slider
1/2 ton status
Dude grow a set and punch it. There is no thing as too much power.
CK5
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Holy $hit.....Too much HP
- Thread starter NITRO
- Start date
NITRO
1/2 ton status
haha...i know. it just kinda impressed the hell outta me i guess. i was used to the 350 and that thing just blew the 350 outta the water. now i have a chance to get a $14000 1 ton truck for $7000 but the only catch is is that i hafta sell the 79 K5. i dont know if im ready to do that....ill have jon put up a pic of it for me. it is a show truck and i dont know what to do...
NITRO
NITRO
I was standing on the drivers side as he left the other night, and the drivers side tire definitely left the ground as he launched. We were all in awe... /forums/images/graemlins/thumb.gif That thing is bad a$$ and now he wants to add nitrous!!! /forums/images/graemlins/eek.gif He's planning to run it at Bandimere on June 6th. That's "Truck Day" at the strip. /forums/images/graemlins/cool.gif
NITRO
1/2 ton status
looks like ill b keepin the beast. im gonna try to get a job so i can get the other truck that i want. i got my exhaust made for it today. 2 1/2" aluminum all the way out back straight true duals. ill get it on tomorrow and see how she sounds. Now i can finally hit full throttle and keep my hearing....what a plus
NITRO
NITRO
Hossbaby50
3/4 ton status
That truck is sick. I can't imagine that much power in my truck. I knew his motor was strong, but to lift the tires of a truck that damn big and heavy is a miracle. The miracle of big block power. Shawn is sick. That truck would outrun most cars, and he wants nitrous. /forums/images/graemlins/crazy.gif
bryguy00b
3/4 ton status
what does CFM stand for again? and so is it the bigger cfm carb you have...the better milage you get ur what...im a little confused.. /forums/images/graemlins/confused.gif
Z3PR
Banned
Cubic feet per minut
bryguy00b
3/4 ton status
ok...so why would you get worse gas milage with a lower CFM carb verses a higher one?
jhrody
1/2 ton status
[ QUOTE ]
ok...so why would you get worse gas milage with a lower CFM carb verses a higher one?
[/ QUOTE ]
I think it has to do with less pedal depression is necessary with a larger carb. You get more air in while not having to squeeze that accelerator pump as much...if you can understand what I'm saying. /forums/images/graemlins/blush.gif
Much in the same way that more cubic inches, might help your gas mileage in some circumstances--- less pedal application gets the same amount of work done with more pedal application with less CID. I'd swear my 454 Jimmy get's damn near the same MPG as my old 250 Blazer.
ok...so why would you get worse gas milage with a lower CFM carb verses a higher one?
[/ QUOTE ]
I think it has to do with less pedal depression is necessary with a larger carb. You get more air in while not having to squeeze that accelerator pump as much...if you can understand what I'm saying. /forums/images/graemlins/blush.gif
Much in the same way that more cubic inches, might help your gas mileage in some circumstances--- less pedal application gets the same amount of work done with more pedal application with less CID. I'd swear my 454 Jimmy get's damn near the same MPG as my old 250 Blazer.
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Something everyone that thinks about dropping a BB in there truck should consider:
When you drop a high HP motor in your truck the hp will find the weakest link. If you have a TH350 the BB will eat it for lunch.
A Th400 that is well built should hold up pretty good but a standard TH400 will be lunch for the BB.
Remember, most HP race/street cares are a lot lighter than a K5 and you don't see many street cars running 38's.
I had a 396 in my 70 SS Chevelle that could also rip the shocks out of the body.
If you really want to consider a high HP BB you should build the truck up tough first or get ready to fix it ALL the time.
I thought of that when I built my truck and I think my one ton, 465 could handle it and I REALLY love the power of a BB.
The problem I think about is that if you use your truck for crawling (like me) the HP could cause broken parts even if you are careful so why do it?
If your running mud it could be a important plus or if you just stay on the street.
All I'm trying to say is, make sure your truck is ready for all that power before you jump.
As for the CFM, if you starve a motor of what it needs it can effect your mileage the same as going too big on a small motor.
BB's rule in well put together trucks like Shawns but don't think he can't break it /forums/images/graemlins/tongue.gif.
When you drop a high HP motor in your truck the hp will find the weakest link. If you have a TH350 the BB will eat it for lunch.
A Th400 that is well built should hold up pretty good but a standard TH400 will be lunch for the BB.
Remember, most HP race/street cares are a lot lighter than a K5 and you don't see many street cars running 38's.
I had a 396 in my 70 SS Chevelle that could also rip the shocks out of the body.
If you really want to consider a high HP BB you should build the truck up tough first or get ready to fix it ALL the time.
I thought of that when I built my truck and I think my one ton, 465 could handle it and I REALLY love the power of a BB.
The problem I think about is that if you use your truck for crawling (like me) the HP could cause broken parts even if you are careful so why do it?
If your running mud it could be a important plus or if you just stay on the street.
All I'm trying to say is, make sure your truck is ready for all that power before you jump.
As for the CFM, if you starve a motor of what it needs it can effect your mileage the same as going too big on a small motor.
BB's rule in well put together trucks like Shawns but don't think he can't break it /forums/images/graemlins/tongue.gif.
Topdown
1/2 ton status
If you want to keep the mileage as high as you can and still get more go juice, just have your 600 jetted to a 700 or a 750... shouldnt cost as much as a new carb.
just like everyone else, I think the 600 is a little small for a 454.
-Ryan /forums/images/graemlins/k5.gif
just like everyone else, I think the 600 is a little small for a 454.
-Ryan /forums/images/graemlins/k5.gif
The reason 2 bbl carbs get crappy gasmilage alot of times is that to get 400 cfm outa a 2 bbl carb you have to have big primaries since there are no secondaries and you need to flow all that air past 2 betterflys. A 600 cfm 4bbl on the other hand will have smaller primaries since if you need to flow all that 600 cfm you can flow it past 4 butterflys instead of 2 but most of the time you are just flowing a bit of that and not getting into the secondaries. Thats why most of the time a 4bbl will have better response, fule economy and if the motor can use the extra cfm more power.
You will also be suprised how little cfm a motor actually needs. Remember the old rule of thumb?
CID x RPM x V.E. / 3456 = CFM
This equation still works well, if you are using a holley or something like that when you start getting into high zoot stuff that do wet flows then you use something else.
Lets make some assumptions and do some math.
454 x 5500rpm x .85VE/3456 = 614CFM!
.85VE is a pretty good on a mild modified street motor and motors only opperate at peak volumetric efficency at a very narrow rpm range. This equation is to find your peak cfm requirement. It is based on the assumption of turning 5500 rpm max. Play around with the #'s. you wont get into a motor with 100%VE unless it is a built motor. Having too big of a carb can just make it a PITA to tune. The smaller carbs are jetted and designed from the factory with the idea joe blow will stick a 600 on a 350 and a 850 on a 454. If I were to buy a new carb for a mild 454 it would probably be a 750 vac sec. It will be jetted close from the factory for what the intended app and a little to big wont hurt bottom end or give you a funky signal and be a pain to tune. 750 edelbrock would pretty much be a bolt on deal. You might notice a few HP in the upper rpm on a dyno between all the carbs. But properly tuned any of those 3 would work fine.
You will also be suprised how little cfm a motor actually needs. Remember the old rule of thumb?
CID x RPM x V.E. / 3456 = CFM
This equation still works well, if you are using a holley or something like that when you start getting into high zoot stuff that do wet flows then you use something else.
Lets make some assumptions and do some math.
454 x 5500rpm x .85VE/3456 = 614CFM!
.85VE is a pretty good on a mild modified street motor and motors only opperate at peak volumetric efficency at a very narrow rpm range. This equation is to find your peak cfm requirement. It is based on the assumption of turning 5500 rpm max. Play around with the #'s. you wont get into a motor with 100%VE unless it is a built motor. Having too big of a carb can just make it a PITA to tune. The smaller carbs are jetted and designed from the factory with the idea joe blow will stick a 600 on a 350 and a 850 on a 454. If I were to buy a new carb for a mild 454 it would probably be a 750 vac sec. It will be jetted close from the factory for what the intended app and a little to big wont hurt bottom end or give you a funky signal and be a pain to tune. 750 edelbrock would pretty much be a bolt on deal. You might notice a few HP in the upper rpm on a dyno between all the carbs. But properly tuned any of those 3 would work fine.
4x4Freak
1/2 ton status
You cant change a carb's cfm by swapping jets. Changing jets will change the fuel mixture. The cfm is determined by the venturi size and cannot be changed without swapping carb bodies or some modification.
