GrabberGT Ev. 5

Discussion in 'Maverick/Comet Projects' started by GrabberGT, Apr 10, 2009.

  1. GrabberGT

    GrabberGT Chris

    Joined:
    Sep 22, 2003
    Messages:
    1,626
    Likes Received:
    137
    Trophy Points:
    167
    Location:
    Fort Worth Texas
    Vehicle:
    72 Grabber 302
    Alright. The first Autocross is out of the way. The car survived... I think. Let me get under it and inspect everything to make sure. I took a ride with someone else first and thought that there was no way my car was going to take that kind of punishment. Its absolutely brutal on the car. But sure enough, when it was my turn, the car handled it like a champ. Even with my pitiful driving it still survived. I imprived my time from a 45.88 to a 41.80 in the 6 runs I got in. I never got out of first gear the entire time though it would have been possible to run it in second with a decent launch. My front end want to plow thru most of the turns. I REALLY need that 1.25" sway bar.

    I couple problems I encounterd...

    -Car dies under extreme braking. I was told that there is a Jet Shroud that is meant to shroud the jets under braking to keep the carb from starving for fuel hard on the brakes.

    -Tires just dont want to hold. I need a more performance oriented tire. I must have had the highest treadware rating out of 60 cars.

    -Sway bar. I really need more.

    _transmission. Big reason I didnt shift into second was because my transmission just doesnt want to. Its hard to throw it into any gear with any kind of speed and even worse when down shifting. It actually got to the point that I couldnt shift into reverse at all. Maybe the heat from the headers is causing problems for the hydraulic fluid.

    -Brakes. My breaks work great ONCE. But at the end of a run I've lost half of my brake pedal. I've actually forgotten about this. I also have this problem when at the drag strip but thought it was related to using my line lock. Apperently not. I know my rear needs more brake bias which I'll fix as soon as I can get an adjuster ordered but other than that, I dont know what to do. Someone mentioned that maybe I have water in my brake lines that when it boils leaves steam that compresses where the fluid doesnt. Seeing that I hardly even touched the brakes for the entire run, I dont see how this could be it. It could be break knock-back where the cornering forces use the extreme offset as a wheel to push in the brake pad causing the need to pump the brake pedal to get pressure back to where it is usable. This sounds more like it but it doesnt explain why it happens when drag racing. I'll check my bearing preload anyway to make sure there are no surprises.

    My biggest concern by far though is the transmission. It shouldnt be this much trouble to shift. Its a newly built g-force t-5. anyone have any ideas? I'll try preloading the clutch fork a little to see if it gets any better. I feal a 1" master is in my future.
     
  2. markso125

    markso125 Member

    Joined:
    Aug 19, 2007
    Messages:
    1,714
    Likes Received:
    6
    Trophy Points:
    117
    Location:
    Lewiston Ut
    Vehicle:
    1972 maverick 2 door LDO
    With the clutch issues, I have seen allot of guys using adjustable pivot bolts on the T5 bell housing to help with some of their issues, well either that or they just put a washer or two under their stock pivot ball to move it out, you might want to try that before spending the money on a new MC.

    If we have any more people with transmission issues with G-force gears in them, i might start thinking that their quality is sub par...:hide: (I know they make some pretty good stuff its just interesting seing how both you and Mashori have g-force gears, some of the most prominent ones on this forum with g-force gears, and you both had transmission problems)
     
    Last edited: Sep 25, 2011
  3. mashori

    mashori Member

    Joined:
    Apr 21, 2006
    Messages:
    3,630
    Likes Received:
    2
    Trophy Points:
    0
    Location:
    San Diego, Ca
    Vehicle:
    1971 V8 Maverick
    I don't recall any major problems with G-force, I might have forgotten though. With my car and Bryant's one of us had to be in the car and press the clutch to see when the fork would start moving. When I had similar issues I would be 1-2" off the floor before any movement. In that care it was air in the system. We fixed that and the troubles went away. I have to on occasion put more preload on the clutch fork but screwing out the ball on the slave cylinder but otherwise haven't had any trouble.
     
  4. markso125

    markso125 Member

    Joined:
    Aug 19, 2007
    Messages:
    1,714
    Likes Received:
    6
    Trophy Points:
    117
    Location:
    Lewiston Ut
    Vehicle:
    1972 maverick 2 door LDO
    Nah I was referring to your first set that wasnt properly shimmed and you ended up replacing.:rolleyes:
     
  5. GrabberGT

    GrabberGT Chris

    Joined:
    Sep 22, 2003
    Messages:
    1,626
    Likes Received:
    137
    Trophy Points:
    167
    Location:
    Fort Worth Texas
    Vehicle:
    72 Grabber 302
    There are Jet extensions. I ordered these from Jegs but had trouble installing them. There was no mention of it but apparently you also have to buy the nothced fuel bowl floats in order to install them. I ended up having to live with the car dieing out on the course. Luckily enough, I never had to stop and restart. The car would jump itself off if I just kept it rolling.

    I was able to connect my rear sway bar after hunting down parts all day on Thursday. It helped a bunch. That and getting my tire pressure setup made the biggest difference.

    This was merely a problem with the adjuster nut not staying in place. After adding a couple turns of preload back in, it worked just fine again. The morning of Goodguys though, I again had to tighten it back down. I'll be adding a different style lock nut before long.

    I still want to make some more adjustments to try and minimize the amnt of pedal needed to release the clutch. My legs are long and having to fight for space with the steering wheel when shifting is not ideal. If I cant adjust it down to minimal travel, I'll look in to a 1" master to use.

    Brakes are still a problem. I ran out of time to get the rear break adjuster installed. I dont really think it will make mutch difference but will try it anyway. I didnt have mutch issue at GG due to the constant breaking being done but did notice a couple times a little less pedal than usual.


    Coming up next:

    Finally going to install my EFI. Its time. Hopefully I can get it done over a weekend.

    New wheels/tires

    Bigger brakes

    Dropped spindles

    Larger sway bar

    Lots of little odds and ends to do. All those things that make a car complete. At least thats what I tell the wife. :rolleyes:
     
  6. GrabberGT

    GrabberGT Chris

    Joined:
    Sep 22, 2003
    Messages:
    1,626
    Likes Received:
    137
    Trophy Points:
    167
    Location:
    Fort Worth Texas
    Vehicle:
    72 Grabber 302
    The results are in. Out of a total of 49 entrants, I was 22nd. I can say that only about 4 of them I am embarrassed to admit losing to.

    http://youtu.be/eAmSMv4kuwA
     
  7. Shaun MAVMOD

    Shaun MAVMOD Member

    Joined:
    Apr 24, 2008
    Messages:
    111
    Likes Received:
    0
    Trophy Points:
    60
    Location:
    Surrey BC Canada
    Vehicle:
    2 door 1970 Maverick
    Thanks! for the Video link it was cool to see your Mav in action.
     
  8. mashori

    mashori Member

    Joined:
    Apr 21, 2006
    Messages:
    3,630
    Likes Received:
    2
    Trophy Points:
    0
    Location:
    San Diego, Ca
    Vehicle:
    1971 V8 Maverick
    your car looks great on that track! it looks like it's handling really well with those crazy turns
     
  9. GrabberGT

    GrabberGT Chris

    Joined:
    Sep 22, 2003
    Messages:
    1,626
    Likes Received:
    137
    Trophy Points:
    167
    Location:
    Fort Worth Texas
    Vehicle:
    72 Grabber 302
    Going to the drag strip tonight to see what it will do pre-EFI. I've got my line lock connected and ready to go. Anyone care to guess what it will do? The last time I went, I had the 302, leave springs, and 275 rear tires. It did 8.9 seconds at 91 mph. Now I weigh a little more but have gotten rid of the leafs and should have better traction. Also have changed to a 285 rear tire and a 347. Let me mention that the 347 does not pull like a 347 should. Its down on power so assume I have a really good running 302. With a good 347 right around an 8.0 should be relatively easy but Im going to hope for an 8.50
     
  10. mashori

    mashori Member

    Joined:
    Apr 21, 2006
    Messages:
    3,630
    Likes Received:
    2
    Trophy Points:
    0
    Location:
    San Diego, Ca
    Vehicle:
    1971 V8 Maverick
    oh you'll do better than that!
    I did 8.43 launching at 5K without nitrous
    The 331 with nitrous did 8.23
     
  11. GrabberGT

    GrabberGT Chris

    Joined:
    Sep 22, 2003
    Messages:
    1,626
    Likes Received:
    137
    Trophy Points:
    167
    Location:
    Fort Worth Texas
    Vehicle:
    72 Grabber 302
    Wow! You dropped the clutch at 5 Grand? I cant get any grip out of the hole launching at 2500. I'll play with it tonight and see where I can get. I want to get a time tonight and then after the EFI swap, get another time. I hope to see a huge difference.
     
  12. GrabberGT

    GrabberGT Chris

    Joined:
    Sep 22, 2003
    Messages:
    1,626
    Likes Received:
    137
    Trophy Points:
    167
    Location:
    Fort Worth Texas
    Vehicle:
    72 Grabber 302
    Its worse than I thought. Traction was not a problem. The track was sticky and the suspension did its job. I had trouble getting off the line without bogging down.

    My best time was a 8.97 @ 82.6 mph with a 60ft time of 2.25 . The harder I tried to launch the worse it bogged off the line. I shifted around 5500 - 6000.

    Gearing my be to much for a good launch but really shouldnt be this bad. I have a 2.95 1st and 3.50 rear. I think the motor is just not performing up to its capabilities. I'll slap the EFI on it and see if it helps.
     
  13. blugene

    blugene Senior member Supporting Member

    Joined:
    Jul 25, 2004
    Messages:
    10,758
    Likes Received:
    73
    Trophy Points:
    283
    Garage:
    1
    Location:
    Marietta, OK
    Vehicle:
    73 Comet GT, 72 Comet GT, 2008 "Comet" (our boxer, who is now in the galaxies)
    I remember having higher rpm issues when my secondaries wouldn't produce enough. Just boggs. If I slowly got into it it would be better. I never had any second or third gear burnouts. Once or twice did I get a chirp into second. Course I have an automatic, which was built to shift kinda hard.
    Point is I found issues in carberation, starting with the pump cam.
     
  14. GrabberGT

    GrabberGT Chris

    Joined:
    Sep 22, 2003
    Messages:
    1,626
    Likes Received:
    137
    Trophy Points:
    167
    Location:
    Fort Worth Texas
    Vehicle:
    72 Grabber 302
    I think the bogging is related to my clutch pedal setup. The motor power issues is comb of carb and timing.
     
  15. CaptainComet

    CaptainComet Large Member

    Joined:
    Mar 18, 2007
    Messages:
    4,992
    Likes Received:
    436
    Trophy Points:
    413
    Location:
    Clearwater, FL
    Vehicle:
    72 Comet
    In my opinion, your gearing is spot-on for bracket racing a street car. It should really pull off the line, and you should see first gear go by pretty quick before you need to hit second, but as long as you aren't spinning the tires, I think you will find the gearing really good once you get it sorted out.

    My first impulse says that there is a carb issue, but if the clutch feels off, they are probably both working against you.

    If switching to EFI is the next step, I would not touch the clutch until you make it back to the track. See what a change the EFI makes and you can rule out what the carb might have been doing. :thumbs2:

    ...OR.... tweak the clutch, go back to the track, then try the EFI.... scientific method ... one change at a time, and measure the results.
     

Share This Page