# Still have turbo problems



## 142BHP (Jul 21, 2004)

Hello Guys

After I blew my headgasket I installed a cometic steel gasket but this might sound stupid but my blow off valve doesn't sound like it used to. Under high boost it simply dumps on one loud PSSSST where it used to make a nice sequential sound , under low boost it still sounds the same. Now I have come across this problem when i had a boost leak but checked all out and there is no leaks, could I have done something wrong when I installed the head or could something else have changed.

The second thing I can't seem to sort out is overheating under hard driving, should I go to a bigger radiator or is the standard one supposed to be fine.

Cheers


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## velardejose (Sep 9, 2004)

Hi
More gas = more power = more thermal load
About that 'sequential' (I dont get/understand it) bov sound, maybe there are some rerouted lines after the head gasket replacement
Peace


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## asleepz (Feb 24, 2004)

Maybe your BOV is set to hard in the first place. Unless it's a HKS SSQV, you shouldn't be making a flutter sound.


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## velardejose (Sep 9, 2004)

After rereading this thread...
Blown hg? Maybe you have timing or lean a/f ratio issues...
I have some heating but under long hill boosting...
Daily (spirited) driving, no heating
Temp is in the same range as before going turbo
Maybe its because I only run 7 psi...
Peace


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## dburone (Apr 2, 2004)

With my bov, if y set it hard it does that secuential sound, but if y let it a little loose i sounds with ins single pssst.


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## SuperSentra4203 (Dec 17, 2002)

Unless you have a BOV that is designed to do the sequential sound (aka Turkey Call) you do not want it to. This is bad!!


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## 142BHP (Jul 21, 2004)

I give up  

They can't seem to sort out my car at the tuners. I asked them to set my AFR to 11.5 under boost and that is what we done, the car seems to have picked up a bearing nock after all the crap I had and i am thinking strongly of replacing the motor with a red top SR20DET motor.

everytime you run a bit of boost through that damn motor the heat guage climbs quicker than the rev counter. They reckon the overheating the whole time caused to bearing to start knocking from the oil thining out and bla bla bla you know the story. They think that somehow the turbo is pressurising the water but I dont know hoe the hell that can happen.

I am running out of options here guys what do you think I should do. If I have to replace the motor I think you would all agree to go for the DET instead of the DE.

Cheers


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## SuperSentra4203 (Dec 17, 2002)

uhhhh, AFR of 11.5, i'm no genius, but even I know that is bad. Typically boosted motors want an AFR 13.5 if i'm not mistaken.


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## wes (Apr 30, 2002)

SuperSentra4203 said:


> uhhhh, AFR of 11.5, i'm no genius, but even I know that is bad. Typically boosted motors want an AFR 13.5 if i'm not mistaken.


WHOA slow down tiger. That is an NA AFR. Boosted cars want 11.5 with 12.0 being the lean side of things. 

Sounds to me like you have a blown head gasket. Have you done a compression and leak down test and have yo properlybled the colling system? 

Also are you running the water lines throught he turbo?


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## velardejose (Sep 9, 2004)

You had a blown hg...
Have you checked the head for warping?
If it is warped you need to resurface it, then replace the hg and assemble it again
Peace


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## 142BHP (Jul 21, 2004)

After the HG blew i resurfaced the head just to clean things up and I installed a cometic steel headgasket cause it is supposed to handle boost a bit better. I dont know of somehow i missed something and maybe there is still leakage through one of the water ports.

Compression readings on all 4 cylinders run between 120 and 125 which I think is about standard, by bleading the water system what do you mean by that, I know it sounds stupid but when you fill your radiator with the cap off all the air should bleed out the top not right, I know there is a air bleed screw on the thermostat housing but I have loosened this bolt and nothing happens. As for the leak down test I am not 100% sure how to do that ( please inform)

Cheers Guys


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## wes (Apr 30, 2002)

142BHP said:


> After the HG blew i resurfaced the head just to clean things up and I installed a cometic steel headgasket cause it is supposed to handle boost a bit better. I dont know of somehow i missed something and maybe there is still leakage through one of the water ports.
> 
> Compression readings on all 4 cylinders run between 120 and 125 which I think is about standard, by bleading the water system what do you mean by that, I know it sounds stupid but when you fill your radiator with the cap off all the air should bleed out the top not right, I know there is a air bleed screw on the thermostat housing but I have loosened this bolt and nothing happens. As for the leak down test I am not 100% sure how to do that ( please inform)
> 
> Cheers Guys


120-125 compression normal?? :jawdrop: 

That is FAR from normal, was that done with the motor warm and the TB open?


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## 142BHP (Jul 21, 2004)

I am taking the engine out this weekend to open things up and see what the hell is going on inside there, if there is a bearing shot do you guys think I should buy a DET motor or while I have to redo the motor maybe go for some better rods and some forged pistons too or am I getting ahead of myself here.

I know everybody says how strong the SR20 lump is supposed to be but I am getting scared over here guys since this thing only ran for like 3 weeks including about 2 1/2 weeks at the tuners  

Cheers


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## 142BHP (Jul 21, 2004)

I am sure that is what my Haynes manual also referred to ( a reading between 110 and 130 is fine if I remeber correctly) please correct me if I am wrong and what should the readings be according to you.

Cheers


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## psuLemon (Apr 23, 2003)

142BHP said:


> I am sure that is what my Haynes manual also referred to ( a reading between 110 and 130 is fine if I remeber correctly) please correct me if I am wrong and what should the readings be according to you.
> 
> Cheers


i believe it should be closer to 200 IIRC


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## wildmanee (Nov 21, 2004)

Do you guys a pressure measurement different from PSI? I noticed your username BHP, are you in Britain?


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## SuperSentra4203 (Dec 17, 2002)

wildmanee said:


> Do you guys a pressure measurement different from PSI? I noticed your username BHP, are you in Britain?


BHP refers to 'brake horsepower'


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## 142BHP (Jul 21, 2004)

Measurement was done in PSI and 200 sounds very high to me since even when I built a 13-1 CR NA motor I think i only touched about 190 PSI. The 142BHP is when i started tinkering with my NA motor that is what the dyno read, so now I'm craving at least another 100 with the turbo .

By the way I am from the good ol South Africa where we have to beat someone up to get good parts for the SR20DE 

We are opening everything up again this weekend so I will keep you posted but I think that the headgasket is still not sealing.

Cheers


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## 142BHP (Jul 21, 2004)

My mistake 
I checked both the Haynes Manual and my car again, the Haynes manual says a reading of 178 PSI for the SR20 and about 200 PSI for the GA16. 
I also rechecked my engine with the TB wide open and get a reading around 155 PSI, i think I did not have my TB wide open.

Cheers


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## OverTake (Feb 7, 2006)

142BHP said:


> My mistake
> I checked both the Haynes Manual and my car again, the Haynes manual says a reading of 178 PSI for the SR20 and about 200 PSI for the GA16.
> I also rechecked my engine with the TB wide open and get a reading around 155 PSI, i think I did not have my TB wide open.
> 
> Cheers





If you did the compression chech and get a reading from 120-140 There is a leak. The ga16 should be around 170-200 PSI


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## OverTake (Feb 7, 2006)

According to my reasearch it shouldnt past 200 psi.


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## wildmanee (Nov 21, 2004)

SuperSentra4203 said:


> BHP refers to 'brake horsepower'


Read what I said, I know this. I'm wondering if since he's from Britain (they use a different horsepower measure over there, hence BHP) that he might also be using a different pressure measurement. Reading comprehension = Good.


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## psuLemon (Apr 23, 2003)

wildmanee said:


> Read what I said, I know this. I'm wondering if since he's from Britain (they use a different horsepower measure over there, hence BHP) that he might also be using a different pressure measurement. Reading comprehension = Good.


im pretty sure hes from england IIRC for when he posted pics of his car in member ride section.


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## velardejose (Sep 9, 2004)

Hi
Even a forged head, block, pistons, rods, crankshaft, pins, (you-name-it) engine will fail if run lean when boosted
I see two paths
1. You can learn how and where to tune a non factory boosted engine, could be discouraging and expensive if you have no shops in your area that know how to do it right... (Thats what happened to me)
2. Buy a complete sr20det and just have fun with the factory setting
Keep us posted
Peace


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## 142BHP (Jul 21, 2004)

My plan at the moment is to buy a SR20 DET and fit the bigger turbo I bought for the factory DE motor its a T3/T04E with a it's spools up very nicely and I make boost from about 3000 rpm and running full boost at 4500 rpm, and I am sure this baby is good for enough horses to satisfy anyones needs 

Cheers


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