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In my quest for a 9 second pump gas street car I came OOOOOH SOOO close today. It was unseasonably warm, in the 60's today with a slight headwind which i'm told is worth a tenth on some of the faster cars so I'm confident I'll get 9's soon if i do go back out next week.
In the weeks after my last outing i broke something in my 10 bolt rear finally..... that thing took LOADS of abuse and finally a worm gear in the torsen diff chipped and started slipping on the other gears so I didnt trust it to hold up this weekend.
Last night I got a 2.73 posi (zexel torsen diff) rear from another 4th gen for 60 bucks... took just about all night to swap it in. Had to take out old, swap my axles to put in the new donor rear, then deal with rusty bolt holes/etc..took awhile but it was done and ready to go today.
Got a boost controller now set at 12 psi. First pass i blew the intercooler piping off again so I had to let off. Was on my way to a great pass too so i felt today was gonna be good.
First pass, 1.55 60 foot 4.24 330 foot and piping blew right before the 1/8...coasted to a 6.67 at 99 1/8 12.08 76mph 1/4
Left boost alone, launched again, 1.56 60 foot, 6.48 at 109.2 1/8 mile, 10.07 at 137.66 mph 1/4 mile!! Figured with 13 psi i'd get it done! here comes 9's
Spun a touch on launch, 1.58 60 foot, 6.518 at 110.9 1/8 mile, 10.06 at 139.15 mph 1/4!! AHHH frustrating... if only it would have launched like before.
No more playing around.... 14psi this time (actually only hit 13.8 on the logs).
Softer launch, but heres my best pass ever...
1.60 60 '
4.29 330'
6.4996 at 111.17 1/8 mile
8.409 1000'
10.0221 at 140.27 mph!!! If this aint close to 9's I dont know what is! If only it would have launched abit harder. 140mph traps and cant bust 9's
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
I watched your videos. Dude, you are harsh on those Mustangs, especially the way you blow by the white one you let leave first! As soon as you get your intercooler tubing to quit popping off, you'll go in the nines. You're so close. How are you getting past tech?
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by Orr89RocZ
First pass i blew the intercooler piping off again so I had to let off.
get some hairspray, and remove ur couplers one at a time, spray the pipe ends with the hairspray and reinstall coupler.
yeah i know it sounds dumb but it does actually work.
or build ur own boost braces
get some roundstock say 1/2 inch in diameter and drill and tap them in the center for 1/4 bolts
weld 2 behind each coupler on oposites sides of the pips, then get some thin alumin or steel sheetmetal and drill holes in them so u can place them from each round piece u welded onto the ppes over the couplers.
then install bolts and the pipes can no longer pull out of the couplers
i did this on every coupler on my car except the tb and it works great,
though once i reinforced all of those the tb coupler would pop off ll the time.
so i took the tb off and put weld spots on it in 4 places to make a lil bigger lip and havent had a problem since
dont mind the crappy drawing but it should look like this
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by project89
get some hairspray, and remove ur couplers one at a time, spray the pipe ends with the hairspray and reinstall coupler.
yeah i know it sounds dumb but it does actually work.
or build ur own boost braces
get some roundstock say 1/2 inch in diameter and drill and tap them in the center for 1/4 bolts
weld 2 behind each coupler on oposites sides of the pips, then get some thin alumin or steel sheetmetal and drill holes in them so u can place them from each round piece u welded onto the ppes over the couplers.
then install bolts and the pipes can no longer pull out of the couplers
i did this on every coupler on my car except the tb and it works great,
though once i reinforced all of those the tb coupler would pop off ll the time.
so i took the tb off and put weld spots on it in 4 places to make a lil bigger lip and havent had a problem since
dont mind the crappy drawing but it should look like this
Thanks thats a nice idea, i will have to try something. I tightened everything down ALOT and it held up. I really think i need to weld a bead around the tube ends to have the couplers holding something. I'll figure it out.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
You can make a simple tubing retainer similar to what GM used on their 6.5L diesels. Technically it's like the above attachment picture. A couple of tabs on either side of the hose connection with a rod connecting them together. You may still blow a clamp off the hose and loose boost pressure but it would be impossible for the tubing to pull apart.
Cut a couple of 1/2" x 1/2" x 3/8" thick pieces of aluminum. Drill and tap a 3/8" hole through it and weld them on the tubes behind the rubber connector. Pick up a couple of 3/8" rod ends and some threaded rod and make a solid connector to hold the pipes together. The rod ends will be bolted to the 1/2" blocks. Using the rod ends will still allow components to flex with the rubber connector.
I doubt you would need to make a rod for both sides of the tubing but it wouldn't hurt.
__________________
87 IROC-Z
All engine, no power adders! Bests: 9.348@144.71
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Congrats on great passes, the head wind suked! I should have stayed for last pass, it seems it may have stopped for that one.
Here is a low quality vid of your car, Fiancee had a good rear closeup of your 10.07 but it got blurry for some reason, I will send that to you later.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
its about time you get some laundry at the end of your car with the speeds your going. Good pass, keep up the good work, and you will get you 9 second pass
__________________ 383 Forged Stroker. Splayed 2 bolt mains, TPIS Miniram, ZZ409, Probuilt 700r4, Dart 200cc 2.05/1.60 Alum Heads, 3500 Stall, 12 bolt 3.90, Dyno Dons Headers and Y, All new Spohn suspension and crossmember torque arm. relocated battery, 3 inch cutout, custom 4 inch custom airbox by 1bad91z , working on cervinis cowl hood! 11.72 at 115.90 with 1.53 60ft
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
It kinda boggles my mind why I'm not in the 9's with 140 traps even with my weak 60 foot. Its funny because it went 10.07 on 12 psi and 10.02 on 14 psi yet i had 3mph difference and only .04 difference in 60 foot.
The converter I think is flashing like 4000 rpm, foot brake to 2400-2500, some runs show alittle higher. When I launch its not on any boost, just atmosphere pressure at most so far. I try to hold throttle more and it creeps through brakes. You can see it in my vids i start creeping forward before launch
I do not have a trans brake, and probly never will. It is a full manual tho. I need to get this thing to build some boost and it reallly does need 3.23 gears to be perfect.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
I would consider a trans brake. Turbo cars work the best with 4000 stall converters to take advantage of launching with full boost. You'll never 60ft off the footbrake. You're leaving with 300Hp and a 9 inch converter. A $300 T/B valve body will have you on the bumper and printing mid 9 slips.
__________________ 1986 Camaro Sport Coupe - 383/T-350/3k stall/4.10's
10.8cr, AFR 195's, victor Jr, Pro Systems 850.
COMP XE-284-H (241/246 @ .050 W/ .537/.540 lift)
Hooker 2210's (1 3/4) W/ 2.5 exhaust and Flows Motor all forged and studded for Nitrous
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
I dont wanna be on the bumper haha but 9 second slips sound great to me.
I really think most of my problem is my brakes and i have the wrong spring in my BOV. I dont even really need a BOV but I like it just for safety and sound purposes. Its got a spring for 10-13 inch Hg vacuum and I need the 14-17 in Hg spring since I develop alot of vacuum in this motor. I'm gonna shim it up and experiement with it this week before heading to the track again. I think its staying open when i foot brake and its not allowing the air to build up pressure
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by Orr89RocZ
Running big discs out back, 12" ls1's. Will not swap to drums, why do that? They are ugly too, my C6 wheels dont need drums behind them....
Unfortunately, this is the price that your going to have to pay if your electing to footbrake it. Drums hold much better off the line, and they will allow you to up the psi for your launch w/out the wheels creeping up on the laser. If you don't swap to drums, while refusing to run a transbrake, you'll never realize the cars full potential. Ask scojack the next time you see him to swap to disc brakes on his turbo regal and he'll look at you like you have three heads. It isn't that bad, you can always go with aluminum drums....
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
i'm just gonna get my C5 front brakes on eventually and it should hold just fine with good pads. Stock 10.5 vs 13 inch brakes,i should see the difference.
I wont have it done by next track meet sadly but i got one more thing to try to see if i cant get boost on the line. One of my passes it started to make 1 psi just before i launched and went to full boost instantly and spun... So maybe a boosted launch wont work anyway with these tires
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by Orr89RocZ
i'm just gonna get my C5 front brakes on eventually and it should hold just fine with good pads. Stock 10.5 vs 13 inch brakes,i should see the difference.
I wont have it done by next track meet sadly but i got one more thing to try to see if i cant get boost on the line. One of my passes it started to make 1 psi just before i launched and went to full boost instantly and spun... So maybe a boosted launch wont work anyway with these tires
why weigh the car down with heavy brakes? just put a transbrake on the car and pick up 2 tenths in the 60'.
fighting the car with huge brakes trying to get it to spool up just doesnt make sense to me when a tbrake is cheaper and a much better solution all around.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by Street Lethal
.... lol, not getting excited over the sixty foot, but its definitely doable w/the footbrake.
no doubt.... i had a 1.32 60' off the footbrake, but its a nitrous car. i left just a hair over idle. havent done any better than that with the t-brake. (yet)
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
why weigh the car down with heavy brakes? just put a transbrake on the car and pick up 2 tenths in the 60'.
fighting the car with huge brakes trying to get it to spool up just doesnt make sense to me when a tbrake is cheaper and a much better solution all around.
This car is also a street car, doing the pro touring style kinda.. 18/19" rims and big brakes are a must, i like to go around some corners and stop good just as much as drag racing. Plus i already have the kit, need pads and rotors and some bushings while i'm at it to replace stock steering stuff.
Plus stopping from 140mph yesterday kinda scared me with these stock brakes...hello last exit. C5's arent great but MUCH better than stock
I may do the transbrake some day but now I'd rather have the luxary of just putting the car in reverse and not holding buttons to back up Much easier to drive
My buddy's turbo LS1 can brake boost to 4-5 lbs and he cuts 1.5 60's and runs mid 10's at 130. I got much more power than him so i should beable to do the same. He runs a big single and i have a set of small twins on a larger motor, they should spool up
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
how much does your car weigh? my car stopped awesome with stock brakes, but its only around 3100# with me in it. i could nail first turnoff from 13x mph if i wanted to. it now has strange drag brakes all around and still has the stock power assist. works real nice.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
justin, not all transbrakes require you to hold the button to reverse. my dad's car isn't like that, rich's (carfixer) car isn't like that either. rich has a th350 and my dad's is a powerglide. so your excuse for not having a transbrake doesn't hold water. you need to get one. the only good excuse you have right now to not have one is your garbage 10bolt.
also, i have the ls1 front brakes on my car. when you're running the kind of power you are, you'll push right through them. my car with the baby cammed ls1 would push through them if i hit them too hard on the converter, and i was only running 111mph, so i'm dealing with a BUNCH less HP than you are.
do a little more research on the transbrake deal, i think you'll find you can have your cake and eat it too
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by Orr89RocZ
This car is also a street car, doing the pro touring style kinda.. 18/19" rims and big brakes are a must, i like to go around some corners and stop good just as much as drag racing. Plus i already have the kit, need pads and rotors and some bushings while i'm at it to replace stock steering stuff.
Plus stopping from 140mph yesterday kinda scared me with these stock brakes...hello last exit. C5's arent great but MUCH better than stock
I may do the transbrake some day but now I'd rather have the luxary of just putting the car in reverse and not holding buttons to back up Much easier to drive
My buddy's turbo LS1 can brake boost to 4-5 lbs and he cuts 1.5 60's and runs mid 10's at 130. I got much more power than him so i should beable to do the same. He runs a big single and i have a set of small twins on a larger motor, they should spool up
Whatever you decide, the car is a beast either way - its actually cool to see the car leave easy then start breaking loose 60ft out.. It would be siiick with a brake though, serious TQ off the line!! Probably too much though.. Would an adjustable regulator help to allow more power to rears? Just have to be careful on big end..
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
the turbo 350 i had you didn't need to engage the brake to go in reverse. the glide i have in the car now does. you can wire it into the reverse light switch on ur shifter and u wont have to hold the button down.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
I know I`m new on here and I don`t have a thousand posts but i have built 2 turbo cars both were small blocks and that car will never work right not leaving on boost it don`t make enough power on motor and most new style tb valve body`s back up without a button pressed that is a pain, Also i always run a msd 7531 box they are the **** slew rate and all that they also have a handy boost build function.So just my exp. not meaning to step on toes because I`m sure yall no stuff i do not. Bill
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by Camaro Bill
I know I`m new on here and I don`t have a thousand posts but i have built 2 turbo cars both were small blocks and that car will never work right not leaving on boost it don`t make enough power on motor and most new style tb valve body`s back up without a button pressed that is a pain, Also i always run a msd 7531 box they are the **** slew rate and all that they also have a handy boost build function.So just my exp. not meaning to step on toes because I`m sure yall no stuff i do not. Bill
Oh i know, when my pipe to the intercooler blew off twice, i had no boost and was running at just n/a... car was a TURD haha
The only advantage i got right now is that the small turbos spool so damn quick I can get good boost before the end of the 60, so i am starting to cut good times as i enter boost about 20-30 ft out i think. hard to say.
I guess i dont have an excuse not to have a trans brake other than the fact that I"m nervous to experience a 1.3x 60 foot or to see the sky through my windsheild... my 1.41 in the nitrous car almost made me black out haha...its too intense
Transbrake will come whenever i get my 9" or 12 bolt
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
i've had the fronts 12" off the ground, and honestly, you don't even notice it till it sets them back down. of course, people that have had them 3' off the ground probably have a different story to tell lol.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by mw66nova
i've had the fronts 12" off the ground, and honestly, you don't even notice it till it sets them back down. of course, people that have had them 3' off the ground probably have a different story to tell lol.
first time i sprayed the car i went from a 1.55 to a 1.34 60' in the same day. i remember it felt like i got hit by a grenade. lol
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
After a day at the track, do you guys feel beaten and tired like you just got out of the ring with Mike Tyson? haha I know I do.
Quote:
first time i sprayed the car i went from a 1.55 to a 1.34 60' in the same day. i remember it felt like i got hit by a grenade. lol
I did the same thing, scared the hell out of me. I was doing 1.55-1.60's all day spraying at the top of first gear. Decided to test the 10 bolt and sprayed off the line to a 1.41 60 foot. It was the most insane thing I ever been through.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Quote:
Originally Posted by DIGGLER
first time i sprayed the car i went from a 1.55 to a 1.34 60' in the same day. i remember it felt like i got hit by a grenade. lol
Good quote here.
Most Transbrakes today are Pro tree style brakes with two release passages in the reverse piston to speed up the release. The modification drops pressure when reverse is engaged. It requires the button being held to build the proper presure to move the car without buring up reverse clutches. It's a small price to pay for the advancements in 60ft for turbo cars. Some people choose to wire them to switches and reverse lights but a lot of people burn the solenoids up doing it as well.
You can also think about loosening the converter up a bit or going with a more agressive stator to spin the rpm's up at the line.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
I thouht of something on a mustang we were workin on a freinds car he didn`t want to fool a tb so we put dual calipers on the back he had big wheels like you do and they looked cool they also helt it on the line he could leave on about 9 or 10 lbs after that just an idea.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
trans brake and a stock rear end sounds like a bad combo to me... 2.73 gear pulling 1.6s without boost?
as for boost, what about putting a 2 step on it, set it to like 3k and it should build boost and not roll.
great runs, good luck getting in the 9s. we are all pulling for you. i still feel there's something in the tune that would help it spool at the line. but since i haven't done it myself, i'm not going to say i have a clue. just from reading stuff, it seems like its in there some where.
i've read that the st/ty guys do full throttle stomps from idle (i believe in netral)while logging, to tune that setion of the map, and that makes theirs spool much better. its just a quick stab, your not in it enough to free rev it very hi and hurt anything, but going back thru the logs, you can see the spots that need tuned.
ls1 brakes were a huge step up from my stock brakes, i'd think the c5's are better, but i wouldn't go for racing pads, like say hawks. you won't have much heat in them at the line, and the racing pads are meant to run in a higher temp range than stock. cheap stock pads might hold better at the line, now at the big end. that might be a different story lol
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Well i shimmed up my BOV spring and it seems to help now. It stays shut at lower vacuum so the turbos start spooling up once i get beyond that vacuum point. I took it out on a back road and was able to foot brake it to 3000 rpm without trying to hard... boost was at what looked like 1 psi or on the 0 so its almost ready to rock and roll at that point. Alittle more gas and it started to inch forward.
Its starting to build something much sooner than before tho. Should really help my launch I think. Leaned my tune out from about 11 to 1 to 11.4-11.5 to 1 at 14 psi. May go abit leaner still. Car feels good, just hope it runs good this weekend.
Re: Knocking on 9's door...Twin Turbo 401 w/ 12-14psi
Awesome Justin. It looks like you will see 9's. My motor is almost done at the machine shop. Amazing I started out before you with my Dart SHP block but you wound up way ahead of me.
14psi, street tune 
