Buddy has a 2008 Subaru STI and is making 70hp over stock with his mods. He bought Amsoil 10w30 (ATM) and is wondering if he should put 5w30 in (as Subaru calls for 5w30).
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Subaru STI
- Thread starter pistolpete
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That power comes from 8-10 add psi of boost. Should this be considered when deciding oil weight? Might the 10w30 be better, at least for summer?
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I doubt you'd see any difference between the two. The only advantage I would see to the 10w would be better shear resistance, and I assume if you own a modified sti you're probably on pretty short OCI's anyway.
In winter I would definitely change to the 5w, even in Maryland.
In winter I would definitely change to the 5w, even in Maryland.
Originally Posted By: pistolpete
Buddy has a 2008 Subaru STI and is making 70hp over stock with his mods. He bought Amsoil 10w30 (ATM) and is wondering if he should put 5w30 in (as Subaru calls for 5w30).
IMO, the ATM would be a bit better for a modded STI. Subaru calls for a 5W-30 for fuel economy and many other grades are allowed depending on your driving conditions (10W-30, 10W40, SAE 30, 40, 20W-50).
5W-40 diesel oils are really popular in subie turbo's and there are several uoa's in the uoa forum on Rotella T. I'm using Amsoil SSO on my stock 2.5T Forester and RonJitsu here is running it in his modified 2.5T WRX.
UOA on SSO in a modified WRX
UOA on Rotella in a modified STI
I would probably go with a 5W-40 with 70 hp over stock. Amsoil has DEO. Do you know what kind of mods (Cobb Tuning AccessPort Stage X, protuned, etc.)?
Although he should do a uoa at around 5k miles to see how the ATM is holding up.
-Dennis
Buddy has a 2008 Subaru STI and is making 70hp over stock with his mods. He bought Amsoil 10w30 (ATM) and is wondering if he should put 5w30 in (as Subaru calls for 5w30).
IMO, the ATM would be a bit better for a modded STI. Subaru calls for a 5W-30 for fuel economy and many other grades are allowed depending on your driving conditions (10W-30, 10W40, SAE 30, 40, 20W-50).
5W-40 diesel oils are really popular in subie turbo's and there are several uoa's in the uoa forum on Rotella T. I'm using Amsoil SSO on my stock 2.5T Forester and RonJitsu here is running it in his modified 2.5T WRX.
UOA on SSO in a modified WRX
UOA on Rotella in a modified STI
I would probably go with a 5W-40 with 70 hp over stock. Amsoil has DEO. Do you know what kind of mods (Cobb Tuning AccessPort Stage X, protuned, etc.)?
Although he should do a uoa at around 5k miles to see how the ATM is holding up.
-Dennis
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Originally Posted By: bluesubie
Originally Posted By: pistolpete
Buddy has a 2008 Subaru STI and is making 70hp over stock with his mods. He bought Amsoil 10w30 (ATM) and is wondering if he should put 5w30 in (as Subaru calls for 5w30).
IMO, the ATM would be a bit better for a modded STI. Subaru calls for a 5W-30 for fuel economy and many other grades are allowed depending on your driving conditions (10W-30, 10W40, SAE 30, 40, 20W-50).
5W-40 diesel oils are really popular in subie turbo's and there are several uoa's in the uoa forum on Rotella T. I'm using Amsoil SSO on my stock 2.5T Forester and RonJitsu here is running it in his modified 2.5T WRX.
UOA on SSO in a modified WRX
UOA on Rotella in a modified STI
I would probably go with a 5W-40 with 70 hp over stock. Amsoil has DEO. Do you know what kind of mods (Cobb Tuning AccessPort Stage X, protuned, etc.)?
Although he should do a uoa at around 5k miles to see how the ATM is holding up.
-Dennis
Stage 2 Cobb with down pipe.
Originally Posted By: pistolpete
Buddy has a 2008 Subaru STI and is making 70hp over stock with his mods. He bought Amsoil 10w30 (ATM) and is wondering if he should put 5w30 in (as Subaru calls for 5w30).
IMO, the ATM would be a bit better for a modded STI. Subaru calls for a 5W-30 for fuel economy and many other grades are allowed depending on your driving conditions (10W-30, 10W40, SAE 30, 40, 20W-50).
5W-40 diesel oils are really popular in subie turbo's and there are several uoa's in the uoa forum on Rotella T. I'm using Amsoil SSO on my stock 2.5T Forester and RonJitsu here is running it in his modified 2.5T WRX.
UOA on SSO in a modified WRX
UOA on Rotella in a modified STI
I would probably go with a 5W-40 with 70 hp over stock. Amsoil has DEO. Do you know what kind of mods (Cobb Tuning AccessPort Stage X, protuned, etc.)?
Although he should do a uoa at around 5k miles to see how the ATM is holding up.
-Dennis
Stage 2 Cobb with down pipe.
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