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diabolical1 04-28-08 07:31 PM


Originally Posted by rxforspeed (Post 8092487)
I have recently received a 6lb aluminum flywheel and the counterweights needed to install it, ...

off topic for fuel, but which flywheel is that?

as far as your fuel system is concerned, it sounds like it's being overbuilt ... which sounds just about perfect to me. :D

rxforspeed 04-29-08 08:58 AM

Diabolical, I tend to take my projects to the extreme and the fuel system in my car is no exception. Overkill may be an understatement-I don't even plan to have 300HP with the turbo 6-port (shooting for more low-end torque, hence the T04E). It'll be carb'ed for a few months or so until I can afford all my EFI equipment (I think I'll have to go MegaSquirt-I don't have a great job anymore to afford the Haltech I was wanting), but I still don't think I'll hit the 300HP mark even with a properly tuned EFI system. I'd like to see gobs of torque when the turbo spools though...

If it's worth doing, it's worth doing right. You never know, I might acquire an S5 TII engine and crave 400+HP in the future, so I know my fuel delivery system will be adequate if and when that time comes...

About the flywheel-I thought it was a RB unit but I don't believe it is. There's some logo on the disc side that has an eagle on it (I forget the name now), but I got it in pretty crappy condition. I had it resurfaced and the flywheel itself appears to useable now (despite minor wear on the ring gear), but I'm unsure if the counterweights are for an SE 13b. There's an additional hole drilled in the front counterweight and I don't have another rear to compare it to. BTW-I'm comparing my stock manual front counterweight to the one received with the flywheel-the automatic-equipped vehicles may differ, but I don't know since I've never had an auto SE 13b engine to compare with mine...

I still have to figure out how I'm going to remove the dowel pin in the rear counterweight because it's just FUBAR'ed. I'll worry more about it if I don't have it out by the time I find a good clutch designed to handle 250-lbft of torque. I'll post pics here soon (in the next few days) and show you what I'm referring to.

Here's the link to the thread where I got it:

https://www.rx7club.com/showthread.php?t=739896

"Elpena" (I believe) was the seller...

Jeff20B 04-30-08 01:14 PM

Those eagle flywheels tend to not have replaceable friction surfaces. Is yours down into the rivits? As long as the pressure plate diaphram fingers go horizontal as you install the pressure plate, it's ok. A new disc is helpful too. :)

Viking War Hammer 04-30-08 04:01 PM

yep, those fittings and hose sell for the price of gold..........

My fuel system is built with all -10 fittings/Hose, that was high dollar. Now I'm gathering all my cooling fittings/Hose, those are all -16 fittings. Those things are ridiculous expensive.

rxforspeed 06-02-08 05:49 PM

3 Attachment(s)
The tab keeps getting bigger...

I don't think I posted it here (I may have, but I don't have time to re-read my last few posts), but the damn fuel cell I had gotten was stolen. I should've figured-I got it dirt cheap. The asshole that sold it to me called me and begged me to bring it back to him before the guy he stole it from got the cops involved, so I figured if it was stolen I didn't want it anyway. Now I'm out the cash the asshole got me for, but at least I did the right thing...

Anyway, I figured I'd build my own fuel tank. Not a fuel cell, this will mount in the stock location and (according to Jeg's "mis"-calculations) should hold roughly 19.5 gallons of 93+ octane, pre-mixed with 2-stroke oil. I've just got the basic shape right now, but it'll be coming together soon. I've got WAY to many projects on my plate right now so it may be a couple of weeks or so before it's finished...

Here's some pics to get you started...

BTW-the "sump" cost me $5 from a fab shop I used to work at. I've got $60 in the material and time for the shearing and bending of the two plates, and the weld fittings (-08AN feed and -06AN return) were $8-$10 or so from Jeg's. I've still got some minor trimming to do before welding it up, and I'll make a small section to attach my stock filler neck and vent hose to after I drill a single 5/8" or 3/4" hole in the center of where the sump will sit. The return will feed directly over the sump's feed hole, so I should be covered even running less than a quarter of a tank. It's 16ga steel by the way, and the entire assembly should only weigh about 20-25lbs empty. Not too bad-considering it'll be over twice as strong as the factory unit and hold quite a bit more fuel...

Oh yea-here's the pics...

rxforspeed 06-02-08 05:51 PM


Originally Posted by Jeff20B (Post 8147672)
Those eagle flywheels tend to not have replaceable friction surfaces. Is yours down into the rivits? As long as the pressure plate diaphram fingers go horizontal as you install the pressure plate, it's ok. A new disc is helpful too. :)

I still don't have my clutch yet-it's on my "to buy" list right before the Tial 40mm wastegate. I've planned on running a new "street/strip" clutch-rated for 250ft-lb or so, just haven't gotten it yet. The rivet heads are still below the friction surface though, so I hope I'm OK. Thanks for the info!

Jeff20B 06-02-08 11:41 PM

Looking at that for sale thread again, it looks like I have the same flywyeel as you. I just installed it today but couldn't get the tranny back in. It just didn't want to go. I think the disc might be misaligned. I've never had this happen before so I'm open to suggestions.

Anyway there is no eagle symbol on the disc side but the other side looks spit'n image like yours. Could you take a picture of the disc side for me? Mine also only fits a 215mm pressure plate (it lacks the clearanced cutouts) which is perfect for my 215mm street strip pressure plate. I also have a 225mm HD disc that worked fine before with a light steel flywheel that also lacked the clearancing.

The fuel pumps arrived today. Thanks!

rotarymaniac 06-03-08 09:45 AM


Originally Posted by slate84 (Post 8099220)
ps. sorry, didn't see it was @40psi


Only 40psi??? I had a walborro 255 and it didn't pump enough for the TII that was swapped in my car. I'm now running 90 psi and that seems to get enough fuel to the motor.

rxforspeed 06-03-08 07:21 PM

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Originally Posted by Jeff20B (Post 8250613)
Looking at that for sale thread again, it looks like I have the same flywyeel as you. I just installed it today but couldn't get the tranny back in. It just didn't want to go. I think the disc might be misaligned. I've never had this happen before so I'm open to suggestions.

Anyway there is no eagle symbol on the disc side but the other side looks spit'n image like yours. Could you take a picture of the disc side for me? Mine also only fits a 215mm pressure plate (it lacks the clearanced cutouts) which is perfect for my 215mm street strip pressure plate. I also have a 225mm HD disc that worked fine before with a light steel flywheel that also lacked the clearancing.

The fuel pumps arrived today. Thanks!


Good to hear you got 'em. Check the paperwork for the new one to see what the output is. What I told you earlier was just an estimate, but that thing's built for carb'ed domestic V-8's and even quite a few older ones put out over 350HP from the factory. Should be adequate for your application...

About the flywheel-it's in my storage building right now but I can get some pics of it tomorrow. I may have a couple of images that I'd posted in another thread that I can post here for you. Let me see if I can dig 'em up...

Yea-here's a couple after I had the disc side resurfaced. BTW-does this rear counterweight look like it's for an SE 13b? The front counterweight came with the flywheel and rear c/w, but it's drilled differently then the stock manual tranny front c/w. I don't really trust just installing it-I've been thinking about using lighter rotors in the engine I'm building anyway, so I'll just have the entire rotating assembly re-balanced if and when I get the rotors...

Thanks guys...

Oh yea-90psi at the injectors? Damn, that seems pretty high-it doesn't affect their closing or operation? How long have you been running that pressure? Are the injectors high or low impedence? Have you had any problems with your fuel system since you've upped the pressure? I'm no EFI expert, but I'd think you could achieve the same result with a lower pressure and larger injectors. Are your injectors the stock units that came with your engine, and what size are they? I still haven't completely figured out my EFI system yet, or even what components I'll be using, so everything I've gotten so far is compatable with a carb'ed system as well. I think I'll keep the DCOE until I've got all my EFI parts and MSII built and ready to install. What fuel pump are you running?


One more thing-does anybody have any ideas or recommendations on how I should go about adapting AN lines and fittings to the barbed fittings on this damn MSD fuel pump? The 5/16" outlet isn't replacable, but I can change the 3/8" barbed inlet to an AN adapter fitting. I'd hate to use hose clamps and more barbed fittings to connect them, maybe I'll just get a different pump that's AN fitting friendly...

Jeff20B 06-03-08 10:54 PM

I think the claims in the fuel pump instruction sheet are a little optimistic as far as performance goes, But yeah I'm sure it will be plenty for one of my awesome projects like a 4 port 13B powered MG Midget or a 4 port 13B powered VW baja. Each one needs a fuel pump. The MG currently has a Facet that was inadequate at best (the sight glass always showed below center = low fuel pressure unregulated lol). The baja needs a fuel pump as I haven't built the fuel system for it yet.

On to the flywheel. Thanks for posting some pics! I see yours does indeed have the clearanced cutouts to allow a 225mm pressure plate. Man you got lucky. Glad it worked out in the end. My flywheel does not have these clearanced sections so I'm stuck using a 215mm pressure plate. The wear surface is large enough to allow me to use a 225mm disc though, so I'll end up with a grand total of 220mm of grip. A little better than 215mm, but not quite as good as a full 225mm. This should be more than adequate for the light FB rear end as long as I don't get super sticky tires. I don't want to run the risk of breaking axels and plenty of other things. I'll start with stock rims and tires and move up from there.

Your rear counterweight says 1029A. That means it fits any '85 or older 13B regardless of model. They can also say 29. I've used both. If your front counterweight says 1757, it matches the rear 1029A or 29. 1757 is the part number for '74-'75 13B engines with the 3B side plates and cool MAZDA rotor housings. If you look, certain parts still carry the 1757 part number such as thermostat gaskets because the part number reflects the first model with which they came out. Just like anything that came out with a certain model, for instance the '86 6 port RX-7 will say N326, or with the 20B it will say NF01. Mike j9fd3s showed me that trick. Try it yourswlf next time you order a set of corner springs. They'll say 'competition' or '3rd gen' when in realitry they have the NF01 part number which means they first appeared in the 20B; Mazda kept using them in the FD and they are compatible with 3mm apex seals. They work pretty well for me in my rebuilds. Check them out.

Phiber Optik 06-04-08 02:11 AM

Does anyone know what the factory GSL-SE 3/8" fuel line will support hp wise?

I'm a high reving V8 guy and I think I might be pushing on the door of a tank and main line upgrade.

REVHED 06-04-08 05:23 AM


Originally Posted by rotarymaniac (Post 8251319)
Only 40psi??? I had a walborro 255 and it didn't pump enough for the TII that was swapped in my car. I'm now running 90 psi and that seems to get enough fuel to the motor.

40psi base pressure is plenty as long the pump and injectors are big enough.

Jeff20B 06-04-08 11:40 AM


Originally Posted by Phiber Optik (Post 8254619)
Does anyone know what the factory GSL-SE 3/8" fuel line will support hp wise?

I'm a high reving V8 guy and I think I might be pushing on the door of a tank and main line upgrade.

Uh oh, you are incorrect. GSL-SE goes from 1/2" from tank to 5/16" to the line that sends fuel to the engine bay. At EFI pressures, it will probably support at least 300HP.

rxforspeed 06-04-08 05:35 PM

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I got more pics of the flywheel for you today, but it sounds like you might not need them. The thread where I found the flywheel clearly stated that is was for a 225mm disc and pressure plate, but the used clutch components were already sold by the time I'd found it. Thanks for the info, Jeff. I'll make sure to start noticing the factory part #'s for the stuff I order like that. I've actually got a lot of questions about the engine I'm building that I'm sure you'd be able to help me with, but I'll try to keep this thread more on the fuel system topic. If you get a chance, check out my build thread in the "regular" first gen section-I'll start posting questions there soon...

Anyway, just in case-I'll post the other pics I got of the flywheel today...

Phiber Optik 06-04-08 06:08 PM


Originally Posted by Jeff20B (Post 8255524)
Uh oh, you are incorrect. GSL-SE goes from 1/2" from tank to 5/16" to the line that sends fuel to the engine bay. At EFI pressures, it will probably support at least 300HP.



Humm I thought I remember the line comming out of the tank being 3/8" ID, oh well 1/2" should be plenty, it's all -8AN from there on up and it's a low pressure (carbed) system anyways.

I know the fuel line that runs from the stock pump location to the engine bay isn't big enough to support much power.

REVHED 06-04-08 09:16 PM

Rice Racing was running over 500hp with the standard fuel lines.

Jeff20B 06-05-08 04:50 PM

Thanks for posting pics of your flywheel. It is very similar to mine. It turns out the splines in my disc were bad so I had to dress each one with a file. The tranny mated up to the engine just fine after that. Haven't taken it for a test drive yet.

I saw that thread. Whenever you're ready to ask specific engine questions, I'm sure I can add my two cents.

I had a comparison list of fuel line sizes and HP for carb and EFI pressures. 1/2" at EFI pressure was good for 1000HP but only around 500HP for carb pressures.

rxforspeed 06-06-08 05:33 PM

Thanks man, due to massive storms and electrical outages over the past couple of days I haven't had a chance to get online. I've got a few questions that I should be posting here soon. Thanks for your help, man. BTW-any luck with the SE pump yet? I've seen some on Ebay for about the same price as that other pump-I'm not sure what the quality is like, but they're supposed to be new. I wonder if they're any good...

Jeff20B 06-07-08 10:59 PM

Ask away.

The SE pump smelled horrible from ancient gas so I cleaned it up as best I could and set it aside for a few days. I'll get back to it when the weather gets a little better around here.

I got my Walbro off eBay a few years ago so there is always that option for the guy I suppose. He happened to find a good deal on a useable pump here locally though, so he should be fine.

Hey I got to test drive the new flywheel. It has smoother engagement than the light steel. That's encouraging. Plus the engine now accelerates better while not hurting low speed useability in any way, as is sometimes the case with aluminum. Infact since it no longer shudders, it's actually easier to drive under parking lot speeds than it used to be. Win-win. I hope yours turns out as nice as this one did.

I do feel a slight vibration at idle, which could be caused by the pressure plate being off a fraction of a mm or maybe the flywheel isn't quite in balance anymore. The carb has a high idle problem (1100ish) so I'm going to throw another one on to see. Also my clutch hydralics don't like the SS pressure plate. :) Internal leaks most likly. The friction point keeps changing and sometimes is on the floor or beneath causing the tranny to get stuck in gear. Kinda funny.

rxforspeed 06-09-08 05:55 PM

Damn, Jeff-good luck with the carb and clutch problems. I'm glad to hear positive results about the aluminum flywheel though-it seems all the rotary performance parts retailers advise against running one on the street, but everything else I've read says that a light weight aluminum flywheel is best suited for light weight vehicles with moderate rear axle ratios (around 3.73 or lower-higher numerically). That description almost describes our FB's to a "T", so I figured I could live with mine even if it did pose a bit of low-speed driveability or engagement problems.

I'm going to order a new or remaned clutch master cylinder and slave cylinder, and I already have the braided stainless clutch flex line from RB. I hope that line fits better than their brake lines-I had a helluva time trying to get them to fit right. It seems like they wanted to cross-thread, and I even had to clean a few of the threads on the lines off with a file for them to properly engage. I eventually got 'em, but I hope I don't have to fight with the clutch line like that when I install it.

I'm planning on having my entire rotating assembly rebalanced with the flywheel on, so I hope I don't have any vibration issues once mine's installed. I still have a clutch to get, too. Would you recommend any particular brand? I've seen a few sets on ebay that are rated for up to 250+ lb-ft, and they claim to be a "street/strip" style (not a puck, but a sprung hub with a full 225mm disc) but I'm not sure if they're really the quality components that I want. I'd rather spend a few more dollars (or more) for a true high-quality clutch kit that will withstand the abuse I'll put it through.

BTW-if you haven't already, try bench-bleeding the clutch master cylinder. I spent about 15 minutes plunging the brake master cylinder from the SE after I rebuilt it, but it seems to work like new now. I still haven't fired up the engine for the power assist from the booster, but the pedal feel is excellent without it. It could just be an inner o-ring or seal in either the clutch master or slave cylinder causing your problems. Have you checked for fluid leakage around the two components, and inside the cabin where the rod from the pedal contacts the master cylinder? I've got a couple of both-after I get new or remanufactured units I can send you my old ones to use or for parts if you just need some inner seals...

Jeff20B 06-09-08 06:27 PM

On my setup, the SC adds some rotating weight so it makes the aluminum flywheel feel more like a light steel. That is why it's perfectly streetable. That is if you consider a light steel flywheel perfectly streetable as I do. :)

I gotta say though that switching from a stock '83-'85 flywheel to a light steel last year actually made the car easier to drive. Then switching to a really light aftermarket steel flywheel (only weighed 8 pounds!) improved things a bit more, although it required a tiny bit more awareness payed to the clutch but like anything in a car (steering, brakes etc) you get used to it.

If you already have experience driving a light steel flywheel, transitioning to aluminum is comfortable. It is actually less of a shock to the system than going from stock to light steel because once you experienced light steel, you kind of know what to expect.

I knew that the '83-'85 rotors were the lightest stock 12A rotors Mazda sent to this country, so I was a little concerned, but really loved how the light steel flywheel woke up the car (and made it easier to drive in the process, strange to tell). It still didn't zing (rev quick like a motorcycle engine) like I've heard from aluminum flywheels so I knew I still wanted more. Changing to the superlight flywheel (8 pounds which is basically the same as aluminum) was another step in the right direction. I wasn't driving it anymore at that point, but as a passenger, I was highly impressed by the performance out of a mild ported 12A. From what little I drove it, it was not hard to drive at all. It even had an HD disc producing a slightly more grabby engagement, but even as an unfamiler driver, it was not even close to a problem for me to drive it. Infact I got used to it the 2nd or 3rd time starting out from a stop. The learning curve isn't very steep with these things if you already know what to expect.

I'd say the hardest part in all of this is the very first time you gingerly let the clutch out on the very first test drive. After that, it's a piece of cake. I suspect you'll fall madly in love with the aluminum flywheel after the inital shock to your system wears off. Of course if you've ever driven a light steel flywheel, aluminum won't even be a shock. It will be rather expected. At least that's how it was for me.

By the way, my MG midget project has a 13B with the same port size as the 12A mentioned above and the same model of super light steel flywheel (stock disc though, for even easier engagement which is all that's needed in such a small light car). Its rearend is geared 3.7 and the tranny is one of those early ribcase 4 speeds with a slightly lower first gear than '79-'85 smoothcase trannies. I anticipate no problems with clutch useage in this car, other than the initial (first) test drive as I get myself used to it. I've driven this car before on a racing beat light steel flywheel (13 pounds) and it felt perfect to me back then, but I was fully used to driving a 30 pound stock flywheel in my REPU so if I could handle that kind of 'shock' to my system, I'm sure you can handle an aluminum flywheel in a 1st gen chassis. ;)

Jeff20B 06-09-08 06:45 PM

You should avoid clutches from eBay. People like dj55b thought they got a good deal on an XTD or whatever, and made sure to break them in properly and all that, but I bet I could make them slip if I drove their cars. I know my frriend Tom could. :)

hyper4mance2k didn't like the weak engagement of his eBay clutch. I decided to heed his warning and will only get quality clutch components like what you can buy from RB/MZTX like their HD disc and street strip pressure plates. It's a little more expensive, but they hold up for years under normal (I guess that would be spirited) driving.

Steve84TIIgs uses an HD disc on his 300HP T2 FB and it has held up for probably 7 years now. Light steel flywheel and I think a street strip pressure plate too. All in the T2 240mm size. His tires are grippier than stock and his clutch holds up fine.

I plan to use stock tires for now so my current setup with the Camden should hold up fine. I even chirped the tires a few minutes after the first fire up just to christen the driveway. :) I know, I know it's not good to do that to a non broken in clutch, but it's never been a problem with quality clutch components before. Infact my friend with the supercharged rotary 510 was out doing donuts with less than 10 miles on a brand new Exedy disc and old scuffed aluminum flywheel with 215mm street strip pressure plate (both from the early 90s, well worn but a scuff job is all they needed with a scotchbright disc pad thing). I don't think an ebay clutch could do that and live very long after. :) His has held up through several donuts, especially after the posi diff went in, making them even more fun and numerous. :)

Jeff20B 06-09-08 06:58 PM

When I rebuilt PercentSevenC's clutch master and slave, the braided slave hose seemed to go right in. Threaded were fine. Perhaps the brake hoses are of less quality control.

I'm going to get a braided stainless hose for mine. Even if it might not make a perceptible difference in clutch engagement or feel, it is a little cheaper than stock rubber and looks kinda nice. Might as well.

I already did bleed the clutch stuff, and it held up while test drving it with the light steel flywyeel right before the swap, but since the swap, the engagement point is all over the place. It could be a simple bubble, which bleeding would remove, but this clutch setup has had problems since last year witht eh 12A and stock pressure plate. It did it close to home then never did it again. Then it started doing it a lot more frequently with the 13B. Now it's constant so it's gotta be aged seals probably leaking or bypassing internally.

The master looks like it used to leak but only recently developed a wet spot there. Nothing major though, so it's gotta be an internal problem. I'll look into both cylinders to see whether the rubber is bypassing, or the actual metal is slightly pitted, as was the case with Percent's.

If they're deemed rebuildable I'll just throw some new seals in both cylinders like I did in Percent's car and it should be fine. His engagement is very reliable even though the bores of both cylinder did show some wear/pitting. New cylinders would be better, but seal kits are cheaper and it gives you chance to see how much life is left. I'd say "rebuild them once, then replace" is a pretty good rule to follow.

If you'd like to send me your old cylinders, there is a chance they'd be in better shape than mine. Give me a chance to remove mine and gut them first though. I'll get around to it as soon as the weather is nicer.

rxforspeed 06-25-08 10:42 AM

Sorry it's been awhile since I've checked this. Yea, let me find a good quality new, rebuilt, or remanufactured clutch master cylinder and slave cylinder and I'll send you the ones from the SE and the ones out of the GS (the one's I'll be replacing).

Thanks for the info-I'm sure you've just saved me a major headache a quite a few bucks down the road by advising against the ebay clutch stuff. It might seem like a good deal, but you really get what you pay for in the end. I'd rather spend a lot more money on true quality components that'll last twice as long or longer and really save money by not having to replace them sooner. I'll get some stuff ordered and installed and send those parts out to you soon...

Thanks again man!

StealthGXL 06-25-08 08:52 PM

What's the deal on the fuel system . . .


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