wvumtnbkr Posted April 27, 2017 Report Share Posted April 27, 2017 (edited) Im Starting this thread for a friend. We have an 1983 or 1984 (depending on who you believe) RX7. This car has won many races in Lemons and finished in the top 3 at every Chumpcar race it attended (3 or 4 of them). Since it's 2nd place finish in 2013 at High Plains raceway, it has sat in my garage. Now, it is going to be resurrected and made even fasterer! Here are the steps to getting it ready for this year. (In no particular order) 1) New Gauges (already purchased and arrived) 2) New radiator (Linky here...http://www.ebay.com/itm/DUAL-CORE-Aluminum-Racing-Radiator-for-89-92-Mazda-RX7-FC3S-late-2-ROW-2-/191724997831?hash=item2ca3b34cc7:g:0McAAOSwYHxWL32N&vxp=mtr ) 3) Swap in 13B from our other race winning RX7 complete with harness / ecu, everything. 4) Use stock trans from 12A and bolt to 13B. 5) Create / Install airdam 6) Create / install lexan "hatch" 7) Create / install fuel surge tank 8) New window net 9) Install chump stickers 10) 11's in driveway 11) Fix rear quarter panel. 12) New brake pads 13) New tie rods / ball joints 14) Fill fluids 15) Race I gots to go check swap values..... Edited April 27, 2017 by wvumtnbkr 1 Quote Link to comment Share on other sites More sharing options...
mhr650 Posted April 27, 2017 Report Share Posted April 27, 2017 That radiator is for a second gen, I tried to fit a stock second gen radiator in my car and there was no way that it would fit without a huge amount of work. The second gen radiator is installed at a steep angle while the first gen is installed straight upright. This is the radiator that you want, they sell 2 different size radiators on eBay. If they are listed correctly, which they are often not, the choices are a short and thicker version for the 79-82, and a taller thinner version for the 83-85. You want the larger surface area of the 83-85 radiator, I have this radiator and it works great, it took a little trimming here and there for things like clearing my larger front sway bar and to allow the hoses to pass through for my second gen oil coolers. http://www.ebay.com/itm/83-85-MAZDA-RX-7-RX7-FB-S3-3-ROW-CORE-FULL-ALUMINUM-RACING-PERFORMANCE-RADIATOR-/161599780829?fits=Year%3A1984|Model%3ARX-7&hash=item25a018f7dd:g:I2MAAOSwU8hY8DVq&vxp=mtr Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted April 27, 2017 Author Report Share Posted April 27, 2017 Cool! Thanks for the heads up on that! Quote Link to comment Share on other sites More sharing options...
bbaker480 Posted April 27, 2017 Report Share Posted April 27, 2017 Thanks Rob! I finally got logged in here and was thinking I should start a (re)build thread. The radiator information helps a ton, I think the hood has been closed for as long as the car has been sitting in the garage and nobody has really compared it to the FC. I'm excited to get moving on this once we get the 2nd gen ready for WGI. Quote Link to comment Share on other sites More sharing options...
mhr650 Posted April 28, 2017 Report Share Posted April 28, 2017 6 hours ago, wvumtnbkr said: Im Starting this thread for a friend. We have an 1983 or 1984 (depending on who you believe) RX7. This car has won many races in Lemons and finished in the top 3 at every Chumpcar race it attended (3 or 4 of them). I gots to go check swap values..... It's a mixed bag, the good news is that 2318/146 only gets you 15.9 pwr so you only have to pay the 50 point minimum. The bad news is that you have to start with the GSL-SE value of 200 points, so swapped first gens start at 250. I know some guys who are really screwed, they swapped in a Renesis from an RX8, those are ridiculously over rated at 238hp which gives them a starting value of 915... You are probably set for S4 parts since you have everything from the other car, but I have some useful S4 parts for spares if you need anything. I have an air flow meter and air box, coils, injectors, ECU and a few other things that I don't have a use for. Quote Link to comment Share on other sites More sharing options...
Ron_e Posted April 28, 2017 Report Share Posted April 28, 2017 A number of second gen RX-7's have made it to impound and even podium. Has a first gen ever made it to impound? I only know of one first gen with a class win. Wait a minute, Malice in Blunderland first gen I think had a few wins but that was with a Ford 302. Quote Link to comment Share on other sites More sharing options...
mhr650 Posted April 28, 2017 Report Share Posted April 28, 2017 (edited) We have made impound, won B class, and set FTD at chump races, the Rotary Rotards have won B class a few times. Against similar cars we won GP2 both days, overall on Sunday and FTD. my problem now is getting drivers, everyone has other commitments. I really would like to qualify for the Eastern chumpionship at AMP this year. Only a few cars have run in the 1:35's but I have 6 different drivers that have run 1:35's Edited April 28, 2017 by mhr650 2 Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted April 28, 2017 Author Report Share Posted April 28, 2017 9 hours ago, Ron_e said: A number of second gen RX-7's have made it to impound and even podium. Has a first gen ever made it to impound? I only know of one first gen with a class win. Wait a minute, Malice in Blunderland first gen I think had a few wins but that was with a Ford 302. We have a couple of chump trophies with this 1st gen. Quote Link to comment Share on other sites More sharing options...
mhr650 Posted April 28, 2017 Report Share Posted April 28, 2017 (edited) A first gen with a 13B is capable of competing for overall wins, I believe that I have taken my car as far as anyone in ChumpCar and I know that it is fast enough to win. I also have a stable of really fast drivers, unfortunately they are off doing different things so we don't get to race as much as I would like. Plus I am likely to be moving to the UK pretty soon so that is good news for the other front running teams in the Southeast lol. If you really want to go fast in a first gen RX7 here are the 3 major must haves. 1. Ditch the 4 link rear suspension and watts link. 10 points for 3rd link and 10 points for panhard bar, goodbye snap oversteer. 2. Ditch the stock first gen brakes, they are a nightmare of too much rear bias and prone to spins when the rears lock up. Second gen brakes fit easily in the 2X, and you can brake with anybody else on the track with those. 3. Ditch the stock EFI system, it is ancient and archaic, install a good aftermarket ECU and run the car in speed density mode and you can have decent AFR’s throughout the rev range instead of going pig rich at high RPM. I paid the 75 points when I converted mine, it was that valuable to me, now at 0 points it is a no brainer just a lot of money and work. If you don't believe me about the brakes watch the black car at the end of this video, this car has an RX8 Renesis engine so it is reasonably fast on the straight but it still had first gen brakes. Edited April 28, 2017 by mhr650 Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted April 30, 2017 Author Report Share Posted April 30, 2017 12a is out. 13b is sitting on the floor ready to go in... Shizz just got real yo. Quote Link to comment Share on other sites More sharing options...
bbaker480 Posted April 30, 2017 Report Share Posted April 30, 2017 4 hours ago, wvumtnbkr said: 12a is out. 13b is sitting on the floor ready to go in... Shizz just got real yo. 12a out and Rob's 3400 out, all after moving my furniture to my new house. Not bad for a day's work. Quote Link to comment Share on other sites More sharing options...
Darin Posted May 1, 2017 Report Share Posted May 1, 2017 All pictures, info, write-ups, etc are appreciated, as our team is pursuing the same idea. Keep up the good work, and tell us everything you go through! Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted May 1, 2017 Author Report Share Posted May 1, 2017 The swap is cake. I will tell you all of the little details right meow.... 1) Drill or slot your motor mount holes in the subframe 20 mm towards the front of the car. 2) Use the stock 12A type transmission 3) Use a GSLSE oilpan - needed to clear the steering linkage and fit the 20mm longer 13B engine 4) Use a 12A front cover - You will need to premix (you should anyway) - READ THIS!!!!!!!..... https://www.mazdatrix.com/faq/pulley.htm ... Don't ruin your engine. Read that! 5) Use the stock S4 NA harness / computer / sensors - you will need to run some wiring that is normally part of the S4 "car side" of the harness. I will elaborate on this more when we actually get to that point. 6) you will need a new header or modify yours or do something to figure out the exhaust. Pretty simple. It is as easy as the Honda swaps.... Same driveshaft. Same trans. Same shifter. Same mounts. Just need to change out the oil pan and front cover and drill 2 holes.... Quote Link to comment Share on other sites More sharing options...
bbaker480 Posted May 1, 2017 Report Share Posted May 1, 2017 I'll do my best to document and share. We didn't actually expect to get started this weekend but our plans got changed a bit and things just happened. I'm in the process of moving right now as well so there might be a few days between updates. I plan to get the engine bay stripped this week, order an oil pan to clear the subframe and steering linkages. While I'm under the front end I also picked up all new tie rods and ball joints just to be safe. I think I'm going to patch all holes in the firewall and start off fresh, drill and grommet where needed for the 13B and chassis, and paint the engine bay white. I know Rob is excited to get this out of his garage after 4 years of storage so once it runs I'll be hauling it home to build the dash, do all the wiring, etc... Lots of exciting updates to come! Quote Link to comment Share on other sites More sharing options...
mhr650 Posted May 1, 2017 Report Share Posted May 1, 2017 Make sure to get the Moog idler arm, no more melted idler arm bushings. 1 Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted May 1, 2017 Author Report Share Posted May 1, 2017 I've got some bad news Bryan..... I don't want to take the front cover off of the 12A that came out. It is worth more money as 1 unmolested piece.... So, the shopping list right now... oil pan from GSLSE 12A front cover Large oil filter and housing Walbro external fuel pump Radiator - aluminum Flea bay crap Radiator hoses That's all we should need to get it started and running! Quote Link to comment Share on other sites More sharing options...
bbaker480 Posted May 1, 2017 Report Share Posted May 1, 2017 27 minutes ago, wvumtnbkr said: I've got some bad news Bryan..... I don't want to take the front cover off of the 12A that came out. It is worth more money as 1 unmolested piece.... So, the shopping list right now... oil pan from GSLSE 12A front cover Large oil filter and housing Walbro external fuel pump Radiator - aluminum Flea bay crap Radiator hoses That's all we should need to get it started and running! I've got no problem not tearing apart a perfectly good engine for a single part. Atkins Rotary lists a 12A front cover (used but repainted) for $85. https://www.atkinsrotary.com/store/79-85-12A-Rx7-Reconditioned-Front-Cover-1480-10-600C.html. I can pick up the oil pan there as well, same price range as Ebay. I assume I need the baffle and gasket for the GSLSE oil pan as well? 28 minutes ago, mhr650 said: Make sure to get the Moog idler arm, no more melted idler arm bushings. I ordered new bushings for the idler arm, is the Moog part itself different? I think they were pretty cheap as well but I didn't see how the arm itself could be bad. Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted May 1, 2017 Author Report Share Posted May 1, 2017 No baffle or gasket needed. Pickup is needed.... Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted May 1, 2017 Author Report Share Posted May 1, 2017 http://www.ebay.com/itm/Diesel-Fuel-Filter-Mounting-Head-3-8-NPT-1-14-Center-Threaded-Spin-On-Mount-/292028167879?hash=item43fe3c36c7:g:mF8AAOSwtfhYn22i&vxp=mtr Buy a spin on filter and I gots the rest of the hardware for the surge tank. Lemme see what pump I bought.... http://www.ebay.com/itm/300LPH-Universal-External-Inline-Fuel-Pump-Replaces-BOSCH-0580254044-044-/331277337290 This one should work. Order those parts! I wanna get this thing together! and out of my garage... Quote Link to comment Share on other sites More sharing options...
mhr650 Posted May 1, 2017 Report Share Posted May 1, 2017 14 minutes ago, bbaker480 said: I've got no problem not tearing apart a perfectly good engine for a single part. Atkins Rotary lists a 12A front cover (used but repainted) for $85. https://www.atkinsrotary.com/store/79-85-12A-Rx7-Reconditioned-Front-Cover-1480-10-600C.html. I can pick up the oil pan there as well, same price range as Ebay. I assume I need the baffle and gasket for the GSLSE oil pan as well? I ordered new bushings for the idler arm, is the Moog part itself different? I think they were pretty cheap as well but I didn't see how the arm itself could be bad. The Moog idler arm is a completely different design, there are no bushings the pivot is basically another ball joint. It is all metal and completely unaffected by heat, last year we ran 17 hrs at VIR with a cracked header which was roasting everything else in the car, the Moog idler arm came through with nothing more than a melted rubber boot. With the stock idler arm the plastic bushings are a consumable and only last so long when subjected to the heat coming from the header of an endurance racing rotary. I see you have a heat shield around your arm but the Moog will live forever without it. Mazdatrix sells them for like $110 but Rockauto and Amazon have them for about $45. Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted May 1, 2017 Author Report Share Posted May 1, 2017 That is a sweet tip! How many gph do you guys use? We were around 7 in the2nd gen. I assume about the same.... Quote Link to comment Share on other sites More sharing options...
mhr650 Posted May 1, 2017 Report Share Posted May 1, 2017 I wish.... Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted May 2, 2017 Author Report Share Posted May 2, 2017 2 hours ago, mhr650 said: I wish.... Are you running stock ports and fuel system? Quote Link to comment Share on other sites More sharing options...
wvumtnbkr Posted May 2, 2017 Author Report Share Posted May 2, 2017 I gathered all of the 2nd gen parts in the 1st gen side of the garage last night. We need to figure out where to put the battery once this is all done. I found all the 2nd gen coils, AFM, MAP sensor, 02 sensor, wiring harness, car side harness, etc.... I know Bryan ordered the stuff for the fuel surge system. Now just to order the 12A to 13B parts and we can assemble. I only have a few items I can work on with the 2nd gen for now. I would love to continue tearing into this thing to get it in Race shape! Quote Link to comment Share on other sites More sharing options...
mhr650 Posted May 2, 2017 Report Share Posted May 2, 2017 17 hours ago, wvumtnbkr said: Are you running stock ports and fuel system? I have never run with exactly the combination that you will be using. I started with the GSL-SE fuel system with 2 injectors even though I was running the larger S4 intake, from there I went straight to S5 and MS3Pro standalone ECU. The standard Mazda ECU is notorious for going very rich at high RPM, the older SE system is probably even worse than what you will have to work with. With the MS I can program good AFR all the way as high as I want to rev the motor, of course if you are making more power and revving the motor higher your fuel burn still goes up even with the proper AFR. In the end I use about the same fuel 8-8.5 gph with both systems I just have a lot more power with the MS. I wish that 18 gallon fuel cells weren’t so expensive to have a little margin to get to 2 hrs if we have to, right now I plan about 1:45 max stints. Quote Link to comment Share on other sites More sharing options...
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