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Oh poo poo, Gen 1 RX-7 content and questions and I missed it until now! In the US I know where I'd go to get stuff, but you're not in the US so recommending stuff from over here would be pretty silly; I'll do some poking around when I get home from work. The rear end has more issues than just the sway bar too; the sway bar was actually a bandaid fix. But the proper fix isn't really quite a bolt on thing.
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Mar 7, 2016 22:50
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Well, Techno Toy Tuning has some nice looking stuff here: https://technotoytuning.com/mazda/fb or if you have welding ability, something like https://technotoytuning.com/toyota/ae86/weld-lower-control-arm-kit-ae86-corolla and the stock control arms would be cheaper. Or really you could DIY the same idea. Actually what I'd be really tempted to do is go the "cut the control arm and fit a rod end" route, then press in a different ball joint. I couldn't quote you exactly what one but from what I recall a Mazdaspeed 3 ball joint can be pressed into the RX-7 control arm, which gets you a straight pin instead of a tapered bit with a threaded whatsit. And that straight pin happens to be the same size as the pin the S4/S5 RX-7 knuckles bolt to, which gets away from the stupid strut solution. Might take a bit of fiddling with struts to get something the right length and all (I'm not sure 2nd gen stuff is exactly right) but there's a lot of advantages, you know? Rear suspension... stock was unequal length 4-link and watts link. The circuit race solution over here is moving to 3-link plus panhard - 3rd link going to the top of the diff forwards to the trans tunnel. Where class rules require no hacking up sheetmetal, the link is actually bent and anchors at the roof of the trans tunnel about even with the lower link. Panhard mounts about even vertically with the shock mounts. No solution here that doesn't require fab though, I don't think. Try looking up Charlie Clark at KC Raceware (googleable) Then again, without much lateral force, binding issues in the rear suspension might not be as important. Probably circuit racers over there have other ideas, but I won't pretend to know who's reputable.
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Mar 8, 2016 01:41
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Really, it's just like tuning a good piston engine. 2 strokes get into the whole bit of trying to prevent sucking fuel out the exhaust port by timing things with the expansion chamber, and that's not a relevant concept for rotaries - there's not a hell of a lot of overlap flow. Collector length, there's a lot of different ways to skin the cat. After the axle is one, sure, but another one is, ah, 55-60cm or so for a street port. Tuning for a different standing wave, but it works and it easier to package. In some ways. Two narrower tubes instead of one big one are easier to fit under the car. And in my experience, street porting is usually a bunch more than a "few degrees" more duration, but I'm of the view that there's no point pissing about if you have the thing open anyway, you know? A Weber and suitable manifold wakes the things right up. There's some adjustments on the worm and ball steering that let you take some of the play out. Rack and pinion is still better, of course, but is kind of a pain in the rear end to actually do.
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May 14, 2016 16:13
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Kaptainballistik posted:The issue is Steering shaft flex more than the Steering box.... But we have the technology...... For someone on the other side of the planet, who or what are CHU?
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May 16, 2016 12:14
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Huh, be interested in hearing more details of that. Why Galant VR4 struts in particular, what do you mean about the sway bar (I've seen all sorts of setups), what 6-speed, questions like that. Oh yeah, and one of the Weber based EFI setups, or one of the 4-throttle setups that are available over there? I'm getting the urge to haul one of my S3 cars from my folk's field to my barn and start doing some surgery for road use or something. I know how to fix the rear suspension to my liking, and have ideas on the front suspension too - something to the effect of S4 knuckles/struts with homebrew control arms and a rack and pinion. Was thinking of rotary swapped Miata, but I *have* a bunch of S3s and precisely zero Miatas to rotary swap...
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May 16, 2016 15:23
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No worries; different attitudes and stuff. Over here, all the competitive roadrace classes that rotary stuff is eligible for have rules regarding induction systems (Weber with 42mm chokes on a streetport, for example) so there's not much to be seen and nobody much cares about covering anything up, and suspension stuff for the live axle Mazdas all converged towards one basic design with whatever shocks people are willing to pay for (and sometimes that's a lot; did you know Dynamic Suspension are more than happy to build you stuff for whatever you want if you throw money at them?). Some of the top running cars have IPRA money into them, but to a different rules set. So I get real curious what happens over there because the rulesmakers took a different path, you know? There's a lot of knowledge about making streetported 6-port 13Bs with Webers make good power, but almost none about making bridgeports (or anything but peripheral ports really) with unlimited induction go. And it's not like someone is going to bother doing proper development for a street car.
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May 17, 2016 13:44
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Interesting homebrewed throttle setup - some sort of production throttle bodies with an adapter? Curious what all is going on in that plenum, looks like a bunch of stuff in addition to the injectors firing down the throttle bores. Also, holy poo poo on the Subaru brakes - I always figured the "Group N" spec was back to when the cars were lighter, or was some sort of cruel joke or something. Is there *anything* you're allowed to do with ducting - maybe with some of those fuckoff-powerful electric brake fans and water spray? I know I've seen stuff over here to get air moving at the right place (thought Rooducts were a cool idea) but yikes. Rally may be a bit of a joke over here in the states, but at least the sillier parts of GrN never came to much.
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Jun 6, 2016 13:43
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CAT INTERCEPTOR posted:Now thinking of classes and racing. I have something worked out why the USA just does suspensions and a few other things so loving badly and being focused on loving poo poo that doesnt matter - what matters is what the gently caress happens beyond the limits of grip, build it fast there, it'll murder grip queens. The reason whyt he Aussies focus on a world of mods the USA doesnt do is the classes are capacity limited, not mods limited. So you get utterly stupid statements like anti roll bars controlling geometry and fixing so called geometry issues - Dont care who you are, you say this, you are a loving moron - while this gets you laughed off the track Down Under. But you lock the poo poo out of the suspensions with ginormous bars in the USA because that's all you get without getting into virtual sports sedans. Here.... well I'm against 2 to 3 litre cars with freedoms immediatly like brakes and suspensions other than mounting points. So if I want I can reset the Watts linkage s long as it attaches to the body in the same location or lengthen the to control arm. Deleting the sway bar is the "You have to stick to rules" solution to the diff binding issues - Type II and III rulesets give me a *lot* of options, even with obeying the original mount points rule. So I can also go to full adjustible front control arms and coil overs immediatly. That's pretty much right. In the 70s and 80s or so, "Production" classes had freedom to move suspension pickup points around, but in the 80s and 90s when professional racing over here was based off small bore tube chassis cars and you could pick up used ones for cheap, a lot of the Production cars got folded into the same classes as the tube chassis "GT" cars, which as I understand it end up about the same as your Sports Sedans even if the rules are laid out a bit different. Around this time "Improved Touring" came about which let you screw with nothing other than springs, shocks, sways, air filters and exhaust, and enough people built it that they adopted some of the ideas to save Production, which by this point had everything newer than like, Triumph TR6s and Austin Healy 3000s and the like migrate out - idea sorta was that an RX-7 or Datsun 240Z with limited suspension and other limits would turn about the same lap times as an old school British roadster with open suspension. It pretty much worked, but here we are. Then the pro classes over here went to a different rules set, so the supply of tube chassis cars died out and to save the smaller GT classes (GT-1 is always healthy because it's not a hard sell to get rich people to shell out for the fastest closed wheel class on track) they put some of the newer pro class style cars in with the GT classes, and made another class called "Super Touring" for the others, which end up sorta like Improved Touring but with freeish brakes and engine swaps allowed to a point. That's ignoring the spec classes and a bunch of other poo poo. (this is all SCCA stuff which is the biggest non-pro racing rulesmaker over here; there's other groups you can race with but they're a lot smaller) So, for an example, you build an RX-7 for roadrace over here. In increasing order of spending you can build to Improved Touring (where you strip the interior except for the dash, cage it, put on a header and stuff, any DOT-R tire that fits on a 7 inch wide wheel, any brake pads, any sway bars, strut inserts, shocks and springs that retain the original knuckle, any ring and pinion and LSD you want, and bolt on suspension links), Super Touring (IT, plus you can do more to the engine or swap to another Mazda engine, replacement suspension arms, and throw 4-pot brakes on it up to a given size) Production (IT plus you run oddball slicks that fit on 7 in wide wheels, wide bodywork, extend ported engine with a Weber, non-sequential racing transmission, and a lot more extensive roll cage) or GT (variety of engine possibilities depending on which GT but up to peripheral port, tube chassis, wide slicks, free brakes, etc). Most of those classes you're not allowed to modify anything other than what the book says you can. If this all seems like rules written by committee, well, it is. Oh, and until the Super Touring classes came out, if you wanted to roadrace anything with a turbo you're pretty much SOL. SCCA's point is that it's hard for a group of volunteers with massive variety of cars coming through tech to make sure people aren't cheating with turbos; I can't really say they're wrong. As a kind of funny aside, some engineer in the late 90s figured out how to make a 3-link rear suspension plus replacement panhard work in the 1st gen RX-7 within the letter of the Improved Touring rules. IT had allowed "bolt in suspension device" which was meant to be slapper bars or the like for live axle cars... but what this guy did was come up with a mount point that bolted to the inside of the trans tunnel without bodywork surgery, and special replacement bushings for the upper links that just happened to be made out of seat cushion foam (you have to keep the stock links, but bushing material was free). So fixing geometry over here isn't necessarily completely hopeless, just a lot more of a pain in the rear end than it could be.
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Jun 13, 2016 14:14
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The tri-link as they did it to get around rules is a nasty kludge to be sure, but if you look at live axle tube chassis cars and do some math, they do have advantages. Of course, equal/parallel 4-links work too, and if you have the oldschool IMSA factory prep manual for the RX-7 that's what they did there, at least for a while. Watts links definitely do work, but Mazda was stuck trying to package things and so here we are. Best? Depends, doesn't it. In practical installations, Panhards tend to have less unsprung weight and be easier to package, Mumford links have their advantages (and impress engineers) and I've seen a lot of small bore cars with a 4-link that has the two lower links triangulated to one spot on the diff, which is probably the lightest of all of the solutions. Actually, one Watts setup I thought was kinda neat that I saw last weekend had the center link on the chassis end instead of the diff end, with the pivot point on a slider and adjustable with a big screw, though it'd be hard to do on a production based chassis. I know, sorry, this is what happens when you have an engineer thinking about this crap for 15 years.  The bit that makes me pull my hair out about the front end is that there's no good way to fit a rear-steer rack around the engine, and a front steer rack interferes with the tension rods. That and the strut tubes being integral with the knuckles making it a gigantic pain to do a decent strut.
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Jun 15, 2016 14:27
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AWD LS1 wagon? Holy poo poo, I would rock that. Well, especially if there were a way to get it as stick too? (I'd be amazed though) Seriously, why do you guys get cooler GM products than the US does? It seems so counterintuitive.
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Jul 9, 2016 14:22
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Dammit, I'm getting urges to work on my GD stuff now. Just need to machine the new transmission and then put the front LSD in... and get a new clutch... and fix other stuff while I'm in there... 
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Aug 7, 2016 16:05
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Ugh, all of this... now I'm checking local classifieds for Subarus old enough I don't have to pass emissions, and also for EG33s. Dammit.
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Aug 8, 2016 18:19
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Every time this thread comes up I start looking at internals for my EJ20 build, which I really don't need parts for as it's a few projects down the line. I suspect you've done enough Subaru stuff by this point that it looks easier than I've found it.
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Aug 13, 2016 14:53
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Rotaries are stupid easy until you're starting to try to figure out where the last 10-5% of power available out of an extend port (well, we call them street ports over here - not bridgeport anyway) 13B is. But that's fun I guess. I guess I'm just mildly pissed off because I'm trying to figure out pistons for a built EJ20 that will hold the power I want but won't need a rebuild in a couple years and that's a dataset that's pretty drat lacking.
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Aug 14, 2016 02:42
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That breaker bar reminds me of my Rotary Flywheel Removal Stick, which is a piece of like, 4-5mm web angle iron with holes drilled in it welded to a 2m long piece of square tube. I love custom tools.
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Aug 14, 2016 19:42
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This is like how I was for a while with S2/S3 RX-7s...
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Sep 16, 2016 13:34
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I have to say after doing the clutch on my WRX, I question the decision of anyone ever to race a Subaru. (this may be biased by everything being rusty. Or I've been spoiled by working on race RX-7s)
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Dec 6, 2016 16:03
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I guess. drat trans just did not want to go back in place. Then again, there's all that emissions crap in the way too... (I won't touch anything with a transverse engine)
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Dec 6, 2016 20:12
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Your continued acquisition of cheap Subarus keeps making me think I should get a testbed unibody to try stuff before I do it on the WRX. But then I remember how many other projects I have on my plate. And I get tempted to do stupid things like order a pair of EJ207 heads off ebay.
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Dec 29, 2016 14:28
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Over here, I'd be tempted to megasquirt the sucker, but I have an irrational hatred for OEM ECUs, or at the very least OEM wiring harnesses. ... I mean that's probably not a *good* idea, but it would be fun to watch.
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Jan 5, 2017 13:31
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CAT INTERCEPTOR posted:Not this one, it's an innocent victim of a Jeep. There's a drat YOU KASTEIN!!! joke there somewhere. I have about a dozen 1st gen RX-7s, but am not really trying to get any more, does that still count?
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Feb 6, 2017 12:38
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CharlesM posted:I still really want a GSL-SE. For whatever reason I'm seeing a relative lot of them going for sale lately. If I didn't already have one though, I'd just put an S4 or S5 13B into a GSL, do one of many solutions to convert the front to FC hubs and redrill the rear axles. There's nothing that special about how Mazda built them as opposed to the normal GSLs.
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Feb 6, 2017 14:57
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Kaptainballistik posted:SUUUUUUURE......you just tell yourself that. Well, unless I start running them in the US's rather modified circuit class (E Production) it's not like I'm depleting my supply of shells, and I have to get my racing strut development project online before that since there's no reasonable options that are credible - I mean I bet MCA over there would do a setup, but that's a bit of a pain to have rebuilt (shipping it there and back I mean) But then again EProd is one of the most competitive classes over here and 1st gen RX-7s are surprisingly relevant. Part of me does imagine building up a cache of identically prepped, stripped, seam welded and caged shells, and design everything too expensive to have spares of to swap between them. Goddamn, I just realized how that sounded.
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Feb 6, 2017 22:43
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Kaptainballistik posted:Gooood GOOOD American circuit classes end up with weird rules quirks - EProd allows widebodies, moved suspension (as long as you don't cut the unibody) and extend port 12As or 13Bs with your choice of stock, alternate synchro or dogbox all with a variety of weight breaks (there's a total of 6 possible weights to run a 1st gen at) but restricts you to 13x7 or 15x7 wheels. Of course, the rules have been stable on the wheel width for decades, so Hoosier has a tire intended for the class, which puts a 9.5" wide slick comfortably on a 7" wheel. Oh yeah, and stock calipers and rotor sizes are required for some reason - at least now, after a few people had their wheels part company with the car, they allow RX-7s to run an aftermarket hub where the bearing carrier's not part of the same casting as the rotor. (sorry, ranty mood)
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Feb 7, 2017 15:06
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Don Dongington posted:AI needs 100% more Escorts. I actually was kinda looking into what it would cost to get one into the US. (more than I have)
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Feb 9, 2017 15:20
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Given access to metalworking tools and the Ford Escort prep manual though, an Escort seems like a fun canvas.
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Feb 9, 2017 23:56
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Hm, thinking... if you don't care about running anything other than engine stuff, how little wiring harness is needed? I'm thinking of building an engine-dyno-only GD ECU setup in the next year or so... or once I have the engine dyno going.
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Feb 26, 2017 16:35
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CAT INTERCEPTOR posted:Basically whatever connects to the two blocks under the fuse box and whatever else you want to have active like fuel pump etc. Also you can cut a huge amount of length out of a lot of wiring, given that for some odd reason the fuse box section of the harness goes from the drivers side footwell, around the nose and up under the passenger side from guard. Does it come with free spiders?
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Feb 27, 2017 15:23
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CAT INTERCEPTOR posted:What kind of spider do you want? Redback, Funnel Web or Long Leg? Will any of them survive -20C weather? I mean, what's the point of having a terrible invasive species if it'll just die? (seriously, I'll just junkyard a harness when I get to that point - too much sorting of the dyno itself first)
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Feb 27, 2017 20:25
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CAT INTERCEPTOR posted:Funnel Web's are pretty good at finding holes to stay warm in You know, put like that sure, as long as shipping isn't too ruinous. Is this GD-equivalent?
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Feb 27, 2017 21:59
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How big are you guys up to? Here they recently changed it so that you can run 34mm with unrestricted boost, or 36mm with a limit of 2.5 bar absolute.
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Mar 24, 2017 14:14
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CAT INTERCEPTOR posted:We do it smarter. Run as much boost as you want but you get PUMP 98ROM for a 36 or E85 / race grade 98RON for 34. Wanna run 40psi? Sure. It'll go bang but knock yourself out. Pointless nerd sperging here, but I don't know that that's "smarter" per se, though certainly easier to tech. The problem in my mind is that having fuel octane related limits on boost opens the door for all sorts of WRC style anti-detonation solutions adding a competitive advantage, whereas the engine I saw built to the US style 2.5 bar boost limit was nice and simple, albeit using MS109E for fuel, and made 320 horsepower and 400 ft/lbs at the wheels, not flywheel. I mean, it'd be silly to build a full house WRC spec engine for ... almost anything funded by one's own pocket... but shoveling money does get you a competitive advantage one way vs. the other. Speaking of silly, it annoys me how it's essentially impossible to get a GC Impreza without rust holes in my area for less than about $5k.
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Mar 28, 2017 13:56
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CAT INTERCEPTOR posted:There's just no gettting around what you can do on pump fuel - no amount of trickery is going to stop the A/F going into piston meltdown zone. And there's also no denying that pump fuel just does not have the consistency of race fuel (even 98RON race fuel) so you HAVE to have a safety margin. When they say pump fuel they literally mean comes out of the hose at a regular service station. You cant work your way around that. One of the tricks they pulled on the WRC motors was bronze rings at the top of the cylinder to pull heat away from the combustion chamber faster; yeah you won't be able to get to WRC boost/compression levels due to that they were running better fuel, but it'll help. Ion sensing ignition with an ECU that can look at it can look at cylinder pressure traces each ignition event and keep things right at tickling detonation levels (you can *see* detonation onset before it's dangerous that way) and you can use oil squirters to do a lot of interesting tricks with keeping piston crown temperatures down... and that's just off the top of my head. I mean you could argue it's pointless spending for stuff less than world championship level and I'd agree, but I know of a bloke who had about a $10M development program to win the national championship race in a clubby circuit race class here in the states, for the glory of a plastic trophy and his name in the record book... and it was just one of the three classes he was running in.
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Mar 29, 2017 02:17
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Yeah, weird thing is that the "Open" class here is sort of WRC+, in that if you read the rules it lets you do things like cut off everything past the firewall and rear bulkhead and make new clips. I think it would actually be hilarious to build a car to the class if I had the cash and the championship weren't so much about trailering, because of little things like the fact that non-turbo engines don't actually have to have any sort of air restrictors. Fundamentally you could make something akin to a Metro 6R4, or worse, something with that layout powered by a 6L pushrod V8 with no restrictions at the same minimum weight as the turbo AWD things. The Limited Open class they started a year or two back here sounds more like what you're talking about, with things being much closer to GrA. You guys ever played with piston sprays and such? Sorry, I'll stop fishing. 
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Mar 30, 2017 14:37
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CAT INTERCEPTOR posted:But seriously...... havent I got enough loving Subarus? That's like asking if I have enough rotary poo poo yet.
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Apr 26, 2017 13:57
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Part of me does keep thinking of putting an FT86 top (side?) end and manifold on a built WRX short block though. Extra injectors in the intake manifold should help with carbon, and then you'll have ports that work and poo poo.
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Apr 28, 2017 01:13
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Well yeah, I meant in a parts mixing and matching sense - I don't think the full FT86 engine will bolt to the Subaru transaxles. And DI itself is fine for high revs - evidence the Ferrari 458, and a lot of other racing crap including F1 nowadays - but there seem to be flow limitations in the available injectors, yeah.
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Apr 28, 2017 01:59
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Probably just the same sort of situation as EFI in the 80s, where even stuff as well funded as Honda's turbo V6 needed to run two injectors per cylinder just because they couldn't get bigger ones. Sooner or later, availability of bigger DI jobbies will come along. Or, well, just throw port injection at it, whatever. CAT INTERCEPTOR posted:Otherwise the FA20 just has the usual bolting arrangement that Subaru have had for years. Enh, I'd never been able to confirm that for sure without laying down money. But OK, even easier. mekilljoydammit fucked around with this message at 02:14 on Apr 28, 2017 |
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Apr 28, 2017 02:09
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That does it, boxers suck, screw the idea of a 207 into my WRX, I'm chucking the peripheral port 13B in! OK, I joke about that, but I was thinking about that for my rustbucket GC at one point.
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Apr 28, 2017 02:22
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I do know the oldschool solution was to take the compressor cover of those TD05s and put them on the lathe to turn them into a straight inlet for the later style motors. I'd be more than a bit tempted by that in your shoes... but then, I have a lathe.
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May 14, 2017 14:44
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