what size exhaust?
 

I have a RB disassembled road race header, pineapple racing sleeves, no cats, and single muffler. Is 2.5" exhaust the best or what size?

MODS
K+N air filter
new plugs
RB header - in the process
Pineapple racing sleeves - in the process
Hi-flow muffler

run the 2.5 inch

Perfect:peace:
2.5"

thanks, i have also lightened the car and hope to remove emissions pump and run ~ 14.7 in the 1/4

good luck

I have heard of Rob at Pineapple Racing, but what are the sleeves, and what do they do?

I ran a High 15.3XX

with the RB header, DLIDIFS, gutted cat, stock muffler, 83 12a transmission and 12a 3.909 LSD diff
the car weighs ~2650 bls (truck balance) with the driver


Note that I had favorable winds :D and im not sure if the 6 port actuators wer fuctional at the time.
I aint no draggin pro. it was my 1st official time at the strip and I only did 5 runs. Damn my R/T sucks :(


Let me know what you end up doing with that setup

You will get faster as you learn how to launch your car...what were your 60 ft.s like? That's where it's all won or lost...if you're doing low 15s now, you'll be in the 14s soon with no other change except seat time... :cool:

ok here's the full rundown on my best run

R/T .797 :(

60 ft 2.302

1/8 9.878

1/4 15.369

MPH 89.33

2.3 doesn't seem that great... I haven't dragged an rx-7 before, but my fiero (2600lb, 140HP, 170TQ, MR, Pile of shit) does 1.7-18 60' times... that's stock, on shit 235 series tires, btw

.797 is pretty bad for reaction, too
LAUNCH ON THE LAST YELLOW!
I used to launch around .685, then I learned that if I launched when I saw the last yellow, instead of waiting till the geen, it went to .535 the first time I did it, and .516 the second time!... HUGE difference!

The 60 ft.s have got to drop. You're losing almost .3 on reaction time, so you're almost in the 14s right there. It's actually leave as you see the last yellow going out. Don't wait for the green. You've got a 14 second roller, man! It's there, you just gotta get some seat time! ;)

man what the hell are you guys running? 13Bs???

GSL-SE
with the mods stated above.

MOntrealer - has dlidfis helped u at all, and is it worth the hassle ? also, how long and how much to do??

Man I think drag lights are dumb in design. If it weren't for them and the timer just simply starts once the car starts moving, it would make the reaction time redundant. Ofcourse this would make it hard to have 2 cars "drag" each other. :) ...which I don't care about I guess. Dragging only tells you how bad you are at launching. Here come flames for no reason. :D But seriously, why does it matter if you start at the same time as another car anyway?

Okay here is how these stupid lights work. The staging beams tell you where you are. The first one has nothing to do with with the timing of the run. The second beam does. The starting beam starts the clock. The finish beam stops the clock.

When you come up to the stage and the second light is litt, that means you are ready, duh? The tree is then started. 1..2..3..4.. green. When the green light comes on nothing happens, nothing. The clock is only started after your front tires break the starting beam. Your reaction time is the time from when the green light comes on to when your front tires cross the starting beam. And as we know from above that the finish beam stops the clock. So your reaction time has absolutly ZERO affect on your 60', 330', 1/8 ect ect ect.

The reaction time is to be used to determine who started moving first. You 60' time can be used to determine how well you are launching ,and how consistanly you are launching. All of the other numbers on that time slip do the same thing as your 60', allow you to judge you consistancy.

Ever hear of the phrase "he wins it on the hole shot". What that means is that the cars are running nearly idendical times ( a 4.990 to a 4.998) and the race was won by the guy with the faster reaction time, which could have been the guy with the 4.998 if his reaction time was atleast .009 sec faster than the other guy. Make sense?

Ryan

I love how these threads start at "what size exhaust should I run" and end up at "I ran a 13.5 on k-mart 165's in a snowstorm!!" :p: **Ducks and Runs**

Jeff

I still think dragging is dumb for so-called bragging rights. Who crosses the start and finsh first doesn't matter much too me as long as the 1/4mile time slip is based on a automatic start watch controlled by the motion of the car and stopped by the motion of the car as it crosses the 1/4mark. Who's car is faster will have a smaller number even if it doesn't cross the finsh line at the same time or after some other car is all that matters to me.

Really!! OK, let me get it back on track...the 2.5" exhaust is fine and dandy. But is it worth it, HP-wise, as opposed to a 2.25"? The reason I mention this is because the 2.5" system will be louder than the 2.25" system. Is the extra loudness worth the 0.4 sec difference in ET? If you've got a decent stereo, you'll have to have more power or more sound deadening to compensate for the extra loudness. If you went the dampening route, you just negated the extra HP of the 2.5" system. If you went to bigger amps and speakers, you've done the same thing but on a smaller scale. Time to change the jets to the 125 shot. :p: and to the other subject matter...Wacky, your world means that a computer starts both cars and runs them to the end of the track to see which is faster. But guess what. When you get in, the car may not ever be that fast again. The drivers' abilities are half the fun of drag/street racing... whomever crosses the line first, wins...all the info on a timeslip tells you why you either won or lost and where you need to improve... :cool:

they replace the crappy 6 port sleeve's in the 13b NA cars with higher flowing units.