Duster 11sec?

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F21

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Hello New guy
Finally going to put my 73 duster back together I took it apart 20 years ago looking for your thoughts from what I remember of the engine from 10 years ago it is a 340 30 over cannot remember compression ratio I believe it was in high 12 has a 590 solid cam B1 heads Crain 1.5 roller rockers Victor 340 intake tti step up headers
Should be just over 500 hp was going to rebuild the 727 with manual valve body Bolt in sprag 3500 stall maybe 4000
8 3/4 rear 742 center Auburn pro differential with 391 gear
26inch rear tire
I have ditched the front and rear impact bars from back of the
bumpers get rid of the HVAC and went to manual steering what do you guys think of the set up and will I see a low 11s
Thanks
 
Hey guys thanks I am a long ways from it going on the road shooting for spring I was also talking to Rick from A&A transmission about converter and rebuild kit I will keep you updated also thinking about starting A thread in restoration section
 
You may want a bit more gear. I run 4:10 gear with a 26.5” tire and cross the stripe at 6300-6400 rpm. You have less cubes, but a much better breathing combo.
 
Yeah I think you are right I may need more gear maybe 430 or 456 I think I will leave the 391 in and see how it goes
 
It’s been a long time got the car all back together and on the road ended up going with a PTC 4500 stall converter got 400 miles on it started to get on the throttle got The car On the scale today 3200 pounds with me in it have not loading up the converter and done a rip yet but have got on it and it feels only a 12.5 Second car
 
I have been wanting to get mine I the 12s. ALOT of Guys here recommended a " Tight" stall.. I'm NO expert, but make sure you're timing curve is on for Your mill. And 3:91s a great gear!. I'm running 4:10s... maybe 50 or 55 @ a comfortable rpm ( it's a street car, on the edge)
 
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Keep tuning on it. My 340 doesn't feel to strong unless I really let it go and get it into the upper rpm range. I bet that thing will want to go 7000 or more.
 
Are the heads ported? I don't recall what the B1 heads flow in stock form, but I seem to remember that it was not anything spectacular (probably about the same as stock Edelbrocks and such)...if that is the case, then I would only expect high to mid 11's at best. If you fully port those heads knock another second off that number.

Something to check, make sure you have the timing set correctly, this will make or break it (my car likes 34°). Also, don't baby it too long.....When I built my 408, I broke in the cam for 20 min, drove to the gas station (about 1 mile away), got fuel, drove home with a heavy foot and then went to the race track to beat on it....did this with my previous engines as well, no issues.
 
I can’t remember about the heads I want to say they have been ported and have 208 intake valves but not positive it’s been so long I will double check timing going to try and get to the track this weekend for the first time since the late 90s Will be disappointed if it only runs mid 12s what about shifting kind of nervous to over rev this thing have the rev limiter set at 6400 and seemed to still be pulling
 
I can’t remember about the heads I want to say they have been ported and have 208 intake valves but not positive it’s been so long I will double check timing going to try and get to the track this weekend for the first time since the late 90s Will be disappointed if it only runs mid 12s what about shifting kind of nervous to over rev this thing have the rev limiter set at 6400 and seemed to still be pulling
If you have the correct springs with that cam, and your bottom end is solid (i.e. good rod bolts, light forged pistons, etc.) I would not be afraid to send it to 7k if it were me...but if you are only comfortable with 6400 then that's fine too, it should still make good power.
 
I can’t remember about the heads I want to say they have been ported and have 208 intake valves but not positive it’s been so long I will double check timing going to try and get to the track this weekend for the first time since the late 90s Will be disappointed if it only runs mid 12s what about shifting kind of nervous to over rev this thing have the rev limiter set at 6400 and seemed to still be pulling
I see your location is Michigan. May I ask which track you will be going to, if you make it out this weekend?
 
Lapeer is not far from me. Check their schedule on Facebook or call them before driving there. I was there two weekends ago and asked about test and tune days. They said the schedule may be getting updates. I don’t have Facebook so I cannot check what is current.
 
Call down to Lapeer they will be open for a test and tune this Saturday

I would like to see 11.7/11.5
 
Are the heads ported? I don't recall what the B1 heads flow in stock form, but I seem to remember that it was not anything spectacular (probably about the same as stock Edelbrocks and such)...if that is the case, then I would only expect high to mid 11's at best. If you fully port those heads knock another second off that number.

Something to check, make sure you have the timing set correctly, this will make or break it (my car likes 34°). Also, don't baby it too long.....When I built my 408, I broke in the cam for 20 min, drove to the gas station (about 1 mile away), got fuel, drove home with a heavy foot and then went to the race track to beat on it....did this with my previous engines as well, no issues.

I was curious so...............
B1 BA.JPG
 
Great build but a couple of things stand out to me, one is a 391 is a great Street strip gear but by no means in my opinion going to bring out your best times. I would think of 430 would be a much better fit, second I turn my 340 to 6500 all the time and have for the last 15 years same build with your parts I would think 7000 would be a much better sweet spot.
 
you might be able to shift at 7k in 1st and 2nd gear but you will run out of race track before you hit 7k in high gear.....car needs more gearing and converter......stock stroke 340 going to need gearing and converter to get the job done
 
That “.590” cam will really like to turn some rpm. The heads should be ported at there maximum level possible to take advantage of that cam.
 
Yeah I think you are right I may need more gear maybe 430 or 456 I think I will leave the 391 in and see how it goes

with only a 26 inch tire, 3.91 is plenty of gear, but it will for sure like more convertor.
 
If you want your shift light to come on just before the finish line(will give you your best ET) then 391 is not even close. even if you were only shifting at 6000.
If your still driving it on the street. aka driving it to the track, then 410s and a street tire in the 28 inch range to get to the track.
If your trailering it. Then 430 456 would be much better.
 
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