I just took my 98 5.7L ECSB to the track for the first time. The only mods are a K&N and Exhaust{stock manifolds}. The best pass I got out of it was a 16.39@82mph with a 2.3x 60ft. I realize the 60 sucks but does the mph seem low to anyone else. It was about 80 degrees out the day I ran with a slight headwind. I know the LS1 based trucks are much quicker but I expected slightly better numbers. Oh well it''s just the tow vehicle anyway.

 

I think those times are fine. The MPH is right in there to. A sub 2 sec 60' in a truck is flat out moving. Your times are respectable. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

I have a buddy with a 98 ext Cab with the 5.7 and it has dual exhaust, some intake mods, pulleys, a chip of some sort and 3.73 posi, on a good weather day he runs 15.90s@84-85 and on typical Houston crap weather he runs 16.10s-.20@82-83 mph. Not sure about the 60's but I know they are in the 2.2s. I would guess your truck is right in line. All depends on the weather, track conditions and altitude of the track.

 

LS1 rules. take it from a guy that had a slow *** 94 ext. cab with that worthless 5.7!

 

Okay, thanks for the replys. I want to get rid of my dual 2.25 in/ dual 2.25 out 50 series flowmaster, and get a better and slightly louder exhaust. I was thinking of running dual 2.5" pipes with a magnaflow x pipe and two 40 series flowmasters with dumps. Hopefully that will allow the motor to rev more freely than it currently does.

 

You can make that 5.7 run alot better. I had a 98 extended cab 3/4 ton with a 5 speed that ran 15.7x's in warm weather. All I had was an air raid, pullies, HPP, 160 stat, headers and flowmaster exhaust. The exhaust was a 50 series 2 in 1 out just like you had. Those times were with no traction thru 1st gear and spinning a little in 2nd.

 

There is a 5.7 Powerdyne supercharger kit on Ebay right now.

 

Man, so my 99 Tahoe is going to be CRAWLING at the track.

I might go tomorrow...

99 Tahoe
2WD
3.08's, locker
All stock with new plugs
5000 lbs with me in it

I do have the police package.

Now I really want to run it.

Do the catbacks have different diameter pipes or is a muffler swap enuff? I think an airbox, catback should help a lot.

 

Yeah, That set up is probably low 17's with more weight and those gears. My truck has 3.73s with an auburn and it was lighting up the stock 235/15s up off the line every time. best 60 ft was 2.3. I miss my Z28, but at least it is almost done....been 4-5 months since I last drove it.

 

Well I have gone low 11's to low 17's in my various vehicles, and this Tahoe is not a 17.2 vehicle.

I would say low 16's.

I can dead hook it foot braking it up to 1500 rpms.

I think I will try tomorrow.

I'm guessing 16.3@87mph, but hey who knows LOL.

It's my tow vehicle too.

Maybe I should put a $1200 blower on it.