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Adam Kresse2
08-10-2008, 07:17 PM
I am running an internally stock SR20, only upgrades being:
-Greddy down pipe
-Z32 Fuel Filter
-K&N Intake
-Boosting at 10psi

My car ran great, never gave me any trouble, but I drive my car hard every time I drive it. And like my last car my motor is starting to die.

I am starting to get a ticking sound, at around 3/3500 rpms when the revs are held. My friend also came across the same problem after beating up his car (his later blew up). My assumption is rod knock?

Now for the question.

I want to be able to run 10psi, and have the car handle it internally on a daily basis. Is this asking too much of a stock SR with a rebuild? Not an OEM rebuild, using forged pistons etc.

10psi is more than enough for me, so I was hoping to rebuild the bottom end and keep going? Is this feasible? Or, will after a few months of hard beating,will it blow up again? Is 10psi a lot for a built bottom end?

If a built bottom end, and otherwise stock SR20, can handle 10psi comfortably, could someone please also tell me EVERYTHING that I would require for the rebuild.

I was told by my local shop "if you're going to go through the trouble of a rebuild i would suggest the following at minimum":

- Pistons
- MLS Headgasket
- Cams
- Rods
- Port/Polish

Is that ALL I need, if not could someone please tell me every exact thing I need for it, as I will need to start a wish list lol :-/

Thanks

aNskY
08-10-2008, 07:31 PM
well cams and port / polish have nothing to do with the longevity of the build.. if anything cams will decrease the engine's lifespan. if you were going to do that stuff anyway, then that would be a good time to do it but otherwise not necessary. any agressive cam should also be paired with upgraded springs / retainers. and im suprised he didnt mention a valve job, that would be more important than cams which could easily be done later

fliprayzin240sx
08-10-2008, 09:21 PM
Umm, what were you using to add extra fuel into the engine for the extra air your pushing? im willing to bet, you were running lean and caused your engine to detonate. Thats what caused your rod bearings to fail. Stock bottom end will take alot more abuse than you give it credit, thats assuming you're taking care of it. Running the engine lean isnt taking care of it. If you're gonna rebuild the bottom end, fresh rod bearings, have the crank polished, fresh piston rings, have the block rehoned, fresh oil pump and metal HG would be a good start.

Adam Kresse2
08-10-2008, 10:35 PM
Should have put this in the first message:

I bought the car as is, and did not alter it in any way. The person who built this car, built it for his girlfriend. He was a fairly smart bud as far as 240's / SR20's were concerned (Having built over 3 sr20'd 240s, one putting down 313whp). I Only listed the mods I could visually see with my eyes. The car never ran lean, always stunk of gas.

I beat the shit out of my car, I love to get it sideways, and have to constantly remind myself not to boost EVERY time I hit the gas. But I want to be able to beat on it that hard. and not run into any problems (bottom end wise, I'm not dumb. If you beat anything that hard it will break)

Rod Bearings
Crank Polished
Piston Rings
Block Rehoned
Oil Pump
Metal HG

+ Pistons?

Does this setup sound like I could handle 10psi comfortably:

CP Forged Custom Aluminum Piston Kit 86.0mm/8.5:1
Eagle Chromoly Forged Rods
ACL Performance Main Bearings
Tomei Metal Head Gasket 87mm x 1.2mm
OEM Nissan Oil Pump With Front Cover / New Front Main Seal
Rehoned Block
Cranks Polished

Before re running 10psi:
Tomei 740cc Fuel Injectors (What is the minimum cc I should have for 10psi)
Walbro 255LPH Fuel Pump
Some type of fuel management, or alike. Most likely an SAFC.

Let me know if that sounds decent?

SleepR 240sx
08-11-2008, 12:14 AM
I know people who have run 12psi on stock blocks for over 2 years, no major problems. A built motor shouldn't have any issue handling your 10psi, and neither should your stock block. My friend is making 492 on a stock bottom end with only a rom tune and safc. He's been running that for about a year. No major issues. I really don't see how it should be a problem for your motor as long as you take care of it like the person above said. Take care of your motor, it will take care of you.

As far as the rebuild, that looks like a pretty good list of items. If your just going to be running 10psi, honestly I wouldn't bother with the forged parts, new front and rear main seals, overall general maintenance. New gaskets are always good. I can't see the point of going forged if your not really looking to push the limits on horsepower.

Adam Kresse2
08-11-2008, 02:23 AM
Do the people who push 12 psi drive the car daily?

I daily my SR and probably drift it just as much.

Have a hard time keeping off 10psi and off the revlimiter.

Would forged pistons help in this case? or no?

At this rate, am I going to continually have my engine fail on me? There has to be someone on Zilvia who beats their SR more than a couple times a week.

Basically I am torn between re building the SR and continuing on, or building a cheap ka-t, because that way when I revlimiter till my engine blows, I can just grab another ka for a couple hundred bucks and I'm good to go.

Is the rebuild going to be enough to handle 10 psi on a constant basis (i.e at least a couple hours drifting a week) or does my situation sound like I should get a more disposable engine?

summary:

SR Rebuilt with previously mentioned parts + 10psi daily beating (I can't stress enough how much I mean daily) = possible?

VQMaxFan
08-11-2008, 06:02 AM
I think you are over doing it and just throwing money and parts at the car. Esp for just 10psi. You need to read up on why people upgrade to forged internals and build bottom ends. Also send off your oil for testing and that will tell you allot about whats going on inside the motor without physically tearing down the motor.

fliprayzin240sx
08-11-2008, 09:25 AM
Should have put this in the first message:

I bought the car as is, and did not alter it in any way. The person who built this car, built it for his girlfriend. He was a fairly smart bud as far as 240's / SR20's were concerned (Having built over 3 sr20'd 240s, one putting down 313whp). I Only listed the mods I could visually see with my eyes. The car never ran lean, always stunk of gas.

I beat the shit out of my car, I love to get it sideways, and have to constantly remind myself not to boost EVERY time I hit the gas. But I want to be able to beat on it that hard. and not run into any problems (bottom end wise, I'm not dumb. If you beat anything that hard it will break)

Rod Bearings
Crank Polished
Piston Rings
Block Rehoned
Oil Pump
Metal HG

+ Pistons?

Does this setup sound like I could handle 10psi comfortably:

CP Forged Custom Aluminum Piston Kit 86.0mm/8.5:1
Eagle Chromoly Forged Rods
ACL Performance Main Bearings
Tomei Metal Head Gasket 87mm x 1.2mm
OEM Nissan Oil Pump With Front Cover / New Front Main Seal
Rehoned Block
Cranks Polished

Before re running 10psi:
Tomei 740cc Fuel Injectors (What is the minimum cc I should have for 10psi)
Walbro 255LPH Fuel Pump
Some type of fuel management, or alike. Most likely an SAFC.

Let me know if that sounds decent?


You need something better than a SAFC, SAFC cant even run 740cc injectors on its own.

Anyways, what youre trying to do is absolutely overkill. A fresh OEM rebuild would be more than enough honestly. If youre gonna go thru a full after market rebuild like that, fuck, might as well throw some bigger turbo and enjoy the fuck out of that car. GT2871R at 14 psi with that engine will be fun as fuck...And like I said, ill reiterate it again, what kills SRs are detonation (crunches the bearings) and oil starvation. Fresh pump is always a good thing since there is no way to tell the condition of the pump without an oil pressure gauge. Detonation, nothing that good tuning cant fix...

tunersedge
08-11-2008, 09:41 AM
There is really no reason to build up your motor for 10psi, stock boost on a sr20 is what 7psi and i know ive been running my motor on 10psi for the past year without a problem so go for the OEM rebuild unless you plan on more horsepower in the future.

People have taken the stock bottom end to 400whp+ so an OEM rebuild is more then enough for 10psi. Thats assuming your taking care of your car and maintaining it on the regular.

S14DB
08-11-2008, 10:03 AM
So, you want to spend thousands on rebuilding an engine but only a couple hundred on engine management?

Running pig rich at idle is a sign of bad tuning and doesn't mean you won't run lean under load.

Nissan adjusts the timing map based on load. SAFC fakes out the load to the ecu to get more fuel but doesn't account for the timing map. This causes car to run way to much advance causing detonation or to much retarded sending egt's sky high melting parts.

As far as the rebuild. I would check the decks to make sure they are flat.
* Quality head gasket
* ARP head studs.
* Replacement Pistons and rings. OEM is fine.
* Bearings
* OEM oil pump

Your goals warrant nothing more then a OEM style rebuild.

But please get a rom tune or standalone for management if you are going to crank the boost or change injectors.

Adam Kresse2
08-11-2008, 11:12 AM
Thanks for all the feed back! This is great help!

I know the injectors were overkill, I was just browsing FR sport and the Tomei ones were the cheapest, I asked which were the smallest cc I should run with 10 psi, because most likely I will grab a used set of injectors (being that my power goals are low and dont require top of the line parts)

If I rebuild to oem spec, what can I do to ensure that I can drive my car hard every day and not run into problems? Better fuel management?

By looking at the rods, rod bearings, pistons etc and it is the wrong place to be looking for reasons why my engine failed?

Basically I gather that without another good tune, no matter what I throw in the SR internally, it will detonate?

So my revised rebuild list (again feedback please!)

Oem Pistons
ACL Performance Main Bearings
Tomei Metal Head Gasket 87mm x 1.2mm
OEM Nissan Oil Pump With Front Cover / New Front Main Seal
Rehoned Block
Cranks Polished

Before re running 10psi:
Some sort of higher flowing injectors
Walbro 255LPH Fuel Pump
Some type of standalone fuel management. (What should I shoot for? My local shop can do Greddy E Manage, or Megasquirt. I want the easiest one as I am definitely not an expert tuner)


Thanks again for all the help!

Sileighty_85
08-11-2008, 11:57 AM
I know the injectors were overkill, I was just browsing FR sport and the Tomei ones were the cheapest, I asked which were the smallest cc I should run with 10 psi, because most likely I will grab a used set of injectors (being that my power goals are low and dont require top of the line parts)

Having too much fuel is better than not having enough. You keep saying 10psi, what size turbo are you wanting to run at 10 psi?

10 Psi on a T25 is gonna be nothing compared to a T67 @ 10 Psi
cuz a T67 at 10 psi will push a greater volume of air, than a T25 would at 10psi.

T25's will push 12-14psi

Regarless a stock bottom end SR20 will hold 500Hp, just get a metal H/G and some AP head studs and you'll be fine.


If I rebuild to oem spec, what can I do to ensure that I can drive my car hard every day and not run into problems? Better fuel management?


I built my engine but still running Stock ECU, Injectors and MAF and Never had a problem I've been running it for over 1 1/2 years and made many 400+ mile trips with out a problem, making 254whp @ 10psi, (T-28) but running lean after 5,500rpms

Get Haltech or Power FC.


Basically I gather that without another good tune, no matter what I throw in the SR internally, it will detonate?

Correct, The tune is the source of the engines life and Power


So my revised rebuild list (again feedback please!)

Oem Pistons
ACL Performance Main Bearings
Tomei Metal Head Gasket 87mm x 1.2mm
OEM Nissan Oil Pump With Front Cover / New Front Main Seal
Rehoned Block
Cranks Polished


Machine head
Replace Valve Guide Seals
BC Valve Springs
ARP Head Studs


Before re running 10psi:
Some sort of higher flowing injectors
Walbro 255LPH Fuel Pump
Some type of standalone fuel management. (What should I shoot for? My local shop can do Greddy E Manage, or Megasquirt. I want the easiest one as I am definitely not an expert tuner)


550cc Injectors and Z32 MAF (Depending on Turbo Size)
SARD Fuel Pressure Regulator

fliprayzin240sx
08-12-2008, 02:31 AM
Thanks for all the feed back! This is great help!

I know the injectors were overkill, I was just browsing FR sport and the Tomei ones were the cheapest, I asked which were the smallest cc I should run with 10 psi, because most likely I will grab a used set of injectors (being that my power goals are low and dont require top of the line parts)

If I rebuild to oem spec, what can I do to ensure that I can drive my car hard every day and not run into problems? Better fuel management?

By looking at the rods, rod bearings, pistons etc and it is the wrong place to be looking for reasons why my engine failed?

Basically I gather that without another good tune, no matter what I throw in the SR internally, it will detonate?

So my revised rebuild list (again feedback please!)

Oem Pistons
ACL Performance Main Bearings
Tomei Metal Head Gasket 87mm x 1.2mm
OEM Nissan Oil Pump With Front Cover / New Front Main Seal
Rehoned Block
Cranks Polished

Before re running 10psi:
Some sort of higher flowing injectors
Walbro 255LPH Fuel Pump
Some type of standalone fuel management. (What should I shoot for? My local shop can do Greddy E Manage, or Megasquirt. I want the easiest one as I am definitely not an expert tuner)


Thanks again for all the help!


Whoa, I missed that shit...car DID NOT HAVE a bigger fuel pump?!?! THATS THE FUCKING REASON THAT SHIT BLEW!!! Stock fuel pump WILL NOT keep up with an SR. Walbro would be on top of the list during the rebuild. Your engine blew to a double whammy of not enough fuel management and not enough fuel period.

Firestorm
08-12-2008, 03:30 AM
10 psi on stock turbo is absolutely no problem for a stock SR. so i suggest you just get it rebuilt, new bearings and seals, maybe a new oil pump. of course that depends on what condition your engine is in.

your main concern is to get an uprated fuel pump and a tune so your engine won't lean out under boost.

fromxtor
08-12-2008, 08:44 AM
here's my list for you:
255 lph fuel pump
Deatschwerks 550cc injectors
OEM rebuild kit (should have a HG in it)
clevite rod and main bearings
oil pump/front cover(w/ front seal)
Rom tune
Block hone
Pistons rings(i would only get pistons if yours are effed up)

DDSR240
08-12-2008, 09:04 AM
Sorry to be a thread jacker but why clevite over acl im getting my crank millid down ofter a spun rod bearing and I would like to put the proper bearings back in... BTW I am doing a biuld too..

titiaium pistons
diamond rods
space metal sleeves
no h/g i'm welding the head to the block
I'm keeping the t25 and shooting for 280 at the wheeles wish me luck...just kidding.

drifts135
08-12-2008, 09:53 PM
A couple of my buddies have had bad expieriances with acl but im not nocking them b/c there not profesional engine builders but mabye a more knowledgeble zilvian can give there 2 cents.

fromxtor
08-12-2008, 10:17 PM
Sorry to be a thread jacker but why clevite over acl im getting my crank millid down ofter a spun rod bearing and I would like to put the proper bearings back in... BTW I am doing a biuld too..

titiaium pistons
diamond rods
space metal sleeves
no h/g i'm welding the head to the block
I'm keeping the t25 and shooting for 280 at the wheeles wish me luck...just kidding.

Nascar motors use clevite, they will work in your >200hp SR.

DDSR240
08-12-2008, 10:45 PM
Is clevite what is used on most of the high hp sr's Im serious on this build
gt35r
264's
port and polished head
aem ecu
I was shooting for 450 on stock bottom end but on 10 lbs of boost it spun a rod bearing ..so know im adding cp pistons ,eagle rods and either clevite or acl for the bearings ....then i was going to shoot for 600hp but I really don't want the bearings to be my down fall and yes i now tunning will be the biggest part for me to reach 600.

aNskY
08-12-2008, 10:53 PM
i think youre gonna need more than a gt35