I have a 91 z-28 with a 350 and a stock auto trans. K&N and Flowmaster exhaust. I raced my car last fall in overdrive and ran 14.9 out of three tries, very long lines. Are you supposed to drag in drive with an automatic. How much do you think it will improve. I just dont want to go past red line and drop the rear end.

 

I have an 88 Iroc with 350 and 700R auto which is the same as yours. When you race take it manually to first and shift through each gear. Just watch your tach so you don't redline. Trust me it's easy. It will improve your time alot. You won't need to come out of drive after you have shifted into it. It should stretch the rest of the quarter. Good luck man!

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88 Iroc-Z
350 700R
Only mods include Flowtech headers and gutted air boxes.
Best Run: 14.63 @ 93 mph

 

I have an 88 Iroc with 350 and 700R auto which is the same as yours. When you race take it manually to first and shift through each gear. Just watch your tach so you don't redline. Trust me it's easy. It will improve your time alot. You won't need to come out of drive after you have shifted into it. It should stretch the rest of the quarter. Good luck man!

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88 Iroc-Z
350 700R
Only mods include Flowtech headers and gutted air boxes.
Best Run: 14.63 @ 93 mph

 

Leaving it in automatic shouldn't make any difference. If you get to the end of the track while still in 3rd gear then it will never go into OD even if it was selected. If you run out rpm in 3rd then you'll need OD to finish. It's just another gear that happens to be an OD.

Even a manual tranny only needs as many gears that it takes to get to the end of the track. A T56 tranny is NOT a 6 speed tranny. It's still just a 4 speed but has 2 overdrives. A true 6 speed will have closer gear ratios with high gear being 1:1.

Now if you wanted to cross the finish line at red line and OD with a 700R4, you could probably do it with something like 5:13 gears

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Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season

Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

it's not what gear you end up in, the difference is from shifting at a higher rpm it allows the car to fall back to a sweeter spot in the powerband after the shift. that helps it accelerate a lot.

lata
tim

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91 Camaro RS-LO3,Auto.
14.215@94.30 w/ 1.917 60'

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According to my 700R4 rebuild manual the line pressure is higher in D than in OD. This could mean the shifts are slightly harder. Whether this reflected in your ET I don't know.

The other reason for not running in OD in DYO racing is if you button off at the top end so as not to breakout and then have to gas it to the finish line your trans may shift into OD and then back to D when you floor it again.

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Cosmik Debris

 

your rearend will be fine. Mine is untouched and I beat on it hard while running almost 2 secs faster than you. the only time the rear is in danger is when the clutched is dumped from way high on a set of slicks. there are guys with autos running a lot faster than me on this rear without probs.

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91 RS W/carbed 350, Vortec heads, performer rpm, Comp cams Xtreme energy 224/230 duration and .477/.480 lift. BFG Drag radials. 3.42 posi,Corvette servoed 700r4, 3000 stallconverter. Edelbrock TES, 3inch cat, flowmaster with single 2.5 inch exit.
Best time yet to come
12's?? :crossthumbs:

This is a Pic of my car in race trim www.tbns.net/billyjay/camero.jpg

 

ok i have a B&M ratchet shifter so when i race i ratchet through the gears. i got a difference of .5 tenths off, when i used to leave it in OD. it would shift from 1st to 2nd then back down to first then up to 2nd again. and then shift early and then just almost hit 4th at the end.
It reall sucked. then some guy told me to manually shift my auto tranny and showed me what to do. and i went .5 faster. i was impressed so i went and got the B&M because i missed third one race and was knocked out of finals.
seriously ratchet the shifter throught the gears, it makes a difference.
oh and my car is now running a 14.03/97.8mph and i have never even unscrewed a valve cover. but i will be in the mid 13s hopefully this spring.
have fun man and dont worry about your rearend. it wont break unless as stephen said, manual trans with high RPM clutch drops. or drop it into first gear when doing 50mph. saw that happen on a 85T/A funniest thing ever. but that is a long story. so just go and have fun man.

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Jarrad
1990 IROC-Z L98 350 TPI
TH-700R4
G92- 7.5" 10 Bolt 3.23gears
Bright Red Hardtop/ Grey Custom Interior
5,507 IROC's; 2,415 5.7L IROC's Produced in 1990

DAILY DRIVER: 1991 S10 2.5L/5SPD WITH CAMARO RIMS

 

oh yeah 91gasz28 you are right about the right times for a 350tpi/700r4. i ran a 15.28 and then ratcheted and ran a 14.8, then started modifying and ran a 14.03 now. so keep it up. and work on your shifts.

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Jarrad
1990 IROC-Z L98 350 TPI
TH-700R4
G92- 7.5" 10 Bolt 3.23gears
Bright Red Hardtop/ Grey Custom Interior
5,507 IROC's; 2,415 5.7L IROC's Produced in 1990

DAILY DRIVER: 1991 S10 2.5L/5SPD WITH CAMARO RIMS

 

Is ratchet shifting mean manually shifting your auto trans?

 

stephen did not say that.......I did and I will take credit- thanx

 

Im not an expert but ill throw my 2 cents in,I know someone will correct me if im wrong. With an automatic stock shifter if you have it in the 1st postion you can move the shifter all the way to the overdrive position without hitting the shifter button, if you are manually shifting it is hard to go from first to second without slipping into drive. A ratchet shifter only allows you to move one gear at a time from first to overdrive so you dont miss your gear.

 

well put

 

ROFLMAO....missing a gear in a stock auomatic tranny.
Here's s secret guys, just in case you are too slow to figure this out. If you 'miss' second and put the lever in third, you didn't 'miss' anything. The tranny is only gonna shift into 2nd gear anyway, it won't shift to third until it makes it to the next shift point anyway. It doesn't shift to third just cuz thats where the lever is.
If you have a FULL manual valvebody, that's another story.
Some people are too damn funny...ed

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Ed Maher - Moderator @ The Carb Board
92 Z28 Convertible - Quasar blue / Tan top
LB9 4L60 GU2 G80 - stock, soon to be sleeper
-=ICON Motorsports=-

- Definitely prototypes, high powered mutants of some kind. Too weird to live, too cool to die

 

If your TV cable is adjusted correctly (and you may want to change it at the track vs daily), then it should shift just below your redline (if that is where you want it to shift) to right about 3000 rpms where your torque should be almost at its peak.

I just stick it in drive, rev up to just below my stall speed (about 2500rpms with a 2800 stall), and let off the break. It shifts at 5500 to about 2700 or so very nicely. I never really use my B&M ratchet...

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1984 z28 w/ a 357 cu in. monster engine which is looking like the posterchild for Edelbrock with the exception of the Holley 750vac... all the suspension stuff... 9-bolt posi disk is in...

-=ICON Motorsports=-

 

Ed Ive never met anyone who has a ratchet shifter in a car without a transpack or a kit that allows full manual shifts.

 

by missing a gear I mean going from 1st to D without getting the opportunity to hold the car in 2nd as long as I would like to in order to use all my power. I know you cant miss a gear in an auto......however, going from 2nd to Nuetral is close enough and causes the same problems.

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91 RS W/carbed 350, Vortec heads, performer rpm, Comp cams Xtreme energy 224/230 duration and .477/.480 lift. BFG Drag radials. 3.42 posi,Corvette servoed 700r4, 3000 stallconverter. Edelbrock TES, 3inch cat, flowmaster with single 2.5 inch exit.
Best time yet to come
12's?? :crossthumbs:

This is a Pic of my car in race trim www.tbns.net/billyjay/camero.jpg

Yes I know how to spell camaro- so dont ask. I didnt make the link

 

Okay if I shift it manually on my 700r4 trans, when im shifting through the gears should i left off the gas to shift or just keep the gas mashed to the ground while shifting? Dont wanna ruin my trans.

 

stay in the gas

 

Thanks for everyones help i'll have to try your suggestions and hopefully i will improve the 1/4 mile time.

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• Red '91 Z-28 350
• 700-R4 Trans
• T-tops
• no major power
  gaining mods, K&N
  Filter, Flowmaster
  exhaust -series 80-,
  exhaust cut-outs
• Best E.T. 15.0@93mph, Will improve that 1/4 mile time this spring.
• HardlinePerformance