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Post your 12 second combos

Hi guys, sorry for delay.

I'm running Mickey Thompson pro bracket radials 28 tall x 9 wide, 13-16 psi. It hooks good and does not lose traction at launch. The tires wrinkle and seem to stay glued. I have increased tire pressure to 18 psi and it did spin pretty good st the line. MT tech line told me 13-16psi for MT PBRs....I shift at 5500 rpm and go thru the lights at roughly 6200 rpm.

The car pulls strong thru the 1/8 th but beyond that it seems to lay down. It doesn't pull hard beyond the 1000 foot mark. Its not wimpy, just stops pulling. No misses or sputtering. Throttle response is excellent. The car does not have a cage as of yet. I'm still contemplating whether to install a cage on a real RS vert. I'm not worried about getting kicked out of track yet. I also think I should be mid to high 11s. I get 7-8 psi at fuel regulator and carb seems right on.

Do u guys think the 60 foot time reflects a 11 sec car? I think the cam is small at 509. I used to have 915 heads un ported and it ran 12.20-12.30s. Adding aluminum SEZs and roller rockers, it dropped to 12.07. But, I'm not overly thrilled at 12 00s either.

Currently, I have approximately 11.5 to 1 compression, give or take. I did not actually measure comp. I'm running 039" head gasket, about .010 in the hole at TDC, with 75cc chambers. Race Tec catalogue and tech info puts me at approximately 11.5 to 1 w/ .060 over flat tops.

-Blake
If you take a look at my post no 157. I have the same issue, feels slow at the top end.
I will swap my hydraulic cam with a solid at 250-260 at. 050 and 0.55-0.6 lift.
 
what RPM are you leaving the line @ and its a foot brake right? also can you shift @ 6500

I hold it to 2500 rpm at the line, the converter is actually a 2800-3200 stall, 10" converter from A and A transmission. (Not 3400, in my original post I was incorrect, my apologies).

Hi moparcrazy,
So, the converter is a 10" unit, 2800-3200. And I can hold it to 2500 before I feel it creepin thru the brakes. I could shift at 6500 I suppose. But to be honest, i dont feel like it's pulling beyond 5500.

Thanks,

Blake
 
Wallace calculators says 1.67 60ft translates to an ideal 12.02 at 110 and change, says a 7.65 translates to an ideal12.10 at 109. Looks like you are doing okay! Whether more cam gets you more topend, who knows? Maybe you have too much gear for the top of the rev range for a hydraulic cam? Maybe your 509 isn't stable at 6200 in the lights.
 
I hold it to 2500 rpm at the line, the converter is actually a 2800-3200 stall, 10" converter from A and A transmission. (Not 3400, in my original post I was incorrect, my apologies).

Hi moparcrazy,
So, the converter is a 10" unit, 2800-3200. And I can hold it to 2500 before I feel it creepin thru the brakes. I could shift at 6500 I suppose. But to be honest, i dont feel like it's pulling beyond 5500.

Thanks,

Blake
I would ditch the TorkerII intake, Like other B Bodies I bet that you don't have much extra hood clearance. On my 69 I went with a M1 open intake and a drop base and 3" filter and it worked for me. I would call Dave at Hughes engines and get a camshaft. That MP 509 is out dated, and I don't believe these parts match your heads. I will guess that you will need a little more stall in your converter.
 
Thanks all for the suggestions. I appreciate the awesome help and enjoy researching the forums.

For the 2020 year, I will have to leave the motor alone since it’s still new. I do however have fiberglass bumpers and fiberglass hood and cool lingenfelter front brackets for the offseason. Yet to install. So, I do look forward to that.

Thanks all,

Blake
 
how are you passing tech i think any covert. needs a roll bar if it goes faster then 13:99 your is a beauty
 
how are you passing tech i think any covert. needs a roll bar if it goes faster then 13:99 your is a beauty

Local track doesn’t bat an eye at my car for Friday nite test n tune or bracket racing on Saturdays. I’ve never ran at big events, i stay pretty low key. As long as I’m not behaving like an idiot, they wave me thru.

Thanks for the compliment. I’m 33 years old and have been wrenching on the ole girl since I was a teenager. It’s my passion.

Thanks,

Blake
 
I hold it to 2500 rpm at the line, the converter is actually a 2800-3200 stall, 10" converter from A and A transmission. (Not 3400, in my original post I was incorrect, my apologies).

Hi moparcrazy,
So, the converter is a 10" unit, 2800-3200. And I can hold it to 2500 before I feel it creepin thru the brakes. I could shift at 6500 I suppose. But to be honest, i dont feel like it's pulling beyond 5500.

Thanks,

Blake
do you have a fuel pressure gauge on your pump where you see it at high RPM, mine would drop down to 3 pounds, after I fixed it, it pulled like a locomotive to 7200 RPMs, & thats where I shift ! also recommend a AFR "Air Fuel Ratio" gauge so that you can tune that carb !! do you have a Manuel valve body ?
 
Moparcrazy,

Fuel pressure gauge located at the feed lines under hood. I'm not able to see gage while driving. I get pretty good pressure at the gage. I can regulate it all the way to up to 12 psi, but I keep it set to 7-9 psi. Summit elect fuel pump ( brand new unit, 140 GPH), -8 Russell lines. I do have a turbo action cheetah reverse manual valve body and PPP shifter.

Thanks,

Blake
 
Moparcrazy,

Fuel pressure gauge located at the feed lines under hood. I'm not able to see gage while driving. I get pretty good pressure at the gage. I can regulate it all the way to up to 12 psi, but I keep it set to 7-9 psi. Summit elect fuel pump ( brand new unit, 140 GPH), -8 Russell lines. I do have a turbo action cheetah reverse manual valve body and PPP shifter.

Thanks,

Blake
IMO you should put a fuel gauge where you can see it especially if your car isn't pulling up top.
you can check where your torque converter is stalling by putting it in 3rd gear at a complete stop, hold the break hard to hold the car, then flooring it, it will flash to exactly where its stalling, 3400 or what ever it is.
I spent $500. on my fuel pump & $300. on my regulator & my fuel pump was bad only after 4 month's, thanks to my fuel pressure gauge I could see what was happening.
 
Do u guys think the 60 foot time reflects a 11 sec car? I think the cam is small at 509.

Maybe, but your mph does not, IMO. I don't think your problem is tires or converter to get a better 60 ft. I think it's a little short on power. You can keep chasing better 60ft and maybe get there, but instead maybe look for more power.

The car is heavy, and that convertible chassis is probably eating up horsepower too. But even with those two factors working against you, I would think your mph (horsepower) would maybe be a little higher.

Check the fuel pressure as someone said, at WOT. Try running it without the mufflers. A bad converter can eat a bunch of power too. Or maybe there are a couple of little things off in the tune

I would think a 4200 lb race weight in a regular B body with how your's is equipped should be running 112-113 in the spring or fall at an Ohio track and be in the 11.8's

All that said, it would probably like a different cam.
 
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Thanks all for the suggestions. I appreciate the awesome help and enjoy researching the forums.

For the 2020 year, I will have to leave the motor alone since it’s still new. I do however have fiberglass bumpers and fiberglass hood and cool lingenfelter front brackets for the offseason. Yet to install. So, I do look forward to that.

Thanks all,

Blake
Leave those nice bumpers on. What you have is decent compression. Not crazy about the intake, but. The big issue I see is lack of converter, then cam. You have race style heads and compression. Mismatched to a street cam and converter. To compare we run a street 65 Belvedere. Eddy heads (stock), lousy Weiand 2x4 low rise intake with 2 600 eddy carbs, 10.0-1 compression,.557 Mopar purple shaft solid,410, headers. So with less head, intake/carb maybe a wash. Or yours a touch better. We run more cam and way more converter. Runs 11.30s@117. How much can a converter be worth? My street car ran 11.7@122 with a 3000 flash. Swapped to 5300 (which street drives fine) it picked up to 11.0@123. Call Lenny at PTC and get a real converter. After that Id be upping the cam. You own an easy 11 second car.
Doug
 
Thanks for the info, I appreciate all the help.

We ll see what I can do this winter.
 
UPDATE on my car this spring made a few changes to my car still a stock bottom 72 imperial motor but swapped heads out to Eddy E heads and changed to a 3800 stall Coan converter the only 2 changes I made to car same .509 cam and 3.91 gears and went from a best of 13.18 to a 12.50 at 108 mph through the muffs.Best 60ft 1.69 leaving about 1700 still tuning hoping to get a tenth or 2 more out of it.Carb is an 800 Holley Dbl pumper and MT 255 drag radial.
 
Congrats, that's a big jump.
Thanks never thought it would run that good for a 440 that sat for ten yrs in my garage and how many before I picked it up the guy I picked it up from said it had 50,000 miles on it when pulled.
 
Raced the "Tan car" at National Trail Raceway 2 weeks ago. Had a fuel pressure problem and came up with a shitbox engineering solution and was pleased with the outcome. This is a stock Max Wedge engine that's been in the car since 1991 along with the trans and converter (10" Coan), 2" Hooker headers, 4.56 gears and 9" M/T radial slicks. Ended up with a 12.33 at only 105 mph due to the restricted fuel pressure. I'm thinking the fuel pump has seen better days since it's been in there since 91 also. The car has been sitting for many years. Came up with a hillbilly throttle stop that seemed to help me get through the weekend.

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Wow that's really keeping up with social distances you parked way out there.. Lol
 
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