Help me Guess my E.T. ?

All,
Just about to fire up the new engine on a test run stand, car is painted, working on interior etc.
I’m kinda getting excited as I’ve owned my Demon since I was 15 years old (53 now)
Ran it back in the day with a low compression 360 and a .484 purple shaft cam to consistent 12.30’s - I’m learning every day that technology has come a long way.
I know track time will tell the truth, just wanted to get advice from all that are in the know and haven’t taken a 20 some year break from racing as I have.

Car is all steel with a fiberglass six pack scoop, stock glass/interior.
Front end is pretty much stock w/QA-1 90/10 shocks - front runner tires.
Rear end is 8 3/4, S/S springs moved in to frame rails, 4.30:1 gear, 275/60-15 Drag radial.
Engine is a .30 over 360 with a Rod Bloomer 4.125 crank/kit to equal 420 cubic inches.
Compression is near 10.5:1 with Hughes stage 2 ported eddy heads/Hughes roller rockers.
Bullett hydraulic roller cam .573 lift around 250 @50 duration. Eddy Super Victor intake with a Holley 750HP that flows 820.
Trans is a well built 904 with 2.76 low gear set, T/A manual valve body and a PTC 3800-4000 stall converter.
I usually run it at Great Lakes Dragaway, so typical Midwest sea level, temperature etc...

I think I’ve covered all of the variables??
I’m definitely looking forward to hearing thoughts/opinions on what this combination may run, but definitely looking forward to running this thing again.

Here’s a couple progress pics - everything seems to take so damn much longer since I’ve hit 50.......☹️

Thanks in advance!

Wally.

I would guess 10.70’s- 90’s assuming it sticks with the low gear and radial
Could definitely use more convertor, IMO.

Barring any high rpm valvetrain issues, and assuming all the support systems are operating properly(fuel sys, ign sys, trans, etc), should be easy 10’s.

Should make at least 550hp(STP), so losing 10% for correction and installation in the car, leaves you at 500.
500hp@3500lbs shows 10.78@123.

Wow. I didn’t expect that quick.
I didn’t put any type of roll bar in (yet)
I called Bullett and PTC with all the info they asked and both recommended around 4K Stall.
It’s all a baseline so if it needs more, I’ll find out when it hits the track.
Thank you guys very much, now I’m getting really excited!!

We did get it fired up on the test stand, I’ll try to post a video if possible??

Wally.

Forgot to ad some details, thanks for the reminder.
Aeromotive 11203 fuel pump, -8 line to the regulator, -6 to the carb.
MSD 6AL, MSD distributor and coil.
I’m thinking 6500 would be the limit? I’ll probably stay on the conservative side.

Thank you again!

Wally.

According to my calcs 500hp@3500lbs, 4.30 gear and 28" tyre?, your slip would look something like this on a good hit>

Power to Weight Ratio: 0.14 : 1 (HP per 1 Pound Weight)
60 Foot E.T. : 1.55
1/8 Mile E.T. : 7.03
1/8 Mile Trap Speed :96.68
1/4 Mile E.T. : 11.14
1/4 Mile Trap Speed :120
1/4 Mile Trap RPM :6,210rpm+slip
of course things vary on the day. and just to add another opinion

Thank you rb. Definitely appreciate everyone’s opinion.
Car hasn’t been on the track since the early 90’s.
Eyeing these numbers is inspiration to get my ass to working on it to get it done!

Nice looking car. Love a black car , but hot as fire at the track. With the stroke on your setup and if everything works at 100% I would say high 10.90s low 11.00 in the heat. Honestly I feel you may need to step up the carb to a 950 HP because a small block likes fuel..

Thanks Kindafast! It’s been black since I was a kid, so didn’t want to change but trust me, I thought about it!
I do have some friends with some carbs I can test with, I will be posting updates for sure.

You are quite welcome. Your setup sounds good . I have been running small blocks a long time myself. I messed with Eddie Heads for a long time but they are limited by the stock design no matter how much you port them. I picked up a set of Indy 360-1s from a from a member here and with some good port work they really helped my heavy car pick up. That converter you have is not enough stall in my opinion and it's good you can change carbs with friends. With a little trial and error that car will be a really good and fast ride. Love to show the big block guys what a small block can do..

My 1st 408 combo was,
10.3comp, .557 mopar cam, air gap intake, 750dp, Indy edelbrocks, stock....
727, 5,500 vert. 4.10 gear, 3250lbs. 10.70s@122+.
Zero to it, just tune and make the best of it. I see zero reason why it won't go the same as mine.
Will need a better verter change I'm sure to utilize its potential.
Hope that cam works good for you, my uncle currently has a similar hydro roller deal in the motor above and it sucks...
He hasn't worked at making the cam work tho so, parts wise, lightweight springs, valves, etc etc, its all done and sticking plungers at about 6,049 rpm

That's impressive #s right there. The weight had a lot to do with it I bet. Nice setup !!

Easily roll bar time.

In a way I'm happy, but not happy with myself for thinking ahead and doing it before it was painted.
Oh well, there's always next winter!!!

Should run Mid 10s but I agree it needs more converter, and lose the low first and 4:30 gear.

I would run a 4:10 with a 2:45 first in it to keep the SLR reasonable. You dont need it with that stroke.

Geez, Wally that thing looks killer!

Love the 904, I'll go against the grain here on the "more convertor" suggestions and say with 420 inches, a 4:30 rear end, and low first gear you need less convertor to hook up. Keeping the convertor you have, maybe consider 3.91's to keep that stroker rpm down at the big end and help from blowing the tires off at the start. I have to apologize, I have a bitter dislike for steep gears, mainly because modern Factory hot rods are running some unbelievable times with mid 3 rear end ratios.

I'm going to say 11.20 with traction issues and 10.80's in a perfect run.

Get it finished!

Converter is too tight. Need a good 8" that goes about 5 - 5.2K. A 10" that loose will be too inefficient.

That low gear will be quick, IF the track prep is there. When you get tired of spinning, put the 2.45 back in it. Rear gears sound about right for ~6500 in the lights.

Once it's sorted out - 10.80s in decent air @ 120.

You should be disappointed if it doesn't run fast enough to need a rollbar. You might as well get it done before you go to the track. Don't be like me and beat it mercifully for a few years(only running low 12s) and end up with a bent drivers door and torn up door striker. Racing whenever the track is open and lots of low 1.6 60fts were hard on my car with no cage and no frame connectors.

Looks like high 10's potential, especially with the 904.

These small blocks can move when setup properly. My 408 has stage II ported Edelbrocks by Ryan Johnson, 13:1 compression, solid flat tappet cam with 264/268 @0.05 with 0.621/0.632 lift, Victor intake, home built "750" e85 carb, 727, 8" converter (5k stall), 4.10 gear, 275/60/15 Hoosier drag radials, car is 3250#....Current best is 10.1 with old tires, hoping the new tires I just put on will help it nick the 10.0's this fall.

Badfish,
Thanks for the heads up - I was proactive somewhat when I had the car on the rotisserie and added the USCT frame connectors and moved the springs in to the frame.
If I were to start again, I would’ve added the roll bar and mini tubs.......hindsight 😖

I did learn how to post a video to YouTube. Below is the link, I hope it works.

https://m.youtube.com/watch?v=RtnO3F8nCak

Pretty close to my combo. But I am 390 ci. Stroked Magnum. All I can say is my max x heads are not ported and mine ran out of carb at the track when I ran a 750. I put an 850 on and it liked it a lot more. I am at 11.40s in a 69 Dart. I feel you should be high 10s.

Did you ever make it to the track? I am curious to see how the car actually did. I was guessing 10.90 myself, but figured the first few times out you would be in the low 11's.

You should be able to 60 foot in the 1.40s no problem.

Years ago when I ran a 408 stroker, I tested carbs. I don't remember the exact results but went from a 750 to 850 to 950HP and ran the fasted with the 950HP.

Nice car! It would love FI on it and then you can play around with data logging and really get a nice tune on it!

Finally made it to the track!
RB you we’re almost dead on!
Right off the trailer I was impressed but it definitely has more in it.
PTC converter flash stalls at just over 4000.
Gear is too tall, I lifted before the line, it was at 6500, didn’t want to push it.
Timing is at 14 initial, 36 total, running 93 pump gas.
I tell ya, what a blast.
Let me know your thoughts guys!
And thank you for all of the previous advice and help here!

Wally.

Congratulations Wally! Glad to see you finally got it out.

Congrats

Nice, here's what it could with those 60's at WOT to the traps>
60 Foot E.T. : 1.49 Seconds
1/8 Mile E.T. : 6.75 Seconds
1/8 Mile Trap Speed :100.70MPH
1/4 Mile E.T. : 10.70Seconds
1/4 Mile Trap Speed :123>125 MPH

I'm glad you got it out Wally! Congrats!

Nice runs and great pic!

Were you letting off early? (edit, nevermind, I see you did)

Thanks all!
I’m thinking of a 4:10, or if I wanted to be a bit conservative a 3:91.
My question is will it hurt the 60’ times much?
I know a few have said more carb, more converter but the car is so very streetable right now I’m not sure I want to change too much?
If it just touched the 10’s, you guys will probably hear me holler from Great Lakes Dragaway all the way to California!
Again, thanks everyone!

See if you can borrow a GoPro and capture rear tire slip (if any).

You may pick up by reducing starting line ratio if spinning now. Was the track typical for traction?
Plus you said you stopped short of the stripe. Not sure what impact that had on performance.

We got a guy here with almost the same set up as you, Demon,all steel +glass bonnet, street/strip car
SSsprings,3.91's, 10x28 Bias, Hughes 3500 verter, prob under 10:1?
Stock J heads 2.02/1.60
Mild 340/416, mild hyd. .474/495"
TR with 2 x 650DP's.
Shifts around 5600, traps around 6k.makes around 420fwhp
here's a shot of his best run, has been 1.55 60 at the same ET. Its very soft on the hit not like yours.



I would keep the gears and put a taller tyre on it, 4.10's would make around 200rpm difference in the traps, I would also at least try a bigger carb.
I went 1.8 10ths quicker on my hyd. cammed 340 street/strip Cuda with a sorted 850DP over the 750DP that it came with.
Just for a bit more info.