I'm thinking about building a 408 for my duster. My question is are there anyone run low 11 on the motor and 9s on the spary? If so would you post your specs or what can I build to make this happen? Gear and converter as well.

That's very durable without spray especially if its strip only.

But would it be streetable?

You didn't say streetable but with what I see guys call streetable I don't see why not. My Son takes his 3200 pound Duster with a stock 360 crank out for street hits and it runs 10.20-10.30's NA.

A pump gas motor with ported rpm heads will run low 11s with ease.

Ok if I wanted a real simple 10 second street car and couldn’t port my heads this is what I would do with a 408

408 (10.5-10.8 comp)
Set of out of the box ProMaxx heads that have been checked out as I check everything out
Call Jim at Racer Brown and order one of his .520 lift solid cams
Port matched and plenum radiused Victor340 intake
MSD distributor
750-850 Holly carb
904 or 727 Transmission
4.10 gears
And as much convertor as you are willing to go with (yes high stalls are streetable) with a good cooler.
BP93 pump gas or equivalent
If that doesn’t get you in the low 11’s or 10’s with a 408 in a 3200 pound or lighter car something is wrong

All I'd do to the above is reduce gear to 3.70 . Put a plate from a reputable tuner (Pkre or inductionnsolutions or nitrous outlet) jet it for 175 range hp and HOLD on !
Converter wise I'd stay below 200 hp because you will be less likely to blow through the converter with the extra torque. Use a GOOD ignition and nitrous controller .
Gap rings accordingly.
Camshaft wise, keep it to what works on motor if only using a small hit

Honestly best thing would be to call PKRE and run the whole combination by him .

You are right but when you said it could be done on the motor it made me think. I have a low 9 car now but want something can drive on the street.

I'm thinking induction solutions..who is pkre?

Pkre is paul klycek. He is the guy that brought induction solutions into their present day tech level. He worked at induction solutions for a while then went back on his own.
Google it . He doesnt really do social media and isnt a big parts seller. Hes a tuner

Here is what I have: 62 Valiant, 8.50 cert cage, ladder bar, 9 inch w 3.89 spool, 29.5x11.5 tire, 3150 with driver.
904 trans with low gear set, Griner LBA Brake, hardened pump gears w/ wide lug, aftermarket input shaft, JW performance 8" Converter stalls 4800 on motor.
428" X block (4.070 X 4.125 Bloomer Performance Engineering kit) 11.0 to 1 compression, cometic head gaskets, Air Wolf 220 cfm CNC ported heads (standard/conventional port), Super Victor intake, 950 HP Holley carb, Crane gold 1.5 aluminum rockers, 269/275 @.050 duration .600.601 lift solid flat tappet Comp Cam on a 111 LSA. Springs are beehive. Headers are 1 7/8 to 1 3/4 step headers...fender well exit with 3 inch exhaust and pypes turbo mufflers.

The engine dynoed 615 @ 6600 with the shop's 1000 cfm HP 4150 Holley, peak torque was 547, but it was over 500 from 4200 to 6400.

Best numbers to date are 10.39-128 on motor, and 9.43-139 on spray. Typical numbers are in the 10.50's, and it'll run in the 9.60's on juice anywhere in the country, exhaust on or off.

What I've learned along the way after five years:
The stout, flat torque curve really shows off on the street, you can be at any speed, in any gear...stab it and it comes to life instantly, so much fun.
Street and strip, NA and Nitrous, are all compromises. The more you lean towards strip (high compression, deep gears, loose converter, more duration) the more it favors good NA numbers. The more you lean towards street (mild compression, gear, tight converter, more LSA) the more it favors a nitrous combination.

I'm only spraying about 150-160 HP. I'd love to spray more, but currently three problems prevent that. First, the 8 inch is on the limit of what it can handle. 2nd, the 3.89 gear limits what it will run on the big end, because both of those problems are made worse by the fact that the beehives are completely done at 7200. I think a change to a 3.73 gear, 9 inch vert, and better springs would allow me to up the nitrous a bit.

That is very posSible with spray. My buddies car runs like 10:30''s on motor and we spray it in the 8:20's on spray on 275 drag radials.

I would love to hear more about this one

Big block Chevy in a G Body with 2 kits. Can't say more. Grudge car.

LMAO ! ! I knew this was coming...LOL

You know this is a "small block" thread

This guy could never keep up in the small block or big block post. Those guys are way over my head but at least I was safe in this post. LMAO.

Spray is spray. It does not know if it is on a small block or big block. I have another buddy with a small block Chevy in a Camaro running in the 7's and he drives it on the street and power tours. Just depends on how hard you hit it.

Worst Statement About Nitrous Oxide Ever!

She's a cold hearted minx who will smile and reward you one minute, and destroy you and your engine the next! If you have ran a big block on the bottle for years, and switch to a small block and think you can treat it the same way...you're gonna be picking up parts with a five gallon bucket.

1970 Dart 3405 pounds with driver

408", ported x-heads, 9.5 to 1 dish pistons, 91 pump gas, 240/252@050 548"112 LSA solid cam, victor 340, Quickfuel 850, TTI headers, Carter strip pump mechanical, 5/16" line, stock fuel tank(keep it full)

727 Dynamic 91/2" converter

83/4 rear 4.10 sure grip , stock axles

28x9 MT pro bracket radial

Best 11.25@119

Wild Horse Pass Motorsports Park
Phoenix,AZ

I like this set up mild set up.