Posted By: Thumperdart
I THINK WE`RE ON TO SOMETHING............. - 02/27/09 05:53 PM
If you`ve seen/heard my vid this pig is laying over in high gear.....I checked flash stall yesturday in 3rd and it flashes bet 4000-4500rpm`s so that seems ok. After thinking about it and talking to my machinest,I`m going to check my valve springs and see how they look and (for now) shim em up to get back my pressures since they`re 4+ years old w/LOTS of street miles. Hopefull that`s the reason it`s laying over if not, we`ll try something else. Thankxx 4 listning.
Posted By: BLACKFISH
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 06:02 PM
Just like to say that your car fascinates me. Great to see a budget minded car run so good at the track and on the street.
Far more interesting than hearing about the 6 and 7 second so called street cars that can't make a trip to the track without overheating and rocker issues. Keep up the good work 9.80's are in the near future.
Posted By: boatracer572
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 06:07 PM
I would check the pressure of the valve springs and If Its low I would disgard ,buy, and install a new set! shiming a set of valve springs is just a cheap bandade in my eyes!valve spring are very inexpensive compared to what they can cause for damage!
Posted By: Anonymous
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 06:08 PM
it sure can't hurt to check the springs but, don't you think if they were an issue, you would notice float in 1st and 2nd gear also?
Posted By: Dragula
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 06:23 PM
Ditto...
I would be looking at a fuel supply issue on the big end. I have had it, as well as many of my friends. Pump might say 140gph, yet you will find, it just might not be enough.
I had a 340 car with 3/8" fuel line and such, jetting changes made no difference in mph, car would not climb much past 1/8 in high gear only. It had a holley blue on it. I put a second one inline with the first....From one pump right into the other and up to the carb. I dropped 10 jet sizes, and mph picked up big time.
Posted By: RUNCHARGER
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 06:50 PM
Do you have a fuel gauge that you can read in high gear?
Sheldon
Posted By: Thumperdart
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 07:18 PM
I just assumed it mattered more in high gear than down low since the motors loaded most in high gear.
It could be fuel related but I figured if I shimmed up the springs and it picked up, then I`d put new springs on+ people have been shimming for years w/out issues. This thing 1/8th miles great that`s ANOTHER reason for my goofy thaughts.
Posted By: Thumperdart
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 07:34 PM
I do have a guage but, my dumb a$$ didn`t look to see where it was at.
Posted By: TheBlackCar
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 07:59 PM
If you short shift car and ET stays same or improves, replace valve springs. Also, if it has a roller cam, pull cam and look at it, if springs are weak you will see where the lifter is landing on the backside flank.(jumping the lobe) In which case, thats why most people have lifter issues, the wheel splits after a while. As long as you claim the the springs have been in there, they are more than likely shot, unless you back off the rockers when car sits.
As for the fuel possibilities, if you keep throwing jet at the carb to satisfy top end plug reading and the bottom end numbers start to falter, its fuel volume. Good Luck
Posted By: Thumperdart
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 08:21 PM
Thankxx.....I`m no expert by any means and am open to all suggestions.
It`s possibly a combinatin of ALL the above as this thing has hundreds of street miles w/open pressures bet 580-600lbs and closed #`s around 260-280. I`ll flow my pump again at the new 9 lbs. and see how long it takes to get a gal.
Posted By: Anonymous
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 08:29 PM
Quote:
Thankxx.....I`m no expert by any means and am open to all suggestions. It`s possibly a combinatin of ALL the above as this thing has hundreds of street miles w/open pressures bet 580-600lbs and closed #`s around 260-280. I`ll flow my pump again at the new 9 lbs. and see how long it takes to get a gal.
with an adequate pump you don't need 9 lbs of fuel pressure. volume is the key thing. if your raising fuel pressure and the e.t. improves, you need more volume.
raising the pressure is nothing more than a band-aid. 7.5 lbs should me more than enough pressure if you have enough pump and proper sized fuel lines.
Posted By: WadeMetzinger
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 08:33 PM
If it's fuel delivery or shortage and that's what it sounds like to me you better get out of it quick or you'll melt spark plugs and pistons, I speak from experience....
Posted By: 493_DART
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 09:25 PM
hey Thump, for the heck of it, find that torque converter slippage calculator , and punch in your numbers.
Mine came out 13% slippage ... no wonder my car is super lazy on the top end
Posted By: Thumperdart
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 09:49 PM
I didn`t look at my tach through the stripe so I don`t know where I was at. In the past if I remember correctly, I went 10.13 @ 132+ w/4.11`s at 6800-7000 rpm`s if that helps.
Posted By: Bob_Coomer
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 10:07 PM
The MPH is right were it suppose to be given the E/T. At least it is on the cars/trucks I have built.
Posted By: Thumperdart
Re: I THINK WE`RE ON TO SOMETHING............. - 02/27/09 10:50 PM
Punching in my stats gave me 9.79%......
?
Posted By: 66er
Re: I THINK WE`RE ON TO SOMETHING............. - 02/28/09 03:30 PM
How's your ignition system. If it is weak it will show you in high gear. How old are your, cap and rotor, wire, and plugs. I had a simullar problem at the March Meet last year. I cleand the reluctor and pick-up coil on my MSD dist. and the problem went away. How is that for a cheap fix
