Posted By: earthmover
my 400 street motor - 02/12/13 01:14 AM
well working on the 400 like to see what you guys think of the build and how you think it will run..
stock stroke,rods,and pistons...cran cam hyd. 504/528 cut on 112 going in at 106...tm6 intake clean and matched, with 950 hp carb...heads are 906 little port work, factory oil pan cut and made to a deep pan, going to install baffels..also going to add no more then 150 shot of nos...727 , 3000 verta ,456 gears with ss duster ,70 duster ....so what do you guys think it will do ???? pistons are 70th in the holes, will have headers....
here is a link to the build as it is being done..
http://www.forabodiesonly.com/mopar/showthread.php?t=205404
Posted By: WO23Coronet
Re: my 400 street motor - 02/12/13 02:20 AM
Sounds like a stout build on the cheap! WAG on performance, high 11's on motor, high 10's on spray? Apparently the stock cast pistons can take quite abit of SAB ($h/t and abuse). When do you think you'll be able to run it?
Posted By: earthmover
Re: my 400 street motor - 02/12/13 02:27 AM
Posted By: Mr.Yuck
Re: my 400 street motor - 02/12/13 03:04 PM
The big problem i see is compression. At best it will be 8:1. I don't see high 11's maybe high 12's with the light car and steap gears. then drop a second for the gazzzz. If you can cut the heads a tad you might be able to get 8.5:1. I'd sell the bottle and get ya some boost. That will fix that 8:1 issue.
Posted By: JohnRR
Re: my 400 street motor - 02/12/13 03:29 PM
Some of you guys are not being POSITIVE ....
Posted By: FastmOp
Re: my 400 street motor - 02/12/13 03:43 PM
I have friends that built about the same combo just with a .590 cam and there always low 7's in the 1/8 on motor and hi 6's on a 175 shot. Your car is lighter then there's so I think your going to be ok.
Posted By: Mopar-Al
Re: my 400 street motor - 02/12/13 03:49 PM
I didnt go to the abody link, so what all have you done to the car? Carb seems a little steep, but it may suprise a few around here. Gotta get it to hook, then ride it out. If your around 3200 lbs and can manage 375 hp high 11's is doable off the juice around 111/112 mph.
Posted By: moparmafia
Re: my 400 street motor - 02/12/13 04:54 PM
My 70 roadrunner complete car with bench seat and air grabber hood went 8.20 in the 1/8 mile with a stock 400 shortblock with 120k miles on it. It had 906 heads with fresh valvejob and had been cut .030. The cam was an old erson .471 lift. I had a coan 4000 converter and 3.23 gears and wore out pep boy radials.I always wondered what the thing would run freshened up with some compression.
Posted By: WO23Coronet
Re: my 400 street motor - 02/12/13 06:28 PM
Seems like a decent combo to me, the only thing that doesn't fit is the "doggy" compression. Single plane, high stall, 4.56's, 3200 lbs, ported heads…I bet it will be suprisingley quick.
He has a similar combo to the Mopar Performance Duster that was used to test the MP cams years back, and it was in the 11's.
I still think the car will touch high 11's if the chassis is set up right and everything is just so. It also could be a high 12 car if the chassis is out of whack
https://board.moparts.org/ubbthreads/show...e=1#Post7538803
Posted By: dogdays
Re: my 400 street motor - 02/12/13 06:49 PM
I think it'll be pretty good, I like the advanced cam. Any extra work in the heads will help, too.
IIRC the "950HP" carb flows in the 750 range, Holley didn't name it for its airflow. It'll be fine and worth some power.
R.
he's savin' a lot of money... this is not an expensive build.
meanwhile, the guy building the gen iii swap... lol
my input is if they can shave the heads down a bit and get the comp to 9:1 this things gonna run like a skeert deer, & get him down the track in the 11's without a problem, not even using the bottle. depending on the rest of the chassis he might even get in the 10's with his 150hp shot.
Posted By: earthmover
Re: my 400 street motor - 02/13/13 12:53 AM
well thanks for the love those of you that see the big point lo buck build.
.and those that don't that's fine to.
. there is always that group..
.so here goes...the heads will be cut once they are in the shop,but have to check things before I just go cut them..the idea behind this is to have a car I can get back in and just drive if I want or have a little fun with when I need...not a lot of cash for this build as I am trying to get my chassis car going here soon...lot stuff to learn on that car..
...this is my old small block car that I have had for about 16/17 yrs now and just want to drive it or something again for those hard days at work and need to vent...lolso I don't plan to sit the world on fire by no means just go out to the store or town and the woods
if needed..lol
You have to remember.................there were lots of factory lo-compression motors that got MP cam stuffed into them, a single-plane HSD or TM6/7, headers, a holley and then they ran hard on the street or strip. How else did the wedge motors build any street credibility since even the 69-71 motors with 906's weren't as rated from the factory either.
The biggest booger in the soup is the really soft low-end torque from the lack of compression. High stall and lots of initial mech. advance will help.
Posted By: earthmover
Re: my 400 street motor - 02/13/13 01:45 AM
Posted By: gch
Re: my 400 street motor - 02/13/13 01:59 AM
The advance will help the idle and I would say low end but with a converter and steep gears low end is really upper mid range lol.
Bolt it together,sort out the tune and have a ball with it.If nothing else it will relieve stress.
Posted By: Winchester 73
Re: my 400 street motor - 02/13/13 04:42 AM
before you spend money to cut the heads for compression you should read this:
http://www3.sympatico.ca/big-d/460.htmthis guy made a 460 inch motor by grinding down a CAST crank to 400 mains and ofset grinding the rod journals.motor was built for 1500 bones and ran tens for years in a 3400 lb mirada.do the math
400 stroke =3.38
440 stroke =3.75
pistons move up .37 with a (free?)cast crank,how far are your pistons down?how much quench right now to the flat side of the chamber?
Posted By: cudadoug
Re: my 400 street motor - 02/13/13 07:21 PM
I had to dust off some notes to be sure, but here's a real world 400/72 Duster that I had in the 80's. OE 318 car, manual steering and brakes, weighed 3,384# with me and 3/4 tank.
OE 400 pistons were -.058 (average of 8 holes) down. Replacement rings and subbed a 383 steel crank. Why we did the steel crank I'll never know except that we "thought" the cast crank was junk. All we did was add weight, as the cast crank is lighter. DUH...
452 heads, ported to MP templates, 3 angle VJ.
MP .509 cam, TM-6, 750 DP
Hooker 1 7/8 Fenderwell headers (HATED those things!)
Stock 727 w/MVB, 10" B&M Holeshot (LOL!) converter, 3.91's 27" tall G60 Dunlop Qualifiers, with OE Ralley wheels.
BONE stock car, all steel, full interior, full exhaust to the bumper went low 13.80's @ 102
We made it go 13.61 @ 104 best by flipping spring hangers, subframe connectors, recurved dist, jetting, timimg, turn downs for the muffs at the rear end, etc.
Advanced the cam 6*...BOOM! 13.45 @ 106! Jetting changes resulted in a 13.38 @ 108 best.
Added a glass 6 bbl hood: 13.31 @ 108
Sealed the scoop: 12.90 @ 109
More jet/squirter changes: 12.78 @ 111
Still on Dunlop's and through full 2 1/2" exhaust.
I was accused many, many times of having a hidden bottle, or a low deck stroker. No one (ESPECIALLY Mopar guys) would believe that this smog motor could run with (and in many cases better than) their 440's!
We all know light wheels are a gain, right? I replaced the OE rallies with Centerlines. 15x7 rear on the same Dunlops and 15x3.5 fronts with a VW tire: 12.61 @ 113. And I'm driving it to work every day, rain or shine.
The car went on get a 440, blah, blah and eventually went 10.70's, but I digress. I had more fun with that 400 than I've had with many, faster Mopes!
Posted By: CH3NO2
Re: my 400 street motor - 02/13/13 07:55 PM
Here's something positive for you to consider. That build would be perfect for a small procharger. Just make sure you check valve to piston clearance and install that cam @ 112. 6 to 8 lbs of boost will wake it up with what you already have. Forget the No2, it'll melt your pistons if you don't "tune" it just right, just a thought, Steve
Blame my lady friend , she is always riding me for not looking at the world thru rose colored glasses 
