How high can rev a fully-built syty engine?
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Silly
Banned
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
Stock block is the limit, bowtie has better oiling, then you can always add a dry sump.
I have seen a Ty go to roughly 10k give or take before at Nationals in 2000.
I personally rev mine to 8k without the dry sump.
Re: How high can rev a full-built syty engine?
Stock block is the limit, bowtie has better oiling, then you can always add a dry sump.
I have seen a Ty go to roughly 10k give or take before at Nationals in 2000.
I personally rev mine to 8k without the dry sump.
turbodig
Active member
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
My question would be.... why? Most of the cams normally used in Turbo motors are going to be long past their sweet spot at that point.
You'd have to have some heavily worked Vortecs to support that.
Our motors make their power at low RPMs.. you don't need to spin them to make power.
That being said, the rods will be the least of your worries, although the weight of the eagles makes them poor candidates for high revs. You will need something other than stock valvetrain, including springs and rockers.
The mail bearing oiling in the stock block will likely become an issue.
Re: How high can rev a full-built syty engine?
My question would be.... why? Most of the cams normally used in Turbo motors are going to be long past their sweet spot at that point.
You'd have to have some heavily worked Vortecs to support that.
Our motors make their power at low RPMs.. you don't need to spin them to make power.
That being said, the rods will be the least of your worries, although the weight of the eagles makes them poor candidates for high revs. You will need something other than stock valvetrain, including springs and rockers.
The mail bearing oiling in the stock block will likely become an issue.
1madgumby
New member
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
I have the same combo, hit 5,100 the other day no problums.
Re: How high can rev a full-built syty engine?
I have the same combo, hit 5,100 the other day no problums.
autoaddictions
Active member
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
with a soild roller cam you can go to 7500 but cross your fingers. Itake mine with hyd. roller to 7000. Vortech heads though.
Re: How high can rev a full-built syty engine?
with a soild roller cam you can go to 7500 but cross your fingers. Itake mine with hyd. roller to 7000. Vortech heads though.
ty166
Donating Member
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
then subtract around 300 rpm and you should have max rpm...
Re: How high can rev a full-built syty engine?
then subtract around 300 rpm and you should have max rpm...
Ry368
one mile = 5280 feet
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
:rotf::tup:
Ratfink749
Greasy and proud.
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
How high any engine can rev is going to be dependant upon the camshaft specs and the durability of the valvetrain (and quality of parts used) Yes.. once you get into higher RPM's issues like rotating assembly balance and Rod and piston weight will play into the equation as well. If you rev high enough you'll either Lose power because the cam isnt designed for that high of a range, or Float valves because the springs cant handle it, Float lifters because they can't be pushed back down agains the camshaft fast enough, or vent the block via a broken rod/piston. Top engine RPM should be determined by a combination of head and intake flow capability, Camshaft lift/duration/timing (which will also be determined based on compression ratio), and the exhaust system's ability to get rid of all of the spent gasses. Just throwing on a few random parts and hoping for a higher redline is NOT the way to go. Back to OP's question: I would base the answer on which camshaft you have in it, Take a look at the power band its designed for.. or a Dyno sheet for that matter. I'd rev it to the point of peak power, then shift! once the power band starts going back down the slope.. what's the point of continuing to rev it?
Re: How high can rev a full-built syty engine?
How high any engine can rev is going to be dependant upon the camshaft specs and the durability of the valvetrain (and quality of parts used) Yes.. once you get into higher RPM's issues like rotating assembly balance and Rod and piston weight will play into the equation as well. If you rev high enough you'll either Lose power because the cam isnt designed for that high of a range, or Float valves because the springs cant handle it, Float lifters because they can't be pushed back down agains the camshaft fast enough, or vent the block via a broken rod/piston. Top engine RPM should be determined by a combination of head and intake flow capability, Camshaft lift/duration/timing (which will also be determined based on compression ratio), and the exhaust system's ability to get rid of all of the spent gasses. Just throwing on a few random parts and hoping for a higher redline is NOT the way to go. Back to OP's question: I would base the answer on which camshaft you have in it, Take a look at the power band its designed for.. or a Dyno sheet for that matter. I'd rev it to the point of peak power, then shift! once the power band starts going back down the slope.. what's the point of continuing to rev it?
blk00z28
Forced to by choice
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
I think Hoovers oddfire was spinning close to 10k. But your talking about a 30k bowtie motor.
I plan to rev somewhere around 6500. Just have to see when its all back together.
Re: How high can rev a full-built syty engine?
I think Hoovers oddfire was spinning close to 10k. But your talking about a 30k bowtie motor.
I plan to rev somewhere around 6500. Just have to see when its all back together.
gkrcr882
SyTyless......for now!
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
No point in making it spin faster than it needs to. As many have mentioned, with the airflow characteristics and the basic design (5.7/350 base) there isn't much need to spin these engines up. They have enough NVH problems as is :lol: . My SHO, however, loved to sing- the redline was 7500, but they have been taken past 8300 without problems. Thing is, it was a 24 valve DOHC engine, and with the secondary intake runners open it moved a ton of air.
Re: How high can rev a full-built syty engine?
No point in making it spin faster than it needs to. As many have mentioned, with the airflow characteristics and the basic design (5.7/350 base) there isn't much need to spin these engines up. They have enough NVH problems as is :lol: . My SHO, however, loved to sing- the redline was 7500, but they have been taken past 8300 without problems. Thing is, it was a 24 valve DOHC engine, and with the secondary intake runners open it moved a ton of air.
Z SKI
Donating Member
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
I look at it this way, if i can make this (http://www.syty.net/forums/showthread.php?t=64879) type of power only spinning to 5400 rpm or so then whats the need to stress everything and try to spin to 6000+ rpm. My build is very similar to this CA build and I will be super happy if I dont need to rev over 5500 rpm. And as Dig said these motors make all their power down below so why try to make them a high winding screamer if you dont have to??:2cents:
See ya,
Re: How high can rev a full-built syty engine?
I look at it this way, if i can make this (http://www.syty.net/forums/showthread.php?t=64879) type of power only spinning to 5400 rpm or so then whats the need to stress everything and try to spin to 6000+ rpm. My build is very similar to this CA build and I will be super happy if I dont need to rev over 5500 rpm. And as Dig said these motors make all their power down below so why try to make them a high winding screamer if you dont have to??:2cents:
See ya,
JSM
Active member
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
The most you probably want to me spin is 110% of peak HP. 5200 peak in that example ZSKI posted, your only looking at 5720rpm. Say 6k at most.
I really think your trying to bring in what we would call "ricer" car ways into syty world.
Jeremys stock turbo truck we shift at a little over 4k rpm, rpm drops down to 2500ish at some point and trucks really starts to want to go.
Use the torque we make, honda's, small motors, even NA motors don't make the torque we do, so RPM is all they have left.
Re: How high can rev a full-built syty engine?
The most you probably want to me spin is 110% of peak HP. 5200 peak in that example ZSKI posted, your only looking at 5720rpm. Say 6k at most.
I really think your trying to bring in what we would call "ricer" car ways into syty world.
Jeremys stock turbo truck we shift at a little over 4k rpm, rpm drops down to 2500ish at some point and trucks really starts to want to go.
Use the torque we make, honda's, small motors, even NA motors don't make the torque we do, so RPM is all they have left.
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
So i dont wanna bring a ricer-setup in your community.
But high rpm=power, thats the same on every engine! I wanna built a complite setup where everything fits together. I wanna use a GTK-650 turbo. Those turbos needs rpm to get the right flow it needs. Al lot of dragcars rev higher than the syty engine...
I dont wanna go with the flow, i wanna use the potential the engine got. I wanna built my engine where everthing works together and not only put power out from boost.
Re: How high can rev a full-built syty engine?
So i dont wanna bring a ricer-setup in your community.
But high rpm=power, thats the same on every engine! I wanna built a complite setup where everything fits together. I wanna use a GTK-650 turbo. Those turbos needs rpm to get the right flow it needs. Al lot of dragcars rev higher than the syty engine...
I dont wanna go with the flow, i wanna use the potential the engine got. I wanna built my engine where everthing works together and not only put power out from boost.
turbodig
Active member
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
Absolute myth.... I know many guys who make double or triple the power of guys who run high revs on the same CI motor... with 1/2 the RPM.
It has been said by guys wiser than I, RPM = Ruin's People's Motors.
In the end, it's your $, do what you like. But the advice you're gonna get from reliable people around here is going to point you to a lower revving engine. A high RPM motor will only empty your pockets faster.
Re: How high can rev a full-built syty engine?
Absolute myth.... I know many guys who make double or triple the power of guys who run high revs on the same CI motor... with 1/2 the RPM.
It has been said by guys wiser than I, RPM = Ruin's People's Motors.
In the end, it's your $, do what you like. But the advice you're gonna get from reliable people around here is going to point you to a lower revving engine. A high RPM motor will only empty your pockets faster.
Ratfink749
Greasy and proud.
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
All that about hi revving high HP and low revving high torque engines also gets into the arguments of being oversquared or undersquared and the rod ratios and all that other crap.. Typically "Large bore Short stroke" revs high for power, and "Long stroke with matching or smaller bore" makes more torque down low. Stroker motors are traditionally Torque monsters where as short strokers (GM 302 for example..) (YES GM made a 302 for those who dont know... ) Rev like there is no tomorrow and have high HP but fairly low torque numbers. And yeah.. as its been said.. High RPM usually costs more and is much more likely to self destruct a lot faster than a slower revving engine would.
Re: How high can rev a full-built syty engine?
All that about hi revving high HP and low revving high torque engines also gets into the arguments of being oversquared or undersquared and the rod ratios and all that other crap.. Typically "Large bore Short stroke" revs high for power, and "Long stroke with matching or smaller bore" makes more torque down low. Stroker motors are traditionally Torque monsters where as short strokers (GM 302 for example..) (YES GM made a 302 for those who dont know... ) Rev like there is no tomorrow and have high HP but fairly low torque numbers. And yeah.. as its been said.. High RPM usually costs more and is much more likely to self destruct a lot faster than a slower revving engine would.
blk00z28
Forced to by choice
Re: How high can rev a full-built syty engine?
Re: How high can rev a full-built syty engine?
We clearly do not need rpm to make big power, the basic 4.3 v6 that is in our truck is not a "dragcar" and while some do rev higher, they do not make the power we, or even the Buick 3.8's make on a lower rpm. If you want a drag car, build a motor made for pure racing.
If you can make the same amount of "flow" at 4800 rpm then you can at 8800rpm, whats the point in spinning it that high? The only thing your going to cause is way to much pressure in the cylinders.
If you want a motor that makes great power and not from boost then you own the wrong car. What you are looking for is a N/A motor. Not a forced induction motor. But somehow I doubt you are going to agree, or even see the advice given to you in this thread. So its your money, spend it how you will. Just don't expect to many people to reply to a thread where you aski how to build it again once you blow it up thinking its a 4 banger. :2cents:
Re: How high can rev a full-built syty engine?
You seriously need to use the search feature and read.
We clearly do not need rpm to make big power, the basic 4.3 v6 that is in our truck is not a "dragcar" and while some do rev higher, they do not make the power we, or even the Buick 3.8's make on a lower rpm. If you want a drag car, build a motor made for pure racing.
If you can make the same amount of "flow" at 4800 rpm then you can at 8800rpm, whats the point in spinning it that high? The only thing your going to cause is way to much pressure in the cylinders.
If you want a motor that makes great power and not from boost then you own the wrong car. What you are looking for is a N/A motor. Not a forced induction motor. But somehow I doubt you are going to agree, or even see the advice given to you in this thread. So its your money, spend it how you will. Just don't expect to many people to reply to a thread where you aski how to build it again once you blow it up thinking its a 4 banger. :2cents: