Stock Boost [Merged 5-7]

[Gs-tHaVoC]

hehe kinda dumb question but whats stock boost on my car? just wondering if its worth it to install a boost controller and gauge without bov thats all. thanx

 

[v2ner]

i've seen 32psi on race fuel, afc, studs, ML HG.

 

[v2ner]

oops, forgot about the camshafts.

 

[95blackGsTurbo]

What turbo were you using that you ran 32psi on stock internals? H.P. wise internals are good for a solid 400-450hp. I've heard of people getting more but I wouldn't try it personally.

 

[L8TR V8S]

I was using a evo III big 16g... i was only running 22 psi not 32 i dont have the money to fix my car if something goes wrong at 32 psi... thats crazy our cars can run 400 hp with stock internals, thanks

 

[DSMcrazy3]

11.7:1 is "perfect" AFR.

I thought 14.7:1 was the "perfect" AFR??

 

[project_tsi]

I run 25-26 psi on 93 oct. w/ no knocking, on my stock 6 bolt bottom end.

 

[ahaidet]

John Shepherd told me he was running 10's on the stock pistons, rings, rods, and crank. Not sure how much horsepower that amounts to but I am sure its a bunch.

 

[ddavisaf]

I thought 14.7:1 was the "perfect" AFR??

Actually I think you're right....
I'll verify and let you know...
I knew that my number wasn't looking right for some reason.

 

[L8TR V8S]

My shop said 11: 1 is where you want to be and im somewhere in there

 

[DSMcrazy3]

I know 14.7 is the "stoichiometric" ratio number, at sea level. Lemme know when you find it

 

[ddavisaf]

Bah bah black sheep have you any wool...



The best advice I could give to you would get it to 12.3:1... It's a great tune for the DD and weekend warrior.

 

[SkyLineGtR-R34]

i think you can run more than 400 hp on stock internals...but not for long

 

[v2ner]

i think 600 hp on stock internals is fine we have two cars runnin around that area. both are 6-bolts w/ camshafts, studs, and ML HG. one was runnin the SC-61 while the other was runnin the 35R. same turbo but the 35R lasts longer in the long run. both are runnin 110 boostin 28 psi. bone stock internals except for camshafts. both daily driven. the 32 psi was on a 35R but i wouldn't recommend boostin that high for a daily driver. i've never heard of anybody goin over 32 psi on stock internals.

 

[Deadly BlaZe]

i've searched but couldn't find a rock solid answer. I'm sure this isn't right, but my boost peaks at 6-7 psi. what's the stock amount?

 

[weith1111]

More than that. You have boost leaks my friend. 11psi sounds familiar for some reason...

 

[crunchymilk]

if you're mods are correct as in the profile, it should be either a MASSIVE boost leak (check that, it's in the vfaq) or maybe even an exhaust leak. My money is on the boost leak.

 

[cky]

hi guys I'm new to dsm's i just bought a 98 gst and was just curious how much boost a stock motor can handle any info is greatly appreciated thanks
-ryan

 

[Spookcorleone]

The stock motor can handle the stock turbo just fine. I wouldn't see much more reason for running over 16 PSI (providing you have a Boost gauge, controller, and maybe a aftermarket / 1G Blow off valve.) - it would be pointless to really go past that from what I hear as you would be over-working your turbo, and over-heating your intercooler.

As to what it can run with another performance turbo - with supporting mods and so forth, ALONG with the engine being rather new (... EX. Don't boost the hell out of a engine with 120K miles on it.) they run around 20 safely (pump gas) from what I understand.

Again, thats a shady' question because you can't really boost alot with a larger turbo and supporting mods (injectors, SAFC, fuelpump - so forth.) with out considering your weak, used, tired, old head-gasket.

 

[BoOsTeDFwD20G]

hey buddy I think that you will be fine as long as you take car of the maintenance and do everything step by step I am still running stock seven bolt and head with just bolt ons and a 20g turbo and I am running 22 psi on pump gas and I only got a felpro head gasket so just take care of the maintenance then after that it is all you and how you tune your car to determine the boost that you can run

 

[alexsmede]

22 PSI? Do you have any supporting mods to that? If you dont, you might wannt consider it, first mistake is upgrading the turbo on a car.

Anyways, they say you can push 2-3 PSI above stock. You will need a boost controller to do this which you can either make your own or buy one off ebay for $30. You dont now want to turn your turbo above 20 PSI on stock internals unless you have a bunch of supporting mods such a a fmic. So follow the DSMTech Guide and you will be in good shape... Good Luck

*If you though this was helpful, please give me some reputations points*

 

[95blackGsTurbo]

You need to stop asking for rep. points. If they find it helpful they will give them. And 22psi on a stock motor is fine. I used to have a 2g, hence my name and I ran 24psi at the track on a 16g with COMPLETELY stock internals and gaskets, besides exhaust manifold gasket without a front mount intercooler and I never once had a problem. Did this for almost 3 years and the day I sold my car it was 3 points under perfect compression. Tuning is VERY important on high psi motors. You can run some really good numbers with a completely stock longblock and not worry about anything as long as everything is set right. I had mine done right and it never had a problem once. On a 2g upgrading the turbo as a first mod isn't really a mistake. It's what I did when I had mine ran my turbo at stock psi til I got the rest of the upgrades. Stock motors are made to handle 450+ hp stock with just a simple headgasket change. That's about all I have done to my motor now in my 1g along with 1g big rods and 2g pistons for some more compression and it hasn't missed a beat. You will only have problems if you start getting stupid and start running 18psi on stock turbo stock fuel or throw a bigger turbo on a turn the boost up til you either hit fuel cut or melt a pistons. Maintainance is a big thing with our cars. I've learned that over the years. Depending on what you are running for a turbo and fuel and tuning you can easily get into the 20 psi range with stock internals and headgasket.

 

[andymoraitis]

hi guys I'm new to dsm's i just bought a 98 gst and was just curious how much boost a stock motor can handle any info is greatly appreciated thanks
-ryan

Ryan,

It all depends on what type of supporting mods you have. The big keys in being able to make strong power on stock internals are:

1. Fuel supply
2. Ability to maintain a cool intake charge
3. Ability to minimize knock
4. Optimizing air/fuel ratios and timing

If you have a stock turbo, it doesn't pay to turn it up more than a few psi as mentioned above since the T-25 is pretty weak. Cranking the boost will contribute to it's early death. However, as you progress and formulate a game plan that encompasses all four of the elements I mentioned above, you'll be able to sustain higher and higher boost levels (to a point).

As an example, I run 20 psi on pump gas with 23 degrees of timing advance and an 11.7:1 air/fuel ratio with stock internals, head bolts and head gasket. I've run as high as 23 psi on 110 leaded race/pump gas mix and 26 psi on straight 110 with the same setup. As a general reference point, as you get closer to the magic 400 crank horsepower number, then you'll need to consider upgrading internals, although many have gone beyond this with a simple head stud and head gasket change.

Hope that helps,

Andy

 

[v2ner]

~23 psi w/out head studs (pump gas) turbo:EVO III, SC-61/35R
~32 psi w/studs, ML HG, camshafts, (110 octane) turbo:SC-61/35R

all this has been seen and done. stock valves, guides, rods, pistons, etc...

 

[Mist3r Spool]

22 PSI? Do you have any supporting mods to that? If you dont, you might wannt consider it, first mistake is upgrading the turbo on a car.

Anyways, they say you can push 2-3 PSI above stock. You will need a boost controller to do this which you can either make your own or buy one off ebay for $30. You dont now want to turn your turbo above 20 PSI on stock internals unless you have a bunch of supporting mods such a a fmic. So follow the DSMTech Guide and you will be in good shape... Good Luck

*If you though this was helpful, please give me some reputations points*

I'd have to disagree, I run 20psi all day. Anyone can argue about how much power the stock engine can handle. The bottom line is that it's based on proper tuning & religous maintenance.

 

[CanadianTSi]

I'd have to disagree, I run 20psi all day. Anyone can argue about how much power the stock engine can handle. The bottom line is that it's based on proper tuning & religous maintenance.

Agree'd.

I run 24psi daily on my stock motor(stock headgasket too) with my 50 trim. 220,000kms on it also