A little more HP out of my 400

[41indian]

Want to boost the HP on my 400 to maybe 300 to 350 without going into the bottom end, it only has 85000 on it

 

[41indian]

Will different heads and cam get me there. I plan on doing a coast to coast with it and don’t want anything to radical.

 

[Lefty71]

Yes, new aluminum or even old (915) worked over closed chamber heads and a proper cam with headers or HP cast iron manifolds should get you there, as long as your talking 4-bbl or add-on fuel injection. I would want to match up a good converter with cooler as well, if you don't mind getting a little dirty.

 

[HALIFAXHOPS]

Also put a performance cure in the distributor when you decide what you will do to suit it.

 

[yella71]

You can do it with the heads you have. headers and an intake for sure . a cam might help. its not as week of an engine as you might think. let it breath and you will see.

 

[RJRENTON]

Will different heads and cam get me there. I plan on doing a coast to coast with it and don’t want anything to radical.

Perhaps the best thing to do to insure long term reliability for your anticipated coast to coast journey is:
1. Tune up and safety inspection and tires
2, Coolant change check hoses
3. Change engine oil snd filter
4. Change trans oil
5. Enjoy the scenery

As the car has performed adequately thus far, do nothing else....no headers, cam, heads or other engine mods to cause you possible grief along the way.......just my opinion of course......
BOB RENTON

 

[R413]

Get rid of the 2.76 gears in the rear end. They will kill the torque on the little big block you have.

 

[pnora]

Want to boost the HP on my 400 to maybe 300 to 350 without going into the bottom end, it only has 85000 on it

What year 400?

 

[Outsider]

I get it, it's not that fun when your big block can barely turn a tire because it's smog era motor. 400s can be great motors, I bracket race a mostly stock one because I had it, and I'm happy. Are you willing to change heads, add headers and camshaft; it probably needs a new timing chain while you're in there. What is your budget, and how much work are willing to do, and is gas mileage important?

 

[RJRENTON]

Get rid of the 2.76 gears in the rear end. They will kill the torque on the little big block you have.

How about 4.10 gears......just right for a cross country road trip......???
BOB RENTON

 

[WileE]

No matter what year, the 400 does not have high compression. Which is ok, you can work with that. Get a set of aluminum heads with a smaller chamber size, port match an aluminum dual-plane intake, tune/jet the thermo-quad, recurve your distributor, a mild performance upgrade on the cam, headers and a 2 1/2" exhaust are a must. Don't go more than 3.23 gears if you're doing highway driving.

 

[Geoff 2]

You do not need new heads. How much do you want to spend?????

Best bang for the buck for a modest performance increase that you will feel is a new cam.
Something like an Isky 264 Mega. You have to be careful with low compression engines, over enthusiasm can turn them into dogs......real quick.

Have your old lifters re-faced to use with the new cam.....unless you want to risk wiping the new cam.

 

[Wietse]

Is one of these Whiplash cams not something suitable for this?
These are intended to use on the low compression engines without the need to change heads or compression ratio's.
Simple camshaft change with lifters (maybe springs also?) and a new timing chain.

Hughes Engines

 

[WileE]

You do not need new heads. How much do you want to spend?????

Best bang for the buck for a modest performance increase that you will feel is a new cam.
Something like an Isky 264 Mega. You have to be careful with low compression engines, over enthusiasm can turn them into dogs......real quick.

Have your old lifters re-faced to use with the new cam.....unless you want to risk wiping the new cam.

But is he going to get 300-350 with just that ?

 

[41indian]

Get rid of the 2.76 gears in the rear end. They will kill the torque on the little big block you have.

I wish 2.76, it has 2.43’s LOL

 

[41indian]

I wish 2.76, it has 2.43’s LOL

I have a 9 1/4 Shure Grip with 3.55’s for it, came out of a Magnum

 

[41indian]

What year 400?

It’s a 77

 

[pnora]

It’s a 77

Pretty low compression and the pistons are down in the holes.

 

[R413]

I wish 2.76, it has 2.43’s LOL

Those need to go first thing, immediately. Get a 2.9 or 3.2 and you will not believe how much different the car is with the same engine.

what size rear tires? Taller the worse in this case.

 

[RemCharger]

I wish 2.76, it has 2.43’s LOL

Had gears like that in my LeBaron.. you could pull first gear to 60 mph. Stock 360