asd_srt

I feel like my trap speed is way off of what it should be. My car is a 08 a6 with TF255 heads, cmc-20 cam, yank 3200, kooks long tubes, vararam intake. I borrowed some 275/40r17s MT RT STREET. The owner told me it made 450whp at 21 century. I made 11 passes 8 out of the 11 were 11s (11.9-11.7) all at 118-119mph (which seems incredibly slow for 450whp in a auto). Weather was high 80s low 90s with a real feel in the upper 90s.
Not sure what the DA was.

I was looking at the 1/4 list on here and several bolt on ls3s are in the 120s. The ls3 internal modification list the slowest car on there is 11.9@121 and the slowest head cam ls3 was a 10.68@126.

I'm going to get the car retuned asap. I feel a head cam car shouldn't be trapping 119.

sevinn

I'd imagine it was knocking in the heat. If you have any way to pull data from the car (torque logs/hptuners/etc.) we could look at the data and see what's up. I see from you're profile that you're located in Fort Polk..if ever end up near Baton Rouge I may be able to help you out.

asd_srt

I don't have hp tuners yet. How sensitive are these cars to heat and knock? I use to have a big turbo srt4 and it would trap 120 all boost with 93 octane and 124 with a 30 shot in the summer here and it never knocked on those passes.

sevinn

Depending on what the tuner did, it could be very sensitive.

As your intake air temps climb, the car can pull lots of timing and in the heat I'd bet it was either pulling timing from the IAT or knocking.

Check out what the stock IAT spark table looks like. The columns represent air temp readings and the nubmers indicate degrees of timing pulled.

asd_srt

I didn't even think about them making it pull timing different. I'm sure the timing vs iat are really conservative. When I bought the car I was told it's his daily so it was a extremely conservative tune. I just don't see the point of heads with a cam to make not that much power. But I'll definitely get this thing retuned. Then take it back in a cooler day. Its not my daily so the tune can be a little more powerful. I just really don't want a head cam car running bolt on mph.

Stay dry down there!

jleews6

Did you buy the silver 4lt car from Texas?

asd_srt

Yep. I've been watching it since it went up for sale.

jleews6

Good for you. Its nice car and I made an offer on it myself. Tons of good parts on it and there is no reason why it shouldnt be very fast. I would say traps in the high 120s should be easy once you get it sorted. A couple things I would look at are
Valve springs,the tune and the cats.

Congrats its a beautiful car.

asd_srt

Thanks! I made a offer on it back in June when I got back from Afghanistan. I ended up going to buy a c5z but the owner wanted to play games then I saw the c6 dropped the price to 25,500 so I went and got it that weekend. I'm from sc so I won't needs cats (no emissions or inspection) and since he said it was tuned really conservative that was in my mind to get retuned also.

I just need to get my tires mounted and go learn the sweet launch spot for this car.

C6David

What intake is on it? High IAT's will kill the trap speed. But so will hot air in general. With my drag pack on in good air my bolt on ls3 usually runs 10.7-10.8@123-125. In the summer heat it slows down to 11.2-11.3@120-122.

A log on the car will tell you a lot. When my car was cammed making 452/411 through a 4k stall it would do 10.7@126. It could've gone faster but a piston let go. When it had a 3600 converter in it and hotter weather it did a best of 11.3@122.

HOXXOH

With a 3200 stall, my best launches were from 1200 rpm. I currently have a 4000 and like C6David, in good air (1000'DA is good for Phoenix) I run 10.9's at 124-126.
Last month I was in Indianapolis and ran a TnT on well worn street tires at 32psi, so soft-pedaling to some 1.8 & 1.9 60's gave me a best 11.72 ET. But even though the DA was around 2500 and the ambient temps were in the 90's, I still managed 120+ mph on 4 of 5 passes with heavy KR in 3rd gear.

If your 60' times are below 1.7x, you probably are getting a lot of timing pulled from high IAT and/or KR. If the conservative tune primarily reduced timing, the IAT just made it even worse.

Get a retune, but wait for a day that's cooler than 75* and make sure you don't have a bunch of leaves and crap in the air filter.

pocketrocket

Just an idea. Go to Drag Times and the DA Density Altitude Calculator . Plug in your data from your time slips and look at the results.You won't be disappointed!

asd_srt

The car has a vararam with a cut shroud on it.

You juse hold the rpms there then go wot? I tried to flash it from idle and it spun all of first, and holding it up to like 2000-2200 It would cut a high 1.7 low 1.8 60'. (This is my first auto car) I use to cut 1.7s all day with my 5 speed fwd turbo car.

I did the day calculator it said with a good day it would be more around 11.2-11.3 @122-123mph

pocketrocket

Seems like a nice time, adjusted for the weather.With some 50 degree weather this fall, you just might look at your time slip and have a big smile!

HOXXOH

When I had both the 3200 and 3600 Yank, a footbrake to 1200 RPM and then launch at WOT worked best for me. Now that I'm using a 4000 stall, I'm braking to 2000. If I try an idle flash it spins more often than not and 60' times aren't any better.

I can see part of the problem is the heat affecting the timing and the DA affecting your power, but after you did the Drag Times calculation, I'm pretty sure your tune is way conservative. When my bolton with a soft launch runs the same times as your H&C car in the same DA, you know something is amiss. The 450 HP claim kinda confirms that too, as I'd expect to see it somewhere in the 475-500 range.

asd_srt

Yeah the owner i bought it from who had all the work done said it was a extremely conservative tune which the trap speeds proved true. I was just really disappointed in the trap speed since one of my friends went 117 bone stock with a tune and drag radials. I got some brand new drag radials but its just been raining almost everyday here for the past 2 weeks so I haven't had a chance to go to the track and see how it does with better tires. Hopefully this month I'll get a new tune on the car and there's some good weather (at least not raining) so I can go back to the track.

asd_srt

I had the tune adjusted once I installed a wideband. The air fuels were at 10.8:1 wot with 22* of timing max. Now the air fuels are around 12.2:1 with 26* of timing up top. I went back to the track and ran a 11.44@123 with a 1.74 60' and da around 1000 to 1150. I still feel like something is off. After looKing at the track times on here I have the slowest h&c ls3 on here. The cam is 223/235 duration @ .050 .610/.620 with 1.7 ratio rocker arms 115.0 CL.

sevinn

I do feel like your mph is still a little low.

I went this past weekend, and on a crap run with a 1.9s 60' I got 11.4@127 in 1100~ DA.

I have a 223/231 .625/.623 111+0 cam with .030 milled heads though...but I don't think they are worth 4mph on you.

Do you have any way to make scans during your runs?

asd_srt

I don't yet. I'm putting money to the side for hptuners. You said you're down in baton Rouge I may need to take a trip down there.

sevinn

If you want to make a trip for a Sunday TnT at state capitol I'd be down to go to make logs.