1G Road Racing Weaknesses

Posted by neoviper, Feb 28, 2008
Road Course & Autocross - Autocross, Road Race, and Open Track Event discussions. Preparation, technique, tips, and stories from the events. Tell us about your last event.

  1. neoviper

    neoviper Proven Member

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    I want to build my car to compete in road racing. I've been dooing alot of research lately trying to get as much info as possible so I can plan the build of my car. I've been having a hard time finding a clear answer on some of the downsides of the 1g's design. I am NOT talking about anything that has to do with the engine ( theres tons of facts as well as opinions on that ), but I am interested in finding out the weak points of the other areas of the car.

    Here's what I have so far:

    - The chassis flexes alot and needs to be made more rigid. Obviously a roll cage is a good way to correct this as well as strut braces. I've also read that there is a type of foam or epoxy or something that can be injected into the chasis to stiffen it up (I've read a few threads on this and am still debating whether or not its worth it. maybe someone who's had experiance with it can comment.)

    - The 2g suspension is a better design than the 1g. I'm not sure exactly what makes it better (still have alot to learn about suspension). Is it that the 1g's suspension is a bad design, or is it just not as good as the 2g's?

    - The open differential in the front kills us with understeer. A Quafe differential solves that, but I'd like to know what your guys opinion is on changing the center differential as well.

    - The 1GA's have those puny mickey mouse brakes in the front (mine are already changed to 3000gt's)

    - The car is a pig by nature, weight is a problem.


    Is there anything else that you guys can come up with? I'm hoping for all the road racers to share there personal experiance in this. What have you guys noticed are the weaknesses of a 1g car for road racing?
    #1
  2. eclipsegsx1736

    eclipsegsx1736 Supporting VIP

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    I'll chime in first and add a few things.

    1. The 1g and 2g chassis' are weak and have quite a bit of flex, like you said a rollcage is a pretty good way to help this. Not too much data on foam filling though.

    2. 1g suspension is a McPherson setup which is crappy. 2g's get double wishbone, which is the best suspension a car can have (look at F1 cars, this is basically what they use). McPherson CAN work well though, but the geometry is inferior to others. Both the 1g and 2g obviously are undersprung and underdamped from the factory. Besides stiffer shocks/springs and swaybars (add a rear only first, then add a front if you still need it), the stock bushings are very weak and should be changed out for a full urethane kit (energy suspension or Prothane).

    3. Very few people upgrade the diffs on AWD DSMs especially for road racing. More for Auto-x. Road racing speeds are high enough that you won't be spinning the inside tire that bad. That said, a Torsen type like the Quaife WILL improve power-on grip, but will hurt you when off-power. The LSD doesn't spin freely when off power. Not much info on changing the center diff out on AWD DSMs.

    4/5. Looks like you got that covered and what you need to do. In fact, looks like you got most of this pretty well researched.

    Obviously cooling issues are a problem too (remove your A/C at least, bigger radiator, better ducting, avoid a FMIC if possible or get one that flows through itself well) but we're talking suspension-only issues. 1g's also have the active toe which should be eliminated. If you do all this, along with the obvious things like wider wheels and tires, camber settings, etc you'll have a hell of a car.
    #2
  3. absolute_DSM

    absolute_DSM Proven Member

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    Remember to build the car for the class you plan to compete in! Id hate to see you mod the car enough it moved you up to the top competing against race trim Corvettes.... :cool:
    #3
  4. E Racer X

    E Racer X Proven Member

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    I would suggest upgrading the oil cooler on the 91-94 1G. Excessive oil temps can hinder performance and contribute to engine wear. There are a few companies out there that offer FMOC kits, here's an example: Automoto Sports Copyright&copy AMS 2006

    Best of luck with your new venture!
    #4
  5. talonTSIDriver

    talonTSIDriver Proven Member

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    I don't mean to burst your bubble, but I would strongly recommend learning auto-X prior to stepping into the FULL open track days. I don't really know your history with racing, but auto-x should be the first step before open track days.
    Last edited by a moderator: Jun 5, 2014
    #5
  6. talonTSIDriver

    talonTSIDriver Proven Member

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    What about for a 7 bolt???
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  7. tsiboosted

    tsiboosted <a href=/forums/blogs/tsiboosted/race-reports/>DSM

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    Good point there Andy. Not only the experience, but the cost factor as well. $20 usually for AutoX. Most open track days are around $200 and up from my experiences.

    And for the 7 bolt, couldnt you just get that kit (minus '90 housing & the $70) and get an Evo oil housing? Isnt that the one you use for the 7 bolt? I could have swore I read that somewhere. Could be wrong there though. Andy, you would know better than I on that issue I'm sure.
    Last edited by a moderator: Jun 5, 2014
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  8. talonTSIDriver

    talonTSIDriver Proven Member

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    you may be right on the oil cooler for a 7 bolt. I'll be reading in on it.

    neoviper: what sort of experience do you have with road-racing?
    #8
  9. Dave532

    Dave532 Proven Member

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    The 1G suspension has some advantages over the 2G and vice versa. For example, it easier and quicker to change spring rates in a 1G and it can withstand much more abuse (rally racing). The 2G suspension, however, has greater potential for pure asphalt racing.

    Almost all cars need bigger brakes when road racing and the DSM is no exception. The cool thing is that you have numerous options.

    My most difficult issue road racing a 1G is the fuel pickup problem. On high G left handers, the fuel moves to the right inside the tank while the fuel pump (installed on the left) runs dry. There are ways to minimize the problem but to fully cure it requires some mods and a bit of money. Just something to keep in mind if you experience fuel cut once you are on some grippy tires.
    I don't know if the 2G experiences this issue.

    Both cars have the crankshaft on the driver's side (worst side) and in front of the axle line (worst end) so the weight distribution is horrible...you can alleviate some of this problem but it will always be there in some aspect.

    But I digress...I personally like racing a 1G but I have never had the pleasure of owning a 2G so I cant speak on it.

    Oh, one more thing...
    IMO, race only what you can afford to destroy
    #9
  10. tsiboosted

    tsiboosted <a href=/forums/blogs/tsiboosted/race-reports/>DSM

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    Yes, the 2G's have that same issue as well. Only solution (real solution) is of course a fuel cell. But they cost a pretty penny. Other solution is obviously some foam in the tank (which may or may not be legal) and a surge tank with another pump. I personally right now have to run a full, or close to full tank to keep this from happeneing after 20 minutes or so on the course. Which is a lot of excess weight to be hauling around for almost no reason.

    And I like your "Race only what you can afford to destroy quote". :thumb:
    #10
  11. neoviper

    neoviper Proven Member

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    Your not bursting my bubble, your absolutely right. I'm gonna be moving to georgia in a few months and my cousin who lives there says they run a ton of auto-x events over there. I'm planning on running alot of those to get my feet wet. I also plan on getting some seat time in some HPDE events. I was just trying to get an idea of some of the flaws in the cars design so I had a better idea of what kind of work I had to do. Thanx for all the advice!:thumb:
    #11
  12. neoviper

    neoviper Proven Member

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    Im as green as they come.:p I've just read up on it alot.
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  13. talonTSIDriver

    talonTSIDriver Proven Member

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    Fuel Cut is not caused by low fuel pressure, its caused by the ECU reading too much air coming through the MAF and then cuts the fuel as a safety precaution to the engine.

    Reading a lot will help a lot. Another thing that helps a lot is practice (AKA SEAT TIME)
    #13
  14. Dave532

    Dave532 Proven Member

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    Not to jack this thread...

    Eddie, I have an idea you can try that is cheap and relatively
    easy which will allow you to keep less fuel in the tank. I will PM you.
    #14
  15. E Racer X

    E Racer X Proven Member

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    I politely disagree. I believe you should try a track day and go out with an instructor and take it easy, learn the car and proper approaches and procedures. I've never participated in an auto-cross with my Galant but I have been to the road course.

    That's a great question. As far as I know you need the oil filter housing from an EVO III for it to work with a 7-bolt DSM 4G63. I believe those are very hard to come by.
    #15
  16. talonTSIDriver

    talonTSIDriver Proven Member

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    I'd be more concerned about the money factor. For the price of one lapping day at a big track, you could attend an entire season of auto-x events. This sport is already expensive, money management is crucial. If money was truly not an issue, then I’d say, sure, why not go out and learn on a large road course, just as long as you learn the right way (like you said, ride with an instructor).
    #16
  17. tsiboosted

    tsiboosted <a href=/forums/blogs/tsiboosted/race-reports/>DSM

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    I believe that is the one I was referring to. Thanks. :thumb:

    Thanks Dave532.
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  18. neoviper

    neoviper Proven Member

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  19. E Racer X

    E Racer X Proven Member

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    A great way to combat this would be a fuel surge tank. You can modify the fuel sending unit and utilize your in-tank pump while running an inline Walbro 255 lph. The 2G gas tank is designed and positioned more thoughtfully than the 1G but it can produce the same starving issues. I think a surge tank would be a great option for either generation. You can run less fuel (lighter vehicle) and avoid fuel starvation.
    #19
  20. talonTSIDriver

    talonTSIDriver Proven Member

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    save money, run a full tank. :D
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  21. neoviper

    neoviper Proven Member

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    Thats exactly what I had in mind. Don't get me wrong I do plan on getting seat time with an instructor, but money management is CRUCIAL. With all the maintainence involved and the occasional mod here and there ( as I can afford them, they come )It makes more sense for me to run as many auto-x events as I can.

    But I will ride with an instructor every chance I get.
    #21
  22. mavisky

    mavisky DSM Wiseman

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    On a nearly stock car, stock equipment in good condition should be fine.

    Are you just wanting to run HPDE's? Run in time trial events? or run door to door in an actual racing class?
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  23. talonTSIDriver

    talonTSIDriver Proven Member

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    You got it! First year you will learn A LOT!! I bet your mod plans will change as well. You sound like your on the right track. I am sure you'll do great! :thumb:
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  24. neoviper

    neoviper Proven Member

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    HPDE First, Than i'll compete in some time trial events (no sense making myself look bad until I can put up respectable times:thumb:) and than if I'm not bankrupt by than I want to go full all out door to door racing (not sure what class though, thats in the future so I have plenty of time to think about that)
    #24
  25. mavisky

    mavisky DSM Wiseman

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    Well you'll have to do your HPDE's before they'll let you do any time trials. Just keep in mind what classes you may want to run in and make sure to modify your car within those limits.
    #25

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