Wicked69

Will do. I can't friggin wait. Almost time to go race some big blocks!

Wicked69

I don't have to guestimate...lol I have had the car 4 corner scaled. It weighs 3870lbs with me in it and a full tank of fuel. This is 100 percent street car and daily driven. It has full interior, stock suspension, small tire, sound deadner, full exhaust, and a bad *** sound system complete with a subwoofer and amp in the trunk.

Sales1@Texas-speed

Glad to see some nice progress being made with the car. I remember when it was a big block nitrous car with light silver paint. Car has definitely changed a lot!

Wicked69

Yeah this ride has come a long ways. All of the engines have been fun but this has been by far the cheapest route and the most adrenaline rush once the turbos kick in.

Before I do anymore tuning I am going to drive it to St. Louis on Wednesday to run the 1/4 mile before I blow it up. lol Any ideas what you think it will run? I have no idea because of the slow 1/8th mile time and the high *** mph. Surely it will run a 9 second time slip.

71 chevy

iTrader: (18)

Im guessing 9.30s 9.40s

but dont forget to stay on the tb till it gets over that hump.

Wicked69

Damn that would be cool as hell! Alright, I will stay on the TB. I will also go ahead and set the rev limiter to 4200 for the first pass and see what happens.

atomic 6

You are making some steam, with 118@3800 lbs

But are you going to make it all the way down the 1/4 with the 3.90 gears.

The 118 in the 8th should be 148+ in the quarter.

71 chevy

iTrader: (18)

it will sound something like this when it starts to make the steam and get over that hump



^^^^ good point. if you are running a 28" tall tire you will likely need 7000+ rpm to run the 1/4

trav-tech

iTrader: (1)

I did the math on my setup and my 3.73's and 28" tire with 12% converter slip 7k rpm limit is good for 132mph so im thinking you wont make a full 1/4mile pass on on 3.90's if you are in fact on a 28" tire. youll need something more like a 3.30 gear or so.

Wicked69

I run a 275 hoosier drag radial...hmmm. My rev limiter is set for 6800, I could bump that to 7k but I would be afraid to go any higher. I could try and borrow a set of 30" slicks if I knew somebody....damn.

Wicked69

okay, I heard it.

stock48

iTrader: (17)

Nice pass that thing is showing some big power. Does that engine have the small or big rods?

Wicked69

I have no idea but I know it is the LM7. It was out of a running 2003 totaled out Suburban with 64k miles.

For an update. I think we have the launch part of the tune figured out. We added more timing and did as was suggested and leaned it out to 12.2 off the brake. On my test with the transbrake it build 7lbs of boost. Didn't get a chance to actually run it hard on the street because it was raining. It sucked too because I had an hour and a half drive home and the rain never let up. If the rest of the tune didn't get screwed up, I should be posting a new best on Friday or Saturday night. Going to hold off on the 1/4 until my 275 drag radials run out and I can get some 295/65's.

Thanks for the input from everyone.

98Camarod

iTrader: (43)

At what rpm are you on the brake for the 7lbs of boost?

Wicked69

3400...but I have to use the foot brake to get the rpms up first and then set the transbrake to build boost. If I set there at idle and set the transbrake it will only build about 3-4lbs of boost.

Wicked69

Here is an update. I added the timing into the area where I am on the transbrake and leaned out the fuel table in that area also. It did help. I was able to get a solid 5lbs of boost but that is it. Even after the launch it still seemed to fall on its face a little. I might have the meth injection kicking on too early in the run. Still I drove it to the track with my 6 year old daughter and 7 year old son and their two friends. Made 3 passes and drove it home. Even in this 90+ degree heat and NO intercooler it still managed a 6.49 @ 116 mph! I'll eventually get it there, but I am thinking if the convertor was about 400 rpms looser it would do much better without killing the pass.

I also ran 1lb of less boost tonight. Figured there was no reason to stress the engine all out until I can get the launch much improved.

Bigtoyz

iTrader: (2)

Now this is just something to think about. From what I have come to notice. Is that guys running 3.73 and lower have problems building boost. Some of the problem could be is your not loading the motor down. I run 3.23's and have had no problems building boost. Couple of friends of mine had same issue and went to 3.42 I think they are and did alot better.

Wicked69

This could be but the car went a 1.50 60ft when we first got it finished but with my old loose *** convertor. It was a 5000 stall. A 3.42 is in the mix at some point. Just want to see what I can do with what I have right now. A 3.42 means a new 4 series carrier also. When these tires wear out, I will just try a taller tire first and see if that helps at all. Not for the boost part but just quicker.

71 chevy

iTrader: (18)

the gears might not be optimal, but on the transbrake, the engine does not know what gear is in the rear.

congrats on a new best. i see everything is getting more efficient.

couple of questions.

1. launch rpm
2.afr
3. timing
4. did it hit the 2 step
5. how much time on the tranbrake?
6. did it get over the hump?
7. what are the cam specs again?

its definitely getting better. again, that mph is a 5 sec pass if the 60 were right. and thats a heavy *** street car with a stereo system.

postal14

iTrader: (8)

Are you sitting there kind of holding it on the t-brake and watching it sit at 5 wanting it to go higher? I ask this because you want the turbo accelerating on launch. Lets say you are only getting 5psi on the brake, dont hit 5 and hold it there for a second or two. Get boost climbing and let it go just before 5. Boost climbing on launch really helps.

Meth to early will hurt for sure. This will tie into making you to rich. Especially if its an all off or all on system. Enough meth for rev'd up /spooled up is going to really hurt you trying to get there if it comes on to early.

any freaking tiny *** exhaust leak before the turbos will hurt you BAD.

With a pair of 62's clamped down to 12 psi total your waste gates are probably cracking open on the t-brake. I would probably bet a small amount of money on this one. Thats the same as an exhaust leak, see above. I have no idea for sure what a guy does on the cheap to fix this when you are clamped down to only 12psi. I ran counter pressure to my wastegates with a dail-a-boost set up. Its like a $30 aquarium regulator and u regulate a certain amount of boost pressure to the top of you wastegate diaphragm (<-spell check says that right). This sends boost to the wastegates to keep them shut. Are you running one of these? if not I could explain it more for you.

You probably wouldnt want to mess with this one but what intake centerline is your cam installed at? advancing a cam on a turbo car can help build boost better.

You probably dont want to do this either but a single fogger nozzle jetted for 50hp in your up pipe a few inches before your throttle will straight up bitch slap your turbos into getting off their asses. Its cheap as hell set up and a simple hobbs switch to kill it a few pounds short of set boost level works great and a bottle lasts a long time.

Raising launch rpm, higher stalls ect can really help mask over some stuff. It just plain works. The motor spinning at a higher rpm just isnt as picky or sensitive to some of this stuff.