71 Dart / 5.9 Magnum / Procharger

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mderoy340 said:
IMO you're going to need a NHRA license and more safety equipment with the new motor.
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Yeah, trying to go 10.0's at drag week. The weather is usually really hot and humid in September especially in the afternoon when my class gets to make passes. Car will need to be capable of 9.80's or 9.90's in order to do consistent 10.0's at drag week. But I'll only be legal at 10 flat. The nice thing is I should be de-tuning the car to run my 10.0's not pushing it to it's limits like the magnum. Less timing and less boost, also adding an intercooler this time.
 
The oil in the cylinder came in from the HG blowing the small blocks need that one more head bolt in that area. The block deck is factory machine surface right?
 
subcom said:
Yet another blown head gasket. I guess it's a boost initiation ritual for us magnum guys.

I don't know the why they blow but my observation is that it seems to always include the outer most cylinders, like #1 and #7 or #2 and #8. Look at Dusted's pic above. I seem to recall that it is also those cylinders on the factory Magnum heads that tend to have the cracked valve seats between the exhaust and intake valves....or at least the cracks are the most severe on the far ends. I wonder if it's not a weak cooling issue on those cylinders? I'm convinced my head gaskets blew not long after I had a couple of over-heating issues on my build possibly weakening the gasket material.

I hope that's the extent of the damage and you're able to get it back together and on the road. -subcom
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Would you guys like to know the reason it blows out the outermost cylinders???

Its the carb hat. It will make distribution uneven because of the air velocity coming through the hat. We killed 5 motors before Steve Brule from Westech fixed it 10 minutes, we stood there jaws on the floor. He did a partial pull with 8 O2 sensors in the header primary tubes. He aborted the run and showed us what was happening. 10 jet sizes bigger on the right rear and the motor still runs today with over 800whp. BTW to the OP I went to 2017 Drag Week in my Torino and met you and saw your car. Its such a cool car I hope to see you at 2019 Dragweek and see you running in the 10's.
 
rdakota340 said:
The oil in the cylinder came in from the HG blowing the small blocks need that one more head bolt in that area. The block deck is factory machine surface right?
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The 4 bolt theory is a myth. Ford small blocks have 4 bolts per cylinder and they boost the crap out of their stuff, Hell there is a Fox body that runs drag week with a small Ford that runs low 7's with a single turbo.
 
turbodart68 said:
Would you guys like to know the reason it blows out the outermost cylinders???

Its the carb hat. It will make distribution uneven because of the air velocity coming through the hat. We killed 5 motors before Steve Brule from Westech fixed it 10 minutes, we stood there jaws on the floor. He did a partial pull with 8 O2 sensors in the header primary tubes. He aborted the run and showed us what was happening. 10 jet sizes bigger on the right rear and the motor still runs today with over 800whp. BTW to the OP I went to 2017 Drag Week in my Torino and met you and saw your car. Its such a cool car I hope to see you at 2019 Dragweek and see you running in the 10's.
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Yes, I remember meeting you. I was going to send you a PM about what you said on jetting the right rear up but your inbox is full. I'd love to talk with you more about this and get some more details. I don't want the same thing happening with the new engine.
 
turbodart68 said:
Done. I also participated in the Hanger 18 carb modifications. I had the original carb he and I modified. He later went on to write that article.
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A huge thank you for that information! I modified the duster carb and the truck carb from that page. Thank you!
 
dusted said:
A huge thank you for that information! I modified the duster carb and the truck carb from that page. Thank you!
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Thanks for that. I can't take credit for it, I just happened to be the guy with a blow through carb and then Andy and I reversed engineered it. He then took it to the next level since he ran a machine shop and is a very talented machinist and fabricator.
 
Okay time for an update. Got the new engine and transmission in this weekend. 360 block bored 60 over with a mopar performance forged 4.0 inch crank. CP Carillo Boost pistons, forged H beam rods, Indy TA Heads ported by Brian at IMM, Victor 340 intake ported by Brian at IMM, Isky cam .528/.525 lift 242/252 duration at .050 on a 114 LSA.

Should be a beast! I think I'm going to run it naturally aspirated for a few passes then install the procharger. I hope to have everything lined out and make several low 10 second passes before drag week this year.

Dart 18.jpg
 
Awesome bro! Awesome!

Now we will also see and A-B test between the NA & boost. Sorry... What is the comp ratio?
 
Great job! Very interested in NA vs Boost! It will be a beast!!!! Hopefully see you a Drag week.
 
rumblefish360 said:
Awesome bro! Awesome!

Now we will also see and A-B test between the NA & boost. Sorry... What is the comp ratio?
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Thanks guys. The compression ratio is 9:1. Currently the procharger has a 10 lb pulley on it. I'm going to install an air to air intercooler so i'll probably loose a pound or two of boost. So call it 8 psi. Brian seemed to think that would be plenty to get me to 10 flat. We'll see. I just can't wait to drive it again.

Forgot to mention the transmission is a Cope Racing built 904. Billet drum, billet input and output shafts, rollers, all the good stuff! Also running a 5200 stall Ultimate Converter.
 
(This I think you know already, but I’ll just put it out there for those that don’t already know.)

You may loose a pound or two with the intercooler but you gain in cooler air which is more air than the heated air at a higher boost, so, that’s a win win!

With a 10 lbs. pulley, you’ll see that at the top end of the pull. Generally speaking a rising boost curve. (I think that’s cool.)
While on the way up the curve of boost, it is just like slowly adding cubic inches. At max boost, you will have added roughly 60% (or) more engine.

(Insert a Doctor Evil laugh here!)

That is already a healthy (N/A) Street engine.
 
Here's a dumb question. Put on my stock 318 single groove crank pulley last night and realized my alternator, water pump and crank pulleys didn't line up. Made me realize my old balancer was 1 inch thick and my new balancer is 1.5 inches thick. What do people usually do in this situation?
 
I have taken the replaced the Alternator sleeve spacers tubes. I went to the hardware store and picked up solid tubes suitable for replacement and cut them to size.

I haven’t had a big fan space issue yet. However, the same could be done. Some fans that are direct drive to the pulley have a spacernthat could be added on to or if you don’t have that early style solid spacer, you could get one and cut it down to size and install behind themoulley. If no spacer is available, the tube trick should work. You’ll just need longer attaching bolts. I used Long header bolts.
 
I figured out that I need a crank pulley for an internally balanced engine. One that would have come off a forged crank 340. The pulley I was trying is for external balance. Anyway, new pulley on it's way.

Just a few more items to check off the list and I should be able to fire this thing up. Still need to get a new driveshaft made.
 
Walker434 said:
I figured out that I need a crank pulley for an internally balanced engine. One that would have come off a forged crank 340. The pulley I was trying is for external balance. Anyway, new pulley on it's way.

Just a few more items to check off the list and I should be able to fire this thing up. Still need to get a new driveshaft made.
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Pulley alignment is a pain. I had to modify a hemi pulley spacer to get mine right with the crank trigger wheel.
 
Making progress. My Dad is building a 455 Olds for his 67 Cutlass. He was nice enough to loan me his Holley HP 950 to run on this thing while NA. Shouldn't be long now.

Dart 19.jpg
 
Okay, finally another update. Took the Dart to the track last night, these results are all motor.... N/A. Hardly had any time to tune on Dad's Holley 950 HP. Temp was in the 90's and Humid as all get out. 1/8 Mile track. Best pass was 7.51 @ 93 MPH. I know it's got a lot more in it with carb tuning and playing with timing but I was just looking for a shakedown pass before I install the procharger. Everything went well and nothing broke. Had a Blast. Now it's time to get serious.

Hopefully I'll be posting some 10 lb boost numbers soon! Been a busy summer and I've barely had any time to work on the Dart.
 
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