Best Mods - HP to $$$ Ratio
#2
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Best Mods - HP to $$$ Ratio
Your prolly going to get yelled at for not using the search feature..
I can never find what I need when I need it..
I can never find what I need when I need it..
#4
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Car: 92 firebird
Engine: 305 tpi "stock"
Transmission: slipping
Axle/Gears: 3.42 posi disk brakes!
Re: Best Mods - HP to $$$ Ratio
i see u have a tbi do u also have a tpi but either way full exhaust is your best start.
tune ups go a far way to
tune ups go a far way to
#5
Re: Best Mods - HP to $$$ Ratio
yeah swapping to a L98 this winter have the motor almost built and ready to go. pretty much redoing the whole car. swapping the rear to 3.73 posi, rebuilding the trans, already redid the whole steering and suspension system. trying to get the car to run under 13.5 on the stock heads but with full intake mods - big mouth base, slp runners, ported plenum, air foil. then plan on doing 3" exhaust with shorty headers...
#6
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Car: 92 firebird
Engine: 305 tpi "stock"
Transmission: slipping
Axle/Gears: 3.42 posi disk brakes!
Re: Best Mods - HP to $$$ Ratio
what about a camshaft?? didnt see it would help with a good port job as well from ure local shop or ure self
or take em to a shop and get them to do it
theres a bunch of cams for sale on the classifieds
also if u havent already get a good feul pump if ure throwing this in ure tbi 91 bird
but u got a good start i believe u should see around high thirteens
or take em to a shop and get them to do it
theres a bunch of cams for sale on the classifieds
also if u havent already get a good feul pump if ure throwing this in ure tbi 91 bird
but u got a good start i believe u should see around high thirteens
#7
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Car: 1986 Pontiac Firebird
Engine: 97 LT1 W/ Alot of goodies.
Transmission: 4L60E W/ Yank SS3600
Axle/Gears: 3.27 9 Bolt BW
Re: Best Mods - HP to $$$ Ratio
Heads, Top Swap, Exhaust, Tune.
Pretty much switching away from the stock stuff GM put on it.
Pretty much switching away from the stock stuff GM put on it.
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#10
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Car: 92 firebird
Engine: 305 tpi "stock"
Transmission: slipping
Axle/Gears: 3.42 posi disk brakes!
Re: Best Mods - HP to $$$ Ratio
the stock heads flow well ported n polished is all over tgo so depends on the price of the machine shop
i got exhaust ported n polished all the way and intake gasket matched with some polishing around intake valves
and intake fully ported n polished looks amazing and some plenum polished up with sand blasted for 240 i thought as a good deal
same size valves though. . . . seeing wat these heads would do he quotes 25hp
any who stock heads do good also weight reduction aluminum drive shaft throw out ac and smog back seats aluminum pulleys waterpump etc
will do good for ya as well
i got exhaust ported n polished all the way and intake gasket matched with some polishing around intake valves
and intake fully ported n polished looks amazing and some plenum polished up with sand blasted for 240 i thought as a good deal
same size valves though. . . . seeing wat these heads would do he quotes 25hp
any who stock heads do good also weight reduction aluminum drive shaft throw out ac and smog back seats aluminum pulleys waterpump etc
will do good for ya as well
#11
Re: Best Mods - HP to $$$ Ratio
what about a camshaft?? didnt see it would help with a good port job as well from ure local shop or ure self
or take em to a shop and get them to do it
theres a bunch of cams for sale on the classifieds
also if u havent already get a good feul pump if ure throwing this in ure tbi 91 bird
but u got a good start i believe u should see around high thirteens
or take em to a shop and get them to do it
theres a bunch of cams for sale on the classifieds
also if u havent already get a good feul pump if ure throwing this in ure tbi 91 bird
but u got a good start i believe u should see around high thirteens
oh yeah i got a crane 2032 cam too
#13
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Car: 91 Z28 / 04 GTO
Engine: GMPP 350 TPI / LS1
Transmission: WC T5 / T56
Axle/Gears: 3.23 / 3.46
#15
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Re: Best Mods - HP to $$$ Ratio
I just put 3.70s in mine, and if I didnt have my .50 overdrive gear, and was stuck with 5 speed's fifth gear, which is pretty close (around .70) to a 700r4 ovedrive, I'd be going nuts on the highway. I also blow through first gear pretty quick, and the T56's have a tall 2.66 first gear.
#16
Re: Best Mods - HP to $$$ Ratio
I just put 3.70s in mine, and if I didnt have my .50 overdrive gear, and was stuck with 5 speed's fifth gear, which is pretty close (around .70) to a 700r4 ovedrive, I'd be going nuts on the highway. I also blow through first gear pretty quick, and the T56's have a tall 2.66 first gear.
what do you rev at on the highway? i was told on the 700r4 in overdrive when the converter locks up i should rev at about 2500 at 65mph
#17
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Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: Best Mods - HP to $$$ Ratio
you will have no 1st gear if you put in 373's. Gear ratio for 1st gear in a 700 r4 is already a 3.06! way taller than a t5's 2.66. You will be quicker with 342's.
#19
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Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: Best Mods - HP to $$$ Ratio
Change to a th350 3 speed and go carb or holley stealth ram and then u can use 373's.
#21
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Re: Best Mods - HP to $$$ Ratio
3.73 with my NWC T5 are a little short I might go with a 3.23 later on but I have no issued on the expressway.
Here are my ratios
1 2 3 4 5
2.95 1.94 1.34 1.00 .73
If I had a T56 I would def keep them but I really love having awesome acceleration in each gear.
Here are my ratios
1 2 3 4 5
2.95 1.94 1.34 1.00 .73
If I had a T56 I would def keep them but I really love having awesome acceleration in each gear.
#23
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Re: Best Mods - HP to $$$ Ratio
My experience is a cam is one of the best mods for the cash.
#24
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Car: 95 9C1,99 Sierra,90Sierra,00 sierra
Engine: TBI350,LM7,LT1,Vortec 350
Transmission: 700r4,4L60e,4L60e,4L80e
Axle/Gears: 10 bolt,14bolt,3:42,3:73,3:08,3:73.
Re: Best Mods - HP to $$$ Ratio
Long tube Headers.
#27
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Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: Best Mods - HP to $$$ Ratio
you probably wont be able to tell its there unless you powerbrake it. You having a shop do your rear end?
#30
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Car: 91 Z28 / 04 GTO
Engine: GMPP 350 TPI / LS1
Transmission: WC T5 / T56
Axle/Gears: 3.23 / 3.46
Re: Best Mods - HP to $$$ Ratio
I just rebuilt my dif or I would swap to a 3.42 set up.
#31
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Car: 91 formula
Engine: 350 tuned port. bolt ons
Transmission: 700r4
Axle/Gears: 3.73
Re: Best Mods - HP to $$$ Ratio
i did go with a 373 gear. I have been driving it on the streets every day and on the highway with no problems. What problems do people say you will have with the 373? My mpg are very good two 15 City 25 highway.
#32
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Re: Best Mods - HP to $$$ Ratio
Something like this would help. Not a bad asking price, either!
http://swmi.craigslist.org/pts/2726097900.html
http://swmi.craigslist.org/pts/2726097900.html
#33
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Car: 2002 ws6, 2011 sierra 6.2L 6 speed
Engine: ls1
Transmission: M6
Axle/Gears: 3:42's
#34
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Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: Best Mods - HP to $$$ Ratio
Now you have no 1st gear at all. Going 60 down the highway and it feels like you need to shift. It is like being stuck in third with 2.73's and going 60. Also, will go through the usable powerband too quickly at wide open throttle.
#35
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Car: 91 Z28 / 04 GTO
Engine: GMPP 350 TPI / LS1
Transmission: WC T5 / T56
Axle/Gears: 3.23 / 3.46
Re: Best Mods - HP to $$$ Ratio
This is more so a problem with having an auto. I have a 2.95 and it's pretty decent. Someone with 3.42's should post their opinion.
#36
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Re: Best Mods - HP to $$$ Ratio
yeah swapping to a L98 this winter have the motor almost built and ready to go. pretty much redoing the whole car. swapping the rear to 3.73 posi, rebuilding the trans, already redid the whole steering and suspension system. trying to get the car to run under 13.5 on the stock heads but with full intake mods - big mouth base, slp runners, ported plenum, air foil. then plan on doing 3" exhaust with shorty headers...
Then do headers/exhaust, set base timing up from 6 to 8 or 10 deg...i liked 8. really could burn a custom chip to get the best timing curve for WOT performance. Bring timing in faster by 2800-3000 rpms.
Free mods like gut the TPI air box if you use the camaro style intake. Or build a CAI for a firebird since it looks like you have a bird.
My stock TPI car with the above mods went 13.63 at 97mph in good air. Just exhaust/3.42 gears/advanced base timing, and 2800 stall with slicks.
If you go aftermarket TPI, your goal will be even easier to meet as long as the car aint over 3500 lbs with you in it My buddy's 88 formula went 13.5's on street tires with 3.70 gears, TPIS base, SLP runners slightly siamesed, but corvette L98 heads, but they dont gain much if anything over iron L98's. Maybe a few ponies. He is on street tires with stock converter too! 1.93 60 foots. Thats not very good and still runs great ET's. Almost shifted to 4th on the 1/4 mile pass. Slicks and converter, he'd be 13.2's
If you have slightly siamesed runners to extend your powerband, 3.73's will be fine. Alittle too much for stock TPI, 3.42's would be better for that. First gear goes by fast but it gets you off the line HARD with TPI torque. TPI cars use the launch to run ET's, so more gear does help alittle. Daily driving is nicer with 3.42's and lower tho.
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