Dad just built a new motor for his car and will be making runs soon, but curious to what you guys think it should run. I have my thoughts, but wanted to see what you guys thought.

Car is a 73 duster
3250 lbs with driver
Dana 60 with 4.56 gears
727 with ATI 8" 5000 stall convertor
30x11.5 slick

Engine
360 bored .030 over stroked to 408
11.6:1 compression (Scat rotating kit)
Intake - 340 Victor OOTB
Heads - Eldebrock 63cc heads non ported
Cam - Lunati .550/.571 lift 256/268 @ 50 dur
Doug 1 5/8" headers going into a 18" 3" pipe to a 12" 3" race muffler
Holley 750 carb

Low 11's. Maybe high 10's.

Yep^^.... those heads can hold up to around 500hp (250cfm), but are somewhat of a choke point on a 408, so assuming you have around 460 on track hp, and your chassis is ok, your ticket could look like this>

60 Foot E.T. : 1.55
1/8 Mile E.T. : 7.05
1/8 Mile Trap Speed : 96.38
1/4 Mile E.T. : 11.18
1/4 Mile Trap Speed : 120
1/4 Mile Trap RPM : 6,128+slip

When I had the 340 in my Dart it ran 11.60 @ 116 and 7.24 @ 94ish on pump 93 at 3460#. It was .030 over, 11.4-1, Curtis Boggs ported Edelbrocks, 236/242 @ .050, .586/592 hydraulic, X-Cellerator intake, QF Q-750, 9.5" converter that flashed 5000, 8 3/4 with 4.30 gears on 275 MT radials.


I'm thinking 11.50's for the OP.

11.35ish

You guys are all pretty much on point. Dad went to the track and ran 1/8th mile. Car worked well, but wasn't as fast as I thought. I'm thinking the heads are holding it back as stated, so be nice to try the new trick flow's down the road at some point.

rb446 - you almost nailed it.

60 Foot E.T. : 1.51
1/8 Mile E.T. : 7.04
1/8 Mile Trap Speed : 95

Should be low 11's. Dip into the high 10's when the weather improves.

Nice run, it'll get faster as you tune on it.

Yeah with a 1.51 60 it should look like this with good air>
60 Foot E.T. : 1.51
1/8 Mile E.T. : 6.87
1/8 Mile Trap Speed : 98.90
1/4 Mile E.T. : 10.89
1/4 Mile Trap Speed : 123
and thats 497fwhp, I'm sure with better TF heads it'll show.

11.10

Nice starting point. Now to find that little extra.

He has sounds like a good convertor, and the car has 4.56 gears. My guess is the front half looks better than the back half would have, especially with small headers and a stock head wifh a 4 inch arm.Very good 60 foot
Still, probably 11 flat or close.
Very nice job for first outing!!!!!
Before i invested in the trick flows, i would send the eddies out to Modern and have them CNC ported. They have an excellent program.
Easily another 50-70 horse laying on the table to take advantage of just by the head porting alone.

Let me fix this for you. Easily and I said easily 100-120 horsepower left in those heads and the intake needs work too

That is very true, either Modern or Pittsburgh can do an excellent 300cfm+ job on them if needed, no need to spend $2000 on TF's, then we would see some numbers, like mid 10's or better!!....and yes that is a good 60@1.51.

Thats true, potential is there to pick up that much power.
The reason i said more like 50-70 is because with his current combo, thats more likely reality.
The cam is relatively small with probably 540ish true net lift, and the headers are small too.
With a 1 7/8 header and bigger cam to take more advantage of the bigger head, your right.

And no need to sound cocky about it......” let me fix this for you” type stuff. What i said didnt need fixing

Thanks for the input guys. Will look into the cost of having the heads ported vs getting a set of the new TF whenever they come out. For now just going to fine tune it and run it until it needs freshened up and than make some tweaks to it than.

The one reason for the smaller cam is to keep the rpm's down. Shifting it at 6,000. Less RPM should let it live longer and less maintenance.

Man you have a bug up your azz lately. And it’s not all about cam lift as I’ve gone 9.80’s with a 520 lift. Carry on.

I never said it was all about cam lift.
With his current combo just putting ported heads on isn’t going to add 100-120 horsepower.
You attacked my statement as being untrue. It wasnt.
Sure, big roller, ported intake, bigger headers, more compression, etc, it’s going to pick up more.
No bug up my butt at all. Like you I have had a number of Eddie headed combos myself the last 20 years or so, including one currently.
What he has runs good.
Simply putting ported heads on what he has would probably pick the car up 3 tenths, maybe a hair more

Considering the current cam and small headers, plus unported heads, I have to ask, what would an Airgap , one inch spacer and 850 do for this combo? Or is the Victor intake close enough in runner size to not hurt power?

As its an easy swap for now, I would for sure try an 850/950DP if he could borrow one or has one, also try a 1" spacer as well, I think it could pick up 2/10ths, just like my little 340 did with stock heads from a 750>850DP....be interesting to see, could be even more?....think Mopar V8, think big carbs especially with 4.56/5000 stall and a victor intake, 750 is puny in my book with that set up....the larger hdrs/heads can come later...squeeze what you can first with what you have and easy bolt-ons/tuning, the chassis is already good....could shift it a tad more than 6k though I think with 256/268 @ 50 dur and see if it picks up mph which it should with the bigger carb.

IMO, with unported heads and the small headers, it won’t respond favorably to high shift points, but a lot of that depends on the motor and converter interaction.

I also feel like it would front half better than back half in its current configuration.

Easy enough to find the answer to both of those questions though...... try different shift points at a 1/4 mile track.