[quote author=KENC link=topic=17767.msg217449#msg217449 date=1252263324]
Would that kind of power level put strain on the gearbox? would i be better off going for the 18g due to mine running low boost?
Mark, you keep refering too what you are running boost wise now.. it has no relevance to putting a bigger turbo on and im not getting the point your trying to make with it??
It makes me think that you are wanting to put a bigger turbo on and not get mapped again for it
..
If you want to know the power rating on your box .. its said to be 400bhp max.. after that your on borrowed time.. however torque is more of a killer than bhp, and seen as do you are staying 2ltr i dont think you will have to worry about it too much,the way you launch your car and what clutch you have will have effect on box aswell as power
Again i dont understand why you keep refering to your 1.35 bar boost on vf24.... if you put an 18g on it will probably be mapped to its max output, whether that is at 1.2 or 1.5 etc etc.. if you are not going to try get max out of 18g you might aswell stay with vf24 imo ofcourse..
A turbo has a power rating, thatsbased on how much that turbo can flow, if you have a turbo thats maxd at 350bhp and at 1.35.. if you boost it to 2bar you still wont get anymore than the 350bhp, it physically cannot push anymore air through it....
My fear of the 18g is that up high in the revs it mite run out of puff for you, and there is nothing worst than that.. every engine has differnt characteristics
but i reckon a set of injectors, front mount and a 20g with around 1.4bar will see you close or on 380bhp and that will be ok on your box..
this is from Andy forrests site, where he seems to have dropped the 18g. he also mentions the md series
AFP5-20 - this is also a variation on the TD05. This time fitted with a much larger, high efficiency 20G compressor wheel and compressor housing. The high efficiency compressor allows the turbo to run at a lower rpm whilst still producing boost. This results in similar spool up to the 5-16 but with a 50bhp increase in airflow capability. This was the turbo used on our own RA to produce 440bhp (running fuel additives) . Up to 400 bhp is typically achievable in conjunction with full supporting modifications .
This turbo is very effective on the 2.0 and also 2.5 conversions with 1 bar+ boost coming in around 2600rpm on the 2.5
£795 new or £550 exchange (includes 12 months warranty)
We now stock the excellent MD321 series turbos, these turbos are still 'bolt-on' in the original position. They utilise the latest garrett ball bearing cores and fully ported IHI exhaust housings.
The MD321H is ideally suited to 2.0/2.1 ltr engines aiming for 400 bhp on pump fuel. Boost threshold is similar to a 20G
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Sorry ken, i didnt mean to keep going on about it
. I do want to get it mapped for bigger turbo etc, its just im trying not to push the engine out to the max and end up causing failure, thats the last thing i want. the reason why i was on about the boost figure was that i was wondering would the bigger turbo reach its full potential with the boost im running and would it take longer in the rev range to make full boost, compared to other cars with bigger turbos that are running way higher boost and i dont know if my engine can handle higher boost. I understand what your saying and thanks for all the helpful info
Mark
