Lower gears and still slugish.

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71dart318

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I just finished my 8.8 swap. Going from stock 2.76 to 3.73 gears. I have a 71 dart with 318 and a 904. Have several upgrades on motor thought lower gears would make up for lower torque 318. Think the tranny is stock, I serviced it when it was out of the car. New oil an filter. There was some material in the pan but nothing crazy. I can here it shift all gears but its a slug. Can't spin the tires, feels like I'm always taking off in 2nd. Also messed several times with kickdown linkage, still wont work. You guys think tranny might just be wore out? Converter problem? Doesn't rev up like its slipping. This car should be pretty fun to drive with these gears but in barely goes.
 
Are you running DOT approved drag tires with traction devices and a sure grip?? "Several upgrades on motor" means what???? I will tell you a stock 318 2bbl with single exhaust will lay rubber if it has normal radial tires. I think we need more details on the motor.... for instance, a huge cam kills low end torque with a stock converter.
 
Running street tires. My 318 is .30 over with a eddy 7177 cam, eddy aluminum heads, eddy rpm intake, 650 quick fuel carb, long tube headers, full MSD ignition. My 8.8 is a limited slip with 3.73s. I had a 7 1/4 with 2.76s. Taking off from a stop is horrible. Looked like a stock converter, I know a good 2500 stall would help but there is literally no difference with these gears.
 
There are a lot of people here that can help but with the limited info you gave it would all be guess work. that said I'm guessing you have a bigger cam and 4bbl and maybe headers. most likely first thing you need to do is get initial timing some where in the 18-20* BTDC then need to limit total timing to 34-36*. Another thing to check is if you are actually taking off in 2nd. Manually shift into low run it up to around 25-30mph then manually shift to 2nd (did it shift} then run it up to 50-60 and manually shift to drive and make sure it shifts again. if you only get one gear its possible you are leaving in second.
 
Running street tires. My 318 is .30 over with a eddy 7177 cam, eddy aluminum heads, eddy rpm intake, 650 quick fuel carb, long tube headers, full MSD ignition. My 8.8 is a limited slip with 3.73s. I had a 7 1/4 with 2.76s. Taking off from a stop is horrible. Looked like a stock converter, I know a good 2500 stall would help but there is literally no difference with these gears.
You need more than a stock stall to go with the cam, heads, and intake. However, with that build and 3.73's, it should be fast. You need to start from ground zero. ignition timing 1st. Is the valve timing correct? Compression? this list will be long, but it sounds like your way way off on something.....
 
we need to know what your initial timing is and your total timing and what rpm its fully advanced at otherwise we are just guessing and if you don't know for sure what it is it is most likely one of your problems .
 
You say it feels like you are taking of in second... Do you actually feel it shift to all gears?
 
I have been having trouble with timing. Its hard to pin down. added timing tape, running mag pickup in dist. Dist has silver springs on the mechanical advance. Going out in a few and get what its set at right now and let you guys know. The car started instantly before an my dad said I needed to retard it a little. Now it cranks several times before it starts. About the shifts.. I can shift manually into first an second,(when I can find them with this ratchet shifter). let me check timing.
 
One you have verified the engine is in a good state of tune. Compression, ignition timing, carb, no vacuum leaks etc, I would begin looking at the torque converter. If the stator sprag is not holding, there is no torque multiplication going on in the converter & the car will be very sluggish on acceleraton. With your set up & the 3.73 gears you should be painting black lines all day long.
 
soo I went out checked timing. I'm right at 19 degrees@ idle. Drove the car in drive, doesn't matter if I take off slow or full throttle it shifts 1st to 2nd @ around 10mph and 2nd to 3rd @ around 15mph. Seems odd. Also no kick down ever. Have the linkage all the way back. Tried in the middle an forward.
 
Lack of proper adjustment on the kickdown linkage can kill a transmission quickly.
The linkage controls a good deal of the transmission's internal oilpressure.

Linkage all the way back should provide full line pressure, but will most likely give lousy, delayed or rock hard shifts.
 
Does the kick down (throttle pressure) linkage have any spring to it at all when you push back on it? Is it getting any travel from the carb?
 
I have the linkage way back because I could feel the spring back pressure in that area. (dose that make sense). Didn't think it was reaching the kick down area. If I am hard on the throttle shouldn't the transmission hold in each gear longer than normal driving?
 
I don't like it when transmissions shift themselves. I dispensed with the kickdown linkage crap and installed reverse pattern manual valve bodies in everything I owned years ago. Never regretted it. You may have more than one issue, but that stock converter needs to go. Skip the 11 inch and go straight to a 9.5 or 10. Call the converter company of your choice for recommendations. Buy, install and hold on!!
 
I have the linkage way back because I could feel the spring back pressure in that area. (dose that make sense). Didn't think it was reaching the kick down area. If I am hard on the throttle shouldn't the transmission hold in each gear longer than normal driving?

How would the transmission know when you're hard on the throttle, if you've disconnected the linkage between throttle/carb and transmission?
 
Check to see if the throttle pressure linkage is actually operating the lever on the transmission. When you are at WOT, the lever should be all the way rearwards. If this checks out, disconnect the linkage from the lever on the transmission & push the lever rearwards. Release the lever & it must spring back. If not the weld that attaches the segment to the shaft may have broken meaning that the Kick-down valve is not being operated at WOT. I've seen this a few times. It is not advisable to drive around with this condition. A disconnected or non operational TP linkage will toast a transmission very quickly.
 
One you have verified the engine is in a good state of tune. Compression, ignition timing, carb, no vacuum leaks etc, I would begin looking at the torque converter. If the stator sprag is not holding, there is no torque multiplication going on in the converter & the car will be very sluggish on acceleraton. With your set up & the 3.73 gears you should be painting black lines all day long.
With the gear change, you will need a governor change too.
What is your neutral idle speed, and what does it drop to when you put it into gear?
What are the specs on that cam?
I would also jack the wheels off the ground and check for dragging brakes; all corners.
I would also check the line pressure in reverse. At 2000rpm it should max out at 250psi or near it. This will tell you if the pump is any good. I didn't see that anybody asked about a stall test, so I guess that would be good to know as well,.
 
Since you have a ratchet shifter, I'm guessing you aren't concerned with originality. If you can't sort out the kickdown linkage, Lokar and Bouchillon both make kickdown (Throttle pressure) cable kits that are supposedly easy to set up properly.
 
IMO the problem has nothing at all to do with the transmission. It's that big lazy ground Edelbrock cam you have in it. That cam has 308 degrees of total duration so it's a huge cam for a low compression 318 and you need at least a 3000 stall to make it work right. I bet that cam doesn't even start making any power at all in a 318 below 3000 rpm
 
IMO the problem has nothing at all to do with the transmission. It's that big lazy ground Edelbrock cam you have in it. That cam has 308 degrees of total duration so it's a huge cam for a low compression 318 and you need at least a 3000 stall to make it work right. I bet that cam doesn't even start making any power at all in a 318 below 3000 rpm

Oh..Ooooh.... noooo. Throw that cam as far away as you can. That cam has the sloooowest ramps in the world, requiring 74/2 = 37* to climb from .006 to .050.
Edelbrock makes some good stuff but cams ain't one of them. Well that's too harsh.That cam is good for something just not in a streeter.With it's 89* of overlap, it could run like the proverbial scalded cat with open headers, and a well matched Scr.Which would take more than 318 cubes.
But for your combo, that beast is ALLLL wrong.She is costing you HUGE low-rpm cylinder pressure.
Are you sitting down?
Ok, say you have a 3.94 bore,3.31stroke, and pistons down .057. 63 cc heads 5cc eyebrows. an 8.9 cc gasket. Pistons down.057, is 11.4cc
So this totals 661.32 cc swept, and 88.3 cc total chamber, for an SCr of 8.49. So far so good.
But that pig of a cam has these specs; 308/318/112/107. These numbers drop the Dcr so far into the basement, even a lawnmower has more cylinder pressure. Ok, here it comes;5.44/95psi. Let me say it again; 5.44/95psi.
For all calculations, I assumed an altitude of 2000 ft in Vegas. And an ICA of 81* the 050 numbers are 234/244, and lift of 488/510.
The ramps on these lobes are about double of what they should be. Your compression ratio is also fully 2 to 3 points too low for 2000 ft.

Now on the off chance that you brought the pistons up to zero deck , the new chamber size is 76.9, and the Scr climbs to 9.6. The Dcr would then be, hang onto your hat; 6.16/113psi.
And if there were no eyebrows, then 71.9 is the total chamber volume. And the numbers are; 10.2/6.55/122psi
No matter what,that cam has got to goooooooo! In your combo,it is all bark,no bite.
Go now! Drain the water tonight. It's not too late to get started.
 
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