346ci FI vs 408ci FI
Originally Posted by eb02z06
My only reasoning for the small cube motor was torque-I don't need it. It's just gonna break more drivetrain parts that just cannot keep up. If it was a race car, then I would of built the stroker.
I want to say a couple things that, for some odd reason, don't seem to be common knowledge as they should.
1: More cubes=more power. I don't give a **** how high you spin anything, if you have identical builds the larger displacement motor will always make more power. If that wasn't true there wouldn't be c.i. limits in most class racing and we'd all be running 2 cylinder 40 c.i. motors spun to 30K RPM.
2: Cost. I just don't get it. An iron block is about $300 for a good one, and some searching will net you one for much less. Alot of FI guys buy aftermarket cranks anyway, so thats a wash. Stock stroke cranks cost the same as stroker cranks. You have to buy rods and pistons anyway. So even if you decided to use an aftermarket crank and iron block, you will spend $700-$1500 or so. I bought an Eagle crank for $500 I think, and paid $300 for my block. If $800 sounds like alot of money (especially for more power and a stronger foundation), you don't belong in the FI game. $800 is jack **** in the grand scheme of things.
Also, I sold my stock motor for much more than the block/crank combo cost me. I actually saved money by going 408, not to mention time. So unless you've destroyed your stock mill, sell that bitch and buy some bigger stuff. A good stock bottom end will sell for $1K easy.
Also, the 80 lbs over the nose is easily overcome by the additional power made by more cubes. The torque is nice too, and if you have any dilusions that your FI 346 is gonna hook any better than a FI 408, unless you have the shittiest build/tune ever on your 346, both engines are going to overpower any tire on the street.
1: More cubes=more power. I don't give a **** how high you spin anything, if you have identical builds the larger displacement motor will always make more power. If that wasn't true there wouldn't be c.i. limits in most class racing and we'd all be running 2 cylinder 40 c.i. motors spun to 30K RPM.
2: Cost. I just don't get it. An iron block is about $300 for a good one, and some searching will net you one for much less. Alot of FI guys buy aftermarket cranks anyway, so thats a wash. Stock stroke cranks cost the same as stroker cranks. You have to buy rods and pistons anyway. So even if you decided to use an aftermarket crank and iron block, you will spend $700-$1500 or so. I bought an Eagle crank for $500 I think, and paid $300 for my block. If $800 sounds like alot of money (especially for more power and a stronger foundation), you don't belong in the FI game. $800 is jack **** in the grand scheme of things.
Also, I sold my stock motor for much more than the block/crank combo cost me. I actually saved money by going 408, not to mention time. So unless you've destroyed your stock mill, sell that bitch and buy some bigger stuff. A good stock bottom end will sell for $1K easy.
Also, the 80 lbs over the nose is easily overcome by the additional power made by more cubes. The torque is nice too, and if you have any dilusions that your FI 346 is gonna hook any better than a FI 408, unless you have the shittiest build/tune ever on your 346, both engines are going to overpower any tire on the street.
Originally Posted by TS6
I want to say a couple things that, for some odd reason, don't seem to be common knowledge as they should.
1: More cubes=more power. I don't give a **** how high you spin anything, if you have identical builds the larger displacement motor will always make more power. If that wasn't true there wouldn't be c.i. limits in most class racing and we'd all be running 2 cylinder 40 c.i. motors spun to 30K RPM.
2: Cost. I just don't get it. An iron block is about $300 for a good one, and some searching will net you one for much less. Alot of FI guys buy aftermarket cranks anyway, so thats a wash. Stock stroke cranks cost the same as stroker cranks. You have to buy rods and pistons anyway. So even if you decided to use an aftermarket crank and iron block, you will spend $700-$1500 or so. I bought an Eagle crank for $500 I think, and paid $300 for my block. If $800 sounds like alot of money (especially for more power and a stronger foundation), you don't belong in the FI game. $800 is jack **** in the grand scheme of things.
Also, I sold my stock motor for much more than the block/crank combo cost me. I actually saved money by going 408, not to mention time. So unless you've destroyed your stock mill, sell that bitch and buy some bigger stuff. A good stock bottom end will sell for $1K easy.
Also, the 80 lbs over the nose is easily overcome by the additional power made by more cubes. The torque is nice too, and if you have any dilusions that your FI 346 is gonna hook any better than a FI 408, unless you have the shittiest build/tune ever on your 346, both engines are going to overpower any tire on the street.
1: More cubes=more power. I don't give a **** how high you spin anything, if you have identical builds the larger displacement motor will always make more power. If that wasn't true there wouldn't be c.i. limits in most class racing and we'd all be running 2 cylinder 40 c.i. motors spun to 30K RPM.
2: Cost. I just don't get it. An iron block is about $300 for a good one, and some searching will net you one for much less. Alot of FI guys buy aftermarket cranks anyway, so thats a wash. Stock stroke cranks cost the same as stroker cranks. You have to buy rods and pistons anyway. So even if you decided to use an aftermarket crank and iron block, you will spend $700-$1500 or so. I bought an Eagle crank for $500 I think, and paid $300 for my block. If $800 sounds like alot of money (especially for more power and a stronger foundation), you don't belong in the FI game. $800 is jack **** in the grand scheme of things.
Also, I sold my stock motor for much more than the block/crank combo cost me. I actually saved money by going 408, not to mention time. So unless you've destroyed your stock mill, sell that bitch and buy some bigger stuff. A good stock bottom end will sell for $1K easy.
Also, the 80 lbs over the nose is easily overcome by the additional power made by more cubes. The torque is nice too, and if you have any dilusions that your FI 346 is gonna hook any better than a FI 408, unless you have the shittiest build/tune ever on your 346, both engines are going to overpower any tire on the street.
So how fast has your turbo ls1 gone again?
BTW...my crank, rods, heads, block all together cost me $1200.
Originally Posted by LTLHOMER
I couldn't hook my car up as it was. Bigger is not always better. You won't regret going with the 346 but I think you will still break drivetrain parts because it will make plenty of power!
The peak, visceral moment of WOT 700 rwhp and high traction wrenching drivetrain parts into the point of breaking will happen as effectively whether from a 408 or a 346.
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Joined: Feb 2007
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From: Seattle area
There is something to be said for a progressive powerband its one reason why I wouldn't even consider a KB on my car. I don't have real traction now so more torque wouldn't help me alot way down low. You compared the cost difference on an iron block what does it end up being with an aluminum block?
Originally Posted by LTLHOMER
Are you saying with the same turbo, a bigger motor will make more power than a smaller one? I am new to the turbo game here so just trying to keep up...I mean since you know everything and all.
So how fast has your turbo ls1 gone again?
BTW...my crank, rods, heads, block all together cost me $1200.
So how fast has your turbo ls1 gone again?
BTW...my crank, rods, heads, block all together cost me $1200.
I don't have a turbo, I have a blower.
I also have yet to see anyone make more power than me with a D1SC on pure pump gas, and I did it through and A4, 12 bolt, and big MT's. Bob at EPP has matched me, but I have alot more room left if I wanted to push it harder.
I won't resort to being a smart ***, obviously you know better than I, but I didn't make this **** up. I listened to guys who do this **** for a living, and might know a thing or two about it.
Obviously a turbo sized for a 346 isn't going to make peak power on a 408, thats common sense. However, a turbo sized for a 408 WILL make more power on that 408 than a 346.
Does that make sense?
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Originally Posted by TS6
I don't have a turbo, I have a blower.
I also have yet to see anyone make more power than me with a D1SC on pure pump gas, and I did it through and A4, 12 bolt, and big MT's. Bob at EPP has matched me, but I have alot more room left if I wanted to push it harder.
I won't resort to being a smart ***, obviously you know better than I, but I didn't make this **** up. I listened to guys who do this **** for a living, and might know a thing or two about it.
Obviously a turbo sized for a 346 isn't going to make peak power on a 408, thats common sense. However, a turbo sized for a 408 WILL make more power on that 408 than a 346.
Does that make sense?
I also have yet to see anyone make more power than me with a D1SC on pure pump gas, and I did it through and A4, 12 bolt, and big MT's. Bob at EPP has matched me, but I have alot more room left if I wanted to push it harder.
I won't resort to being a smart ***, obviously you know better than I, but I didn't make this **** up. I listened to guys who do this **** for a living, and might know a thing or two about it.
Obviously a turbo sized for a 346 isn't going to make peak power on a 408, thats common sense. However, a turbo sized for a 408 WILL make more power on that 408 than a 346.
Does that make sense?
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Joined: Jun 2002
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From: Forced Induction Heaven
I have had two different types of turbo systems and a blower on my 346cid. I just rebuilt it because I found one of my bearings had excessive clearance. I could have built whatever size motor I wanted this time around, but I chose to stick with a 346cid...the highest I would go is a 364-370cid...which would be more like an all bore.
Top reasons I stuck with a 346cid.
More material in the block =s stronger and cooler.
no steep piston to rod angle
no extra fuel mods to accomodate larger cubes.
22 mpg...cruising and getting on it.
My setup is tuned around 91 octane and it puts down 590-610 rwhp (depending on which type dyno) on 9#s. But I also put down over 800/800 at the rear with no problems at all at 18#s...too (100/91 fuel mix).
I am not ******* larger cubes...as I think it is just a matter of preference....because you can always add more boost with smaller cubes. Now if you are talking NA....I would go with a 427cid...all day long.
Seen plenty of low 9 sec Turbo Karmann Ghias (italian design VW) and they didn't have 427cid...just little boosted 4 cylinder.
Top reasons I stuck with a 346cid.
More material in the block =s stronger and cooler.
no steep piston to rod angle
no extra fuel mods to accomodate larger cubes.
22 mpg...cruising and getting on it.
My setup is tuned around 91 octane and it puts down 590-610 rwhp (depending on which type dyno) on 9#s. But I also put down over 800/800 at the rear with no problems at all at 18#s...too (100/91 fuel mix).
I am not ******* larger cubes...as I think it is just a matter of preference....because you can always add more boost with smaller cubes. Now if you are talking NA....I would go with a 427cid...all day long.
Seen plenty of low 9 sec Turbo Karmann Ghias (italian design VW) and they didn't have 427cid...just little boosted 4 cylinder.
With FI, you want your pressure ratios close to 1:1 for a race fuel engine. If your looking for max hp on pump gas then the larger cube engine will work better, but suffer when on race fuel due to back pressure. Pressure ratio is the name of the game....people just still haven't figured that out yet.
Originally Posted by JZ 97 SS 1500
With FI, you want your pressure ratios close to 1:1 for a race fuel engine. If your looking for max hp on pump gas then the larger cube engine will work better, but suffer when on race fuel due to back pressure. Pressure ratio is the name of the game....people just still haven't figured that out yet.
Launching!
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look, a 408 setup correctly will outperform a 346 setup correctly any day, it is a matter of cfm... now if you dont use the correct size intake, turbos, headers, blowers, then that is a different story. but who on here doesnt do their homework before building a motor like the ones we are referencing? Bottom line is that i need to run 13psi on my 403 to make 800rwhp on pump (93) gas. how many of you can do that with a 346? not bashing your combo im just saying all things equal you need much more boost.
Jose I disagree with your statement...1:1 is 1:1 no matter what the cubes. You need the turbo to match but more cubes = more power with SUPPORTING components. There is a reason lynch went bigger cubes.....it aint for around the town off boost driveability
If you want to make big power you need big cubes, and big turbos/blowers.
Its way easier to start off with 1000hp n/a to get 2000hp
There are several factors to consider, not just cubic inches. Piston speed, rod angle, crankcase volume, detonation (smaller bore = less detonation), and cost vs power/torque/rpm goals.
The turbo or blower will dictate how much power it will make, if you do a killer solid roller 427 and put a P1SC on it then its not going to make the power of a 346 with an F1 on it. Its not even really an argument, it all has to do with money, available parts and being practical. If it all cost the same I'll take the bigger engine/turbo/blower, you would be foolish not to. But you are also limited by fuel, ignition, drivetrain parts etc. Just having a killer engine and huge turbo isnt going to get you very far unless you are just internet dyno racing without the other parts around it so thats why some (like myself) just run a 346. Not because I WANT to or think its better, because its good enough for what I want it to do and it was the cheapest and easiest way for me to go.
I know there are 4 cylinder cars making huge power and thats fine if thats what you have to work with, but if it costs just a little more to pick up 60 cubic inches and you can do it RELIABLY, why not
Its way easier to start off with 1000hp n/a to get 2000hp
There are several factors to consider, not just cubic inches. Piston speed, rod angle, crankcase volume, detonation (smaller bore = less detonation), and cost vs power/torque/rpm goals.
The turbo or blower will dictate how much power it will make, if you do a killer solid roller 427 and put a P1SC on it then its not going to make the power of a 346 with an F1 on it. Its not even really an argument, it all has to do with money, available parts and being practical. If it all cost the same I'll take the bigger engine/turbo/blower, you would be foolish not to. But you are also limited by fuel, ignition, drivetrain parts etc. Just having a killer engine and huge turbo isnt going to get you very far unless you are just internet dyno racing without the other parts around it so thats why some (like myself) just run a 346. Not because I WANT to or think its better, because its good enough for what I want it to do and it was the cheapest and easiest way for me to go.
I know there are 4 cylinder cars making huge power and thats fine if thats what you have to work with, but if it costs just a little more to pick up 60 cubic inches and you can do it RELIABLY, why not
Originally Posted by Forced370GTO
look, a 408 setup correctly will outperform a 346 setup correctly any day, it is a matter of cfm... now if you dont use the correct size intake, turbos, headers, blowers, then that is a different story. but who on here doesnt do their homework before building a motor like the ones we are referencing? Bottom line is that i need to run 13psi on my 403 to make 800rwhp on pump (93) gas. how many of you can do that with a 346? not bashing your combo im just saying all things equal you need much more boost.
Originally Posted by kp
If you want to make big power you need big cubes, and big turbos/blowers.
Its way easier to start off with 1000hp n/a to get 2000hp
There are several factors to consider, not just cubic inches. Piston speed, rod angle, crankcase volume, detonation (smaller bore = less detonation), and cost vs power/torque/rpm goals.
The turbo or blower will dictate how much power it will make, if you do a killer solid roller 427 and put a P1SC on it then its not going to make the power of a 346 with an F1 on it. Its not even really an argument, it all has to do with money, available parts and being practical. If it all cost the same I'll take the bigger engine/turbo/blower, you would be foolish not to. But you are also limited by fuel, ignition, drivetrain parts etc. Just having a killer engine and huge turbo isnt going to get you very far unless you are just internet dyno racing without the other parts around it so thats why some (like myself) just run a 346. Not because I WANT to or think its better, because its good enough for what I want it to do and it was the cheapest and easiest way for me to go.
I know there are 4 cylinder cars making huge power and thats fine if thats what you have to work with, but if it costs just a little more to pick up 60 cubic inches and you can do it RELIABLY, why not
Its way easier to start off with 1000hp n/a to get 2000hp
There are several factors to consider, not just cubic inches. Piston speed, rod angle, crankcase volume, detonation (smaller bore = less detonation), and cost vs power/torque/rpm goals.
The turbo or blower will dictate how much power it will make, if you do a killer solid roller 427 and put a P1SC on it then its not going to make the power of a 346 with an F1 on it. Its not even really an argument, it all has to do with money, available parts and being practical. If it all cost the same I'll take the bigger engine/turbo/blower, you would be foolish not to. But you are also limited by fuel, ignition, drivetrain parts etc. Just having a killer engine and huge turbo isnt going to get you very far unless you are just internet dyno racing without the other parts around it so thats why some (like myself) just run a 346. Not because I WANT to or think its better, because its good enough for what I want it to do and it was the cheapest and easiest way for me to go.
I know there are 4 cylinder cars making huge power and thats fine if thats what you have to work with, but if it costs just a little more to pick up 60 cubic inches and you can do it RELIABLY, why not
Originally Posted by germeezy1
What do you mean by twin turbo stock LS1?
Damn 161 at full weight,
Damn 161 at full weight,