Newbie doing 454 swap need some guidance

[8008]

Hey guys. Got a 1987 454 out of RV that was a previous owners rebuild. Been machined and “rated 500 hsp” / comp thumpr cam/ roller rockers/ original 236 heads peanut ports / edelbrock performer / open chamber/ how legit is this? I’ve read a ton on these with weak heads that are great stump pullers but just trying to understand the flow of this - if I do anything here is there a way to reach 500 hsp without changing heads or cam? Is this cam ideal for low compression and why? Can I change inatake to larger ports or will that affect it all?

 

[nvrenuf]

Do you have a part number on the cam or the actual specs?

 

[fast 99]

Doubt 500 hp can be achieved with those heads. They are a low RPM design for torque. Need to make sure ports aren't larger in the intake than the head. They likely are. It's a HP killer.

A good set of aftermarket heads and matching valve train could get the HP desired even with low compression.

 

[Ricko1966]

The only way you are going to get significantly more power is better heads, and a better cam. I know that's not what you wanted to hear, but its the truth. A different manifold isn't going to do much for you. If I was going to just change one thing it would be the cam.

 

[8008]

Do you have a part number on the cam or the actual specs?

Yes.


CAM SPECS---INT EXH
ADV DUR: 283 303
DUR @ .050: 227 241
VALVE LIFT: 547 _ 530
LOBE SEP: 107.

 

[8008]

The only way you are going to get significantly more power is better heads, and a better cam. I know that's not what you wanted to hear, but its the truth. A different manifold isn't going to do much for you. If I was going to just change one thing it would be the cam.

Where I get lost is if I change heads, I need to change intake to match ports. And if I change heads do I change cam etc. changing cam - what I’ve read is this cam is designed for low compression. Would changing cam disrupt the pieces of this setup

 

[fast 99]

If available buy a complete upper kit. Heads, intake and cam matched to the application. Possibly Edlebrock, Trick Flow, or AFR makes one. Go directly the manufacturers consumer service line not a catalog or internet retailer.

 

[Ricko1966]

What is the intended use for this engine?

 

[Ricko1966]

If you just change the cam you can run your heads and intake. Call comp cam give them your details Ill bet there going to tell you an xe268 is good. But no matter what I don't think you are going to get 500hp with those heads. As for intakes you should run one that matches your heads. So if you have a peanut port manifold if you change to oval ports or rectangular ports you shoud change your manifold.

 

[8008]

What is the intended use for this engine?

Not drag but not a cruiser. Want some power not just torque

 

[8008]

If you just change the cam you can run your heads and intake. Call comp cam give them your details Ill bet there going to tell you an xe268 is good. But no matter what I don't think you are going to get 500hp with those heads. As for intakes you should run one that matches your heads. So if you have a peanut port manifold if you change to oval ports or rectangular ports you shoud change your manifold.

Ya I’ve stuck to that edelbrock dual plane that matches peanut ports. That’s why I’m debating on even changing heads bc everything changes then.

 

[Ricko1966]

Torque is what horsepower is based off of. Torque is what turns tires. Anything more than what you already have there is going to require a converter and gears. I wish I could explain this better. Hp is torque x rpm÷ 5252. A 400ft lbs engine that makes peak torque at 4000 example 400x4000÷5252= 305hp an engine with 200ft lbs at 4000 would be 200x4000÷5252=152hp that same 200 ft lb engine would have to spin 8000 to make 305hp your not going to get that bb to spin 8000 and that's just to make equal hp. Same engine but 500 ft lbs spun at 4000 would be 380. That big block isnt going to spin high, so you need to make torque to make hp.

 

[Mark Jones]

467 CU IN 9.3 Compression 236 headed ported peanut port engine, 228/238 @ .050 hyd roller cam, stamped steel rocker arms, Performer RPM intake, modified factory 4 quart oil pan. Dyno test below.

 

[bucket]

467 CU IN 9.3 Compression 236 headed ported peanut port engine, 228/238 @ .050 hyd roller cam, stamped steel rocker arms, Performer RPM intake, modified factory 4 quart oil pan. Dyno test below.

Frickin' awesome, as usual! But what kind of port work was done to the heads? Anything that could be achieved by a noobie that knows how to control a die grinder?

 

[Ricko1966]

Yes.


CAM SPECS---INT EXH
ADV DUR: 283 303
DUR @ .050: 227 241
VALVE LIFT: 547 _ 530
LOBE SEP: 107.

You need to get a cam card and put it up. The reason I said if I was going to change anything it would be the cam. The thumper series plays with valve overlap to get the all out drag car sound, but its not a full on cam. So you don't have any vacuum and you have a cam that sounds mean af when you could have a cam that's purpose is power not sound. Call Comp. Tell them what you have and what your goal is.