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Discussion Starter #1
Can you look over my combo, and see what I'm missing?

3200 lbs w/me

31 x 16.50 MT E.T. streets

4.86 9"

T400, TCI group 6 8" conv., brake

421 sbc, AFR 220s flowing 292 @ 6 - 303 @ 7

Victor Dom Int., 1100 dom, no spacer.

W/1.6 rockers, 714 - 688 276 - 284 110 lsa

13.2 : 1 comp.

6" rod, H Beam

Ross Pistons

Today, only got 1 pass due to rain, and went 101.1 & 127.3 with 38-39 * timing, but it seems to like 40-42 better, starts easier, more responsive etc..... I had it set for street driving on a pump gas/race gas mix, so I thought I would run it and see how it liked less timing, but my low #s were off.

Truck is running 10.70s at 124-127 depending on the track, my 60' times seem dismal, 1.53 best leaving at 5000 on the 2 step, were 1.6s leaving at 4200.

Truck runs great, no misses, no problems, feels clean, sounds clean on the vids.

I see others w/similar combos running much better e.ts, I feel like I'm missing something here.

I'm shifting at 7200, but it seems to want to keep pulling past that, say if I over rev 1st, it never lays down. I've had other combos that you could really feel when you went past their powerband.

Any advice/or thoughts will be appreciated.

Here is a vid from today

www.karsxtremeperf.com/videos/MOV02350.MPG
 

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Can you post the incrimentals from the time sheet?

You have a typo on your first ET mentioned up there. Tell me what it ran.

Also, what is the converter doing, on the launch, on the shift, etc.
 

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Discussion Starter #3
O.K.,

60' = 1.5952

330' = 4.4850

1/8th = 6.9091

1/8th mph = 101.10

1/4 = 10.7701

1/4 mph = 127.14

Sorry, no 1000' #s. This is an older track. But its a relaxed atmosphere.

Here are the #s from another track a week and a half earlier.

60' = 1.543

330' = 4.431

1/8th = 6.856

mph = 100.54

1000' = 8.974

1/4 = 10.786

mph = 123.86

I had my "Air Pan" on and I think this is where some mph went.

Now as far as the converter goes, it seems to not want to flash much. As I said, I was running 1.6 60s, then I bumped my starting line rpm from 4200 to 5000, and picked up over a tenth in the 60'.

If you listen to the truck on a pass, the rpms seem to be consistent on the shifts, they drop and recover in proportion to the acceleration.

I've never had a car with this power before, so maybe I'm not answering your question the way you want, the converter seems to be working fine, but I think its a bit tight. On the 127 mph pass, I crossed the line at 7400 rpm., if that tells you anything.
 

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One thing i see in the vid is the right rear is sitting on the tires when you leave. There really should be some extension there. You 60' should be 1.43 with a 127 mph... So IMO you need to look in the suspension some. I feel the mph is lazy for your combo but wait and see what chris says he is much more experianced then me......

Is that a ladder bar truck????

keith
 

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Actually it should rise more. Next time you run it get a vid from the right side rear. look close on single frame and the rear fender opening should rise 1" or so away from the rear tire. It looks like it's rolling back on the tire (squatting) the way it is now...
 

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Yes by the body lifting in the rear it will plant the tire, IE Weight transfer. I am no expert with ladder bars. I am a stock suspension guy... So someone with ladder bar knowledge will need to jump in here. But i would look into the front suspension for correct springs ,shocks etc... also did you calculate you instant center of the truck or was it all set up when you bought it????

what rear shocks??? And where are they set????

Go out and lift the front of the truck at the fender you should be able to lift the body a easy 2/3 inches.....

keith
 

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The rear should separate from the body, or at the very least remain in a steady position. This is loading the rear end down onto the track. If the body is dropping over the tire on the launch, this indicates that you are 'unloading' the tire from the track.... it's trying to yank the rear tire off the track, but obviously gravity prevails and the car sinks.

Any ladder bar suspension should have a double adjustable rear shock. This way you can control the AMOUNT the rear end loads the pavement, and then you can control how long it remains that way by allowing it to unload over a period of time after this initial hit.

Also... Most people put too much rear spring into the rear suspension of a ladder bar car. Springs are cheap for coil over setups so give some thought to a low rear spring rate.

I'm with Kieth the mph seems soft but I haven't sat down and tried to calculate anything yet... I'll do some posting later on it. But your 60' is hurting you by 1.5-2 tenths on the big end, and we haven't even addressed the converter yet.... which could be a major player in ET.

Myself I would concentrate on the truck itself before I tried to address anything in the engine. Because anything you do with the engine is going to be masked by chassis and converter/trans issues. As long as the engine is healthy, it's best to work on making the car the best it can be first....
 

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Okay.

I couldn't watch the video from work. The first thing I hear going down the track, is that for a 3 speed... it's really staying in the coverter too long. It's loading the engine down, and shift recovery doesn't 'sound' that great... Can you hear it?? It's just not accelerating on the gear changes for a good couple seconds... by the time it starts accelerating you're ready to shift into another gear creating the whole scenario over again, and then on the 2-3 change it's not accelerating until you're in the traps. And by accelerating I mean hard acceleration... no reason for what I assume to be a 3 7/8" stroke arm not to accelerate.

So I see 2 things from that video. First, the truck leaves like a stone. The thing just doesn't react. It leaves like the suspension both front and rear is very tight. So there is a couple tenths. And second, that converter just doesn't sound right going down the track... and that could also be hurting the launch. So, I would concentrate on converter and suspension.

I might start suggesting things like camshaft and such, but a converter swap is easier, and regardless of the engine, the suspension needs to be worked out.
 

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Discussion Starter #12
Kool, please note, that cashflow is not unlimited....well, lets say fairly LIMITED at this time, so the motor will need to stay as is, but it sounds like you see what I feel.

The only time the truck ever put me hard into the seat was when I left on a 225 hit.

I am able to push the rear of the truck down a couple of inches by hand, but the front I can barely move, BUT, on the street it seems to move thru the suspension O.K.

My front shocks are QA1 coil-overs that mesh a stock upper spring mount to a coil-over shock, so I could retain my stock setup. I have the adj. knob set at a 7 click setting, and it goes to 12. I was worried about the front coming down too hard on the exhaust.

My rear shocks are just a set of Koni coil-overs, non adjustable.

I'm not happy with this converter, and was told I prolly wouldn't be, but 2 friends are running similar small blks with this same converter with much better 60s than me. 1 car is much heavier, the other is a tad lighter.

94, I have a Mallory 140, I'm carrying 6.5-7 psi in the traps.
 

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Again, I tell folks this all the time, but it ends up just going in the 'thanks' box and never gets a second thought.

If the engine is healthy, forget about it and work on the car. Guys like to beat the engine to death trying carburetors, timing adjustments, camshafts, intakes, etc.... all the focus is under the hood. Close the hood, and work on the suspension. The cam may not be perfect, but the combination is not something way off in neverland.

It sounds like this might be somewhat a street car?? If not, then I would bet that all sorted out, that truck could 60 in the high 1.3's.... with the right gearing, the right converter, and last but definitely not least, the right shocks. You ever pay attention to a Stock Eliminator car? The A/Stock Automatic guys ...They 60 foot in the 1.25 range.... running low 10's....

SHOCKS SHOCKS SHOCKS.... it is ALL about shocks. If you have a wish list of stuff to get for the truck, put shocks at the TOP. Double adjustable in the rear, and you can live with single adjustable in the front.

For a torque converter, get a hold of Kenny Ford at PTC. I can't find the number right now but I'm sure you can dig it up. He's reasonable in price compared to others, and his stuff seems to work.

Shocks and Converter and I'd say you would be able to get that thing leaving, and accelerating on the shift like it should.
 

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Discussion Starter #14
Wow, I just never realized the critical importance of shocks.

But, it makes sense.

I think I'll start there, then see about a converter.

Do you have a particular shock you like?

1.3s, damn, that would certainly wake that thing up!!!!

I've always felt mid 1.4s shouldn't even be a question.

Hell, this motor went 1.47 in a stock suspension 'Bu w/28" tires and a 4.56, and T350! Odd it had a 3000 converter, but it flashed much higher. It went 10.70s then.
 

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I like Strange Shocks. Dbl. adjustable rears, single adjustable fronts are good.

There are a host of others as well. Afco, Koni are 2 of the best, but the Strange might be a tad cheaper.... you'll have to price them out.
 

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No on the rear I'd probably start with extension full loose, and compression maybe in the middle... to tight. This will allow the suspension to load the rear tires as hard as possible, and the compression tight will not allow it to unload... I don't know how much your truck will wheel stand and such so I can't comment on the front... but from the looks of the launch it needs to be loose.
 

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Discussion Starter #18
Kool,

I'm going to get the shocks today, and go out Wed. nite, so I'll find out.

Now on the front, my exh. is sooo close to the ground, really can't let it pull the wheels more than a few inches, as a smashed exh would be a calamity at this time.

The front shocks are single adjustable, so that controls rebound only correct? So if thats the case, then I should leave them alone, or will loosening rebound help with the launch?
 
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