Any perdictions on times?

**freaky57fast** · 02-26-2014, 05:06 PM

I finally had achance last fall to make runs on my car after owning it for around 16months. I was a little disappointed on my times (hooking up was an issue) So this year I was planning on going to a quarter mile track and was going to do some suspension workings. the mods I had in mind are relocating the torque arm, getting a new torque arm, panhard bar, sfc, and tires. I have lid bellows long tubes ory and lm1 along with auto and 12 bolt 3.73 gears. any idea what I would run if I could launch good and what brands should I look at that are reliable? anything I missed feel free to lend me advice on, I do drive the car a bit so no v6 springs or any of that but any other suspension stuff I could use?

**pajeff02** · 02-26-2014, 05:19 PM

Our car went from a stock best of 13.4 to a 12.88 with supension mods, 3.73's, exhaust, tune and track tires.

**Firebirdjones** · 02-27-2014, 04:18 AM

If it were mine I'd do a converter in that thing pronto. With some tires to make it easier to drive, it would easily be in the 12's.

My SS convertable with a 3400 stall, headers, and my tune, everything else stock including the suspension, tires and exhaust, went 12.76 with a 1.90 60 foot. With better rubber the car was capable of 1.7-1.8 60's and likely would go 12.50's.

The auto equipped LS1's are pretty easy to dip into the 12's with minimal work, and without all the expensive suspension stuff.

**pajeff02** · 02-27-2014, 08:37 AM

Dan's SS went 12.98 with an exhaust, gears and a tune on a day with good air. Ours dropped another 4/10ths when I added the 3,200 stall converter.

**Firebirdjones** · 02-27-2014, 08:53 AM

I figured yours was a bit quicker than the first time posted. Converters make a world of difference.

**pajeff02** · 02-27-2014, 11:51 AM

The converter was absolutely the best bang for the buck - fastest time now for our car is a 12.43 with the stock power plant.

**freaky57fast** · 02-28-2014, 05:17 AM

Originally Posted by Firebirdjones

If it were mine I'd do a converter in that thing pronto. With some tires to make it easier to drive, it would easily be in the 12's.

My SS convertable with a 3400 stall, headers, and my tune, everything else stock including the suspension, tires and exhaust, went 12.76 with a 1.90 60 foot. With better rubber the car was capable of 1.7-1.8 60's and likely would go 12.50's.

The auto equipped LS1's are pretty easy to dip into the 12's with minimal work, and without all the expensive suspension stuff.

Forgot to say converter, what brand is yours? Everyone tells me yank and no lower than 3500 is that good advice to follow. Also how hard is a stall on the 4l60? I don't wanna make six passes a weekend then driving to work lose my trans in the middle of main street haha.

**freaky57fast** · 02-28-2014, 05:21 AM

Also will I need to tune the car immediately after the converter or can I wait until I get a new cam? Was trying to go with one this winter but hunting trips and looking to buy a house got in the way/money got tight

**Firebirdjones** · 02-28-2014, 06:14 AM

I understand the money thing, and certainly a house is more important.

Yank is a good recommendation, and something in the 3500 range is a good all around driver/track day converter. The most popular brand converter I've seen among the 4th gen crowd is the Vigilante from Precision Industries. Some of the quicker street cars I see at the track always seem to have these. But at about $900 they aren't cheap for some people.
I ran a Fuddle that cost me about $700 at the time (several years ago) but I prefered to upgrade to the larger clutch and clutch face for stronger lockup with the intent of locking it up under load. Most of your cheaper $500 converters use the stock sized lockup clutch, which would work fine for most any street car.

As far as a tune it depends on the converter. Some are loose enough to set off the engine misfire codes and fall into limp mode because the computer thinks the trans is slipping. Depends on how aggressive the particular converter is with STR. My 3400 with a 2.1 STR set off the engine misfire codes imediately, so I had to go into the tune and tame down engine misfire sensitivity about 50%.

**freaky57fast** · 03-02-2014, 06:26 PM

Originally Posted by Firebirdjones

I understand the money thing, and certainly a house is more important.

Yank is a good recommendation, and something in the 3500 range is a good all around driver/track day converter. The most popular brand converter I've seen among the 4th gen crowd is the Vigilante from Precision Industries. Some of the quicker street cars I see at the track always seem to have these. But at about $900 they aren't cheap for some people.
I ran a Fuddle that cost me about $700 at the time (several years ago) but I prefered to upgrade to the larger clutch and clutch face for stronger lockup with the intent of locking it up under load. Most of your cheaper $500 converters use the stock sized lockup clutch, which would work fine for most any street car.

As far as a tune it depends on the converter. Some are loose enough to set off the engine misfire codes and fall into limp mode because the computer thinks the trans is slipping. Depends on how aggressive the particular converter is with STR. My 3400 with a 2.1 STR set off the engine misfire codes imediately, so I had to go into the tune and tame down engine misfire sensitivity about 50%.

How do I figure out a converters str?

**Firebirdjones** · 03-03-2014, 03:42 AM

A good converter manufacture will figure it out for you. You can have 2 converters with the same stall rating of 3500 but have 2 different STR's which will make them act completely different from one another.

Once you give them info on the car like weight, cam, gears, dyno numbers, etc....a good converter company can then build one to suit that car specifically.

**freaky57fast** · 03-05-2014, 02:25 PM

Originally Posted by Firebirdjones

A good converter manufacture will figure it out for you. You can have 2 converters with the same stall rating of 3500 but have 2 different STR's which will make them act completely different from one another.

Once you give them info on the car like weight, cam, gears, dyno numbers, etc....a good converter company can then build one to suit that car specifically.

Does str make a huge difference because I don't have a cam yet or dyno numbers. So will a stall on my car affect town driving? Or will I just pull more rpms to get going?

**pajeff02** · 03-05-2014, 04:55 PM

At first it's a bit odd as you do rev it up more to get moving - kind of like letting out a clutch really. After a while you won't even notice it. We street drive ours with a 3,200 and have had zero issues. Just make darn certain that you install an auxillary transmission cooler.

**Firebirdjones** · 03-06-2014, 04:13 AM

Hard to explain, but in short, the STR affects how hard or soft the converter hits when it flashes, is one way to put it.

**freaky57fast** · 03-06-2014, 08:02 AM

So I won't be peeling tires at stop lights OK cool. So what str do most converters have stock?

**freaky57fast** · 03-06-2014, 08:05 AM

Also how long does it take to swap out with a lift? And does it make my WO start at say 3500? Like back to the power band?

**Firebirdjones** · 03-06-2014, 08:45 AM

On the lift I can swap a converter in a couple hours with a break in between.

I think you are asking wide open throttle?? That is going to be different with each car. The stall number that a manufacture advertises is just a rough estimate. All kinds of things affect where the converter will flash including things like, rear gear, car weight, engine torque, camshaft profile, etc... But the number gives you a good idea of where it might be.

Since LS1's are soft on torque below 4,000 rpms, it takes a pretty loose converter to get the engine up where it makes power. That's why most recommend something in the 3500 range to start with. It will drive around fairly normal, and it still has lockup at 40 mph so any speed after the converter locks is just like a stock converter. It's when you mash on the go pedal the converter will flash up, and things get fun

**freaky57fast** · 03-06-2014, 09:36 AM

Originally Posted by Firebirdjones

On the lift I can swap a converter in a couple hours with a break in between.

I think you are asking wide open throttle?? That is going to be different with each car. The stall number that a manufacture advertises is just a rough estimate. All kinds of things affect where the converter will flash including things like, rear gear, car weight, engine torque, camshaft profile, etc... But the number gives you a good idea of where it might be.

Since LS1's are soft on torque below 4,000 rpms, it takes a pretty loose converter to get the engine up where it makes power. That's why most recommend something in the 3500 range to start with. It will drive around fairly normal, and it still has lockup at 40 mph so any speed after the converter locks is just like a stock converter. It's when you mash on the go pedal the converter will flash up, and things get fun

I was talking wide open throttle good guess lol. cool so its no something im going to be messing with a whole weekend. thanks for all the advice guys you rock!

**pajeff02** · 03-06-2014, 01:17 PM

Swapping it out isn't too bad really on a lift. The very top bolt and the next one or two down on the driver side were a bit tight to get to. I also had an issue with the transmission hanging up on the dowel pins. I ended up using a blunt tip in my air chisel to push the pin out of the block. Before reinstallation, I used emery cloth to clean the pin and then applied a coat of anti-seize. There are a pile of pics in my Performabuilt thread of the process.