dschmittie1

iTrader: (64)

Right now I am about 3000rpm @65 and 3500rpm@75mph

I think the converter is too loose. There is no way I should have been running out of gear at 141mph with 28s and 3.70 gears. I hit the revlimiter(7100rpm) in 3rd right at the traps. I need to look at my logs tonight and see how much converter slip I am having.

351carlo

Well you're not going 141mph through the traps, you're going a bit faster than that.

If you're converter is slipping more than 5 percent or so, your effective RPM would be about 6700 with a 7100 motor RPM. Assuming a true 28" tire, you should be hitting about 150 on the top end. Now what you're averaging over the last 66' is what gets reported as your 1/4 MPH.

Agreed that you should have a few more MPH left, but not much. If the converter is slipping more it's either time for a more efficient converter or a 3.5x gear set.

dschmittie1

iTrader: (64)

it is a 28x10.5 ET street.

351carlo

Sure it's a 28x10.5 ET Street? I see a 28x11.5 and a 27x10.5 listed, but can't find any listing of a 28x10.5 ET Street.

youngrigo

Is that what the mods in your sig?

2ktransam

iTrader: (12)

Your rpm does seem a little high. I have 28's and 3.73's and I gett 12% slip with my converter. 132mph is 6600 in my car and I get about 5-6mph for every 100rpms so mine would be around 150-154 at 7100. Your converter must be slipping a ton with all that power.

Zturd

iTrader: (12)

See everyone.... get rid of the 6spds.... we need more people doing this due to the 6spd guys that can't drive giving us bad names. You too can drop a half a second going from a shitty 6spd driver to a auto

P.S. Lt. Dan approved this message!!!

dschmittie1

iTrader: (64)

I think it was 28x11.5 I will check tonight for sure.



The car is a forged 347. home ported 243 heads with a 1.60 exhaust valve, victor JR intake, 235/251 .621/.624 115 blower cam, and a TH400 now

dschmittie1

iTrader: (64)

Yeah ok. You can't say that you haven't had your fair share of 6spd related breakages and failures.

351carlo

12% calculates for your setup. 6600 with no slip would be 147 with 3.73s, 28" tires and a 1:1 ratio. With converter slip accounted for it's 132.

Now since we're guess-timating the tire growth, and since the MPH we're calculating is the exact 1320' MPH not the average 1254'-1320' MPH like they give you, we're in the ball park.

Your setup at 7100 however would only be 142 mph or so.

Just assuming he was at 7100 and the trap speed was 141:

Trap speed with no slip - 159.85 mph
RPMs with no slip @ 141mph - 6275

Approximate converter slip : 11.5%

It's all straight forward math. The only variables here are the converter slip percentage, and the actual diameter of the tires.

(Yep, another worthless bunch of math. But it's either I type this **** or I do work.)

351carlo

Hey man, how's your quest for 10s going with the C6Z?

-Shitty 6 Spd Ford Driver

dschmittie1

iTrader: (64)

So would you say 12% slp is too much. I am gonna look at my mph vs rpm in my data logs tonight.

a tighter converter or a gear change would make this nice to drive on the street.

2ktransam

iTrader: (12)

LOL I have dropped 1.1 seconds off of my best 6spd pass so far.

JL ws-6

iTrader: (50)

that's way too much, I am going thru the traps with a 3.73 and a 28x10.5S tire and seeing under 6800. You're blowing right thru that thing, get it tightened up some and I bet it picks up even more. You probably have 9.0 potential once you get that sorted.

2ktransam

iTrader: (12)

I don't think it is just simple math with a slipping converter. At 6000 rpms i'm doing 96mph wich is 30% slip. I think tipically a converter gets more effecient as they go up in rpms. I gain 36mph from 6000-6600 because the converter slips less the higher I wind it.

Dan, the more power you put into that coverter the more it is going to slip so you might need to have it tightened up some. What converter is it?

SLOW30th-TA

iTrader: (29)

You have changed your setup quite a few times (cams, trans, intake)? What intake elbow did you go with, does it clear the cowl, any pics?

What happened to the T56 (damages/ draw backs)?

I have a lot of questions as I am building the same thing however it has been put on hold with buying a house.

dschmittie1

iTrader: (64)

Well last year I was stock heads a smaller cam and ls6 intake still the forged motor. I had the t56 in it then although I did do some upgrades to it. I went 10.33@136 with that setup. made 676rwhp and 590 rwtq. The reason for the swtich was needed a new clutch and looking at $1500 clutches and I got a complete swap for $1700.

I have a intakeelbows.com elbow and I had to shim the k member down just a bit to clear the hood.

ScreaminRedZ

iTrader: (3)

Congrats man, 9's are no joke!

dschmittie1

iTrader: (64)

Well looking at my logs I am showing 6400rpm @ 147mph I am not 100% sure how acurate the speedo is but that is the mph and rpm that I let out of the throttle.

I guess I still have more room for improvement.

JL ws-6

iTrader: (50)

That mph is jacked. I've never seen a TH400 swap actually have the speedo work right.

6400 rom doesn't make sense either, that could be right... do you have a tach in the car? What is it saying going thru the traps, not the factory one because that's totally useless..