Gt30r-0.82 Vs Ct355-0.63

[king]

Hey guys.

I dont know exactly wich turbo i want, my goal is 500Bhp , streetuse ,sometimes drag/sprint.

Had the GT30 on my eyes, with a HTA Billet compressor wheel, but spoke to some people about other options, so i need some help.

I know Bram has a CT355 ,but unfortunaly he has his engine allready out of his sold car so that i cant take a testdrive

I dont think im going to port my head and have RS2 Cams.
Whole engine has been refurbished when turbo comes on.

What you guys think, can i reach my goal of 500Hp with the CT355-0.63 with non-porting head and ADU cams?

Or should i stick with the GT30?
And the cams , stick with the ADU cams or put in a 7A cam?

And how much Hp should i get extra if im gonna let the head ported?

A lot of qeustions on a sunday

[prj]

Without porting your head it is no point to go really large turbo.
If you want to keep stock head, my advice is GT3071. It should get you about 380-400whp, which will be close to your goal.
Or you can try GT3076.

In both cases you will either need standalone ecu or MAF replacement on stock ECU.

[king]

Without porting your head it is no point to go really large turbo.
If you want to keep stock head, my advice is GT3071. It should get you about 380-400whp, which will be close to your goal.
Or you can try GT3076.

In both cases you will either need standalone ecu or MAF replacement on stock ECU.

With the GT30R i mean the GT3076-0.82 , sorry.

Thought i want to keep my good old mototronic, i heard today about the MAF.
Maybe VEMS is a solution , but have no any idea how that works or how expensive that is

Im putting a lot of money in the engine, new pistons, rods, engine is completly new within a few weeks.
Gt3071 is not a option for me, 1 size bigger i want

[Jamo]

Move MAF to pressure side you don't need to remove it, if keeping stock ecu, MRC are running cars over 600 bhp in this format.

[prj]

Move MAF to pressure side you don't need to remove it, if keeping stock ecu, MRC are running cars over 600 bhp in this format.

Putting MAF to pressure side does not work properly, it's temperature correction is not meant for that. The MAF only reads to about 350bhp as well.
Please don't talk in absolutes when you have no experience with tuning cars with over 400hp on Motronic.

To make it run properly on motronic you /need/ a MAF conversion, and you /need/ to properly map the ECU. Without a proper MAF, all fuel injected over 350 is guesswork and mapped to last column, which will cause rich spots and poor running.
As for turbo, you can use GT3076 compressor and K26 hotside.

[king]

Forget the 3071 it's good but it's half in half out. You can run both without porting the head quite easily, if you do port you will gain in all areas if done correctly.

There is no right or wrong answer here,

If it were me I'd take the CT355 if you are going to port the head

look at the rwd19t thread on ported heads for his over 500 bhp results with a 3076r .63 and a ported head and less bhp on a 3076.82 on a stock head.

you don't need MAF replacement if you move it too the pressure side instead of the intake side

No right or wrong aswer here Thanx a lot jamo , im in doubt ,this is helpfull hehehe Just kidding

Had read the the topic from rwd19t about the results with non-porting and porting.

Cant make up my mind on wich turbo i want or porting and cams
I have some weeks to go to make up my mind.

So if headporting the CT355 is the best choiche from these 2, how much BHP can i get with porting and a CT355-0.63

[Jamo]

Putting MAF to pressure side does not work properly, it's temperature correction is not meant for that. The MAF only reads to about 350bhp as well.
Please don't talk in absolutes when you have no experience with tuning cars with over 400hp on Motronic.

To make it run properly on motronic you /need/ a MAF conversion, and you /need/ to properly map the ECU. Without a proper MAF, all fuel injected over 350 is guesswork and mapped to last column, which will cause rich spots and poor running.
As for turbo, you can use GT3076 compressor and K26 hotside.

I know the maf is maxed out good tuners tune to the map once 5v limit is hit.

plenty of 400 plus bhp car mapped in the UK with no issues using these methods
for the past 5 years

I don't know who you are but it's only recently seen you posting and now offering tuning!

[Jamo]

No right or wrong aswer here Thanx a lot jamo , im in doubt ,this is helpfull hehehe Just kidding

Had read the the topic from rwd19t about the results with non-porting and porting.

Cant make up my mind on wich turbo i want or porting and cams
I have some weeks to go to make up my mind.

So if headporting the CT355 is the best choiche from these 2, how much BHP can i get with porting and a CT355-0.63

Better off speaking directly to repo who supplies and maps to these turbos

[rs200]

well I take CT355 0.63 A/R and think that I will hit 480 hp, with NO ported head and motronic ECU..

maybe the CT355 with 3BB can get a higher pressure easier than BB... both turbos are super , you can't miss.. take the chipper one

[A80Avant]

CT355, i have no experience other than watching the videos that Bram had. GT3076/0.82AR is what im using now.

Spool wise on stock head (again what im using now) will give you roughly 4000rpm for full boost on 3d gear, and 3800 on 4th gear. (by full boost i mean anything above 2bar). %

5th and 6th sooner, but dont expect anything happening on those gears before 3000rpm for the 0.82AR

I believe that the 355 on the .63AR will spool faster but will also produce high amount of EGT if you keep the boost high, as Bram said, he had more than 1000C on high rpm.

I will throw another option on the table and that is the new precision range that 034 has and i believe that the 3076R equivalent would be better than the 3076R 0.82AR on top boost vs rpm on our engines. With the 0.82AR i have no issues with EGTs whatsoever and i run 0.78lamda at most on high boost. Never went above 970C (EGT sensor on the EM collector)

If i were to have a choice i wish garrett was making a 0.70-0.75AR on this turbo,and that would give the best result. Im only going to go for porting a head in the future and keep the 0.82 as is.

Overall, i feel the 0.82 is at MY borderline of street use on the 2.2l engine. Having said that, if middle range is what you are after and not 500hp, then 3071R with 0.63AR will give you a wonderful mid range responce and 420hp(crank) on non ported head ADU.

hope it helps.

[A80Avant]

Dmitri, also when you talk about horse power, we usually mean crank, not whp. to claim that a 3071 will make 400whp (wheel power) on an S2/RS2, this means that it will be able to make somewhat 480 crank, which has never been done or proven on a stock engine/stock head, unless you tune perhaps with race fuel or E85.

[prj]

I have dynosheet from 3071 at 380whp.

[A80Avant]

i can give lots of dyno sheets that can say whatever you want them to say. And those are words from respectable dyno operators. So personally i dont believe them. I managed to get to 425crank hp measured on street conditions with the perfoamance box through accceleration equations, inputing weight, air drag,wheel drag and finally a percentage of diff losses which can be manipulated. Even saying so, 380whp can mean anything from 400-480hp crank depending on what type of dyno. If it was a hob dyno, you usually add a 12.5% as losses only (eg rototest dyno). so that makes 427.4hp crank

[prj]

Yes, I agree with you. Dyno should be used as tuning tool, not measuring tool.
That hp number was with meth injection.

[Jamo]

Nice work Jamo, deleting my posts, so you can be "right".
I'll cut the explanations then.


B/S. Motronic does not use MAP.

You said 600hp, now 400hp?

I did not say map sensor I said map i.e ecu map

MRC own S2 is running over 600 hp, so are other gt35 cars out there

If you wish to speak to me pm me. I don't know your history and don't intend to pretend to know however there are plenty of happily running cars out there with MAF on the pressure side and running big hp in the u.k MRC tuned.

Or do you care to dispute these cars are mapped incorrectly?