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  • Little Engine, Little Tires, Little Nitrous...

    .
    UPDATES- pages 3 and 4 now contain some pics and updates on my scratch built bellhousing project for the car...
    .


    I always liked '60's Gassers, and decided to start building a modern day version. My RX-7 is a 1985 model picked up for about $50. I had driven it for years with a V8, but got bored and decided to shake things up a bit. These cars are pretty cheap these days, almost free when they have a blown rotary engine. You can still cut one up without feeling too bad. Here's how this one started...



    Looks pretty radical, but it's not that hard. Basically everything between the stock sheetmetal subframe connectors was removed, all the way up to the base of the windshield. Most of it was done with a sawzall and 4" angle grinder. With a little more work, a Viper V10 would fit. Need room for a Turbo?



    The tunnel that was cut out had 9-1/2" trimmed from the rear edge, then it was re-installed. Simple flat panels made from 18ga steel fill in the resulting gaps on the sides. The rotary engine's eccentric shaft (crankshaft) is up in the middle of the rotary engine, so it's transmission sits higher than usual The result is a huge transmission tunnel with plenty of room for most anything including a T56 6 spd.



    Here's the mockup engine in place. I moved it back as far as possible while still being able to wiggle the SBC's distributor past the forward edge of the original windshield. The engine now sits 10" farther back than it's original position. The RX-7's stock wheelbase is only 95".



    Here's the re-located and lightened dash structure before the cover was added. The steering column and pedal assembly/pushrods were extended 7" rearward.



    With the engine farther back, the stock front suspension and crossmember was exposed. I decided to build something that better fit the character of the car...



    Much lighter, and looks like it belongs there. The new front crossmember now doubles as a lower radiator support. The new front motor plates are from a 410 Sprint Car.



    Even the water pump is now behind the front axle. I used to race Outlaw Dirt Latemodels, and much of the engine combination consists of leftovers from that. Old Brodix spread port heads and a .650 lift solid roller, combined w/ flat tops and pump gas. I think the most expensive single part on this car may be the shift lite. I drive the 170mi to/from the track, much of it on the freeway.



    Here's where my screen name "weedburner" comes from, probably not what you were thinking. When the blockoff plates are removed from the collectors, short 3" extensions are added, which feature a "tongue" that extends up into the collector to seal off the exhaust pipes.



    I re-drilled the stock RX-7 front hubs to 5 on 4-3/4". The front struts are re-buildable and have been modified to "90/10" type valving and lighter 100lbs/in springs and adjustable spring seats have been added as well.



    Even on 95 degree days, the car still runs 185 degrees just like this. I was going to build a carbon fibre duct from the nose to the rad, but now i don't think i will bother.



    The engine now sits back far enough that the weight distribution varies between 47/53 to as much as 43/57 depending on fuel load and rear bumper weight. The car's base weight is now 2330lbs. I have an optional rear bumper that has 95lbs of lead hidden inside. No added chassis stiffening at all, as these cars come from the factory with subframe connectors.



    Looks pretty good just like this, but like i said, I like gassers. Next year I may add one of my 6-71's and a straight axle.



    The tires are M/T radials, 275/60-15 in the rear on a 15x8 wheel w/ 5-1/2" backspace. It's absolutely the biggest tire that will fit the stock wheel opening without cutting sheetmetal...



    ...uses all the room inside too. Kevlar lined rod ends are used everywhere in the rear suspension to eliminate any extra side/side movement.



    Here you can see some of the custom Torque Arm rear suspension. A narrowed 8.5" 10 bolt w/ a locker and 3.73 gears as well. The giant Magneflow muffler had to be notched to clear the tire. I wanted the car as quiet as possible when it's out testing on deserted county roads.



    Even with the dash moved back, it still looks kinda stock. I plan to build some aluminum seal panels to fill the areas between the dash and cowl, but I currently drive it to the track just like this. The seats were moved back 6" and down (removed the slider mech), making more room so my helmet doesn't touch the roof. With the steering column extended 7", seats back 6", and the engine/trans back 10", ergonomics are actually better than stock for my 6' frame.



    When the stock carpets get re-dyed and installed, it shouldn't attract too much attention. I need to add power windows though, as the stock window cranks are now partially hidded by the re-located dash...the doors have to be opened to roll the windows up/down.



    You don't need to cut one up at all to fit a V8, as there is plenty of room without changing a thing. Here's a before with the same V8 and after shot with the old air cleaner in place for comparison. Same engine/radiator/hoses/etc, just moved 'em back.


  • #2
    Re: My V8 powered RX-7 street toy

    WOW! Nice work Burner!!!


    And welcome to the forum
    A.K.A. Brian
    Jack of many trades-master of none

    Comment


    • #3
      Re: My V8 powered RX-7 street toy

      :o :o :o Dude, that is RIDICOLOUS!! And I mean that in a very impressed way!

      How's the seating for someone in the 6ft range? How hard is it to keep the front wheels on the ground? Plan on autocrossing it at all?
      Escaped on a technicality.

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      • #4
        Re: My V8 powered RX-7 street toy

        Welcome - NICE WORK!

        That thing has got to FLY 8)
        There's always something new to learn.

        Comment


        • #5
          Re: My V8 powered RX-7 street toy

          Nice car, interested in seeing how the gasser look works on this car.
          Neal

          Drag Week 2010, 2011, 2012, 2013

          Comment


          • #6
            Re: My V8 powered RX-7 street toy

            As we said in my youth - GROOVY! Great build and nice work. Is the hood a commercially available part?

            Dan

            Comment


            • #7
              Re: My V8 powered RX-7 street toy

              nice work, those headers are a work of art.
              Doing it all wrong since 1966

              Comment


              • #8
                Re: My V8 powered RX-7 street toy

                Originally posted by TheSilverBuick
                :o :o :o Dude, that is RIDICOLOUS!! And I mean that in a very impressed way!

                How's the seating for someone in the 6ft range? How hard is it to keep the front wheels on the ground? Plan on autocrossing it at all?
                Thanks for the welcome, guys.
                I'm 6' myself, and ergonomics are actually better. Seats are lowered too, more room for my helmet.
                I'm not much of an autocross guy, but it could be done. Besides the typical changes such as tires/sway bars/springs/shocks, i would also add brake floaters to it to remove the brake hop from the 36" long torque arm.

                Comment


                • #9
                  Re: My V8 powered RX-7 street toy

                  Originally posted by DanStokes
                  As we said in my youth - GROOVY! Great build and nice work. Is the hood a commercially available part?

                  Dan
                  Thanks.
                  There is a guy in Florida that had a good looking hood that he and a buddy made. I wanted one too, so i had him make me 3 to make it worth his while, (2) 3" cowl and (1) 5" cowl. I tried 'em all and decided to use one of the 3" on my car and sold the rest. He still makes a few now and then. PM me if you would like his name and #

                  Comment


                  • #10
                    Re: My V8 powered RX-7 street toy

                    Originally posted by Buickguy
                    nice work, those headers are a work of art.
                    The guy that builds my headers is a semi-retired friend that was one of Doug Thorley's first employees. I can build headers too, but I like to keep him busy if I can. He worked on a lot of famous cars and has lots of stories about going to the drags nearly every weekend in the '60s/70's. I like to learn anything I can from watching him work, but love to hear the stories too. The other day he had seen an article on the Howard Cams "Twin Bears" resto. He remembers being there when it ran and old man Howard reeming the driver for not holding it wide open the full run. They rigged up a big lite on top of the car that was wired to a full throttle switch so the old man could see if it was wide open or not. The lite stayed on the full run, but the old man still did not believe it.

                    He made the headers and I tapped into the collectors and did the exhaust routing and muffler work. Two 2-1/2" pipes merged into a single 3-1/2" out the back.

                    Comment


                    • #11
                      Re: My V8 powered RX-7 street toy

                      Holy superior fabrication skills Batman! amazing work. You said you drive it to the track..what kind of numbers are you running?
                      If you can leave two black stripes from the exit of one corner to the braking zone of the next, you have enough horsepower. - Mark Donohue

                      Comment


                      • #12
                        Re: My V8 powered RX-7 street toy

                        Weedburner, I have two words for you: (1) Brilliant, and (2) clean!

                        I love it!

                        Where are you from, and where did you race dirt?

                        Comment


                        • #13
                          Re: My V8 powered RX-7 street toy

                          Originally posted by chryco63
                          Weedburner, I have two words for you: (1) Brilliant, and (2) clean!

                          I love it!

                          Where are you from, and where did you race dirt?
                          Home track was Skagit Speedway in Alger, WA
                          Here's a link to some of my unusual Dirt Late Models... http://grannys.tripod.com/4rotor.html

                          Comment


                          • #14
                            Re: My V8 powered RX-7 street toy

                            Fantastic car, and I love your name too. ;D
                            President, Wicked Rides Poland

                            http://www.bangshift.com/forum/showt...eau-Club-Wagon

                            Comment


                            • #15
                              Re: My V8 powered RX-7 street toy

                              Amazing work and car, Weed. How fast does it run?
                              BS'er formally known as Rebeldryver

                              Resident Instigator

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