PatProtegeGT1

Ca recommence Pat, ils nous croivent pas. Next time, il faut une camera digital.

azrakain

its not that we don't believe you!! Some of us do speak more that one language and you aren't hiding anything, so type in english please. Next time do take the digital camera, get a picture of the trap speed and time clock. Also take a video camera, post the run and also scan in your time slips. This will dispell any disbelief.....

5 Guardian

ill give my timeslips to my firend tomorow at our meeting and he will post it for you!

PatProtegeGT1

I will scan Mine today, and you will see.

Inimical_01ES

What's so wrong with their times??

I ran a 16.04 my first time on the strip with full interior (spare and all, even left all my books n **** in the back seat ) plus I was on my 19"s...

So, if they're running high 15s, I don't see the problem...

kc5zom

Running NOS is a little bit more extreme than disconnecting part of the exhaust and weight lowering.

5 Guardian

lol

kc5zom

Where are the time slips? My friend has one of those GTech (or whatevers) and we were talking about running a couple of quick quarter miles with it. Are those things even accurate?

nick

I always just let my foot slide right off the clutch is the best way and quickest way to get a good time in 1.4 mile.

Why take so much time to let it out?

I always thought Double clutching was pushing in the clutch twice in the same gear in an effort to get the rpms higher in that gear.

nick

I wonder about the 15.9 time. Mathmatically for every 100lbs of weight removed = 20 HP or 1/10 sec time gains in Quarter mile.

Seeing that you haven't removed 100 lbs. and I guess removeing the exhaust could have added 10-15. based on MP3 HP gains with free flow exhaust.


If I was you, put the exhaust back on. you going to burn out your exhaust valves. Pistons engines need backpressure to be running properly and be reliable.

anyway good time in the Quarter.

azrakain

if they need back pressure I guess all those race cars with straight or no exhaust must burn a lot of valves. Double clutching is bullshit for our applications. Transmissions have Syncros so you don't have to double cluth.

Traveler

Piston engines most certainly DO NOT need backpressure to run properly. Burning exhaust valves is usually caused by an exhaust leak at the cylinder head/exhaust manifold junction. The reason is that between exhaust pulses reversion sucks outside air in against the exhaust valve which is VERY hot. It's kind of like using an oxy/acetylene cutting torch. When you use the torch on steel, it heats up and glows red. This is your exhaust valve. Then you depress the oxygen feed and the torch gets hotter and the metal melts. This is your exhaust valve with an air leak next to the head. Any questions?

As long as the A/F ratio is correct, you could run shorty straight pipes 3 feet long off the head. The other thing that burns exhaust valves is a way too lean fuel mixture. If the valve gets too hot with a lean mixture under load, it breaks down. Also, if the valve clearance is too tight then the exhaust valve doesn't get enough contact with the valve seat and thus cannot cool itself. This is how valves are cooled. The time they spend closed on a much cooler part of the head. Valves seats tend to recede into the head as they wear which is why you see a lot of higher mileage engines burn exhaust valves. Because the maintenance wasn't kept up and the clearance tightened up to the point that the valve wasn't making good contact with the seat.

And by the way, it's 10 HP per 100 lbs. And removing the back half of the exhaust would probably only net 5 HP or so on a stock car. When we removed the muffler on mine on the dyno it was only worth a little over 2. We'll disconnect it at the back of the #2 cat on Tuesday to see what gains we get without the resonator.

1fatEs

I dont know how true all of that is about everyones time but the weather makes a diff..also just to let everyone know my cars best time on may 12 @ woodburn was


R/T 1.104
60' 2.406
330 6.769
1/8 10.341
mph 69.74
1000 13.388
1/4 15.968
mph 86.65

weather was about 70-80 (warm day)
and that was with a bad r/t and yes that was with stock tires...I let some air out ( down to about 27psi ) and also did a big burnout in the water box to warm up my tires....(and yes that does make a diff)..........just my .02 cents

5 Guardian

do I understand that you did this with a 55shot of the dry zex setup??? and thoses mod's

1fatEs

yep...that was with a 55 shot,filter,muffler,and new spark plugs but you will always get a different time if you are in different elevations so that is why i can say that most people will not or may not get the same times in different places so maybe you did run that....i just cant say that its not true......but I ran a 15.9 here in woodburn oregon