how many lbs of boost can a stock 5s head handle....im not worried abt. the internals just the actual head.
how many lbs of boost - 6G Celicas Forums
c. this question is impossible to answer
15PSI - 30MPG - Megasquirt Tuned
200 psi 
Seriously, You might outflow the F head but it is not gonna blow because of boost.
Head gasket is another story.
Seriously, You might outflow the F head but it is not gonna blow because of boost.
Head gasket is another story.
_Gary
i thought u could crack the head w/ too much boost so i wasnt sure if ne1 has ever done it b4...do yall know how much stock pistons can handle...
to many unkown factors to answer that question accurately.
psi is a very vague measurement of how much pressure the engine isn't ingesting. and not to much is known about the limits of the 5fste except it can handle a good beating.
psi is a very vague measurement of how much pressure the engine isn't ingesting. and not to much is known about the limits of the 5fste except it can handle a good beating.
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why do you ask ?
how much power do you want to make ?
the more the boost the more the bottom end will hate you ... the head will be fine ... the "head" is more affected by raising rpm limits than it is by having boost in it...
the thing is say you want to make 300hp out of a 5sfe... it will take ALOT of boost on the stock head.... if you cam it , or oversize the valves, or port it properly it will take less psi to make the same hp figure... that's really how the head comes into the equation...
how much power do you want to make ?
the more the boost the more the bottom end will hate you ... the head will be fine ... the "head" is more affected by raising rpm limits than it is by having boost in it...
the thing is say you want to make 300hp out of a 5sfe... it will take ALOT of boost on the stock head.... if you cam it , or oversize the valves, or port it properly it will take less psi to make the same hp figure... that's really how the head comes into the equation...
2005 MB C200 Kompressor- K&N, Apexi WS2 Catback, DIY Voltage stabilizer, Intrax Springs, H&R RR swaybar, VDO Boost Gauge @ 6psi, Greddy L7 plugs, +0 Rear tiresTo Do: E-manage Ultimate tuned up to 12psi
o...well do u think stock pistons can handle 15psi? not daily but i dont want to build a motor w/ stock pistons thinkin it can hanle the power and not...thats all i was wonderin....basically wat do i need for 15 safely? maybe thats a better way of putting it.
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on what turbo? 15psi on a ct26 like i have, and 15psi on the holset that itchy has are two very different things.
the problem with running high boost on a 5sfe is not with the strength of the pistons or the head. its with the fact that its a high compression motor. the higher the compression, the more chance you have to run into detonation when trying to turn up the boost on pump gas. detonation is what ends up killing pistons, rods, headgasket, etc...
QUOTE(Kerr1 @ Aug 1, 2007 - 8:13 PM) [snapback]584481[/snapback]
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wat do i need for 15 safely? maybe thats a better way of putting it.
wat do i need for 15 safely? maybe thats a better way of putting it.
on what turbo? 15psi on a ct26 like i have, and 15psi on the holset that itchy has are two very different things.
the problem with running high boost on a 5sfe is not with the strength of the pistons or the head. its with the fact that its a high compression motor. the higher the compression, the more chance you have to run into detonation when trying to turn up the boost on pump gas. detonation is what ends up killing pistons, rods, headgasket, etc...
15PSI - 30MPG - Megasquirt Tuned
>
Would water/alcohol injection resolve this? I've been reading up on the devil's own kit and am seriously considering it being that I already run 15 degrees timing and I'd like to run more but I get pinging from 91 octane, but If I went with DO's W/A I. the effective octane would be 110+....
QUOTE(lagos @ Aug 1, 2007 - 10:10 PM) [snapback]584526[/snapback]
>
>
on what turbo? 15psi on a ct26 like i have, and 15psi on the holset that itchy has are two very different things.
the problem with running high boost on a 5sfe is not with the strength of the pistons or the head. its with the fact that its a high compression motor. the higher the compression, the more chance you have to run into detonation when trying to turn up the boost on pump gas. detonation is what ends up killing pistons, rods, headgasket, etc...
>
QUOTE(Kerr1 @ Aug 1, 2007 - 8:13 PM) [snapback]584481[/snapback]
>
wat do i need for 15 safely? maybe thats a better way of putting it.
wat do i need for 15 safely? maybe thats a better way of putting it.
on what turbo? 15psi on a ct26 like i have, and 15psi on the holset that itchy has are two very different things.
the problem with running high boost on a 5sfe is not with the strength of the pistons or the head. its with the fact that its a high compression motor. the higher the compression, the more chance you have to run into detonation when trying to turn up the boost on pump gas. detonation is what ends up killing pistons, rods, headgasket, etc...
Would water/alcohol injection resolve this? I've been reading up on the devil's own kit and am seriously considering it being that I already run 15 degrees timing and I'd like to run more but I get pinging from 91 octane, but If I went with DO's W/A I. the effective octane would be 110+....
so low compression pistons wouldnt b a bad way to start? Im trying to find a ct26 now...is there a diff. between the mr2 one and the supra one? cuz i think i might b able to buy the supra one for like 50 bucks practically new.?
Low compression would be a good start if you wanted to build the engine.
since your talking about dropping some money into the 5sfe id recommend just swapping in a 3sgte and put the money into that.
the potential of the 5sfe isnt as great as the 3sgte, depending on how far you want to take it.
The supra ct26 has a different downpipe flange to it, you would have to custom make a downpipe to use it. also it flows a hair more on the exhaust side than the mr2 ct26, its also single entry where the mr2 ct26 is twin entry. The easiest route is to use the celica/mr2 ct26.
since your talking about dropping some money into the 5sfe id recommend just swapping in a 3sgte and put the money into that.
the potential of the 5sfe isnt as great as the 3sgte, depending on how far you want to take it.
The supra ct26 has a different downpipe flange to it, you would have to custom make a downpipe to use it. also it flows a hair more on the exhaust side than the mr2 ct26, its also single entry where the mr2 ct26 is twin entry. The easiest route is to use the celica/mr2 ct26.
Visit My Automotive & Tech Blog.
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it wouldnt totally resolve it, but it sure would help a lot. for you, since your NA, using WI is going to be tricky, because its a system that is normally triggered by boost.
QUOTE(king_wsk @ Aug 2, 2007 - 6:20 AM) [snapback]584599[/snapback]
>
>
Would water/alcohol injection resolve this? I've been reading up on the devil's own kit and am seriously considering it being that I already run 15 degrees timing and I'd like to run more but I get pinging from 91 octane, but If I went with DO's W/A I. the effective octane would be 110+....
>
QUOTE(lagos @ Aug 1, 2007 - 10:10 PM) [snapback]584526[/snapback]
>
>
on what turbo? 15psi on a ct26 like i have, and 15psi on the holset that itchy has are two very different things.
the problem with running high boost on a 5sfe is not with the strength of the pistons or the head. its with the fact that its a high compression motor. the higher the compression, the more chance you have to run into detonation when trying to turn up the boost on pump gas. detonation is what ends up killing pistons, rods, headgasket, etc...
>
QUOTE(Kerr1 @ Aug 1, 2007 - 8:13 PM) [snapback]584481[/snapback]
>
wat do i need for 15 safely? maybe thats a better way of putting it.
wat do i need for 15 safely? maybe thats a better way of putting it.
on what turbo? 15psi on a ct26 like i have, and 15psi on the holset that itchy has are two very different things.
the problem with running high boost on a 5sfe is not with the strength of the pistons or the head. its with the fact that its a high compression motor. the higher the compression, the more chance you have to run into detonation when trying to turn up the boost on pump gas. detonation is what ends up killing pistons, rods, headgasket, etc...
Would water/alcohol injection resolve this? I've been reading up on the devil's own kit and am seriously considering it being that I already run 15 degrees timing and I'd like to run more but I get pinging from 91 octane, but If I went with DO's W/A I. the effective octane would be 110+....
it wouldnt totally resolve it, but it sure would help a lot. for you, since your NA, using WI is going to be tricky, because its a system that is normally triggered by boost.
15PSI - 30MPG - Megasquirt Tuned
>
if your going to drop the compression on the 5sfe, you might as well just go with a 3sgte swap. youll get a low compression motor, with a turbo, injectors, and ecu that can handle 15psi on a ct26, just fine. it would probably cost you the same as your motor build up, and the sky is the limit if you want to make more power down the road.
QUOTE(Kerr1 @ Aug 2, 2007 - 7:24 AM) [snapback]584606[/snapback]
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so low compression pistons wouldnt b a bad way to start? Im trying to find a ct26 now...is there a diff. between the mr2 one and the supra one? cuz i think i might b able to buy the supra one for like 50 bucks practically new.?
so low compression pistons wouldnt b a bad way to start? Im trying to find a ct26 now...is there a diff. between the mr2 one and the supra one? cuz i think i might b able to buy the supra one for like 50 bucks practically new.?
if your going to drop the compression on the 5sfe, you might as well just go with a 3sgte swap. youll get a low compression motor, with a turbo, injectors, and ecu that can handle 15psi on a ct26, just fine. it would probably cost you the same as your motor build up, and the sky is the limit if you want to make more power down the road.
15PSI - 30MPG - Megasquirt Tuned
for WI on an NA im pretty sure they use an rpm & wot trigger just like nitrous.
Visit My Automotive & Tech Blog.
>
91 octane? y don't you run 93?
QUOTE(king_wsk @ Aug 2, 2007 - 5:20 AM) [snapback]584599[/snapback]
>
>
Would water/alcohol injection resolve this? I've been reading up on the devil's own kit and am seriously considering it being that I already run 15 degrees timing and I'd like to run more but I get pinging from 91 octane, but If I went with DO's W/A I. the effective octane would be 110+....
>
QUOTE(lagos @ Aug 1, 2007 - 10:10 PM) [snapback]584526[/snapback]
>
>
on what turbo? 15psi on a ct26 like i have, and 15psi on the holset that itchy has are two very different things.
the problem with running high boost on a 5sfe is not with the strength of the pistons or the head. its with the fact that its a high compression motor. the higher the compression, the more chance you have to run into detonation when trying to turn up the boost on pump gas. detonation is what ends up killing pistons, rods, headgasket, etc...
>
QUOTE(Kerr1 @ Aug 1, 2007 - 8:13 PM) [snapback]584481[/snapback]
>
wat do i need for 15 safely? maybe thats a better way of putting it.
wat do i need for 15 safely? maybe thats a better way of putting it.
on what turbo? 15psi on a ct26 like i have, and 15psi on the holset that itchy has are two very different things.
the problem with running high boost on a 5sfe is not with the strength of the pistons or the head. its with the fact that its a high compression motor. the higher the compression, the more chance you have to run into detonation when trying to turn up the boost on pump gas. detonation is what ends up killing pistons, rods, headgasket, etc...
Would water/alcohol injection resolve this? I've been reading up on the devil's own kit and am seriously considering it being that I already run 15 degrees timing and I'd like to run more but I get pinging from 91 octane, but If I went with DO's W/A I. the effective octane would be 110+....
91 octane? y don't you run 93?
proud =3sgte SWAPPED= '95 Celica ST owner [calling it the GT2 or half-trac]309,000 miles n' ....dead-> ALIVE AGAIN!! ~14,000 miles driven
cali only gets 91. still, if your pinging on 91, then its probably a good idea to back off the timing.
15PSI - 30MPG - Megasquirt Tuned
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
>
its going to cost you more then 2grand to rebuild the motor, lower the compression, turbo it, and tune it.
QUOTE(Kerr1 @ Aug 2, 2007 - 5:36 PM) [snapback]584762[/snapback]
>
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
its going to cost you more then 2grand to rebuild the motor, lower the compression, turbo it, and tune it.
15PSI - 30MPG - Megasquirt Tuned
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idk...im gettin a lot of parts REALLY Cheap....yea...itll prolly cost a lil more but still not 4g's and by the time im done itll put down more power than the 3s...at a lower price...the only thing im "iffy" abt. is i kinda want the all wheel drive but....i still want the 5s motor tho....sooooo
QUOTE(lagos @ Aug 3, 2007 - 1:30 AM) [snapback]584808[/snapback]
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its going to cost you more then 2grand to rebuild the motor, lower the compression, turbo it, and tune it.
>
QUOTE(Kerr1 @ Aug 2, 2007 - 5:36 PM) [snapback]584762[/snapback]
>
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
its going to cost you more then 2grand to rebuild the motor, lower the compression, turbo it, and tune it.
idk...im gettin a lot of parts REALLY Cheap....yea...itll prolly cost a lil more but still not 4g's and by the time im done itll put down more power than the 3s...at a lower price...the only thing im "iffy" abt. is i kinda want the all wheel drive but....i still want the 5s motor tho....sooooo
you do realize that most 3s swaps are not awd, right?
what turbo are you planning to use?
what turbo are you planning to use?
15PSI - 30MPG - Megasquirt Tuned
>
without some SERIOUS headwork, you WILL NOT make more power than the 3s.
trust me, i know.
you should think about a power level you would like to acheive, then use as little boost as you can to get there.
QUOTE(Kerr1 @ Aug 2, 2007 - 5:36 PM) [snapback]584762[/snapback]
>
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
without some SERIOUS headwork, you WILL NOT make more power than the 3s.
trust me, i know.
you should think about a power level you would like to acheive, then use as little boost as you can to get there.
Former Team 5SFTE pro member ;)13.6@108MPH, 5SFTE Powered
yea...i know....but if i did it thats how it would b....b/c thats the way they r supposed to b. Prolly ct26 from a 7mgte supra. a downpipe wont b hard to make at all....and i got a friend who can make an adaptor from the manifold to the turbo.
>
U dont think w/ mr2t pistons i can make more power than a 3s? same internals but it would b on a 2.2...idk....mayb im just wastin my time and money...but right now its all i got....and i just think it would b somethin diff. to build a 5s instead of just doin a swap. (just a matter of pesonal opinion for me) when i get done in a couple of months....plannin on christmas as my "deadline" ill let u know how its goin.
QUOTE(presure2 @ Aug 3, 2007 - 10:28 AM) [snapback]584909[/snapback]
>
>
without some SERIOUS headwork, you WILL NOT make more power than the 3s.
trust me, i know.
you should think about a power level you would like to acheive, then use as little boost as you can to get there.
>
QUOTE(Kerr1 @ Aug 2, 2007 - 5:36 PM) [snapback]584762[/snapback]
>
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
without some SERIOUS headwork, you WILL NOT make more power than the 3s.
trust me, i know.
you should think about a power level you would like to acheive, then use as little boost as you can to get there.
U dont think w/ mr2t pistons i can make more power than a 3s? same internals but it would b on a 2.2...idk....mayb im just wastin my time and money...but right now its all i got....and i just think it would b somethin diff. to build a 5s instead of just doin a swap. (just a matter of pesonal opinion for me) when i get done in a couple of months....plannin on christmas as my "deadline" ill let u know how its goin.
I'm going to have to agree with just snagging a 3SGTE, if you just watch a few of the importers they will run specials. A few months ago you could snag a caldina ST215 motor/ecu/wiring harness with AWD tranny for 1800 plus shipping. I got my ST185 with 34k miles for 1800 shipped. Your best bet is to wait for a deal if your motor isn't already shot. But, your money.
-Dustin
-Dustin
whats your horsepower goal for the car?
15PSI - 30MPG - Megasquirt Tuned
>
"mr2 pistons" wont help you make more power.
they wont fit.
like i said, if your looking to make over 300whp on a 5s, 5-6k is a "cheap" estimate.
just to get the head to flow close to what the 3s does, your looking at 2k+ in headwork, + cams.
then, a built bottom end.
then EMS,
then tuning.
thats not even talking about building a turbo kit thats capable of makeing 300whp.
QUOTE(Kerr1 @ Aug 3, 2007 - 7:29 AM) [snapback]584920[/snapback]
>
>
U dont think w/ mr2t pistons i can make more power than a 3s? same internals but it would b on a 2.2...idk....mayb im just wastin my time and money...but right now its all i got....and i just think it would b somethin diff. to build a 5s instead of just doin a swap. (just a matter of pesonal opinion for me) when i get done in a couple of months....plannin on christmas as my "deadline" ill let u know how its goin.
>
QUOTE(presure2 @ Aug 3, 2007 - 10:28 AM) [snapback]584909[/snapback]
>
>
without some SERIOUS headwork, you WILL NOT make more power than the 3s.
trust me, i know.
you should think about a power level you would like to acheive, then use as little boost as you can to get there.
>
QUOTE(Kerr1 @ Aug 2, 2007 - 5:36 PM) [snapback]584762[/snapback]
>
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
for the 3sgte swap its like 4000 and thats if u do the wrk urself....im not plannin on spendin that much...in the end ill prolly have put at the most 1/2 that. and have the same or more power....but it would only b 2 wheel drive.
without some SERIOUS headwork, you WILL NOT make more power than the 3s.
trust me, i know.
you should think about a power level you would like to acheive, then use as little boost as you can to get there.
U dont think w/ mr2t pistons i can make more power than a 3s? same internals but it would b on a 2.2...idk....mayb im just wastin my time and money...but right now its all i got....and i just think it would b somethin diff. to build a 5s instead of just doin a swap. (just a matter of pesonal opinion for me) when i get done in a couple of months....plannin on christmas as my "deadline" ill let u know how its goin.
"mr2 pistons" wont help you make more power.
they wont fit.
like i said, if your looking to make over 300whp on a 5s, 5-6k is a "cheap" estimate.
just to get the head to flow close to what the 3s does, your looking at 2k+ in headwork, + cams.
then, a built bottom end.
then EMS,
then tuning.
thats not even talking about building a turbo kit thats capable of makeing 300whp.
Former Team 5SFTE pro member ;)13.6@108MPH, 5SFTE Powered
troof ^
15PSI - 30MPG - Megasquirt Tuned
the stock compression ratio will limit you to 8-12psi depending on weather the turbo is on the bigger side of things or the smaller side of things ... (the bigger the turbo the higher you'll be able to boost before you run out of octane and detonate).
so now you say you'll just drop the CR... sure, it will cost you 400 for JE or SRP custom 5sfe pistons... so now you can run 15psi possibly but you are limited to 240hp @15psi @ 5200rpms no matter what turbo you use (the head just wont be able to outflow that much... )
if your goal is 300hp on a stock head with the lowered CR it will take about 20psi to do it by my math...
a head that flows 19% more (like a 3sgte head) can do 300hp @ 15psi @ 6200 rpms
as for the water injection for the normally aspirated car... more timing isn't always more power... you already obviously have too much timing in it... if you add WI and you add even more timing you will lose your rod bearings from the added timing...
See at idle your oil pressure is low because hte rpm's are low... too much timing advance will mean that power is delivered and pounded down on your pistons/rods earlier than it should be (which is how you end up with detonation) ...
adding base timing is not the same as adding timing up top via an EMS or adding boost at higher rpms with the help of water injection...as when the rpms are up, the oil pressure is higher so there's less possibility for bearing failure...
... i wrote too much
so now you say you'll just drop the CR... sure, it will cost you 400 for JE or SRP custom 5sfe pistons... so now you can run 15psi possibly but you are limited to 240hp @15psi @ 5200rpms no matter what turbo you use (the head just wont be able to outflow that much... )
if your goal is 300hp on a stock head with the lowered CR it will take about 20psi to do it by my math...
a head that flows 19% more (like a 3sgte head) can do 300hp @ 15psi @ 6200 rpms
as for the water injection for the normally aspirated car... more timing isn't always more power... you already obviously have too much timing in it... if you add WI and you add even more timing you will lose your rod bearings from the added timing...
See at idle your oil pressure is low because hte rpm's are low... too much timing advance will mean that power is delivered and pounded down on your pistons/rods earlier than it should be (which is how you end up with detonation) ...
adding base timing is not the same as adding timing up top via an EMS or adding boost at higher rpms with the help of water injection...as when the rpms are up, the oil pressure is higher so there's less possibility for bearing failure...
... i wrote too much
2005 MB C200 Kompressor- K&N, Apexi WS2 Catback, DIY Voltage stabilizer, Intrax Springs, H&R RR swaybar, VDO Boost Gauge @ 6psi, Greddy L7 plugs, +0 Rear tiresTo Do: E-manage Ultimate tuned up to 12psi
im plannin on doin head wrk to the new 1 im buying....that i get done for FREE....my uncle has all the tools for it.
the mr2t pistons wont fit if i bore it .020? i think thats how much bigger they r....but i havent researched the height yet....ne1 know?