Forged 427 vs Forged 416

[C6Vette09]

I know the old adage that more cubes mean more horse, but in this day and age with all the technology out there, which size [forged 427 vs forged 416] would you do with a centri blower? :coolgleam:

 

[HLN A55]

would there really be that much a difference? Probably costs way more to go with a 427 to boot. I'd go 416 imho

 

[Manny@Dasilva]

I know the old adage that more cubes mean more horse, but in this day and age with all the technology out there, which size [forged 427 vs forged 416] would you do with a centri blower? :coolgleam:

Great question :

Here is my take on the matter :

The old rule applies " There is no replacemnet for displacement "

The bigger the better , like any other build bigger , better = more expensive .

I just finished doing a 383 forged build , only reason I did a 383 was that I wanted to keep my orginal block as its one the few items left that were orginal ............but if I was to do a build for an FI motor I would start with the LS3 as my base and build a 418 / Centri set-up

 

[dankhts]

you have something on Nasty 1 that's origional??

 

[Riley P]

Do blower motors work better with a longer or shorter stroke? Do blowers even care? I guess, as stated, it depends on your price range. (I like 427 as it goes back to the numbers of the big block days).

 

[Manny@Dasilva]

Do blower motors work better with a longer or shorter stroke? Do blowers even care? I guess, as stated, it depends on your price range. (I like 427 as it goes back to the numbers of the big block days).

Answer your question:

A "shorter" stroke will let you have a longer rod in the same block. By reducing the stroke, enlarging the bore and making the rods longer you benifit from a number of things. A larger bore means larger valves, less shrouding of the valves and more air flow and air flow is what is going to make hp and torque. Now there are limitations to the maximum length of the rod for any application. As the rod gets longer it has to move up into the piston further, which moves the pin further up into the ring pack. More air flow , lower compression = monster blower application

By lengthening the rods you have change the geometry of the rod angles in relation to the crank during the rotation of the crank. The longer rod is going to mean that the piston hangs around TDC longer making the combustion more effecient. This will mean more force on the rod/crank and more torque. Also since the combustion is more efficient it reduces detonation, which means you can run a higher compression ratio, which adds yet more hp/torque.

The one exception that I've read to all of this is a turbo/blower motor where it might be better to "not" have the piston dwell at TDC. Also blower motors make power way further down the piston stroke than a non-blown motor will as there is a lot more air/fuel burning and providing power.

 

[Riley P]

Question Manny,

The engine with the larger stroke will make more torque than the engine with a short stroke, correct? I believe this has to do with the distance from the connecting rod to the cranks axis of rotation. However, the engine with the larger stroke will not rev as high as it gains piston speed more quickly than a short stroke engine. Do I have my facts straight, or do I only have half the story?

 

[Manny@Dasilva]

Question Manny,

The engine with the larger stroke will make more torque than the engine with a short stroke, correct? I believe this has to do with the distance from the connecting rod to the cranks axis of rotation. However, the engine with the larger stroke will not rev as high as it gains piston speed more quickly than a short stroke engine. Do I have my facts straight, or do I only have half the story?

Thats right , the shorter stroke will rev much higher

 

[C6Vette09]

So, if i'm understanding this theory, then the smaller 416 may not be a bad choice as a blower motor?

Thats right , the shorter stroke will rev much higher

 

[Manny@Dasilva]

So, if i'm understanding this theory, then the smaller 416 may not be a bad choice as a blower motor?

That is correct

 

[C6Vette09]

Can a 416 be done with a LSX block?

 

[augiedog77]

Can a 416 be done with a LSX block?

I can PM the number of someone who can answer all these questions from experience. He's probably one of the most knowledgeable guys in North America when it comes to centris. He built a buddy of mines yellow vert and with a little 347 it made over 800 rwhp and he commutes from London to Toronto on a daily basis.
[mob][/mob]

 

[Manny@Dasilva]

Can a 416 be done with a LSX block?

Yes you can use the LSX block for the base.

 

[C6Vette09]

Thanks, Nasty98! Information is power and potentially, a whole lot of fun!

Yes you can use the LSX block for the base.

 

[HLN A55]

I can PM the number of someone who can answer all these questions from experience. He's probably one of the most knowledgeable guys in North America when it comes to centris. He built a buddy of mines yellow vert and with a little 347 it made over 800 rwhp and he commutes from London to Toronto on a daily basis.
[mob][/mob]

Actually I will re-word my post... It would seem that everyone that has already spoken in detail is talking from experience.

 

[not2melo]

^^^^^ I agree good one!
When spring time gets close the same people come out again.
LS3 FI would rock!