Sounds like an air-to-water intercooler is coming. I would love to see the heat exchanger integrated into the hood somehow to keep that stock look. Now that would be sick.
That would be trick! I wonder how hard a chrysler Shaker hood concept would be to make and if it would be a shaker hood scoop still if the rotary only vibrates?
Always wanted to see a belt driven intake manifold on a rotary also. Like, Top FUEL injection hat, massive throttle blades, enormous 10:71 or 18:71 blower Freedom and apex seals for all! I wonder what a Nitro rotary engine sounds like with blower surge? Rob Dahm, please oblige me. Top FUEL 4 rotor INCOMING!! Would be epic
Would be awesome to see if Isaiah could build a custom top mount style intercooler that would be able to flow enough for this turbo. Bigger core and inlets using the original mounts and a made to fit seal to the factory scoop because... why not
Lol won’t work it’s the worst intercooler design period only way for intercooler to work better is better passage of air for cooling this is why sti/wrx guys running more than stock psi use a fmic they are better at cooling a charge n don’t get heat soaked
They make aftermarket top mount inter coolers for the FC. Re Amemiya made one, ARC made one, and a few others. May not find brand new but used for sure. You could also do an air to water cooler in the stock location for a super clean look but more fab work.
The part from @2:45 was just so good. Like sitting in the back seat with two genius tuners while just enjoying the sounds. Thanks for these vids Rob, we really need an hourlong version of that night drive :)
Did the booster vacuum fix also fix the weird MAP signal? If not, double check where your vacuum signal for the MAP is sourced. Back when I was a Microtec dealer and still using Haltec E6K’s on these cars I found that the vacuum ports closest to the throttle plates produced very erratic signals. I surmised it was turbulence near those ports.
I would change out the inter cooler just for a test at least. It’s definitely kneecapping the engine for power. 15:40 yep for sure intercooler can’t handle the flow.
Agreed, I was surprised he decided to use it. it's cool for sure but definitely holding things up. Was it the 3 or 4 rotor that made crazy gains from improving the intercooler? I know this is way less power but Rob seems like the kinda guy who wants maximum efficiency for any set-up.
@@YamahaRider280 4 Rotor. 1st intercooler had a U shaped path. He then changed it to a straight through design after using fluid dynamics analysis to realise the first design was causing a lot of pressure loss.
Might consider mangling the hood some to extend the width and height of the scoop if planning to keep the intercooler at the top, but the large flat hood will probably warp with all the welding. Maybe get the guys that built your fenders for the 4 rotor to build you one from 3d scans of the current hood and just extend the width/height of the scoop to mold in carbon fiber. Plus once they create the mold for the hood, I'm sure others with the same years would like one as well to resell more of them.
I used to have to rely on those quick connect/release air fittings a lot and found if you trim the end of the hose cleanly, push in the fitting firmly and using a flat screwdriver or some side-cutters (while still holding the hose in firmly) pull the locking ring out then pull on the hose to lock it. I usually get an airtight connection 99% of the time, you may get a dodgy fitting or have to trim the hose again.
Maybe get rid of that stock intercooler and convert a new one to an interchiller, put an ac compressor from a prius or something like that and mount a condesor and get an expansion valve and make some custom lines. I think it'd be a sweet build series and I think it'd be the icing on the rx7 cake
He could just modify the stock intercooler to be a water to air if it needs it that bad, running an extra a/c compressor is more load on the engine therefore power loss it just doesn’t make any sense.
@@futurenickel702 research what an interchiller is... the weight of the water, pump, heat exchanger and the limited cooling time frame is way more of a loss than a 1 % power loss from an ac compressor... Also it maintains potentially as cool as freezing temps as long as it's operating with engine running
I literally want to put an interchiller on my fc. Just mounted the water to air cooler and plumbing to run water, plus i still have my ac connected. First i need a better ecu and alternator
It does sound very nice, I think I still like the sound of the four rotor better, just because it sounds like the 787b and thats just the coolest thing ever, though that three rotor is gnarly too, really all of them sound sick.
I am pretty sure the anti surge a little to much anti boost, when he put the straight pipe ic the thing sounds like it has a blow off but it doesn't have, the anti surge hounsing is leaking to much boost I thing
Test your theory. Weld on a larger pipe to the intercooler. Find out if the core is a restriction. If the core isn't a restriction, I still think it would be interesting to convert the factory core to water to air.
I can relate to the brake booster. Had my broken-in motor dyno'd, tuner was like "yep good to go, had her running about 10 minutes ago so it's all up to temp". Thankfully I didn't give it a bootful up the street because as soon as I put my foot on the pedal into a T intersection - rock solid brakes. Pulled up short, turned around and went back, and that little check valve had melted and was a lump of plastic. No vacuum to the booster at all.
That's literally how a surge port works. Its the same way on every surge port turbo. I have no IC and twin 78mm surge port turbos with 3" piping "Y" to 4" piping and 102mm TB. It does the exact same thing. The TB is closed at idle. its going to bypass a TON of air through the port. Larger piping isn't going to change that, Its normal. It will bypass a ton of air at WOT as well. Don't get me wrong, there will be a massive pressure drop across that baby IC, but its not going to screw with your tune as its a constant. I'd look elsewhere. How much of a surge in the boost pressure is there? Could it just be the sensor signal noise? A lot of transducers will make a wavy signal and need "smoothed" in the software. -good luck!
You gotta love inland empire, I was born and raised here and it never rains very often but when it does its always on the days you need it to be dry. lol
I'm about halfway through and what you're seeing is normal. the pulsating in your reading is a smoothing factor in your software. If you have a really good map sensor in a intake manifold and you turned all the smoothing off... you would see the same thing.
That is truly a beautiful car. Opinions ... AN fittings = when its done, it's done. (& Looks cool) Compression fittings = working perfectly for 100+ years Anything else = Fast, which is good because you will get to do it again and again and again.
There's a trick with rubber/silicone stuff where you dip it in isopropyl alcohol to coat the inside where you want the seal. Then when you place it back on and the alcohol dies, it gets really hard to pull off like OEM stuff. I've mainly seen it used on coolant stuff, but it might be worth a try on intercooler plumbing.
Honestly, I never thought I would like an FC. But there is something about white paint and bronze wheels that makes you appreciate this car so much more.
SMC makes some really good push to connect fittings. We use them with helium (helium molecules can leak through smaller cracks than most gases can, we use the helium to test weld integrity) at my job and they perform well. Make sure you are using the right tubing too and double check your temperature ratings on all the above
Use the same principle that the Celica All-Trac/GT-Four did - put a Water to Air cooler in place of the stock intercooler, with a front mounted heat exchanger. It might add a few pounds of weight, but it'll bring your IAT right down and make them a little more consistent.
Rob, Fabdaddy, best way to fix the Vacuum line issue for wastegate is to use with - 3AN or - 4AN Stainless Steel Braided PTFE line, AKA Nitrous line. Easiest way is to find pre-made - 3AN pre-made nitrous lines at Summit/Jegs etc..
it seems like a decent hub dyno would save you a lot of money by saving labor in the shop. I only suggest a hub dyno so you don't have to worry about wheel slip on rollers and tire wear or failure. Also they are really quiet so they can be helpful for diagnostic.
i would love to see the use of top mount do they sell a aftermarket one that can keep up with that turbo?if so heat soak will be a issue still as being in the engine bay so what about a simple intercooler mist system using the factory window sprayers with a mist head on them?even better would be a way to get them to spray at a certain temp or even boost pressure.possaby using AEM water injection but used as a intercooler sprayer this way you can use a tmic setup.just thoughts...
We need Rob to tune my buddies 63 vw bug with a 13b with turbo! Nothing sounds like a rotary, you had boost in your brake lines bro. Check for leaks in the brake system.
I love this shit cause I’ve always wondered how people like Brent from PFI or Jeremy from Fasterproms started tuning and here I am now watching someone learn and progress tuning on a certain platform. Epic
Believe it or not the restriction on the output of the Turbo reduces the load on it, instead of increases. That's why it was spinning faster with the intercooler connected or when you put your hand over the output. Because the air isn't moving out of the way it builds up pressure in the impeller blades, so it spins with the impeller without taking the energy away, reducing the load. That's also why it was blowing back out in a ring around the intake, only so much air can fit in the space, so the rest just get's flung back out. If you've ever plugged the end of a vacuum cleaner you've done the exact reverse, the load drops and the motor spins up because the pressure drops in the impeller. Block the intake or the outlet of an impeller and the load drops because it's not moving air, just spinning it.
I can imagine rob making a new top mount intercooler starting with a core or maybe recycling the 4 rotors’ old intercooler then again would a core that thick fit in that place, anyhow I’m looking forward to seeing how he’ll be solving this problem.
Would be so amazing if Rob could make a detailed video just like the one on wiring but on tuning a rotary. Would be cool to see all the steps it takes to tune it without a dyno.
Ooh buddy I had a 91 RX-7 that looked just like this one... I blew an apex seal, rebuilt it, then blew it up again. I wish I had the funds to build it up reliably like you've been doing.
The thing is surging at idle, what the hell, it will still surge since you have a throttle body And on the second ic setup it was sounding like it had a blow off but it didn't had one. The anti surge is so good it wasn't surging at all without a blow off valve off throttle. Amazing stuff
Man I thought those push lock fittings were the way to go too, but ended up getting rid of all those and going to AN -03 lines due to the same issue you had.
Sounds like an air-to-water intercooler is coming. I would love to see the heat exchanger integrated into the hood somehow to keep that stock look. Now that would be sick.
That would be trick! I wonder how hard a chrysler Shaker hood concept would be to make and if it would be a shaker hood scoop still if the rotary only vibrates?
Yeah if he can do a bigger badder "OEM++" style intercooler that'd be so sick! @Isaiah, make it happen!
@@seanissomething ooooh fack yeah
air water for a build like this would seem weird to me though
Always wanted to see a belt driven intake manifold on a rotary also.
Like, Top FUEL injection hat, massive throttle blades, enormous 10:71 or 18:71 blower
Freedom and apex seals for all!
I wonder what a Nitro rotary engine sounds like with blower surge?
Rob Dahm, please oblige me.
Top FUEL 4 rotor INCOMING!!
Would be epic
Would be awesome to see if Isaiah could build a custom top mount style intercooler that would be able to flow enough for this turbo. Bigger core and inlets using the original mounts and a made to fit seal to the factory scoop because... why not
This!
Lol won’t work it’s the worst intercooler design period only way for intercooler to work better is better passage of air for cooling this is why sti/wrx guys running more than stock psi use a fmic they are better at cooling a charge n don’t get heat soaked
Finally a Rob video! Been too long...
x2
You are not lying!!
X4
Rob got us all jonesing for a fix
YES MORE DAHM CONTENT
for real, the GOAT of non-journalistic automotive youtube content. Never to be beat having set such a high bar.
I hate that BS talking on all of these "journalist" channels. Despite, they bring the very same content for so many years...
Unsubbed to all of them!
MCM exists too
Lmao
They make aftermarket top mount inter coolers for the FC. Re Amemiya made one, ARC made one, and a few others. May not find brand new but used for sure. You could also do an air to water cooler in the stock location for a super clean look but more fab work.
Arc is true jdm goodness but it’s a bit overpriced imo
The part from @2:45 was just so good. Like sitting in the back seat with two genius tuners while just enjoying the sounds. Thanks for these vids Rob, we really need an hourlong version of that night drive :)
Rob needs to buy a dyno. The street tuning is freaking me out.
It’s part of the charm at this point 😂
Actually tuning on the street is far better but of course nowhere near as convenient as doing it on a dyno...
At least this one has headlights
He'll cnc a dyno in an weeks time if he needs it...
He needs to buy a damn trailer
Almost at a million subs rob, hella proud of you bro, you’ve come a long way hopefully you keep making your dreams come true
Did the booster vacuum fix also fix the weird MAP signal? If not, double check where your vacuum signal for the MAP is sourced. Back when I was a Microtec dealer and still using Haltec E6K’s on these cars I found that the vacuum ports closest to the throttle plates produced very erratic signals. I surmised it was turbulence near those ports.
I second this. Cleetus just had this exact issue on his White C7.
@C l a r a__🍒 where do you put your vacuum port at?
@@darrylhaynes9208 lol
i love the FC content! its the most relatable thing to me that has to do with 7's since its actually an FC and not an FD. Please keep it going!
@Rinda Foty what toy do you like a 12a or 13b turbo vibe?
I would change out the inter cooler just for a test at least. It’s definitely kneecapping the engine for power. 15:40 yep for sure intercooler can’t handle the flow.
Agreed, I was surprised he decided to use it. it's cool for sure but definitely holding things up. Was it the 3 or 4 rotor that made crazy gains from improving the intercooler? I know this is way less power but Rob seems like the kinda guy who wants maximum efficiency for any set-up.
@@YamahaRider280 4 Rotor. 1st intercooler had a U shaped path. He then changed it to a straight through design after using fluid dynamics analysis to realise the first design was causing a lot of pressure loss.
Might consider mangling the hood some to extend the width and height of the scoop if planning to keep the intercooler at the top, but the large flat hood will probably warp with all the welding. Maybe get the guys that built your fenders for the 4 rotor to build you one from 3d scans of the current hood and just extend the width/height of the scoop to mold in carbon fiber. Plus once they create the mold for the hood, I'm sure others with the same years would like one as well to resell more of them.
I love watching you with subtitle and when you do a pull, it's says "music"
I used to have to rely on those quick connect/release air fittings a lot and found if you trim the end of the hose cleanly, push in the fitting firmly and using a flat screwdriver or some side-cutters (while still holding the hose in firmly) pull the locking ring out then pull on the hose to lock it. I usually get an airtight connection 99% of the time, you may get a dodgy fitting or have to trim the hose again.
@C l a r a__🍒 Clara likes roteries because they get around.
Maybe get rid of that stock intercooler and convert a new one to an interchiller, put an ac compressor from a prius or something like that and mount a condesor and get an expansion valve and make some custom lines. I think it'd be a sweet build series and I think it'd be the icing on the rx7 cake
He could just modify the stock intercooler to be a water to air if it needs it that bad, running an extra a/c compressor is more load on the engine therefore power loss it just doesn’t make any sense.
@@futurenickel702 research what an interchiller is... the weight of the water, pump, heat exchanger and the limited cooling time frame is way more of a loss than a 1 % power loss from an ac compressor... Also it maintains potentially as cool as freezing temps as long as it's operating with engine running
I literally want to put an interchiller on my fc. Just mounted the water to air cooler and plumbing to run water, plus i still have my ac connected. First i need a better ecu and alternator
I've just done this in my FC.. interchiller with electric AC compressor
@@gflex187 where did you get all the hardware from? And the most important question of them all is, what are you intake temps like?
I love the factory look of the intercooler. Would love to see a larger top mount that has the factory cover.
If you want to stay top mount I'm pretty sure there is a nice one for Subaru's that should work
The FC might just be the nicest sounding car yet on this channel
It does sound very nice, I think I still like the sound of the four rotor better, just because it sounds like the 787b and thats just the coolest thing ever, though that three rotor is gnarly too, really all of them sound sick.
Finally a CZcamsr with sound editing skills!!! Car sounds amazing.
I love your troubleshooting process bro it's so much like IT just with moving parts
I am pretty sure the anti surge a little to much anti boost, when he put the straight pipe ic the thing sounds like it has a blow off but it doesn't have, the anti surge hounsing is leaking to much boost I thing
"Rotaries are a waste of time, but it's my favorite thing to do"
That hit deep.
Test your theory. Weld on a larger pipe to the intercooler. Find out if the core is a restriction. If the core isn't a restriction, I still think it would be interesting to convert the factory core to water to air.
I can relate to the brake booster. Had my broken-in motor dyno'd, tuner was like "yep good to go, had her running about 10 minutes ago so it's all up to temp". Thankfully I didn't give it a bootful up the street because as soon as I put my foot on the pedal into a T intersection - rock solid brakes. Pulled up short, turned around and went back, and that little check valve had melted and was a lump of plastic. No vacuum to the booster at all.
That's literally how a surge port works. Its the same way on every surge port turbo. I have no IC and twin 78mm surge port turbos with 3" piping "Y" to 4" piping and 102mm TB. It does the exact same thing. The TB is closed at idle. its going to bypass a TON of air through the port. Larger piping isn't going to change that, Its normal. It will bypass a ton of air at WOT as well. Don't get me wrong, there will be a massive pressure drop across that baby IC, but its not going to screw with your tune as its a constant. I'd look elsewhere. How much of a surge in the boost pressure is there? Could it just be the sensor signal noise? A lot of transducers will make a wavy signal and need "smoothed" in the software. -good luck!
You gotta love inland empire, I was born and raised here and it never rains very often but when it does its always on the days you need it to be dry. lol
I'm about halfway through and what you're seeing is normal. the pulsating in your reading is a smoothing factor in your software. If you have a really good map sensor in a intake manifold and you turned all the smoothing off... you would see the same thing.
That is truly a beautiful car.
Opinions ...
AN fittings = when its done, it's done. (& Looks cool)
Compression fittings = working perfectly for 100+ years
Anything else = Fast, which is good because you will get to do it again and again and again.
Thanks for taking us through your diagnosis process!
Glad to see you back Dahm. Hope you guys are treating yourselves.
Rob looking professional in that Valvoline coat
And Isaiah in the background 2:13
Loving it
I miss everything about driving a rotary powered car but what I dont miss is the watery eyes from the dam exhaust!!! IYKYK
I check CZcams everyday for a Dahm video even though I have notifications turned on just to make sure I’m not missing anything
Don’t get me wrong, a cammed LS loping is great, but a rotary loping naturally is music to the ears.
I am pretty sure I saw you guys driving this today on my way home from work. I gave you guys the thumbs up in the ralliart wagon
There's a trick with rubber/silicone stuff where you dip it in isopropyl alcohol to coat the inside where you want the seal. Then when you place it back on and the alcohol dies, it gets really hard to pull off like OEM stuff. I've mainly seen it used on coolant stuff, but it might be worth a try on intercooler plumbing.
Reyosuke Takahashi will be proud if you make it look like his FC in the Initial D fifth and final anime series.
Man the sound of an super sequential brings me back and makes me smile
17:25 the turbo sounds like tie fighters from star wars :D
I knew as soon as that stock intercooler went on that was the issue.I was pushing my stock one with under 300 hp.
Honestly, I never thought I would like an FC. But there is something about white paint and bronze wheels that makes you appreciate this car so much more.
SMC makes some really good push to connect fittings. We use them with helium (helium molecules can leak through smaller cracks than most gases can, we use the helium to test weld integrity) at my job and they perform well. Make sure you are using the right tubing too and double check your temperature ratings on all the above
Use the same principle that the Celica All-Trac/GT-Four did - put a Water to Air cooler in place of the stock intercooler, with a front mounted heat exchanger. It might add a few pounds of weight, but it'll bring your IAT right down and make them a little more consistent.
WaZz uP , can't wait till the crazy builds start again . It's kol seeing street rotary's running good with reliability
Keep pushing us videos! We all love them!!!
Rob, Fabdaddy, best way to fix the Vacuum line issue for wastegate is to use with - 3AN or - 4AN Stainless Steel Braided PTFE line, AKA Nitrous line. Easiest way is to find pre-made - 3AN pre-made nitrous lines at Summit/Jegs etc..
Finallllly a video. I was getting withdrawls yesterday and depression at seeing "11 days ago" for the most recent video.
Chill tf out and stop putting pressure on unneeded people. Let rob do his own thing.
I actually cheered when I saw this video. More Dahm content!
it seems like a decent hub dyno would save you a lot of money by saving labor in the shop. I only suggest a hub dyno so you don't have to worry about wheel slip on rollers and tire wear or failure. Also they are really quiet so they can be helpful for diagnostic.
Lmao Isaiah in that back at 2:12
Such a clean car. Awesome content rob. Been a long way from self help videos
New rob dahm video = joy
You posted this as I am setting up the fuel system for my FB
"Rotaries are a waste of time"
-Rob Dahm, 2022
@SO SEXY I'M SEXY do you like roterys or pistons?
i would love to see the use of top mount do they sell a aftermarket one that can keep up with that turbo?if so heat soak will be a issue still as being in the engine bay so what about a simple intercooler mist system using the factory window sprayers with a mist head on them?even better would be a way to get them to spray at a certain temp or even boost pressure.possaby using AEM water injection but used as a intercooler sprayer this way you can use a tmic setup.just thoughts...
Thank you Rob, my fav utuber
We need Rob to tune my buddies 63 vw bug with a 13b with turbo! Nothing sounds like a rotary, you had boost in your brake lines bro. Check for leaks in the brake system.
The RX8 standing there looks mighty fine
Loving the FC content!!! More please
I love this shit cause I’ve always wondered how people like Brent from PFI or Jeremy from Fasterproms started tuning and here I am now watching someone learn and progress tuning on a certain platform. Epic
and this is why im doing stainless steel hard -3an hard lines everywhere in my car for vac line stuff
That bov is mint!
Been (not so) patiently waiting for this
I love that FC
Can’t wait to finish this after the gym
I ran a cheap plastic break booster flap and it broke. Thumbs up for using a an vacuum fitting.
Thats one super cool RX-7, FC's are amazing!
Believe it or not the restriction on the output of the Turbo reduces the load on it, instead of increases. That's why it was spinning faster with the intercooler connected or when you put your hand over the output. Because the air isn't moving out of the way it builds up pressure in the impeller blades, so it spins with the impeller without taking the energy away, reducing the load. That's also why it was blowing back out in a ring around the intake, only so much air can fit in the space, so the rest just get's flung back out.
If you've ever plugged the end of a vacuum cleaner you've done the exact reverse, the load drops and the motor spins up because the pressure drops in the impeller. Block the intake or the outlet of an impeller and the load drops because it's not moving air, just spinning it.
This car sounds so early 200s. Each drive by reminds me of need for speed
Early 200s? They had cars back then?
I can imagine rob making a new top mount intercooler starting with a core or maybe recycling the 4 rotors’ old intercooler then again would a core that thick fit in that place, anyhow I’m looking forward to seeing how he’ll be solving this problem.
Loving the FC videos!!
Would be so amazing if Rob could make a detailed video just like the one on wiring but on tuning a rotary. Would be cool to see all the steps it takes to tune it without a dyno.
I needed this!!
I have those Ecstas on my subaru. Love them.
Damnnn a 10th anniversary FC too? Hell yeah!
Rob out here with them McQueen Vibes
You can switch the tables in the FT to tune in VE like the other ecu’s you refer to.
I was wondering how long it would take you to drop the stock intercooler. Glad you caught it before track day.
Love this project! Like I love all the others.
Man that’s a great looking RX8 in the background!
rob is the absolute expert of butt dyno and road tunes.
i need a UK version of rob
Ooh buddy I had a 91 RX-7 that looked just like this one... I blew an apex seal, rebuilt it, then blew it up again. I wish I had the funds to build it up reliably like you've been doing.
Dahm and a solid car that's something new. 💪
The thing is surging at idle, what the hell, it will still surge since you have a throttle body
And on the second ic setup it was sounding like it had a blow off but it didn't had one. The anti surge is so good it wasn't surging at all without a blow off valve off throttle. Amazing stuff
that turbo sounds insane
I miss that sound! Wish I never sold my turbo II.
Really hope you keep the top mount intercooler but upgrade it. Maybe enlarge the hood opening or something, but please keep it up top!
Tiny intercooler restricts the GIANT TURBO. *surprised Pikachu face*
Also.
Robs clean build loses its hood... *Surprised Pikachu face.*
Love to see if you can 6pack turbo an FA or FB. Just wonder and love to see the power. Plus maybe do a triple compound turbo setup.
Man I thought those push lock fittings were the way to go too, but ended up getting rid of all those and going to AN -03 lines due to the same issue you had.
i wonder if an aftermarket subaru intercooler would work if ya wanted to use the stock hood scoop
Ruby White... Hell Yeah Brother!
"rotary's are a waste of time but, its my favorite thing to do!" Agreed.
Yep, get that front mount IC of even better, do an air to water IC. Will look cleaner and subtract some parts out of the engine bay.
Use the factory hood scoop to feed the turbo cold air.
That was so awesome
Keep it stock, keep it clean and original!
Those wheels look so sharp on the white car.
Hell yeah been waiting for a video to popup
A set of the stock wheels modified by 3 Piece US would looks so good
1 MILL HERE YOU GO