Cam choices for 400

[64Belvedere]

Ok, So I have my 64 Belvy with a 400 in it. It was rebuilt before I bought it with flat tops, crower cam, stock heads and a DP4B intake with an edelbrock performer 750 on it. A couple of years ago I put in a comp XE with 274/286, Lift .488/.491. It pulls pretty good but doesn't have the idle I want. I got spoiled with my 340 with the 274/474 purple shaft. I want more attitude with similar performace. Does anyone have experience with either of the following:

Comp Thumper 279/296, Lift .486/.473 107 degree centerline

Hughes Whiplash .518/.518 229°/242° 197 degree Center line.

Car gets street driven regularly, Not raced(yet) 2500 Stall 727 Stage 2 Shift kit, 3.55 sure grip. Car now has manifolds instead of headers. Headers were a headache.

 

[RustyRatRod]

Take a look at this one.

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=718&sb=2

It's Comp's version of the 484. It's also badass. Those are MOPAR specific lobes, not chebbie like most of the rest. It's also ground on 108, instead of Comp's usual 110.....not that there's anything wrong with 110. Also, the split pattern will lend itself well to mannyfolds.

 

[lewtot184]

does the 400 still have 8:1 pistons in it?

 

[RustyRatRod]

does the 400 still have 8:1 pistons in it?

meh....details details. He just said he wanted it to sound better. lol

 

[lewtot184]

meh....details details. He just said he wanted it to sound better. lol

o.k., i get it. how about a .690" roller?

 

[RustyRatRod]

o.k., i get it. how about a .690" roller?

Hell to the yeah, now we're talkin. lol

 

[64Belvedere]

Lol I thik a .690 is just what I want. It'll sound tough. I 'm not sure what the compression is. I know there is flat tops in it. That's why I was leaning toward the thumpr or the whiplash. It works pretty good wwith the current cam but I want more lump. It's only a stop gap engine until I build the 383 or 440 that are sitting in the Garage.

 

[RustyRatRod]

Chances are is has less than 8:1 then. I think those Hughes cams are probably better at getting good cylinder pressure from dismal compression ratios.

 

[64Belvedere]

I found some paperwork that came with the car. Seems to me it was 8.5 to one. I have the spec card for the crower that was in it when I bought it. It had a rower 280/460 with a 110 centerline in it. There is an old dyno sheet came with the car and cam specs when I got it. It says 409 ftlbs at 3900 RPM and 347 hp at 5100. I thought it might have the compression marked on it but it doesn't. Just the stroke, displacement and atmospheric cond. Anyway, Thanks for the advice.

 

[lewtot184]

low compression engines aren't real loper's. adding some compression will put some "pop" in it. i have a 440 with 9.3:1 in my '65 coronet with an engle k65 cam. its around 290+ on the seat and [email protected], .525 lift at the valve. you'd think it would have that cute root beer stand lope but it doesn't. of course i've done everything i can think of to get it to idle smooth. it just has that low compression rumble.

 

[RustyRatRod]

Trust the rusty one. Compression in that motor is more than likely in the 7s. Although rated at 8.2 or 8.5, because of Chryslers generous deck heights well above spec and their bigger than spec combustion chambers, real world blueprinted compression on the 400 was not even a true 8:1. Sorry to break it to you, but it's an unfortunate fact of life.

 

[lewtot184]

no problem a good 470 wouldn't cure. :blob1:

 

[RustyRatRod]

I hear that's a good kyoob motor to build.

 

[64Belvedere]

Don't worry dude, I'm not disappointed. I never liked the 400. Actually I am thinking of screwing together a 431 low deck with the 383 block I have in the garage. 440 source aluminum heads etc. I also have a good 440 with a fresh steel crank in stock here as well. Kinda leaning toward the 383 though. I always liked them. The 400 was never intended to be a long term engine. Just something to get use for now.

 

[RustyRatRod]

Send it to me when you yank it out. I want it.

 

[Meep-Meep]

Put a turbo on it.

 

[64Belvedere]

The thought of a turbo did run through my head. Hmmmmmm...I saw one somewhere on Craigslist yesterday......

 

[RustyRatRod]

I'd be a good roots blower motor, too. You'd want to limit boost, as the stock cast pistons would be the weak point...but as long as you didn't lean it out, it'd probably live.

 

[Meep-Meep]

There was a kit available for old Dodge motorhomes and those were low CR cast piston 440's. I'm sure you won't get enough boost to lift the heads but maybe 5 - 7 lbs would do wonders for that otherwise low compression slug. Put that together with EFI and make a great driver.

 

[IQ52]

Cylinder heads, cylinder heads, cylinder heads! If you think you can't have a bad to the bone idle with 7.3:1 compression, instant throttle response, and wicked acceleration, you need to go for a ride in the 454 we built for Don's Blazer.