Roosie

iTrader: (8)

as a lot of you know im building a engine i have a new t4 but now thinking as my engine is going to be full of modern bits ie seimens,Emerald,7:1 Compression etc im thinking of getting a gt30 for better spool up?

i know this has most likely been posted hundreds of times but oh well

R5FORD

iTrader: (1)

id have the t4 over a gt30..but i prefer the huge punch it will give.i think the gt30 is more progressive.

Porkie

iTrader: (1)

you need to be ALOT more specific.... alot of types of both turbos!

Mike Rainbird

iTrader: (3)

If you are looking at going for the integrally gated version of each, I would go for the roller-bearing T4. As you got your T4 quite cheap, why not pay for it to have this fitted ?

Big Will_

I was pleasantly surprised as to how well the roller bearing T4s on the market now spool up in comparison to standard ones... Certainly wouldn't dismiss one!

Chip

iTrader: (3)

Hmm, tough decision, its as hard as deciding between cassette and dvd

Roosie

iTrader: (8)

how much will it be to convert considering its all new internals on it now and not been run

Mike Rainbird

iTrader: (3)

There will be no significant cost gain to be had with that, so I would recommend selling it (which you should be able to get more than you paid for it) and then buying a roller-bearing version out-right, as you're looking at around Ł650 to convert it.

Roosie

iTrader: (8)

just goto figure out how much after ive got a gt30, modded manifold,ext waistgae, screamer pipe fitted

glancy2081

a voted for the old truck turbo

Mike Rainbird

iTrader: (3)

Prices for those parts are on Martin Hadland's website .

I personally wouldn't run a screamer unless it is being diverted back into the exhaust (more expense ), as it will preclude you from almost every trackday, bar full noise ones.

RWD_cossie_wil

iTrader: (9)

It would be nice to see a well specced engine run a GT30 and a T4 in identical back-to-back tests. Save this post every week ...

Moonstone Steve.

iTrader: (2)

Dont know about well specced but mine will be using T4 and Doug (miller3) is using GT30 on similar spec engines, will be trying to arrange some testing once both are fully mapped.

Steve

Chip

iTrader: (3)

Similar spec doesnt really cut it in the world of definitive answers, but yes Id be interested in the results anyway.

rsdene

iTrader: (1)

MAD uses a gt30 with his 500/500 conversion, nuff said really

Mike Rainbird

iTrader: (3)

AVA uses a roller-bearing T4 in their 500+bhp AT THE WHEELS conversion, nuff said really .

cossie604

iTrader: (2)

BTCC was dominated by Sierra RS500's in the late 80's all running 'standard' T4 turbo's....nuff said

I've gone for the T4 route...basicaly as chip said, its the cassette version of the turbo world, even if it's a little rough around the edges by modern standards its still a damn site tougher than the modern equivilent IMO

steven mc kay

i have had the pleasure of sitting in mikes escort with that t4 and it pulls like fuckin mad .. (starting to forget what it was like mike might need an other run in it some time..)

col cos1

iTrader: (5)

t4 for sure you can always recon it if need be

lawnsy

iTrader: (1)

As above T4 can be rebuilt but the gt30 will be scrap or will cost as much as a new one to replace the core ........

Thats what made me buy a good old T4....

col cos1

iTrader: (5)

mine is now pulling in the figs and not much over a t34 on boost

scoooby slayer

iTrader: (4)

t4s defo reliable on my second t4 cos now. if i went gt would be a 35

dave cos4x4

iTrader: (5)

same as above.

RS LOZWORTH

GT30 all the way

bigchez

No doubt when I get a 500 bhp engine it will be sporting a GT30 and loud as anything screamer. Been in 2 GT30 cars now, 1 cos 1 scoob and the boost comes in hard, but lower down,

Charlie Chalk

iTrader: (1)

Whats the score with T4's? Didn't they stop making them, or they started back now?

And Euans T4 looks like a GT comp housing, do they just use newer parts?

cossie604

iTrader: (2)

wer'nt it just the internal gate housing they couldnt get for a while?? Mines got a turbo dynamics housing on it with the largened penny.

Mr Brannen

Ive been in a 3dr with a screamer pipe and i think it sounded shite,horrible noise IMO,and im normally one for owt like that

Mr C

iTrader: (2)

Is the T4 with roller bearing able to take aMar-M shaft and decent ALS? Is Mikes T4 as above or with a std bearing? Has a GT 30 been able to run decent ALS yet can Mar-m shafts be used in the GT30 or?

I would want to run a GT30 due to what I think are improved spool up times for the same power, anybody got 2x graphs to compare?

Paul_RS

iTrader: (4)

Mark RS off here has one of mikes T4 roller bearing, mar-m shafted turbos and it took abuse well (It's survived my driving on numerous occasions )

Have not done any track days or anything in it, but his car does have antilag and launch control which have been used a lot for entertainment purposes:P

rapidcossie

IMO GT30's have to ran pretty much flat out to get anywhere near 500 bhp.

Red16

It all depends which gt30 (gt3071, gt3037, gt3076, gt3082, etc) varient youre talking about, some will do 470bhp some will do 500bhp some 550bhp, and then theres the whole internal/external wastegate decision to contend with.

Another thing to consider is Martin at Reyland sells gt30's and gt35's brand new for 875 quid

rapidcossie

Which cars with GT30's do 550 bhp?

The last few I have seen from MAD and SCS have just sneaked 500 bhp and thats under optimum condtions on the dyno.

Nash

iTrader: (3)

+ external wastegate and all the gubbins to go with it. The internal gated version of the GT30 costs more than a new T4 when i looked into it, not a massive amount more but it was more.

pete mcrash

iTrader: (1)

when i go 500 bhp.................deffo T4...........

Gary F

iTrader: (1)

Pete good choice, when you going for more power?

Red16

An Evo VI with forged engine, a shearer 3076 kit, piper cams, standard head and valves, autronics ecu NR autosport built and mapped.

made 427bhp @ wheels on corten miller dyno dynamics and then 432bhp @ wheels on APT dyno dynamics.

The gt3082 is slightly larger than the gt3076 so will flow a bit more air, meaning that the magic 550bhp figure is well achievable.

edited to include the graph below... a 2.3 stroked gt3076 Evo



Thats true but with all the extra goodies the price is going to be very similar, but then when it needs a rebuild you just bin it and buy a new one, lol.

speaking of T4's, when can i have a go in yours Gary?

Gary F

iTrader: (1)

Ben im scared to let people have a shot of my car, because if they crashed I'd take my life

Red16

Didnt mean a drive, just a passenger ride will do me

Gary F

iTrader: (1)

Ah ok no bother, actually I've found an auto electriction who's willing to sort my problem, so I should be on full boost soon