sr20cars

I am boosting the LS motor w/stock internals all the way through. My ecu cuts fuel @ like 7400rpm. The motor is in great shape and Im not afraid to blow it. I would like a little more rpms. Now Im not trying to blow it, but I have a set of GRS springs and retainers and would like to know what they are safe up to.

What is safe rpms on the stock LS springs, and on the GSR springs??

Any help would be appreciated and if this has been asked 500000 times, my appologies, but could not find a search for it.

How much can I boost this thing before it does blow also??

Kendall

Keep the stock revlimit. The issue here is not the valvetrain, but more the internal balance of the rotating assembly.

95lstegman

hold on a second, GS-R valve springs? in a non-VTEC head? okay . . . who sold you that?

and BTW, the stock ECU limits you to 6900rpm. the stock tachometer on probably every production vehicle reads higher than what is actually occuring.

and yes, stock rev limit is the way to not blow up your engine.

projectTeG

i have heard that a stock ls can go to 7500, but id rather just keep the stock limit and wait til you beef the engine up to beable to rev higher. valvesprings, stronger rod bolts....etc

Built to Spill

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sr20cars &raquo;</TD></TR><TR><TD CLASS="quote">How much can I boost this thing before it does blow also??</TD></TR></TABLE>

Depends on how hard you drive youre car. I wouldnt suggest boosting over 8 lbs for daily driving. Personally i would keep it around 6 if youre trying to keep youre motor for awhile.

LSRracing95

you are not going to make peak power past about 6300-6500 anyway because of how the LS head flows.
its not able to breathe well at higher rpm operation.
get a quick spooling turbo, tune right, and keep the stock rev limit and make as much reliable power possible.
if you wanted higher revs, you should have bought a VTEC from the start, so just work with what you have and dont ruin it

projectTeG

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSRracing95 &raquo;</TD></TR><TR><TD CLASS="quote">you are not going to make peak power past about 6300-6500 anyway because of how the LS head flows.
its not able to breathe well at higher rpm operation.
get a quick spooling turbo, tune right, and keep the stock rev limit and make as much reliable power possible.
if you wanted higher revs, you should have bought a VTEC from the start, so just work with what you have and dont ruin it </TD></TR></TABLE>


or instead of getting a vtec why not just get the ls head P&P. vtec isnt everything when it comes to cars. it is a great design, but its not always needed.

95lstegman

well, you can overcam the LS and make power up to 8000 or 8500rpm, but it won't be nearly the power than you could make on the same setup with nice port work. i personally recommend this since building the head up with valvetrain and cams still costs less than just the port work (at a good, REPUTABLE shop!). and you'll still have nice power, just not quite what a VTEC would have.

lVlemphizStylez

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .Richard &raquo;</TD></TR><TR><TD CLASS="quote">

Depends on how hard you drive youre car. I wouldnt suggest boosting over 8 lbs for daily driving. Personally i would keep it around 6 if youre trying to keep youre motor for awhile.</TD></TR></TABLE>

umm how can you say 6 or 8 lbs when you have NO idea the size of the turbo...you are aware that 6 psi on a larger trim turbo is not 6 psi on a smaller turbo....they will produce very different power increases....its not how much psi...because you could safely run 20 psi on a small as **** turbo netting you a 30 hp increase and your motor would be fine...

DarkDragon

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lVlemphizStylez &raquo;</TD></TR><TR><TD CLASS="quote">

umm how can you say 6 or 8 lbs when you have NO idea the size of the turbo...you are aware that 6 psi on a larger trim turbo is not 6 psi on a smaller turbo....they will produce very different power increases....its not how much psi...because you could safely run 20 psi on a small as **** turbo netting you a 30 hp increase and your motor would be fine...</TD></TR></TABLE>

the reason for this is heat. A smaller turbo has to work harder to move the same amount of air a larger turbo does. When more work is done more heat is generated thus heating the intake charge up more. Now saying the motor will be fine using 20psi and only getting 30hp is dead wrong since the low power increase would be from large amounts of heat soak of the air coming in and hot air means detonation to come. I know the 20psi and hp humber was a exageration. Also IIRC psi should be the same regardless of the tubro size since its the amount of air pressure over atmosperic pressure the motor receives, the larger turbo dosnt do as much work to produce the 6 psi as the smaller unit does so its air charge is heated less, but it did produce 6 psi regardless of the power increase

lVlemphizStylez

yes but that 6psi on the larger turbo creates more pwoer than that 6psi on the smaller turbo....which is why it should be looked at as a whp threshold of the block and not a simplistic "omg dude you cant run 8 psi"

and no psi shouldnt be the same regardless of turbo....because they produce different amounts of power...and your stock engine has a whp limit...

Built to Spill

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lVlemphizStylez &raquo;</TD></TR><TR><TD CLASS="quote">

umm how can you say 6 or 8 lbs when you have NO idea the size of the turbo...you are aware that 6 psi on a larger trim turbo is not 6 psi on a smaller turbo....they will produce very different power increases....its not how much psi...because you could safely run 20 psi on a small as **** turbo netting you a 30 hp increase and your motor would be fine...</TD></TR></TABLE>

Becuase its a safe psi to run out for a daily driver. Im not worried about power increase, my answer was pertaining to 'how long the motor will last'

lVlemphizStylez

you missed the point completely....erase your posts..

if the turbo is large enough 6 psi can blow your motor if it exceeds your motor's power limit...

DarkDragon

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lVlemphizStylez &raquo;</TD></TR><TR><TD CLASS="quote">yes but that 6psi on the larger turbo creates more pwoer than that 6psi on the smaller turbo....which is why it should be looked at as a whp threshold of the block and not a simplistic "omg dude you cant run 8 psi"

and no psi shouldnt be the same regardless of turbo....because they produce different amounts of power...and your stock engine has a whp limit...</TD></TR></TABLE>

The reason the larger turbo makes more power than the smaller one at the same psi is the heat. Larger one doesnt heat the air as much when its compressed. Colder air packs more oxygen and when its combined with fuel and a spark it make more power. Pure oxygen wont burn but makes other elemts RAPIDLY expand such as gasoline and other gases within the air we breath. The colder the air charge the more power produced

Built to Spill

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lVlemphizStylez &raquo;</TD></TR><TR><TD CLASS="quote">you missed the point completely....erase your posts..

if the turbo is large enough 6 psi can blow your motor if it exceeds your motor's power limit...</TD></TR></TABLE>

The motor is stock, theres not need to run a turbo that big.

I wont erase my posts, but i will get your account erased.

DarkDragon

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lVlemphizStylez &raquo;</TD></TR><TR><TD CLASS="quote">you missed the point completely....erase your posts..

if the turbo is large enough 6 psi can blow your motor if it exceeds your motor's power limit...</TD></TR></TABLE>

This is also true. Now a T-66 or T80 wouldnt be a good choice as they problly wouldnt even have time to produce 6psi because of the lag (yes i know a street honda motor shouldnt spoll it) A motor does have a HP limit, once its reached and exceded then things will break. Now PSI from FI does play a part, since increased cylinder pressures can lead to damage before the hp limit it reached but thats where tuning comes in. With the extra cylinder pressure tuning needs to take place to compensate for it. If propper tuning is used a boosted motor can last just as long as a N/A motor

lVlemphizStylez

erase my account and show me based on what grounds it was to be erased...

and dark dragon saw my point....you should take notes from him seeing as he actually understands its not a simplistic psi setting....but there is more to it than that

DarkDragon

to answer your question keep teh stock rev limit. The LS rod ratio isnt that of a VTEC motor so if reved higher then the added stress will take its toll. Many people who have rasied their revlimits on LS have been OK for awhile but in the end the motor comes apart. With increased revs the first to go on a LS are usally the rod bolts. With higher revs the cylinder walls also take more of a load due to the angle of which the crank is at and the speed that the piston is traveling. The loads can oval a cylinder wall which wont be too good for sealing, lol. VTEC springs wont interchange to a non vtec but type r inner springs can be used on VTEC motors. For your set up id use either a T3/T4 or a T3-60. They are both used on hondas and match pretty well. They are usally the turbos in a kit for a honda unless its a GREDDY kit which used a frankenstine mitsubishi/greddy combo IHI, I beleive its a 14G maybe a 16G but not as big as used on the EVO. Im not saying a LS wont make power higher, cuz they can but the setup must warrent it. If higher revs are needed then sleeving should be looked into, maybe coated skirts on the pistons, forged pistons with ARP rod bolt and forged rods

TABIAS

if you want to be safe (for the motor) the highest limit of boost i would run would be 10psi with proper tuning. Anyting over that is kinda risky.

DarkDragon

thast almost the higher a stock motor will alow you to run since the MAP sensor will throw a check engine light when it sees 11psi. but a GM 3 bar unit could be swapped in.. but you ment other things, i know

Built to Spill

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lVlemphizStylez &raquo;</TD></TR><TR><TD CLASS="quote">erase my account and show me based on what grounds it was to be erased...

and dark dragon saw my point....you should take notes from him seeing as he actually understands its not a simplistic psi setting....but there is more to it than that</TD></TR></TABLE>

lol, simplistic psi setting.

My comment was general, I said i would keep it around 6psi for a daily driver. Give or take depending on tuning etc. You are looking way too indepth of my posts, and Im glad you decided to get butt hurt over it. It makes me smile.

lVlemphizStylez

i apologise for my thought process being too analytical for your simplistic approach to a problem

id rather someone be actually informed by facts than by your generalizations which can lead to problems for someone else reading this

Built to Spill

The OP didnt specify any type of turbo size etc. I get tired of asking questions becuase the OP was to broad. Im also tired of reporting threads, because more like this show up. Therefore, ive resulted to this method.

TABIAS

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DarkDragon &raquo;</TD></TR><TR><TD CLASS="quote">thast almost the higher a stock motor will alow you to run </TD></TR></TABLE>


the most you mean?

TABIAS

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lVlemphizStylez &raquo;</TD></TR><TR><TD CLASS="quote">id rather someone be actually informed by facts than by your generalizations which can lead to problems for someone else reading this</TD></TR></TABLE>


I think your talking to someone who knows a bit more than you think sir. Richard has been around for a while. And since you havn't been here for a while, I wouldn't reccomend smarting off to anyone else


Modified by TABIAS at 3:36 PM 12/5/2005