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

 

[GSGoinFast]

14.5 psi stock? if that were the case wouldnt the engine be pushing 280hp stock. If you do the math, 14.7 psi is normal atmospheric pressure. boost is the amount of extra air being pushed in. if 7 psi of boost is being pushed, its half the atmospheric pressure, therefore your engine is theoretically pushing 50% more power. If the 4g63 n/a pushes 140hp like the 420a, because there both similar with the same sizes, or even 135hp like the n/a 4g63 of the 1g's, then a 50% increase would put it up to 210hp, like the factory says it is. so shouldnt it be running 7 psi?

 

[DSMeclipse4G63]

stock boost should be 10-11psi...your luck to get that stock. I was running 9psi at wot stock and when I installed a 1g bov it held 13psi till about 5.5k. Now that I have a 1g tb and ported stock mani and other assortments my t25 holds 15-16psi right up to when I shift at about 6.1k6.2k. Get a 1g bov or after market the boost will go up to maybe 14-15psi, which means you wont need a mbc or ebc till you upgrade your turbo.
Andrew

edit: hey did you get that job at tri state? iof so(or not) I need some advice on so damage I have on my car. If your not busy of course.

 

[IMMORTALSPYDER]

Aight I got some time behind the wheel tonight and sometimes it is at 14-14.5. I got a 1G bov along with some other assortments coming so we'll see what happns when that stuff gets here.

Ya I did get the job at Tristate, but I have to quit cuz I'm getting surgery done and will be out of work for a while. I'll problaby go back to my other job for now cuz of health insurance reasons. I can still check out your car if you want to meet up sometime.

 

[Spoolin95DSM]

I just installed my boost gauge yesterday,and im installing my n1 catback,hi-flow cat,and mbc today.I was just wondering how much should I raise the boost on the stock turbo.I dont wanna go and blow my turbo.I plan on getting an EVO3 Big 16G in the near future though

 

[psychlow]

First - GET A 1G BOV.

Then turn up your boost level with the MBC.

The limiting factor right now is that 2G BOV. If you try to boost high levels on it, you'll vent out your boost through the BOV and overspin the turbo because it'll never build enough boost to open the wastegate with that MBC on there.

 

[Spoolin95DSM]

I shouldve mentioned this but I have a HKS SSQV already installed on my car

 

[Eclipse96Ryder]

15-16 lbs of boost.

I just turned the boost from 9 to 16 on my 1g awd...holy shit man, its such a huge difference.

 

[psychlow]

Originally posted by Spoolin95DSM
I shouldve mentioned this but I have a HKS SSQV already installed on my car

Heh, I should've checked your profile!

 

[Spoolin95DSM]

does 12-13 psi sound safe enough?

 

[xcelr8n]

yes!

 

[doodie]

The T25 can run up to 16lbs. But the boost dropps off after 5500rpm.

 

[Spoolin95DSM]

I havent even raised the boost yet and it reads about 13 psi.Is that normal?Should I raise it a little?

 

[dave99gst]

a even 15 psi is safe. ya can bump it to 18 if ya really wanna with a rewired pump. but after 15 yer just blowing mostly hot air at a higher pressure with tha T-25 compaired to acualy flowing more CFM's

 

[gaddis]

See my mod list for details on what I have. What are you guys running on a similar setup. I just installed my 50 trim and fmic, and am starting to tune for <2deg knock with DSMlink. I'm thinking about running ~22psi on pump and ~24 on C16. Does that sound about right?

 

[BOMEX DSM]

You cant boost more than 22psi on the stock head studs as they arent strong enough, that much pressure will cause the head to lift leaving you with a lot to clean . Replace the studs with some ARP fasteners and a new headgasket and you should be fine. Hope that helps

 

[gaddis]

Guess what, headgasket blew at only 19psi. I didn't see knock over 3deg except for a couple of times, and never more than 6. I'm replacing it with the Mitsu metal headgasket and ARP headstuds. Should be stronger than ever in about a week.

 

[TSiAWD666]

You can change the head bolts to arp studs/nuts without removing the head btw. Just do it one at a time.

Wish I could tell you what psi is safe as far as knock goes, but I haven't been able to datalog my 50 trim yet at high boost. I did datalog 22psi on 93 octane unleaded and didn't see any timing pull, but haven't datalogged at anything higher.

 

[DSMJim]

I ran my car at 24psi on pump gas a few times with stock gasket and studs with no problems, all on pump 94. Not sure why yours blew at 19psi thats not common at all. I have heard of 2G motors with stock gasket and studs going 26psi but not sure how long.

Regardless 22-23psi should be ok for the stock stuff, just don't run that daily.

 

[Violater101]

I agree with Jim. I wouldn't run anymore than that though without upgrading to some ARP's personally (just not worth the risk). I run anywhere from 18-20psi with no problems. I don't see how only 3 degrees of knock caused the HG to let go. I guess stranger things have happened, but I would think its quite rare.

 

[GSntncT]

I've ran as high as 28(accidental ) without blowing it. My high is currently set to 25, and my stock internals held up. It is really old that it blew at only 19psi. If I were you, get a low-high boost controller. I can switch from 16 to 25 psi at a blink of an eye.

However, I'm not saying you can run 25 all the time and be fine. 99% of the time, I daily around at 16 psi.

 

[gaddis]

My engine had 140,000 miles on the stock head gasket which probably played a role in it's failure. Although around 5K miles ago, back in September before I started modding, compression was 160-170 across the board. I do have a cockpit adjustable manual boost controller, and since I have AWD don't see much need to go electronic.

Since I already have to take the head off, I'm thinking about doing some internal work while I'm at it. Any suggestions?

 

[RuBiCaNT5X]

One thing to mention for those of you with stock internals putting ARP Headstuds in, you might be tempted to go with a metal gasket, but I would suggest going with a stocker gasket. I talked to Tevenor about it and suggest it because if something were to go wrong, inside the engine, running lean or boost creep, you are going to want your headgasket to blow rather than throwing a rod or exploding a piston. Fixing an HG is alot more cost effective than replacing internals...

 

[ditchmagnet]

ok...i got my boost gauge back yesterday...and i hooked it up...everything is good cause when it is off it points to 0, and when it is at idle it goes to -18, and decel is -22, anyway...ive done the bcs mod already...and so when i take it out to test the gauge...my max boost is 9 psi...thats not right is it? and i the turbo can go higher cause my boss, (who used to have a 10 sec talon,) took off the hose coming from the wastegate, and it hit 20, (just for a test, didnt go down the road,) so whats up? i am mostly stock on everything.
thanks all.

 

[xcelr8n]

9psi isnt horrible, check for leaks, also i remember reading you could do the bcs mod incorrectly and be stuck at only 9psi or so.

someone else will have to chime in for the last point i made though. not 100%

 

[ditchmagnet]

oh, and another thing...what does the cheap aquarium mbc look like? and how do you install it? i did try to search...but i didnt find anything. and ive never hear of the bcs leaving you at 9psi....all i did was remove that plastic part....