gymratt

iTrader: (3)

I have an AI ported heads/spinmonster cam/ported fast102 06 a6 with a 3000 circle d stall. Two years ago the car's best was a 11.989@117 bolt ons and stall on 305 35 18 nitto 555r at 17# pressure. The 60ft were 1.87. My car put down 372rwhp at that time. DA -693

Tonight with toyo tq drag radials in 315 35 18(much wider than the narrow running nittos) the car ran 11.590 at 117.27 with a 1.87 60 ft. Tonight's DA was 961.
My car now makes 456/421, 86rwhp more than the bolt on time above but the trap stayed the same. The brand new toyo tq drags are 26.6 tall where as the nitto were 26.4 tall. I included both slips for comparison.

Tonight I was running 20# in the rear and 44 up front. I was getting low & high tire pressure warnings and the rear seemed light and loose towards the end of the 1/4 on each run, kind of floaty. I only got one decent pass. I was short on time and cars kept breaking so it was 3 runs and done.

I don't really do a burnout just a quick spin to clean the tires. I am working on my burnout technique but it's weak since I use a hand control to drive(paraplegic). When launching I roll into the throttle with my twist style hand control.

Could the added tire width and slight height increase account for no trap increase after heads/cam? It shifted fine on the last two runs(roughly 6500rpm). Just seems weird that I would be trapping identical mph after heads/cam/ud pulley that I was just bolt ons. I thought I would be in the mid 120's. Thanks for any insight

HCI2000SS

iTrader: (2)

None of what you mentioned should matter enough to keep you trapping the same after 85 more hp like that. I'd go talk with your tuner first

1970camaroRS

iTrader: (8)

Interesting. Your 1/8th mph picked up like it should have, but somethings not right on the back-half. What RPM are in pushing through the traps? Fuel pump slowing losing pressure through the run? Valve float is a possibility too, but doubtful.

gymratt

iTrader: (3)

6k plus. I honestly didn't get the exact rpm as I was distracted by the floaty back end sensation. I wanted to log my runs with hp tuners but forgot my laptop. I'm going to re Dyno the car this week to see if there's any drop in hp. There's another guy on a different forum with an ls2 that also falls off after the 1/8.
Just weird that I'd pick up 4mph in the 1/8 but run the same 1/4 mph as pre heads cam even with an approx 1600 da difference

vetteboy2k

iTrader: (5)

I agree with Scott.
Also, You need to do a burnout. You shouldn't be breaking traction and floating. I'd be running a Hoosier anyway.
Be safe and post in c6 performance on the CF.

Kevin97ss

Where does the power peak on this so called "spinmonster"?

gymratt

iTrader: (3)

On my build peak of 456rwhp is at 5800 and pretty much stays there until 6600 where it's still 450rwhp. Peak tq is at 4800 and stays there until 5500where it very gradually declines it's still at 400rwtq at 5900rpm. I'm on a smart phone so I'm not sure if I listed the cam specs above. It's 230/234 612/598 114+2. I know there are bigger cams out there that make more hp but the daily drivability of the 230/234 is excellent.

FWIW"spinmonster" is a forum member on corvette forum and he spec'd out a cam with great dd characteristics that makes good hp. He's kind of the cf cam guru since he has installed a ton of various cams in ls2 and ls3's and compiled extensive data on the differences with cam change only.

I discussed the cam with Pat G and he concurred that it's a great choice for my goals. I just wanted a summer dd that was capable of low 11's in decent air with a good driver(not me since my 60's are terrible).
I posted this on ls1tech because I have always thought this forum had more hardcore racers at heart. I love cf but there are a lot of members that buy a vette and never mod or track their cars. If this thread is not appropriate on this forum mod you could please delete it. Thanks

gymratt

iTrader: (3)

I agree on the burnout. I actually wasn't breaking traction other than a little off the line. The rear was feeling light/floaty over 100mph that it wasn't exhibiting with the narrower nittos. I'd love to run the Hoosiers since they are way lighter and stickier but I wanted a street friendly drag radial that wouldn't fold over on itself going into a turn.
I posted here because I figured the forum had more hardcore track oriented members. We have a lot of no mod/no track members mixed in with the hardcore track guys. Here everyone mods and most track their cars as well.

Kevin97ss

Welp, a spin monster is what it will need to be to get the et/mph your looking for. You moved your average power much higher up in the rpm band which means much higher shift points and trap rpm. Think 7k+, also the converter is no longer participating in the "combination".

If the short block is willing and able, up the shift points, change the gear and converter. Oh, and run a little more tire pressure out back, 22-24 psi, a drag radial should not feel loose.

vetteboy2k

iTrader: (5)

Got ya. There's a few guys on there like Dennis who can and will help you eek out some more on the drag strip.
Typically when you post a 1/4 mile thread we will find it.
Experiment with different tire pressures and launch techniques if you are committed to keeping your exact setup. Do a full burnout. Your mph does seem low.

T6Rocket

DA cannot be helping. You mentioned -693 DA on your previous runs, and Summer is in full swing now. What were the conditions when you ran?

I agree on the shift points/gearing/higher stall helping. Cams make more power, but at a higher RPM. They take additional work to get that extra power translated to the ET.

Al

gymratt

iTrader: (3)

The da last weekend was 985ish. So it's approx 1600 or so difference from previous runs. I would've gone a bigger stall but was looking for a lower stall for boost.

slow trap

iTrader: (22)

something is out of whack past the 1/8 th. it picked up 24 mph before and only 21 after. even with the da difference it is faster in the 1/8 th so it should be even faster in the 1/4. don't know what is the ailment but your car will be 121-123 mph when its ironed out, imo.

gymratt

iTrader: (3)

Thanks for all the responses/insight guys!. I'm going to experiment more with the tire pressure, data log the passes next time with hpt and use a line lock to burn these tires up instead of the quick spin I was doing. Hopefully I'll get a lot more than 3 runs in the next time I go.

poltergeist 02

iTrader: (65)

I use to run Toyo TQ drag radials and I would have to do a John Force burnout to get them to hook. I switched to M/T and that problem is now gone. All it takes is a short burn out to heat them and they grab. Also, how much fuel do you run in your car while at the track? Last year I was paying close attention to my wide band on my runs and noticed it was going lean on the big end. I was running a 1/4 tank (which is what I read was ok to run) and the car would go lean, I upped it to 1/3 tank and the issue went away. Now this was in an F Body, I'm not sure if the vettes have similar fuel tank designs/issues...

gymratt

iTrader: (3)

Damn i was torn between the tq and the et street drag ll. I should've just bought the mt. That's what I get for reading mostly mustang cobra forums because it seemed they had the most feedback on the tq and it was overwhelmingly positive. It will give me more reason to go to the track and burn these up practicing my launches so I can do better than 1.8's.
I had a quarter tank but not sure if c6's are as sensitive to fuel levels but it's worth trying the 1/3 tanks JIC. Thanks

Pro Stock John

iTrader: (34)

gym, I'm pretty sure I've seen your car at the grove before, I'll introduce myself next time. I run a 2010 Camaro SS that is H/C/etc, it's cyber gray.

Your 60 is pretty soft. If you are not spinning you might want to consider running more converter. Your car have 2.56 gears out back?

I've been 1.58 a few times in my car last couple weeks on Nitto NTO5Rs.

gymratt

iTrader: (3)

I do remember seeing a gen5 gray ss. With all the various older cars at GLD we tend to notice the nice late model LS cars like c5,c6,c7 and gen 4 & 5 fbodies.

I wasn't spinning much at all on the passes but I was rolling into the throttle on each launch. Weird that I did spin pretty bad on my 3rd and last pass and still ran a 1.8X 60.
I definitely need a lot more practice on my launch and heat the tires instead of my quick stab/spin I'm doing to clean them. I do have the 2.56 gear but I have been thinking of going bigger on stall to 3500/3600ish. I would love a 1.5X 60 ft!
How big of a NTO5 are you running and what psi? Which converter are you running? thanks

scotty2000ss

iTrader: (2)

Sounds like you're not at peak hp when you go through the traps costing you hp and mph.

gymratt

iTrader: (3)

Do you think the bigger dr could have lowered my rpm's going through the end of the 1/4? Or should my shift points be higher than 6500 since it's cammed?The only change from my last 118 bolton trap mph was heads/cam/udp and new bigger wider heavier dr's and the +1600da change.
Damn I wish I had logged the runs to see exactly what rpm it was going through the traps and if kr or anything else was happening. I will definitely bring hpt next time to track. Now if I could get a weekend here soon where the DA wasn't 2200+