Which Displacement would be better?

[C@mero]

I have my D1x ordered and I’m going to build a new long block. Want to be at the 1000whp mark. Contemplating on either staying stock cubes or go bigger.

My question is… If ALL things are equal (CR/boost/fuel etc etc), which engine would net more power? Fully forged 376 or fully forged 408/416?

Track car only. Maybe some weekend fun runs.

[ttshovel]

Originally Posted by C@mero

I have my D1x ordered and I’m going to build a new long block. Want to be at the 1000whp mark. Contemplating on either staying stock cubes or go bigger.

My question is… If ALL things are equal (CR/boost/fuel etc etc), which engine would net more power? Fully forged 376 or fully forged 408/416?

Track car only. Maybe some weekend fun runs.

Cubic inches is power, all else being equal. But I will say that for a longevity standpoint I'd stick with a stock to 3.75 stroke to keep a better compression height.

Don't be afraid of compression, and run e85 if possible. That's the only 2 other things I've got for you

[Greenhornet2]

more cubes make more power as long as you have the supporting mods to supply it. You will need to upgrade your cooling system though.

[C@mero]

It’ll be on Flex for sure. Got the Fore ordered and ID 1700s. I was thinking around 10.5:1. Not planning on going too crazy with boost. Maybe around 15lbs.

[C@mero]

Originally Posted by Greenhornet2

more cubes make more power as long as you have the supporting mods to supply it. You will need to upgrade your cooling system though.

I have 1 7/8 LTs right now, maybe bump up to 2”. I’ll have the obvious cam/heads (Frankenstein).

Cooling as far as radiator upgrade? OR better intercooler?

[Greenhornet2]

Originally Posted by C@mero

I have 1 7/8 LTs right now, maybe bump up to 2”. I’ll have the obvious cam/heads (Frankenstein).

Cooling as far as radiator upgrade? OR better intercooler?

Radiator at least maybe different fan setup. I'm not sure what everyone is running but have read that the bigger CI the stock system can't maintain temps. 1 7/8th headers aren't much of a restriction until I believe around 800whp. That is not to say you wouldn't still benefit from them if you are lower than that. Even I would see some gain with 2" but it breathes fine where I'm at.

[ttshovel]

For what it's worth I've always ran a half sized radiator when I was on e85 and now on m1. Cooling temps were perfectly fine.

[C@mero]

Originally Posted by Greenhornet2

Radiator at least maybe different fan setup. I'm not sure what everyone is running but have read that the bigger CI the stock system can't maintain temps. 1 7/8th headers aren't much of a restriction until I believe around 800whp. That is not to say you wouldn't still benefit from them if you are lower than that. Even I would see some gain with 2" but it breathes fine where I'm at.

Definitely something to consider since the engine will be out of the car anyway.

Originally Posted by ttshovel

For what it's worth I've always ran a half sized radiator when I was on e85 and now on m1. Cooling temps were perfectly fine.

Do you drive the car on the street, or strictly track? Your 1/2 size is maybe more efficient… maybe?

[SSE 4 2SS]

Originally Posted by C@mero

Do you drive the car on the street, or strictly track? Your 1/2 size is maybe more efficient… maybe?

I run a 417 cubic inch motor at 10.5/1 compression on C-16. With a half filled block, and a dual pass radiator, I run cooler temps than stock by a substantial amount…

Coolant temps at the end of a one mile WOT pass are in the 190 degree range max depending on ambient temps….

Yes I drive it on the street…. Though it isn’t a blower car…

While the old adage there’s no replacement for displacement, don’t forget to consider rpms….

Build a long block for higher rpms….

[eLeSthree]

Originally Posted by ttshovel

For what it's worth I've always ran a half sized radiator when I was on e85 and now on m1. Cooling temps were perfectly fine.

I was about to say, I live in FL and never had an issue with the stock radiator on an iron 427. I upgraded to a $167 ebay radiator (physically broke the plastic one) and my temps are solid 196-201 stock fans, stock thermo, modified tune.

[C@mero]

When I meant track, I meant drag strip. No road course near me.

Any recommendations that won’t break the bank, or would the oem suffice? When I do drive on the street, it’s mostly highways.

Originally Posted by SSE 4 2SS

I run a 417 cubic inch motor at 10.5/1 compression on C-16. With a half filled block, and a dual pass radiator, I run cooler temps than stock by a substantial amount…

Coolant temps at the end of a one mile WOT pass are in the 190 degree range max depending on ambient temps….

Yes I drive it on the street…. Though it isn’t a blower car…

While the old adage there’s no replacement for displacement, don’t forget to consider rpms….

Build a long block for higher rpms….

I was thinking of going up to 6800rpms

Originally Posted by eLeSthree

I was about to say, I live in FL and never had an issue with the stock radiator on an iron 427. I upgraded to a $167 ebay radiator (physically broke the plastic one) and my temps are solid 196-201 stock fans, stock thermo, modified tune.

Saw your old comment with the fan

“ Exactly what I was going to say. Adjusting the tune to make the fans run at %50 power under 192 degrees, then %70 up to 196, then %91+ made a bigger difference than upgrading my radiator.”

[ttshovel]

When I ran it on e85 I street drove the car. Iron, 3/4 filled block and a cheap dual pass, 22" wide griffin with a spal fan. Nothing exotic. Stock water pump and accessories to boot

[Greenhornet2]

Ok, maybe i'm wrong then. I did read a thread of an over 400 CI person having an overheating issue and everyone chimed in with what they did to combat the issue. Most was new radiator. I can probably find the thread. Now I Don't know exactly what his setup was, or if he was running E85.

[RealQuick]

Anyone else think a D1X is a little small for the bigger cubed motors? Especially if you want 1000rwhp @ 15psi.