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  #16 (permalink)  
Old 09-17-2013, 10:21 AM
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Originally Posted by F-BIRD'88 View Post
Something is killing the top end. Based on the 96 mph in the 1/8th the 1/4 mile MPH should be 120+MPH.
You are loosing 5 MPH and something is killing the top end power at the top of the track.
(fuel flow, lean jetting, High head wind, valve float, (valve springs wrong) excessive rpm.
Auto transmission or torque converter fried.. Clutch fried (manual trans)

Or you took your foot out of it too soon.

Just doing the rough math on a 115MPH and 2880 car weight the engine power calc did seem lame.

This light weight car should be running 120-121 MPH.
is this a auto trans or manual trans car?
rear suspension? Trap RPM? gear ratio? Did you let off the gas early?
Front end way too high thru the traps, trapping air under car, effecting traction, handing and top speed.
And scaring the S**T out of ya. Did you let off?

Car has a G force 4 speed manual trams with a McLeod twin disc clutch. Rear suspension is coil over / ladder bar setup. Trap rpm is around 6300 rpm. With the front end limited the car handle great at 115mph. It was to the floor through the traps.

Maybe some useful info : car goes theough the traps at 6300 in 3 rd though. Rear gear is 4:11. I had an alternator alignment issue combined with a leaky rad cap. When I ran that 12.1/ 115mph the car through the belt ( I think when I hit 3rd) when it though the belt it picked up some water and sprayedthe windshield through the cowl. I did kinda seem to fall on its face as I went through the traps. Maybe it pulled some water into the carb ?? Also, I need some practice on my power shifting. I tried to power shift the car my first 2 passes but I missed second both times. So on the pass I ran 12.1 I was letting off to shift the car.

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  #17 (permalink)  
Old 09-17-2013, 10:25 AM
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Originally Posted by F-BIRD'88 View Post
This is a cool lil Celica though.
Tanks F bird. Thank you for your help as well.
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  #18 (permalink)  
Old 09-17-2013, 10:44 AM
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Quote:
Originally Posted by F-BIRD'88 View Post
Something is killing the top end. Based on the 96 mph in the 1/8th the 1/4 mile MPH should be 120+MPH.
You are loosing 5 MPH and something is killing the top end power at the top of the track.
(fuel flow, lean jetting, High head wind, valve float, (valve springs wrong) excessive rpm.
Auto transmission or torque converter fried.. Clutch fried (manual trans)

Or you took your foot out of it too soon.

Just doing the rough math on a 115MPH and 2880 car weight the engine power calc did seem lame.

This light weight car should be running 120-121 MPH.
is this a auto trans or manual trans car?
rear suspension? Trap RPM? gear ratio? Did you let off the gas early?
Front end way too high thru the traps, trapping air under car, effecting traction, handing and top speed.
And scaring the S**T out of ya. Did you let off?
Remember the smallish carb, he's running out of breath up on the top end. Long tube headers will probably make this worse as they'll pull harder against a carb that's not large enough. I think a change to a 750 Holley and some long 1-3/4 inch tubes will help everything except hooking-up coming out of the hole. The carb and header change needs to happen together as it's also gonna be a tuning problem.

I agree with Cobalt that for the street the 1-5/8ths tube is probably a little better, but this setup is something of a tweener, lot of cam for the street but short for the track, wheezy E streets of which I ain't too sure Edlebrock gave him good advice on running big springs, small street friendly carb, and shorty headers. He's got to decide which he'd rather live with; street or strip.

Bogie
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  #19 (permalink)  
Old 09-18-2013, 07:48 AM
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what RPM are you shifting gears? are you over revving the engine?
lots of changes this winter,,,
make sure fuel delivery system is up to speed.
If you plan to get this car into the 10s,,,please do not even consider 1 5/8 tubes! Im thinking 1 3/4 tubes stepped to 1 7/8 for after the engine is figured out. carb maybe consider upgrading to 850?( I use a 950)
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  #20 (permalink)  
Old 09-18-2013, 07:59 AM
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Primary diameter is just one part of the whole picture that needs "fixing" if 10s are in the plans.
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  #21 (permalink)  
Old 09-18-2013, 10:07 AM
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Originally Posted by vinniekq2 View Post
what RPM are you shifting gears? are you over revving the engine?
lots of changes this winter,,,
make sure fuel delivery system is up to speed.
If you plan to get this car into the 10s,,,please do not even consider 1 5/8 tubes! Im thinking 1 3/4 tubes stepped to 1 7/8 for after the engine is figured out. carb maybe consider upgrading to 850?( I use a 950)
Shifting the car at 6400ish. It deffiantly feels like it pulls hard all the way through. Yes lots of changes to make. I know it is nice make 1 change at a time so you can tell the affect it had but i just have to much going against me right know. I'm running a mechanical edelbrock RPM 140 GPH know. I've decided to go with 1 3/4 for sure. As far as the carb goes this has been a tuff section to make. All you guys on the forum day 750 minimum. I spoke to Holley tech and they said 750 is to big and that a 650 will be more than enough. I don't know if this is a case of real world and what and tech guy is reading out of a book ?? I truly respect your guys opinion and was going to go with a 750 for sure...... But know an 850????...... Vin, your killin me lol!!!
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  #22 (permalink)  
Old 09-18-2013, 08:35 PM
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Think about this,local fella here Brandon,Gen 1 Camaro/355 auto,small roller,dart heads,,,,,,,,ran a best of 10.9 with a 650 double pumper
carb body,ported
air horn,removed
baseplate 850
actual flow through highly modified carb
,,,over 1000 cfm
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  #23 (permalink)  
Old 09-18-2013, 09:53 PM
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Quote:
Originally Posted by prostcelica View Post
Shifting the car at 6400ish. It deffiantly feels like it pulls hard all the way through. Yes lots of changes to make. I know it is nice make 1 change at a time so you can tell the affect it had but i just have to much going against me right know. I'm running a mechanical edelbrock RPM 140 GPH know. I've decided to go with 1 3/4 for sure. As far as the carb goes this has been a tuff section to make. All you guys on the forum day 750 minimum. I spoke to Holley tech and they said 750 is to big and that a 650 will be more than enough. I don't know if this is a case of real world and what and tech guy is reading out of a book ?? I truly respect your guys opinion and was going to go with a 750 for sure...... But know an 850????...... Vin, your killin me lol!!!
Carb size depends a lot on how you'll use it. Same for the intake. If this is a track only or mainly vehicle and you're not so concerned w/how it acts as a daily driver then using a carb big enough to max the output at the top of the powerband is the way to go. In that scenario an 850 on a single plane intake like a Vic Jr. is not too big if you go w/more flow and cam to get the 10 second time slip. Personally I'd rather see you using a good electric pump and a bypass regulator w/big lines.

One thing you have going for you is the weight of this rig. Once you get the ladder bars adjusted, the rear spring rate sorted and the rear shocks dialed in (hopefully they have compression/rebound adjustability and not just spring/ride height) and a set of front shocks that will allow the front end to rise at the hit but settle right back down (this can be helped w/a drag-type front spring), the 60' time will improve and it won't be ill handling at the big end. You're still gonna want as much tire as possible. Burnout and tire pressure are also important.

Chris Alston has some useful info. Some more reading here, by one of the original Ramcharger guys, Bill Shope.

Personally I'd rather see you using a good electric pump and a bypass regulator w/big lines.
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  #24 (permalink)  
Old 09-18-2013, 10:01 PM
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quote
"Personally I'd rather see you using a good electric pump and a bypass regulator w/big lines."
for road race I think a mechanical pump is safer.engine dies,so does fuel flow.I use a nascar mechanical pump and most important,a regulator.
big fuel lines is allway a good idea if you make power...
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  #25 (permalink)  
Old 09-18-2013, 10:17 PM
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Is this a road racer? In any event, many racers (and the OEM) use a pressure switch and/or a rollover protection switch to stop fuel flow in the event of an accident.
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  #26 (permalink)  
Old 09-18-2013, 10:33 PM
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pro has a nice/fast street car. I think the little monster has a lot of potential.
I have used electric and mechanical pumps.Big electric pumps(not in tank) can be quite loud.either way,the car needs volumes of fuel,and other things already mentioned
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  #27 (permalink)  
Old 09-19-2013, 12:08 AM
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Edelbrock claims the pump will support 650hp so I should be ok no ??

I have t agree Vin. I feel like there could be some more potential there for sure. I say this as I have done nothing to attempt to tune the Motor yet besides bump the timing up and down a degree or 2. I couldn't even tell you what size jets the carb has in.

Last edited by prostcelica; 09-19-2013 at 12:22 AM.
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  #28 (permalink)  
Old 09-19-2013, 12:21 AM
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everything in the car is working,just not that well.hook/launch is a big effort to get perfect.as horse power increases,the suspension needs to be retuned. When you get some more engine power,the suspension problems will get worse.
It will take a couple years of fun racing to get the car fast.By the time everything works perfectly,it will be time to freshen the engine and change something,,,
remember MPH = horse power
115 mph is a strong mid 11 second car or better.
when I changed my 750 double pumper for an 850 I picked up 3 MPH

fix your suspension first
get a race wheel alignment
dial in the shocks and traction bars
front sway bar is not always a good thing to have
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  #29 (permalink)  
Old 09-19-2013, 12:43 AM
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[QUOTE=vinniekq2;1771953]everything in the car is working,just not that well.hook/launch is a big effort to get perfect.as horse power increases,the suspension needs to be retuned. When you get some more engine power,the suspension problems will get worse.
It will take a couple years of fun racing to get the car fast.By the time everything works perfectly,it will be time to freshen the engine and change something,,,
remember MPH = horse power
115 mph is a strong mid 11 second car or better.
when I changed my 750 double pumper for an 850 I picked up 3 MPH

fix your suspension first
get a race wheel alignment
dial in the shocks and traction bars
front sway bar is not always a good thing to have

Yeah. That's the plan for the winter

Fix front geomitry
Softer rear spring
Long tube headers
Bigger carb
AFR gauge/O2 sensor
Maybe a V gate shifter

Then we will see were we are at. Hey vin. What makes a drag race alignment different than a regular alignment ?? Less toe in ??

Last edited by prostcelica; 09-19-2013 at 12:56 AM.
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  #30 (permalink)  
Old 09-19-2013, 08:03 AM
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most drag cars go through the traps with the front end higher(full power)than when cruising.
specs change when suspension moves. The alignment guy can optimise the toe in for your car by averaging specs at different heights. Some cars can go a 1/10 quicker with a race alignment but might not be easy on tires for normal driving
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