My Comso powered 1st Gen RX7

Discussion in 'That'll Buff Right Out' started by AJC13B, Jul 23, 2001.

  1. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    Here is my baby.

    [​IMG]

    It's an Australian Series 3 RX7 delivered in 1985. Similar to a GSL-SE but with a 12A engine not 13B :(

    Car now has a 13B Cosmo engine that has been ported, dowelled and 3mm composite seals been added to the 13B-REW rotors. Turbo hanging off the side is a hybrid with Garrett T72 front with turbonetics Q trim exhaust blade with a 1.22 divided housing. Air is kept cool via a front mount intercooler that takes up the entire front nose of the car. Fuel is taken care of via 2 Bosch motorsport fuel pumps that pump fuel to 2 850cc primary fuel injectors and 2 1000cc secondary injectors.

    Turbo next to 13B rotor:

    [​IMG]

    General engine bay shot:

    [​IMG]

    The whole lot is kept moving by a Haltech E6K tuned by www.hitman.hm and spark provided by T2 coils.

    Sitting behind the engine is a T2 box with an RE Amemiya twin plate clutch and flywheel.

    Behind that is a 3.5inch custom tailshaft backed by a custom Borg Warner diff with 31 spline billet ally axles, 4.11 LSD centre and thick walled axles tubes.

    Old axle is left, 31 spline on right:

    [​IMG]

    The car rolls on 17x7 front and 17x8 rear FR17 Simmons wheels wrapped in Falken GRB rubber, 205/40/17 front and 225/45/17 rear. The guards had to be lipped slightly on the back to fit, but the front was fine. Shocks are Koni all round and lowered King springs.

    Front rim:

    [​IMG]

    Car is fairly standard inside, well trim anyway! :big grin:
    Car has an Alpine CD head unit, 6.5 inch splits in custom door pods in the front and 6.5 inch co-ax in the factroy spots in the rear. Also has a 10inch sub in an enclosure and its all powered by a V12 amp.

    Door pods:

    [​IMG]

    I turn the wheels with a Momo Champion steering wheel and keep an eye on Omori gauges that monitor oil pressure, water temp and boost pressue and also watch mixtures with a Haltuner. Sitting at home waiting to go in is an Omori Exh. temp gauge.

    [​IMG]
    [​IMG]

    I have built the car to be a tough street car that looks decent and goes hard. I think I have achieved it fairly well.
    Power figures are looking good. On 98RON pump fuel and 12psi, the car made 334rwhp on a dyno dynamics (Dyno Dynamic read approx 17% less than dynojet) and about 19c ambient. On the same night we put C16 and upped the boost to about 20psi. We had 20psi by 4000rpm and 375rwhp by 6000rpm. At 6000rpm we experienced very bad ignition break up. This was later traced back to power loss to the coils. 10v at the coils on a 5000rpm free rev is never a good thing....

    With 15psi or so and pump fuel, I took the car to the track for the first time with slicks (26x8x15) and this set up. Having never raced with slicks before I didn't know what to do. My best 60ft all night was a 1.89! Best ET was a 12.5 at 86mph and a back off at the top of third gear. Best trap speed for the night was 116mph on a 13.0 run with a 2.4 60ft.

    At a latter meet, I dropped my 60fts down to 1.6 but the power loss and general wiring problems prevented the car from doing any good, and a 13.0 was my best time.

    At the moment my car is with one of the guys from Haltech in Sydney getting the ECU re-wired to try and eliminate some problems. When the car hits the road again, it will be tuned for 23-25psi and C16 and taken to the track. Realistic hopes are for a high 10 and I think the car has it in it, it comes down to whether I can drive it to a 10 or not :)

    Hope you like.

    Steve
     
  2. Short Bus

    Short Bus Beep beep!

    Joined:
    Apr 17, 2001
    Messages:
    104,725
    Likes Received:
    0
    Damn, um...

    ...I don't know what to say, you have a beautiful car. :) I've seen it on the RX-7 forum a few times.

    I'd love to do what you did to an old FB, but I'm afraid I'm lacking a bit in the knowledge area.
     
  3. about:blank

    about:blank Whether you think that you can or that you can't,

    Joined:
    Apr 5, 2001
    Messages:
    28,240
    Likes Received:
    26
    Location:
    Portland/Charlotte
    Eww, that's ugly... Oh wait, pictures are loading... DAMN!! :eek: :bigthumb:
     
  4. eurodeseo

    eurodeseo The asshole of your dreams

    Joined:
    Oct 31, 2000
    Messages:
    1,347
    Likes Received:
    0
    Location:
    OH
  5. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    Thanks guys!

    Short Bus> Its not that hard to get something like this! Just do it right and only listen to ONE person when building a car! If you listen to everybody, you will get confused and make a mistake!
     
  6. Diablow

    Diablow Guest

    oh man that is so nice :cool:
     
  7. djraid619

    djraid619 Guest

    13b Cosmo Engine . . . gah! One word . . . NICE!
     
  8. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    :bigok:

    Thanks guys, you rawk!!
     
  9. Short Bus

    Short Bus Beep beep!

    Joined:
    Apr 17, 2001
    Messages:
    104,725
    Likes Received:
    0
    Now all I have to do is figure out who that one person is that I should be talking to. :big grin: My convertible could use one of them there turbo-majigs ya got there. :)
     
  10. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    Well it depends on how much you want to spend! My engine bay along owes me over $15000AUD!

    Best bet would be to speak to some people on the RX7 forum from your area and seewaht they say about the local tuners, see if they are any good. If they are, go seem them! Let them know how much you have and what you would like and they will put something together for you!

    If you have any questions, let me know!
     
  11. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    Short bus> I asked my engine builder for approx prices for my setup. I am good friends with him so I got prices cheaper :bigthumb:

    All prices are in Australian dollars. For USD, half it and add a little bit.

    Engine is $3000 for an import.

    Cost for a rebuild is $2500, but I had special apex seals and dowelling which adds up to about $3200 for the rebuild.

    Turbo and wastegate plus custom SS manifold is worth about $3000. Exhaust is 3 SS inch straight off the back of the turbo, 3 inch cat convertor, 3 inch straight through resonator and 3 inch straight through muffler. Had a noise test done on it and it got 89db at 4000rpm! :bigthumb: Cost would be around the $700 mark.

    Intercooler is non polished (who is going to see it?) and is worth $1800 add another $200 for the stainless intercooler piping (2.5 inch from turbo to intercooler and 3 inch from intercooler to throttle)

    Clutch is worth $3000 new and T2 box about $700. I had a 4 puck sprung brass clutch and 1 tonne pressure plate with this setup and I had destroyed it within a month on street tyres.

    Now labour to throw all this in your car would add up to a fair bit.

    On top of all that you have a Haltech E6K with flying loom and connector kit would add up to about $2000 initially and thats if you wire it yourself. Tuning depends on what your local guy can do, usually $100 an hour??
    I run T2 coils and they throw some MEAN spark, stay away from the MSD stuff, waste of money. T2 coild are around $400 for the pair.

    Thats about it really! I think I covered everything in there! ANy questions, let me know.

    :bigthumb:
     
  12. matt

    matt Active Member

    Joined:
    Aug 29, 2000
    Messages:
    11,843
    Likes Received:
    0
    Location:
    huntersville, nc
    Crazy Aussies and your silly rotors.

    :bigthumb:
     
  13. C4

    C4 OT OG Aussie #1

    Joined:
    May 23, 2000
    Messages:
    30,846
    Likes Received:
    2
    Location:
    Sydney, Australia
    :FAWK:
     
  14. Short Bus

    Short Bus Beep beep!

    Joined:
    Apr 17, 2001
    Messages:
    104,725
    Likes Received:
    0
    I'm pretty much on my own out here as far as rotary support is concerned. :( The nearest thing is a 2 1/2 hour drive to Atlanta, which isn't too bad I suppose, probably worth a call. I do my own wrenching so the labor would all be taken care of by myself.

    I've done a lot of studying and I've got a good idea what I'm going to need in order to complete something like that. It's just that I'm wondering if it would be worth $10k U.S. to convert the car I have, or just buy a Turbo II and go from there.

    Here's how I have it broken down for the conversion, all prices are U.S...

    $1000 for Jap spec used engine (no porting, initially)
    $700 (not sure) for tranny, driveshaft, diff, and half-shafts
    $2500 for a T04E turbo
    $300 for a cast turbo manifold, not sure of my options here
    ~$500 for a nice wastegate
    ~$200 for a BOV
    ~$1500 for intercooler and piping
    $1500 for Haltech ECU
    $500 for various fuel system pieces
    $1000 for exhaust system
    $500 for a lightweight flywheel
    $500 (probably more) for a decent clutch, not sure what I'd go with yet
    $1000 for shipping and various other little things not covered above

    $10200 for everything listed.

    I'm sure I left a few things out, but that's my basic breakdown of what I'd need to do the swap. I know with all that I'd sorta be going balls out on it, I could make it work with the stock ECU, turbo, intercooler, exhaust, flywheel, etc, etc., but if I'm going through the trouble, I'm gonna do it right the first time.

    My other option, which is more desireable to me because as much as I like my car, I get a little nervous when I think about having that much power in a convertible, is to go buy a Turbo II and mod it out a little at a time. The problem is that if I buy a Turbo II it will have to be in pristine perfect shape, which is hard to find.

    I've got some time to think about it, it'll be at least until January before I have enough money to do anything at all.
     
  15. Short Bus

    Short Bus Beep beep!

    Joined:
    Apr 17, 2001
    Messages:
    104,725
    Likes Received:
    0
    Oh, one question.

    Why do you say what you say about the MSD ignitions? I know the stock system is pretty capable by itself, but what's wrong with using an aftermarket ignition?
     
  16. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    Why pay extra for something thats not needed?
     
  17. Short Bus

    Short Bus Beep beep!

    Joined:
    Apr 17, 2001
    Messages:
    104,725
    Likes Received:
    0
    Good point. :)
     
  18. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    ~bump~
     
  19. Big James

    Big James Guest

    Hands down, the best 1st gen I have ever seen.
     
  20. twin_turborx7

    twin_turborx7 Sponsor: DeeperImage.com

    Joined:
    Sep 15, 2000
    Messages:
    2,136
    Likes Received:
    0
    Location:
    Atlanta, GA. USA
  21. Guest

    Guest Guest

    What can I say that hasn't been said before? Sweet...I'm jealous.
     
  22. ProjectGSX

    ProjectGSX Guest

    I have to agree, that is a pretty sick car. :) Nice work!
     
  23. Guest

    Guest Guest

    Wow! Hate to run into that on the highway....
     
  24. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    A long overdue update on the car...

    Secondary injectors are now 1650cc.

    Box is now an early 2nd gen box (seems to have shorter ratios) and a custom made quick shift.

    Car has been back on the dyno and some good numbers pulled out of it :)

    On 98RON pump fuel and 14-15psi, we got 410rwhp out of it.

    On C16 and 22psi, we got 510rwhp.

    A few days later the car was taken to a drag meet and ran the following times:

    The first pass was an 11.4 @ 124mph with a 1.8 60ft.
    2nd pass was an 11.4 @ 122mph.
    3rd pass was an 11.2 @ 122mph.
    4th pass was an 11.1 @ 125mph!!!
    Last 3 passes all had 1.6x 60ft times.

    I had boost problems that was traced to 2 vacuum lines being blown off the manifold! The mixtures were left rich for safety and now my engine builder has told HITman it is kay to pull fuel out of it.

    I am also going to put a smaller back on the turbo. The 1.22 comes on too late, like around 4500-5000rpm. This is no good for the track and REALLY not good for the street! So I am going to a local turbo guru to see what he has to say.

    When the car hits the track again early next year, it should run a 10 standing on its head. I would like a 10.5 at 130+mph. It has the HP, does it have the suspension and driver to do it? Time will tell...

    PS Thanks for all the great comments on the car! :bigthumb:
     
  25. AJC13B

    AJC13B Whats a nubian?

    Joined:
    Apr 27, 2001
    Messages:
    6,687
    Likes Received:
    0
    Location:
    Sydney, Australia
    Another update!

    Car made around 500rwhp on 22psi and 98octane pump fuel at around 1900ft elevation at a dyno shoot out. I came first! :bigthumb:
     

Share This Page