indirocz28

OK- i had some hangin low draggin *** glass packs on my car and decided they needed to go- so i had the muffler shop build me a custom y pipe that is dual until it goes to a 2into1 w/ 3" single outlet..

For some reason- my car feels slower now than it did before.. I woulda figured that getting rid of my Acetelyne torch bent pipes w/ glasspacks would have made the car be able to expel gasses faster..

What is going on here?? should i have the shop finish off the exhaust w/ the 3" pipe all the way back into the 80 Series flowmaster w/ dual outlet's? or should i do something else???
Thanks

D's89IROCZ

Lets see soem pics of it . Might be a bad job. Or it may be really opened up and you are noticeing a loss of lowend grunt because of it .

88GTAbandit

iTrader: (1)

wat size are the 2 pipes that are goin into the y-pipe? sounds like dual 3in-single 3in? a friend tha works a a muffler shop told me that by him doin 3in from headers to a y pipe would be too big and i would loose power...he recommended 2 2.5 in pipesinto the single 3inch pipe...so if u have 2 3inchers goin back into 3in single, that could be the problem..

dave

urbanhunter44

iTrader: (3)

More than likely the tuned length of the exhaust has changed, since you now have freer flowing exhaust. Your powerband moved up as a result and it "feels slower." It isn't.

If you run it back to flowmasters the tuned length will again change, you will lose some power, but the powerband will drop down again.

Check the backpressure FAQ in my sig for some more information on the subject.

indirocz28

Id take pictures but i dont have a jack- and the pipes coming off my collecters are 2 1/4 " - the guy said it was to tight to run 2 1/2. but those then go to a Y saddle w/ the 3" open end.. and maybe i did lose some low end torque.. also the car sounds meaner when i step on it .. it has that GRRRAAAWWLL GRRRAWWWLL sound.. when i rev it a little.. about 3500rpm's its just ear ringing..

Also- Thanks for the Back Pressure link- i'll be sure to read it..

Another thing is ( i know this has nothing to do w/ the exhaust section but ne ways) when i stomp on it and my tranny kicks down- say from 3rd to 2nd ( for rolling street racing) it revs to like 6000 before it shifts and if i shift it manually i have to shift at 4200 to get the trans to shift at 5200.. its like a 2 sec delay or something..700r4 w/ stock converter.
whats up w/ that? - it was like that before the rebuild too..

88GTAbandit

iTrader: (1)

my 700r4 does that too

urbanhunter44

iTrader: (3)

You mean like you floor it and it sort of kicks into neutral, hits 6k and then shifts?

If that's happening, then it's nothing but bad news

indirocz28

no-it revs and the car takes off, but it just never shifts until i slightly let my foot off the pedal. but it still has a delay if i shift it manualy even if my throttle is at say 90%.. and if i put it in like 3rd and stomp it- it kicks down to second then wont shift till i let my foot of to abou 90% throttle, shifts, and takes off into the next gear

I also have pic's of my Y- pipe..- i hope they work..

Dialed_In

iTrader: (3)

That ypipe actually looks really good. Where is the 02 sensor mounted?

indirocz28

the o2 sensor is mounted in the scavenging part of the hedder- above the collector bolt on part..- kinda like the stock exh. manifold location- only lower down b/c these are hedders.

indirocz28

i've adjusted my TV cable and it seems to have cleared up any of the shifting things except at high rpms when shifting from 3rd into OD- i just have to let off a bit..- then she goes..

Thanks!!!

89TransAmWS6

That is completely normal btw. Your 700R4 is designed to never shift into overdrive under full throttle, because you lose revs, which loses you power. Like you said if you let off the throttle, it will shift into OD.

Side note, someone I know had their chevelle I believe taken to a local dyno place, and they disconnected the OD on his 700R4 he had installed, which fubared the tranny fluid flow and caused the transmission to implode. Remember, you never need to disable the OD on these tranny's, it will NEVER upshift into OD under full throttle.

indirocz28

A guy told me last night that since i have an electronic lock up trans (700r4) that i could run a 3000rpm or so stall in my car and it would still get good gas mileage b/c it would still lock up when the computer tells it to... Is this true?

Thanks! Keep the info coming! you guys are helping me line out my car..