Build thread- 73 duster, forged 5.7 w/ PS and AC, 5 spd, big brakes and floater rear

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AC pics for a member who PM'ed me about it because he needs the header clearance:

As you can see, I chopped some of the front cover off (chopped more off since then). I bolted the top back bolt to the block (had to open up the AC arm hole a bit), and braced the two front arms to front cover bolts. Only need to brace 3 of the 4 arms for a good install. Ends up close to the spool mount on mine- angled it out a bit and it was fine.

Sanden 7176 compressor.







 
Also- I've done a couple things with the car since the last post. I ran the Big Bend Open Road Race, where we finished 5th at 1.5 seconds off the target time for the 125 mph average. Car ran well, though we had some pump cavitation issues from about 10 miles out to the finish line.

After that I took the car on a 1200 mile road trip, and ran the three sisters texas highways run. Pretty drive, but roads weren't nearly as fun as an HPDE day. Still learning about the pump cavitation on this trip due to excessive heat and voltage.
 
Big Bend Open Road Race 2014 fly by

[ame]http://youtu.be/1e5FaF2uy9o[/ame]
 
Duster finished 4th out of 11 in the modified division of the hot lap challenge. Pics and videos below.

Duster vs new ZL1 camaro and C2 corvette grand sport replica (saturday 2nd session)
[ame]https://youtu.be/YREBMO_uhSk[/ame]

Duster vs modified 450 rwhp mustang GT on 305 pirelli R compounds. (saturday 3rd session)
[ame]https://youtu.be/8xIBdblDl0U[/ame]

Fastest laps of the weekend, 2:03.92 and 2:04.04: (sunday 2nd session)
[ame]http://youtu.be/2LZWvanMQQo[/ame]

[image]http://i1271.photobucket.com/albums/jj629/uhcoog1/4A9F1D03-985C-4712-A181-9A55C405AEA8_zpsrk5ph9tf.jpg[/image]

[image]http://i1271.photobucket.com/albums/jj629/uhcoog1/B78B117F-6B84-4CE3-B43C-997D73F22798_zpsnshi4lyv.jpg[/image]
 
Thanks bud. It's always fun to run with (or by) top of the line modern cars.

There was a gen 4 viper there with 600 rwhp in our group. He was faster than me (running 2:01's vs my 2:03-04). At one point I let him pass on the straight but kept my foot planted through the start/finish line (trying to make a time for the hot lap challenge). Anyway, it was interesting to see how slowly he overtook me. Guess this little 392 might have more power than I thought.
 
Uhcoog,
Looks like a blast. I didn't realize you have a 392 kit. Is it a 5.7 based (in other words, 4.05 or 4.08 stroke?). I was a little disappointed in the first video that the Corvette and the car ahead of him pulled away to the degree that they did on that big straight. I thought you had a 5.7 and was going to tell you it's time for a 392! :)
 
Ha- I blew up the 5.7 in 2013. Ran a bone stock 6.1 for a year. Now I've got a 6.1 based 392 (3.795 stroke x 4.055 bore). Should be 450 rwhp or so now, maybe a bit more once I tune it.

Yes- that little c2 vette is salty fast! I'm believe it weighs under 3,000 lb and he mentioned it has 600 hp or so. Also it's got 335 width r compounds in the back and he was able to roll on the throttle earlier than I could coming out of the esses.

At another point over the weekend I let a gen 4 viper pass. I didn't let up, and he pulled me, but it took some time for him to get past. He is running 600 rwhp. I'll look for that video.

My duster weighs 3,620 without me in it. Also, I shift from 4th to 5th about 120-125, and it drops to 4,000 rpm. Talk about lugging a gear! I have a .82 OD gear set on the shelf waiting to go in, just lack the time to drop the tranny.

The car will pull on my buddies 450 rwhp coyote mustang in 3rd and 4th. But it won't pull on anything in 5th.
 
Is yours the .68 or whatever 5th? That .82 will be sweet spot heaven Wade. My 5th is .75 and even it isn't great, by the time my BB started to get on top of it in 5th I was at about the 140 mark and things start to change then....
So im with you, when I can, im gonna do a .80 5th.
 
So maybe a little weight reduction program and a 6 speed? Is your car mainly a race car or a street car that you run on the track for fun?

My bro-in-law has a race car with a 650 horse small block chevy that he use to run up here in NorCal. Only about 2500 lbs. He could catch anything on the track in the straights, but it didn't handle or brake as well as the late model cars out there. He more recently bought one of the hot Corvettes (Z06 maybe?) supercharged LS7 I think. Anyway, he says his race car is faster, but his lap times are a LOT faster with the Vette because he can brake later and all the fancy stability control electronics help keep the car on the track better. Now his race car sits in the garage and he races the Vette. Geez, I could use a little of that extra cash. I'd buy a Drag Pak Challenger.

Anyway, looks like you're having a lot of fun out there. Just wondering if you plan to try to make it even faster. When is fast ever enough? lololol
 
Wade every waking moment has "what to make the Dustracer faster" going full time, 50% of the time. Congrats Wade on the 4th place against some serious new fangled tech. You should think about some 305's or 325/30/18 in the rear of that bad boy. Might help the tail happy end.
 
Car is dual purpose. It has AC, stereo, full interior, etc., and it's got a 4 pt removable roll bar, 5 pt harnesses, etc. I've been casually looking for a 'racecar' to take over track duties, mainly for increased safety gear. I'm unwilling to make the duster full track, as I want to be able to cruise with my son in the back one day (he's 8 mo old right now).

Oh yeah, I'm always trying to think of ways to make it go faster! I'm definitely approaching a point of diminishing returns, though. Things that would definitely help:
Drop 400 lb
Improve weight bias (currently 54.5/45.5)
.82 OD gear set (just need to put in)
Rear spoiler or wing, and extend the front splitter to match downforce
Fit larger wheels and tires (shoot- the Hoosiers I had were squeezed on the 9.5" wheels, which 'rolled in' the edges- lost about 1" of contact patch on EACH SIDE due to that! So really I was effectively running a 9" slick not an 11")

That's the 'list' I figure I would need to satisfy to make the car competitive at a USCA event. Not a cheap list; could probably buy a road race stock car for that!

Oh. USCA allows nitrous. So I could always spray the straights. That would be wild.
 
The .64 OD in the car is really just a cruise gear. It's a 2500 rpm drop (6500 down to 4000). The .82 is much better- 6500 to ~5300.

Also- I'll probably swap rear gears at some point.

The biggest issue is the track I've been running is shutting down for good in June. So there's no good reason to 'gear' the tranny and rear for that track- I probably won't get to run it again.

Big bend open road race is the end of this month. I'll be running the 135 mph average with 168 mph tech. I would prefer to swap the OD and rear gear by then, but I don't have time. So we'll be accelerating from 4,000 on up trying to get to 168 to help make that 135 mph average! The ideal would be a .82 with a 3.00 or 3.25 gear. It would allow a strong gear up to 150-160, and still have another gear to keep the RPM in the low 5,000's at the high end. Everyone needs a cruising gear at 160 mph, right?!
 
And I want 315's square. Hahahaha

Edit: 295/35/18 might be a better fit than a 315/30/18.


Current tread width with 265/40/18 super sports is 10.2", 26.3" tall (10.7 sec width). Tread width with 295/35/18 is 10.8, 26.1" tall (11.9 sec width). 275 and 285 don't add tread width over the 265 in super sports...

That's not much tread width gain...
The Hoosiers were 285/645/18, which is 10.9 tread width, 11.7 sec width, 25.5" tall.


Rival in 315/30/18 is 12" tread width with 25.5" height (12.6 sec width). 335/30/18 is 12.7" tread width and 25.9" tall (13.5 sec width).
 
LOL! Im in the same boat! I can get my front wheels widened and it costs the same to widen them 1/2" or 2" so my brain says "might as well make them 11" wide". I know this would require some frame "mods" at least to the rears of the front rails. 315's front 335's rear would make for a retarded amount of contact patch....
 
I do think there's a law of diminishing returns when it comes to tire width. The corvette guys on R compounds have found they are faster on 275's on some tracks, and 315's on others. You're only going to get so much contact patch area, so you either get it front to back or side to side. Obviously more contact patch side to side will help with absolute cornering, but my understanding is it may actually hurt front to back traction (at least in some instances past a certain point). Course, the corvette guys may have done better with less tire just due to less rolling resistance, etc, in an hp limited class...

And you don't HAVE to modify the front frame rail. Just don't turn that far! Lol
 
Just went through this thread for the first time, just wanted to say that you've done an awesome job on that duster so far! I'm also glad to see your out having a lot of fun with it!
 
How you been doing Wade, still driving your Duster? Did Alex ever get his on the road? I've been driving mine for awhile now, haven't gotten it on the track yet though. I have some suspension issues I need to iron out first.
 
PlumCrazyChris said:
How you been doing Wade, still driving your Duster? Did Alex ever get his on the road? I've been driving mine for awhile now, haven't gotten it on the track yet though. I have some suspension issues I need to iron out first.
Click to expand...

Not sure how much Wade is on here, but I believe his is out at a body shop, ultimately for paint job. Alex got his running and is working on some rust repair to help dial the whole car in a little more before it hits the road again.
 
Chris-
Mike has got it right- car is waiting its turn at paint. I spun three cam bearings on the duster in June of 2016, and I sent it to paint after that.

I'll be in Austin this weekend with the viper racecar at COTA. Come out if you have time. Parade laps at lunch all three days I believe. Give me a call or text tomorrow and I'll know more.
 
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