isnt a bit of back pressure needed for a turbo?
My 200mph budget build
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isnt a bit of back pressure needed for a turbo?
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no, any forced induction engine wants the least amount of backpressure you can get away with.
look at drag cars for example, just manifolds and thats it.
back pressure can help certain N/A cars, though a lot of n/a engines can be tuned to not need backpressure and benefit as a result
look at drag cars for example, just manifolds and thats it.
back pressure can help certain N/A cars, though a lot of n/a engines can be tuned to not need backpressure and benefit as a result
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hows yours coming along anyway, all sorted now?
Soldato
Which ones.
Its another myth in my opinion. Oversize exhaust causes backpressure which I think this myth comes from, to large area = slow gas = no column inertia and the gas flow stalls.
Outside the scope of this thread I guess though.
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yes your right, when i said certain cars i meant stock or close to stock engines, if you increase the size of an exhaust to large and you dont have an engine specced to match that sort of flow you can loose power, pretty much what you said only you worded it better and i forgot to explain it further
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the real greddy ones are stupidly daft for cost, something close to £200 i think, since its only a piece of metal then you are just paying for the name.
Bit like my intercooler, its a trust GTR replica, i paid £72 new, they are about £1000 from trust and the replicas has been run on massive power engines before.
the only reason i bought one is it makes piping a lot easier instead of trying to cut and plastic weld my original elbow.
Will be dropping my intercooler off next week with the fab company to modify to fit in my engine bay, id imagine they will have it for a couple of weeks but i dont mind as ive got to MOT and Tax the car at the end of the month to pay for
Bit like my intercooler, its a trust GTR replica, i paid £72 new, they are about £1000 from trust and the replicas has been run on massive power engines before.
the only reason i bought one is it makes piping a lot easier instead of trying to cut and plastic weld my original elbow.
Will be dropping my intercooler off next week with the fab company to modify to fit in my engine bay, id imagine they will have it for a couple of weeks but i dont mind as ive got to MOT and Tax the car at the end of the month to pay for
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well tonight i have been busy on my ebay elbow.
firstly i cut the smaller diameter off, i could have done it after the lip and it would have been simpler but hindsight is a wonderful thing!
after cutting the end off i used a dremel to enlarge it back out to the correct size, not sure neat but not to bad, stops the restriction in my pipe work by making it 70mm internal diameter instead of 60mm
i then used my grinding bits to take out all the bumps, casting marks and general crappyness, it still looks rough in the pictures but feels silky smooth.
this took me 2hrs to do in total and its not a fun job sitting in the kitchen working on it, got pins and needles in my hand now!
firstly i cut the smaller diameter off, i could have done it after the lip and it would have been simpler but hindsight is a wonderful thing!
after cutting the end off i used a dremel to enlarge it back out to the correct size, not sure neat but not to bad, stops the restriction in my pipe work by making it 70mm internal diameter instead of 60mm
i then used my grinding bits to take out all the bumps, casting marks and general crappyness, it still looks rough in the pictures but feels silky smooth.
this took me 2hrs to do in total and its not a fun job sitting in the kitchen working on it, got pins and needles in my hand now!
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got myself a decat pipe for my birthday this year, even with the big turbo ill be running a 3inch exhaust on the road as due to running low boost there wont be massive back pressure issues and it keeps the noise down to semi-sensible levels........to say its loud compared to when it had a CAT on it is a bit of an understatement!!
When i started it up i crapped my pants, thought the decat had fell off, my neighbours werent to impressed!
Though its much better from 7-8krpm now as the ports where being heavily restricted by the CAT.
Big difference in weight
new gaskets and bolts which is nice
checked flanges and they are both true and flat
had to jack the decat up so i could get the lower brace back on, but all bolted up!!
video of starting it up
http://www.youtube.com/watch?v=0oiKRYFv2I8
When i started it up i crapped my pants, thought the decat had fell off, my neighbours werent to impressed!
Though its much better from 7-8krpm now as the ports where being heavily restricted by the CAT.
Big difference in weight
new gaskets and bolts which is nice
checked flanges and they are both true and flat
had to jack the decat up so i could get the lower brace back on, but all bolted up!!
video of starting it up
http://www.youtube.com/watch?v=0oiKRYFv2I8
Soldato
Sounds like a V8 
Soldato
Sounds like a boat!
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thats what they sound like with big ports, very rough sounding as its got massive overlap, on stop ports they are a lot quieter and smoother sound
stock car with decat is about 106db, mine is probably closer to 110db
stock car with decat is about 106db, mine is probably closer to 110db
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http://www.youtube.com/watch?v=pzRRHov_KUY
took a little bit of fueling out at idle and seems to calm it down slightly
took a little bit of fueling out at idle and seems to calm it down slightly
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updates ???
really enjoyed this thread
really enjoyed this thread
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I couldnt be arsed to read every page of this thread cos im lazy, but i would say a big jaguar xj12, wich i believe they made a forged engine version of so u will have a very strong block, nos is a must for instant bhp gains and a nitro-meth kit. and try and squeeze as much torque out of the engine, its not the bhp so much that u have to worry bout. I would use an aem standalone ecu and find a very good tuner, advanced motorsport at silverstone are excellent. A twin turbo or supercharged application and setup would be needed, due to the distance i would opt for the turbos, twin t40 hybrids should give u plenty of ooomph. U also need to look at if it is to be road legal or for track use only, this will have a large impact on ur modifications, strip as much weight from the front but u will need it in the rear to give u the grip.
Great way to make a car fly
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