20+ years. I've also had a blown coolant seal blow coolant out of my overflow tank with a factory full pressure cap and standard coolant. If your engine is in good running order and your cooling system is in good shape, you should have no problems running pressure less. You will see more of a swing in overflow tank volume (or not since you can't see the physical tank in an FD well) which comes with natural expansion and contraction of the heated/cooled fluid. With a pressure cap you will see less because it has to make it past that pressure barrier to expand into the overflow bottle. As long as you have no holes in your system for air to be sucked back into while cooling down, your overflow bottle will still work like factory, fill a little when hot, then the system will suck it back down when it cools off. This will happen as long as that overflow tank is the only point of exposure to the atmosphere. The coolant circulation will not push anything out of the tank. On one of my Daily Drivers, I've driven from Florida to Utah and back, from Sea Level to 12,000+ ft in the Mountains of Colorado with a pressure less system that had already been running in the car for 4+ years and had no issues.
I plan to do a video of my Conversion on my stock twin car hopefully this winter after I acquire all my cooling system restoration parts to help people in the future with a lot of these questions and functionality.
Back to the build, The Dash looks great, I'm a big carbon fan and there's no reason why you can't mix functionality with clean looks, especially in an FD. I hate to see when FD's are turned into track cars the interior has been completely removed, boxy and pretty much unrecognizable as an FD while sitting in it. Everything is Driver Centric from Factory and flows so well, no point in removing that aspect from the vehicle if you don't have to.
Theory is great but without real world experience I'd say it's best not to make recommendations to other people on their setups.
I can't agree with you any more on the above statement - thank you for the feedback Rich
I will always caveat my theories (and even outcomes and experiences for considerations on variables) to be taken with a grain of salt
Thanks for another thorough write up here @boostin13b
That road trip must have been a lot of fun
Your videos are well done, ring true as rotary enthusiast authentic, entertaining and funny with the video cut ins - keep up the great work!
Looking forward to an installment on waterless conversion
Thanks for the compliment on the dash - form (even if just in the peripheral vision) and function is the exact modus operandi I have sought over the decades
.
I have that dash template (created in excel finalized by my GD Wife in illustrator) in a ready for vinyl print out vector format - PM me if interested
Lined up for a quieter first tuning session on the dyno with Renna today, getting us into the ballpark before we make some noise
Ihor tore down and built the brand new motor up for 600+whp, EFR 8374 and shorty manifold may be our restriction "limiting us" to high 4's
I'll be happy with a responsive 400 for the long run
Rick, run the Evans NPG+ with a zero pressure flat cap, that's the whole point. We're not reinventing the wheel here guys-- turbo rotary owners have been running Evans NPG+ for decades. On the street, on the road course, even on the Tail of the Dragon. Zero pressure cap, OEM overflow and all functions as you'd expect. Guys with stock twin turbo systems too believe it or not (to include "all the little hoses and warm up system and sensors") and again all functions properly. Theory is great but without real world experience I'd say it's best not to make recommendations to other people on their setups.
For those reading and may have missed it--- appears Ben/Rotary Extreme went with different pressure caps as a bandaid for an engine with a failed coolant seal. Not something that any of us should hopefully have to deal with
Well, I can't argue with real world experience - I mean there's many ways to skin a cat. I did run zero pressure and it pushed everything into the reservoir and couldn't suck it back. About theory and recommendations, maybe I should have just said run it like the engineers designed it to - with a pressurized cap. (also real world experience). hahahaha 😜.
But I get it, the pressurized cap is to prevent the water from turning into steam in a normal coolant mixture (not an issue for Evans), but the system will benefit from some pressure to assist flow into off shoots.
I personally will still use the pressurized cap, but I'm running the Ford specialty green coolant now. It feels like it has some lubricating property in it. Recommended by Mo from Palm Tree Rotary.
Im still surprised at how my engine has been holding up.
It sat for 3 months and I had to add 1.5 gallons of coolant due to the leak, car still fired up.
If you guys ever have to deal with this situation until you can fix your engine, heres what I do.
1. I check the coolant level while the car is cold and add until its full. I also added a drain tube with a valve to the coolant reservoir, I drain the coolant that does not get sucked back in into a bucket and throw it back in the engine.(because my engine pressurization issue)
2. I have the fuel pump battery relay mod, I pull the plug off the relay and crank the engine a few times to try and get what ever out that's sitting in the engine.
3. Plug the fuel pump back in and continue to start the car. Might take a few cycles but it always starts.
4. After a drive around the block checking new FC Tweak settings, I turn off the car and immediately open the coolant pressure lever on the cap and let it escape to the reservoir. This greatly reduces the amount of coolant under pressure to seep past the bad orings back into the engine.
Can't wait to see this thing back on the track. Such an awesome build.
Last edited by rotaryextreme; Aug 21, 2024 at 08:37 AM.
I've been running pressure less on multiple vehicles for 20+ years. I've also had a blown coolant seal blow coolant out of my overflow tank with a factory full pressure cap and standard coolant. If your engine is in good running order and your cooling system is in good shape, you should have no problems running pressure less. You will see more of a swing in overflow tank volume (or not since you can't see the physical tank in an FD well) which comes with natural expansion and contraction of the heated/cooled fluid. With a pressure cap you will see less because it has to make it past that pressure barrier to expand into the overflow bottle. As long as you have no holes in your system for air to be sucked back into while cooling down, your overflow bottle will still work like factory, fill a little when hot, then the system will suck it back down when it cools off. This will happen as long as that overflow tank is the only point of exposure to the atmosphere. The coolant circulation will not push anything out of the tank. On one of my Daily Drivers, I've driven from Florida to Utah and back, from Sea Level to 12,000+ ft in the Mountains of Colorado with a pressure less system that had already been running in the car for 4+ years and had no issues.
I plan to do a video of my Conversion on my stock twin car hopefully this winter after I acquire all my cooling system restoration parts to help people in the future with a lot of these questions and functionality.
I'm all for a better system.
Car engineered with emissions, but runs better without it.
50/50 coolant and pressure cap to reduce boiling - evans addresses that
Im just curious while driving when the fluid expands and goes through the nipple by the cap, through the hose and down to the reservoir - how does it get sucked back in at the same rate as when it exits during high rpm. Just one air bubble on the reservoir hose side can break the fluid chain. I think there has to be more to it. I know my car has a internal coolant leak but during my test with no pressure cap it forced out a gallon through that nipple. Flow, thermal expansion, whatever you want to call it. But the system was unable to suck it back in because either the fluid dropped to fast or whatever.
So guys please educate me because I really want to know, with zero pressure and with the reservoir in play how does the system not push fluid out that port during acceleration and.... how is it sucked back in when you lift off the throttle without assistance of a pump in the reservoir. The assisted flow into the reservoir will out flow the unassisted fluid being able to get sucked back into the engine. I just cant imaging this being ideal in a drift or track or togue situation.
I read "real world experience" but can we have a better explanation other then it works?. I need little kid language to help me visualize this - please.
I was contemplating pressure-less on my build as well, and this is an interesting discussion. My motor is a semi p-port with epoxy'd water jackets, not really the modern way of doing it (I know), but the motor is already built (by a reputable builder) so I'm going to run it. I thought perhaps the pressure-less coolant would be easier on the epoxy without pressure forcing water past it.
I did pop back into AiM RaceStudio on my old laptop with an older version (outdated v3 3.16.22) previously synced to my dash (new laptop new version hasn't been synced up yet)
Some throwback pictures from when I first fired it up
This time around I mostly putzed around the shift light set up
This will need fine tuning once we set up boost by gear gleaned from my power band
I will revisit the page set ups again later
I will need to fully set the dash up once I can reconnect to it, and see what has been provisioned already and what's coming over from the ECU
Thank you all for the compliments and condolences
Last edited by ZumSpeedRX-7; Aug 21, 2024 at 05:25 PM.
Some minor updates to catch up as we get closer to the finish line
Dyno session two had some more issues keeping us from putting down power
Good news, initial resolve IWG75 wastegate holding issues with the 10psi springs
Fuel map still wasn't responding right. VE map was very high compared to Renna's expectations. Did some experimenting with adjusting dead times / flow up and down to see if it made a difference.
Primary is reading like a 715cc injector (it is a 1050 so that's not right...)
We pulled them to send out to Injector Dynamics for a flow test
Looked brand new to me, but strange things happen
...Flow test approximate expectations for 1050s/2000s
Good news! But then what?
Some other minor things we're changing in the tune are moving off distilled water to ~35% methanal washer fluid
I will be stocking up on this stuff like an Alaskan ice road trucker
Next theory is MAP sensor. We tried 3 different calibrations for my GM sensor, closest got to show 0.6psi with the car off
Injectors should be back over the next few days to test
Other minor details scoped when I thought this was going to be a quick turnaround
Wrapped up the keys - fear of my skewed OEM snapping off resolved
Wrapped up with brand new driver side door handle (sadly that buttery smooth RE Amemiya shifter shipped out to Nader with my Series 8 transmission - still holding out for a C's, Mazdaspeed, JP3 or... Costa's Stillway 0-400 permanently locked out?)
I will throw my brand new passenger handle on in my own garage
Blast from the past picture of me cruising down to NY Rotorfest 2006 - I should have replaced this handle a long time ago
Last edited by ZumSpeedRX-7; Oct 15, 2024 at 03:09 PM.
Reason: test result flow charts
Couldn't bring over the factory hazard button as though, but Kris had a solution
Punchlist - check!
Took a while from concept to execution, but the HVAC panel is done!
Blender door and heater valve have been pinned for the HVAC switch - fingers crossed for full bore hot air at the windshield after we start her up with the injectors
Spoke with Elliot @Turblown and Ihor this morning, and this one was a no brainer for a dropship since the UIM was off for the injectors and we have Renna lined up
Fingers crossed we clear the under UIM coils and flex fuel sensor
We'll see - I think +5-10% over OEM UIM is worth some minor changes
Ordered and delivered all in under 48 hours - thanks Elliot
A beautiful piece
Ihor vapor honed it and gave it an initial test fit
Unfortunately it doesn't clear the under UIM smart coil mount, and how we have my Turbosmart FPR mounted
Not an exact comparison, but OEM for visual approximation
The LPS AlphaLoc couplers have zero play or wiggle room like I'd get easily with silicone or the play I'd get with a VanJen
The rear wheel horsepower on this piece is too good of a return on investment to give up easily
But rationality is necessary - if the intercooler piping is misaligned with the smart coils removed, this may need too much rework for this build iteration
Back up plan, I can live with boxing it up for now and wrapping it up with the new Turblown 90* elbow, new intercooler piping, and retune down the road
Adjustment of the turbo compressor cover and BOOM!
Not fully out of the woods on this one yet - need to move the FPR, coils, slot IC mounting bracket holes, and sort oil cap clearance - but it's looking promising
Thanks Elliot for the extra bump to see it through and Ihor for making it happen
Got the chance to drive Nak's 6266 FD - awesome build! John's modified Z06 is a beauty too and damn does it sound good
Originally Posted by ZumSpeedRX-7
Not fully out of the woods on this one yet - need to move the FPR, coils, slot IC mounting bracket holes, and sort oil cap clearance - but it's looking promising
✓ I think we're there
Getting fitted for drop in
Fuel lines re-routed with a new FPR bracket
Elliot dropshipped new IGN1A smart coil brackets with hardware and MSD 8.5mm super conductors
Oil cap clears the intercooler piping
Going to replace the faded pink FEED cap with a brand new one I have in the basement, and will shave the sides of the faded one for better clearance and refinish
Back in business
Still keeping my eye on clearance with the AutoExe strut tower bar
Fired back up and reset the MAP settings (switched off GM 3bar external to Elite 2500 internal) and IAT (new fast-response resized for the UIM)
Heading down to the shop next Friday for another dyno tuning session with Renna
Probably have to cut and reweld that one section on the Autoexe strut tower bar, looks awfully close to that LPS coupler. Is your engine in the OEM height( IE stock oil pan, stock motor mount ? )
Is your engine in the OEM height( IE stock oil pan, stock motor mount ? )
Of course not - now why would I make any single piece of this easier for myself?!
Stock oil pan (for now - brand new, came with the engine) with IRP brace, and Full Function Engineering 85A engine mounts
I have found a few strut tower shim options that will free up some extra clearance, but the strut tower scaffolding will be one of the last things to go on
Reshuffled my hoarders nerd edition book shelf a bit
Found some cool features - made cleaning up a little less efficient but a lot more fun
Lieutenant Commander Carlos Iglesias feature in RX Tuner - happy Veterans Day my friend
Dan McVicker's beautiful build. Had the joy of chasing Clunkers with a little cat and mouse all day out at Monticello Motorsports Club - there will be more track days like this soon!
and Rich Farrell's all the best things build - happy Veterans Day
and this green RE Amemiya AD Facer 9 RX-7 was one of the first builds I tripped over when I had my Integra GSR that made me fall in love with the FD (circa 2000 / 2001) - still one of my all time favorites to this day
A buyer's guide from a few month's before I bought my FD in May of 2003
My FD was just over $17,000 - fresh remanufactured motor and brand new twin turbos on a '93 Touring, price was in the "excellent" ballpark
I am still not done with this yet and am trying to pitch my wife on the idea of getting a few magazine racks for the basement
Brought the Xero RS back in for my annual Bride physical
finalized by my GD Wife in illustrator) in a ready for vinyl print out vector format - PM me if interested
