What will wake up a 400 engine?

[rumblefish360]

How do you fix this compression problem??
(Glad I have off this week, lol)

Mill the heads a lot of new pistons.

It’s definitely the way to know for sure, but under 10psi and it’s not a big issue, so why pull it down if you don’t have to? I have a low mileage 400 block in my shop now and it’s got .005 wear in the bores which roughly translates to .015” additional end gap. Add that to the factory end gap and it has more than my 4.500 bore twin turbo hemi...

Because it guarantees what is inside is sound.
For me personally, it is foolish not to. But I get some people like to gamble or just don’t care and will charge full ahead into the black. That’s fine for some but not myself anymore.

 

[BeatersRus]

all of these guys are right,and you see how it escalates??
see how fast you can go from a simple hopup to a full bore rebuild??
and then,youll have to upgrade everything Else too,to handle the power.
cooling,suspension,drivetrain...

if you want to drive the car,anytime Soon,
stick to the simple stuff,
hopup,and then maybe grab Another engine and slowly go thru that over time as the budget allows,
till youve accumulated everything to do a full swap.
just a suggestion.

the hopup alone will be over a grand,but at least youll be enjoying the car Quickly.
a full rebuild can start at 5k and go tharn,depending on what you want inside.
make a Good plan.

 

[RemCharger]

If that's the original motor to the car... what's the build date? There's a chance you have one of the legendary 230 blocks..
Also, yeah. Learn to tune a carb before doing the custom twin turbo route.

 

[barbee6043]

Hotrodding has always been about making the most power as cheap as you can. Anyone can take $$$$$$$$ and build grand engines or usually pay to have them built! Thats fine.
Sure some people have the unlimited income to buy all the cool stuff.
Some can afford the high $$$$$$stuff but get more thrills out of good ole fashion hotrodding!!!!!
And, if it ain't broke, why spend $$ to fix it? If broke fix it best you can, for as little as o can...unless you just like to spend $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

 

[TN Mopar]

It's. 72 Satellite with a 400. It does have a stockist 4bbl intake on it now ( someone must have put it on) and a rigged up Holly. It works but definitely needs a tune. Backfires and stuff. I was actually thinking about getting Snipper Fuel injection. I would think maybe that would solve a lot. I think that hooks up to the timing as well?

I am shocked that only one other person mentioned this
You have to fix the back firing before you do anything
The backfiring could very well be a symptom of why you think your engine wont run
it could be too lean or too rich
it could have jumped time
The distributor could be off

you can't upgrade a poor running engine if you don't understand why it is poor running to begin with
Go back to the basics
Learn to tune that engine
Those are skills that you will need with a stock engine all the way up to a highly modified engine
Basics are always the best skills to learn
you build on them as your package becomes more sophisticated

 

[rumblefish360]

@BeatersRus nailed it with make a plan and stick to it and do so with the KISS method. This is why I posted my ugly *** 400 in the Duster. Simple as a few bolt on parts. Mega under hood clearance with the Street Dominator, simple reliable TQ, basic cheap headers & exhaust, MP ignition upgrade, pretty much done there.

Your best get up and go factors will be a converter and gear change. Match them up with your upgrades and the package will make the car run.

 

[Curiousyellow71]

When I graduated high school we spun a bearing on our 440 and dropped in a 72 400 out of my grandparents fury ii. It never ran great even though it had 72k. What we had discovered is the timing chain had stretched. No matter what we did it ran the same, and slowly got worse. We had 3.23, 1 3/4 headers, thermoquad w iron intake. We later put in a used cam out of a 440 6 pack, edelbrock performer, 750 edelbrock carb and then stuck it in a 80 volare w 3.55s for my younger brother.. A new Timing chain made more of difference then anything else. He eventually spun a bearing...but lots of 6k burnouts.

 

[RemCharger]

The last 400 I pulled apart had 4 burnt exhaust valves. A compression rest wouldn't hurt.

 

[HALIFAXHOPS]

the rpm,is that the tall air gap one??
best to ask what will fit under your hood Before you buy.<<<<<<<<<<<<<<
yes,the street demon is a street carb and a performance carb.
i use them on small blocks and big blocks.

final thought,dont we have a distributor guru here,im not sure if he does the recurves tho ?? @HALIFAXHOPS

edit: i wouldnt throw your exhaust manifolds away either...
headers are a pita to work around,get installed,and Really heat up the whole engine bay,even if wrapped.
ive seen a lot of people very quietly switching back to stock/or stock honed/extruded.

Sure just need to know the modifications on the motor/trans

 

[Dodge Bros]

It's. 72 Satellite with a 400. It does have a stockist 4bbl intake on it now ( someone must have put it on) and a rigged up Holly. It works but definitely needs a tune. Backfires and stuff. I was actually thinking about getting Snipper Fuel injection. I would think maybe that would solve a lot. I think that hooks up to the timing as well?

Does the car still have points?? I think it should be electronic with a 400.

Have you changed the spark plugs?
Start simple, get it running good before you start bolting parts on it.

Our 72 400 that was born a 2 bb didn’t run that bad. Same car curiousyellow71 was referring too. I remember my brother pulling on to the highway not quite straight yet, going full throttle and the sure grip unloaded the tires, spinning the tires for about 100 feet, well into second gear, getting out of shape, and ending up in a corn feild. Will your car do that yet? It is the same basic combo other than our car had 3.23s and headers. I am guessing it was a mid 15s second car. I recall right after we put the engine in, it broke an engine mount, yanked the the cable holder out of the bracket, and sucked the pedal to the floor until I shifted into second gear. Was no 440, but we had a blast with it.

 

[64fury74charger]

You can get off track easy trying to get an unknown motor to run decent. As others have said start with the condition of your current motor. Timing chain is top of that list because nothing else will be right unless the chain is tight. Big block mopars are hard on timing components.

Pop distributor cap and move the crank and see how much the crank moves before the distributor rotor moves. Another good thing is to verify your tdc in case the chain may have been replaced by a chebby shop and not lined up properly.
I have always liked knowing what I am running on.

 

[joemish]

What HP gains would I get with just a Holly 4bbl, intake and headers?

Really need to wake this thing up! I think I read that the heads on the 400 is what really holds it back?

Thanks!

93 octane

 

[joemish]

What HP gains would I get with just a Holly 4bbl, intake and headers?

Really need to wake this thing up! I think I read that the heads on the 400 is what really holds it back?

Thanks!

If your not competing on a track leave it alone. If it's not broke don't phuk with it.

 

[Mr. Mike]

As others have said, timing chain, new 650 cfm carb with unworn throttle shafts, aluminum DP intake. Check hood clearance as Mopar cast iron intakes on B/RB blocks were no rise. Axle gears next. Save the headers for last.

 

[kbfallon]

What HP gains would I get with just a Holly 4bbl, intake and headers?

Really need to wake this thing up! I think I read that the heads on the 400 is what really holds it back?

Thanks!

From a lot of past experience....Do a Good Tune-up on it, check timing chain slop, and a compression test or better yet a Leak Down to see what over-all condition it's in. Most big-blocks respond favorably with a set of the correct size hedders and free flowing exhaust. Also a re-curve on the distributor and set up the carb you already have. Get it running right and enjoy it for what it is.

 

[JG71B]

I did this last summer with a bone stock 78 400 4bbl motor with 57k miles. 100% untouched with original trans for $600. Had the original nylon timing chain even. Changed that out with a good Cloyes double roller, straight up just as the factory one was. An Edelbrock Performer intake. Edelbrock 1406 600 and a new set of Heddman 1 7/8 headers I blasted and painted with VHT header paint. Stock timing was 2 1/2* btdc. Still using the original distributor,

I bumped it to 15*. RJ12YC plugs. Stock ignition with an old orange box. For what it is, this thing fries the tires and just keeps pulling and pulling until I let up. 3.23's in the rear also and it screams on the freeway also. I run straight 90 octane gas without the bs additives. Doesn't take much to wake them up. Just start with what the current condition is remembering to stick to the basics and start with the basics. I planned on putting a cam and aluminum heads on this thing. I'm not running it (there will be an occasional 1/4 mile pass once twice in the coming summer) mostly cruising and everyday driving. But at this point, it's staying as is and I'll drive the **** out of it and build on another one. It runs way too good to touch it any further. Don't expect too much. Be realistic about what you have and you'll be happy. Everyone that's been in the car has been quite surprised at how it runs for what it is. Here is how it currently sits (don't mind the pie tin, it's what the AC came with)

 

[Myasylum]

Yea, I think I'm going to see how good I can get it to run bone stock first. If I get anything I want to get a 8 3/4 rear nothing lower then 3.73 gears with a sure grip. If I can find one?