71 Dart / 5.9 Magnum / Procharger

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subcom said:
Did you get a good '60 or 1/8 mile time before the tranny started slipping?
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1.70 60 ft with a 7.50 ET at 94 MPH. I feel like the trans was slipping the whole way and I coasted through the traps after killing 3rd. I'm installing exhaust cut outs this week. I feel like my exhaust is choking this thing. It's 2.5 inch to the mufflers but 2 1/4 after mufflers to the rear bumper. Hopefully get back to the track soon with the new trans and exhaust cutouts. I've also been really conservative with the timing. Really itching to turn it up a little.
 
Walker434 said:
1.70 60 ft with a 7.50 ET at 94 MPH. I feel like the trans was slipping the whole way and I coasted through the traps after killing 3rd. I'm installing exhaust cut outs this week. I feel like my exhaust is choking this thing. It's 2.5 inch to the mufflers but 2 1/4 after mufflers to the rear bumper. Hopefully get back to the track soon with the new trans and exhaust cutouts. I've also been really conservative with the timing. Really itching to turn it up a little.
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That's not bad even with the slipping trans and pretty close to my ET/MPH at 7psi. Once you get the new tranny in and the open exhaust I bet you see some 6.9x in the 1/8th. Also, one thing I noticed (actually calculated) was that my converter slips alots under boost also. You might want to get a good matching converter since the tranny is already out. Mine is an off the shelf 9" PTC 3500.
 
subcom said:
That's not bad even with the slipping trans and pretty close to my ET/MPH at 7psi. Once you get the new tranny in and the open exhaust I bet you see some 6.9x in the 1/8th. Also, one thing I noticed (actually calculated) was that my converter slips alots under boost also. You might want to get a good matching converter since the tranny is already out. Mine is an off the shelf 9" PTC 3500.
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That's what I'm hoping, I'd be happy with 6.90 in the 1/8th.

I talked to Kenny at PTC about the converter. He said to run what I have. It's an Ultimate 3,800 10 inch. Just shows his character, I would have been an easy sell on a new PTC converter but he said mine was a good peice.
 
Walker434 said:
That's what I'm hoping, I'd be happy with 6.90 in the 1/8th.

I talked to Kenny at PTC about the converter. He said to run what I have. It's an Ultimate 3,800 10 inch. Just shows his character, I would have been an easy sell on a new PTC converter but he said mine was a good peice.
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Nice. I had talked to them about my converter slipping and he said send it in and we'll tighten it up. How much? I asked. $125! Can't beat that with a stick! Haven't done it yet cause I don't want to drop my tranny but when I do the converter is going to PTC.
 
Okay, time for an update. Been doing a lot of carb tuning and finally got it sorted out. Got my fuel curve where I want it after going to smaller main air bleeds and different main jets. Still had an off idle lean bog that was finally cured with a 50cc accelerator pump on the primary's.

New PTC built 904 was installed yesterday. Went with a forward manual valve body. Exhaust cutouts are installed. New SS springs installed, new Calvert racing 9 way adjustable shocks installed, new MT SS drag radials installed.

Plan on hitting the 1/8th mile track tomorrow night. Going to make the first pass with exhaust closed then second pass with the headers open. If I still don't have my 6.90s then I'll start inching up on timing.

Only 19 days before I head to drag week so have to get this thing sorted out quick!
 
Went to the track and had more problems. Burnout went fine, launch went fine, pulled hard through 1st shifted into second and nothing was there, hit the rev limiter.

Do I still need to run a throttle pressure cable (kick down cable) with a full manual valve body? It shifts great from 1st to 2nd at certain RPMs. Just acting like a line pressure problem.

I ditched the kick down cable when I installed this new FMVB transmission. Should I put it back on?
 
I don't know much about this and just saw this thread. I thought sprag upgrades were like, mandatory?
 
You shouldn’t need it. My reverse VB didn’t need it. I’m sure someone else here is more knowledgeable about it.
 
Called PTC, he said I shouldn't need the kick down cable since mine is a full manual valve body. He asked me to pull the pan. Here is what I found. Pulled the transmission this morning and taking it to him tomorrow. He is going to rebuild it tomorrow while I wait. Hope it goes better this time. If so, I'll install the transmission this weekend and be back to the track on Tuesday evening.

I feel like I'm doing my own drag week before drag week starts.

Dart 15.jpg
 
ouch….let us know what happened. better luck for the next rebuild! I´ll follow your DW Adventure via the live feed, wish i could be there.

Michael
 
Update: Was at PTC at 7 a.m. this morning when they opened. We tore the tranny down to see what failed. Broke the sprag which in turn broke the case. My dumb *** didn't get a picture. Since the case was broken he talked me into going 727.

He is building me a 727 and a custom converter. He gave me a small block 727 core and building the converter at no charge. He hopes to have it done by Tuesday so I can go get it and put it back in to make a race next Saturday.

Going with a RMVB so I think I'm going to grind my detent on the stock column shifter so I can still run it. Have to get my driveshaft shortened. Anybody know how much longer the 727 is than the 904?

Again, this feels like drag week before drag week.
 
Walker434 said:
Update: Was at PTC at 7 a.m. this morning when they opened. We tore the tranny down to see what failed. Broke the sprag which in turn broke the case. My dumb *** didn't get a picture. Since the case was broken he talked me into going 727.

He is building me a 727 and a custom converter. He gave me a small block 727 core and building the converter at no charge. He hopes to have it done by Tuesday so I can go get it and put it back in to make a race next Saturday.

Going with a RMVB so I think I'm going to grind my detent on the stock column shifter so I can still run it. Have to get my driveshaft shortened. Anybody know how much longer the 727 is than the 904?

Again, this feels like drag week before drag week.
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trans dimension.jpeg
 
I had to do the same thing. RMVB on a 727 is the way to go. I also got an aluminum driveshaft since the length changed.
 
Walker434 said:
Update: Was at PTC at 7 a.m. this morning when they opened. We tore the tranny down to see what failed. Broke the sprag which in turn broke the case. My dumb *** didn't get a picture. Since the case was broken he talked me into going 727.

He is building me a 727 and a custom converter. He gave me a small block 727 core and building the converter at no charge. He hopes to have it done by Tuesday so I can go get it and put it back in to make a race next Saturday.

Going with a RMVB so I think I'm going to grind my detent on the stock column shifter so I can still run it. Have to get my driveshaft shortened. Anybody know how much longer the 727 is than the 904?

Again, this feels like drag week before drag week.
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where are you planning on racing saturday?
 
Austin Boone said:
where are you planning on racing saturday?
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Was hoping to run at Bowling Green on Saturday, but now that won't be possible. Going to Alabama to pick up the 727 tomorrow afternoon so now I'll spend my weekend installing the transmission and new shifter instead of racing. With any luck I'll get one more test n tune on Tuesday night then It's off to Atlanta for drag week.
 
Walker434 said:
Was hoping to run at Bowling Green on Saturday, but now that won't be possible. Going to Alabama to pick up the 727 tomorrow afternoon so now I'll spend my weekend installing the transmission and new shifter instead of racing. With any luck I'll get one more test n tune on Tuesday night then It's off to Atlanta for drag week.
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sweet i’ll have my magnum powered dart at union hill on tuesday
 
Walker434 said:
Was hoping to run at Bowling Green on Saturday, but now that won't be possible. Going to Alabama to pick up the 727 tomorrow afternoon so now I'll spend my weekend installing the transmission and new shifter instead of racing. With any luck I'll get one more test n tune on Tuesday night then It's off to Atlanta for drag week.
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do you have adjustable rockers or longer pushrods to have the eq? heads i was looking into the 2.02 valve ones and didn’t know if i needed them or not
 
Austin Boone said:
do you have adjustable rockers or longer pushrods to have the eq? heads i was looking into the 2.02 valve ones and didn’t know if i needed them or not
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The EQ heads take the same stock valve train as stock heads. I Am running a longer push rod but that's because of my custom ground comp cam. I'm also running Harland Sharp non adjustable roller rockers
 
Well, drag week was fun but a lot of work. Had electronic ignition issues right before DW so I didn't get any testing in until I got there. Long story short, still tuning on this combo. Best pass was at Charlotte, 11.46 @ 119 with a 1.69 60 ft. I think my overall average for 4 tracks (rained out in Atlanta first day) was 11.67. I think my cheap summit 1 5/8 headers are choking the combo. I ordered some TTI 1 7/8 race headers and going to install 3 inch exhaust with pypes race pro mufflers.

Hopefully the new exhaust will get me a 10 second time slip. Also not sure why the car won't 60 ft any better. Has to be the 727 trans or converter. It's not spinning at all. The old naturally aspirated combo had a best 60 ft of 1.54.

I may go back to a 904. I think this 727 is killing the power and the car doesn't seem to like the converter. Oh well, the life of a drag racer I guess. Looking forward to getting this thing in the 10s.
 
Walker434 said:
Well, drag week was fun but a lot of work. Had electronic ignition issues right before DW so I didn't get any testing in until I got there. Long story short, still tuning on this combo. Best pass was at Charlotte, 11.46 @ 119 with a 1.69 60 ft. I think my overall average for 4 tracks (rained out in Atlanta first day) was 11.67. I think my cheap summit 1 5/8 headers are choking the combo. I ordered some TTI 1 7/8 race headers and going to install 3 inch exhaust with pypes race pro mufflers.

Hopefully the new exhaust will get me a 10 second time slip. Also not sure why the car won't 60 ft any better. Has to be the 727 trans or converter. It's not spinning at all. The old naturally aspirated combo had a best 60 ft of 1.54.

I may go back to a 904. I think this 727 is killing the power and the car doesn't seem to like the converter. Oh well, the life of a drag racer I guess. Looking forward to getting this thing in the 10s.
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The bigger trans is going to rob some power but you get the converter right you will get the 60' down I'm sure how much boost is it making right now.
 
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