Looking for some advice for the best turbo for upto 420 bhp giving the best responce with my spec.

I was planning on running a T34.55 to save the gearbox but I now have a straight cut box so can go a bit wilder on power.

Engine spec is

7.2:1 comp
ported head
mls gasket
long studded
BD14 inlet cam
55lb blacks
4wd inlet

 

Should of said I want to stay internal gated and ideally keep the 4wd manifold.

 

RB T38

 

As Aaron says, or the 3071 will do the job...

T34.63 would be on it's knees at that power (if it'd make that is) but wouldn't be for long..

 

good for 420+ 2871.. ball bearing always use for low lag .also 3071 ..also at t35 you can put morram shaft and go for 2.5 boost .cost is big..what ecu you have ?

 

Why do you want to keep the 4wd manifold?

Its far inferior for performance

 

Chip, just a quickie and sorry to hi-jack your thread Neil..

What max -ISH power can be made by the 2wd Manifold??

 

For around the 400bhp mark i'd go GT2871R or for the 450bhp mark i'd go GTX3071R - that will give similar repsonse but have headroom in it later on to go for nearer 500bhp with an injector change.

 

Wots wrong with a good old gt30

 

Never personally tested it, but I know of a couple of cars that made it to around 600bhp on it.

Not sure I would want to go quite that far myself though.

 

i know gt3582 for 600 in yb engine check this out internal as you wish 2 bar boost 420 + http://cgi.ebay.co.uk/Garrett-Turbo-...item1e5a54d10c

 

Main reason chip is ease of fitment as far as heatshields and exhausts. Im not chasing power really and would be happy with 420 which shouldn't be at the limit of the 4wd manifold. The main reason I'm thinking of a new turbo is the car will need a remap when the cam gets changed so might aswell do all the changes at once.

 

You would also benefit from bigger injectors, safety margin.

Steve

 

why is the 4wd manifold not as good for performance? My engine runs it at 450hp

 

Really Chip?? i always thought they were pretty dead after 400bhp...

Aaron, i think it is good for performance mate, as i've just said when quoting Chip, i always thought 400 ish was the limit of the 2wd one hence why i asked the question....

 

It doesnt flow as well.

 

Are you talking about inlet or exhaust manifold postie ?, because Chip has answered for exhaust.

Steve

 

God no mate, the rwd one is capable of pretty massive power really.
Porkie was on one at 600bhp for example.

Ade was just over that although had problems with the middle two cylinders caused by the lump on entry to the manifold we believe which hinders flow on those cylinders.

 

Yes mate, I meant the exhaust, apologies if that wasnt what was being asked

 

Arr, good spot Steve, wires crossed Chipa, yes i was referring to INLET fellas...

 

in the 2 wd exaust manifold can you put external wastegate 46mm to go for 600 hp ?

 

Yes you can, martin at reyland has done a few.

 

Yeah 400ish seems to be about it.

Small turbo escos is the best of the bunch (barring the mega rare 500 ones)

 

gt30 for me.

 

With good mapping would a smaller GT30 be as responsive as a T34?

 

GT30 all day!

 

Yes it will match it upto 4000rpm and give you another 100hp above!!

 

Well that gives me something to think about over the next few weeks, its just a shame there isnt many different spec cars up here in Scotland to get a run in before deciding. Will try and get a run in Kevs RBT38 car as that would be the easyest bolt on and go option.

 

No sweat Neil,needs mapped first though.

 

Well you have 3 weeks Kev chop chop

 

Have you considered the EFR-series from B&W ?
EFR-7064 would be good on these power levels
http://www.full-race.com/articles/bo...fr-turbos.html

 

Well the road tax in May is a start lol.

 

think u should worring about your gearbox at 420 its gonna shit it self

 

for me it would be cossierich spec, i think thats his name with the gt30 on stock port head awesome road engine imo.

 

Neil has a big tooth box mate.

 

GT30 would kill a T38 with the right inlet and cam

 

Im happy with my spec , 480bhp and 485lb/ft @2.1bar

Steve

 

Not saying you're not. But getting back to the original topic, if you had the chance to choose a turbo again, same prices etc etc - T38 or GT30 then?

 

Why change when my spec does the job ?

Steve

 

hows the t38 for surge ? can you run 2.1 bar straight up with no surgeing low down ?

my old t4 used to surge its tits off on standard port head with bd14s, had to be caped to this