04-29-2010, 11:22 PM | #1 |
5.slo stanger
Join Date: Jan 2007
Location: oxford alabama
Posts: 735
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possable gear change. opinions?
off the bottle my car is going through the traps at about 5400 rpm. the motor doesnt like going above 5500, this last time going to the track i turned a 12.7 at 111.9 and was turninbg about 6500. on the bottle off the juice its about perfect pulling almost redline as i go across the line. but on the bottle its running out. im not wanting to turn this factory bottom end that high and not going to do another intake right now for reasons left to be unsaid.
my setup is in my sig. bandit swears by the 4.10's in his car. but, imho im running out of gear on the bottle. i think a quick fix would be to put a set of 275 60 15 et streets on there. as apposed to my current 265 50's does anyone think i wil notice a big diffrent on the big end from the height diffrence of the two tires? or should i just break down and redo my gears and go with a 3.73? i was thinking 3.90 but i dont know if there will be much improvement going from 4.10's to 3.90's. any imput guys?
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04-30-2010, 04:41 AM | #2 |
Mind Blowing
Join Date: Jun 2006
Location: Dawsonville Ga
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U will see alot with a tire change. i think Matts car is heavier than yours
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Slow Joe Racing 2008 dodge ram 5.7 HEMI 1993 lx with a 289 and a 3 speed on the floor WTB 1955 t-bird project |
04-30-2010, 07:06 AM | #3 |
3v's are slow
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if you are not spinning above 5400 rpm, then 4:10's maybe a little steep. I loved the 4:10's in my car but I was spinning my 306 to about 6300 rpm on or off the bottle.
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2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy |
04-30-2010, 07:06 AM | #4 |
3v's are slow
Join Date: Dec 2004
Location: Here and There
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if you are not spinning above 5400 rpm, then 4:10's maybe a little steep. I loved the 4:10's in my car but I was spinning my 306 to about 6300 rpm on or off the bottle.
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2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy |
04-30-2010, 07:27 AM | #5 | |
Administrator
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Quote:
What heads and intake are you using again? Sounds like you aren't getting much out of that F-cam if it isn't making power above 5500 rpms.
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04-30-2010, 10:34 AM | #6 |
5.slo stanger
Join Date: Jan 2007
Location: oxford alabama
Posts: 735
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yea its just got home ported e7's and a performer 289 intake. neither of whichj like to flow above said rpm. it will turn up that high but it really falls on its head above that. and ive got my big motor on the stand getting built and not going to spend the money on another intake when i need one for my 351. my question is. with this motor im running out of gear. so theoretically im building alot more power with my big motor that translates into alot more speed. im thinkin im still going to be running out of gear with the big motor even if i can spin it a lil higher simply from the fact that im going to be gaining the speed quicker. basically same issue at a higher speed. i think i am going to try a tire change first ive never gon up a big diffrence in height as far as tires go. so i didnt know how much of a diffrence i will see
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no mustangs anymore but i do have a 1jz swapped 83 supra |
04-30-2010, 10:40 AM | #7 |
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I wouldn't mess with it a whole lot until you get the other motor finished. Chances are the new motors is going to rev higher even though you're also going to trap higher.
I'd do this: put the money into the new motor for now, see how it acts with the new motor, then decide what tire/gear change you may need to make.
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1998 Mustang GT Coupe - World's Slowest Racecar 2005 Toyota 4Runner SR5 V8 2013 Volkswagen Jetta Sportwagen TDI |
04-30-2010, 01:18 PM | #8 | |
3v's are slow
Join Date: Dec 2004
Location: Here and There
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Quote:
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2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy |
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04-30-2010, 05:16 PM | #9 |
Dayuuuuuuum!!!!!
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how big of a 351 are you building?
If its going to be a nitrous car either way I would toss a 3.55 in it and then you will be good for either motor. Just keep 26" tires on it and you're good to go
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05-01-2010, 05:05 PM | #10 |
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if you end up going with 3.73 let me know i got a set of new frpp gears setting here i might sale.
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