lockie

My mate just bought a Saff with 402 bhp but it's very laggy
Spec is
200 block mahle Pistons
4wd head/standard cams
4wd inlet
Turbo technics t38.63
Light blues
All the normal exhaust/3bar/500 cooler etc

Doesn't seem to one on full boost till 4-4.5k rpm

Well I ended up melting it on the way home (no4)
Will a bd14 inlet cam help with the lag or make it worse?

I take it bd10/s are no good for this spec?

Loomer

That turbo is quite lathargic, but it doesn't sound like it was well set up, so properly tuned it might be a bit better than it was, but if your after a dramatic change in spool then the tt38 isn't really the turbo for you

James Porter

iTrader: (1)

That's a big turbo so the right cams & boost will play a part in getting it to spoil up quicker.

vroooom ptssssh

What do you want? power or driveability?
theres a few ways you can get round it:

Roller bearing core
Smaller exhaust housing (or turbo)
if you're on standard cams then you'd need to have a smaller lobe to make more power low down which defeats the purpose of having a big turbo..
ALS

tony66

iTrader: (7)

just the nature of the turbo tbh a tad laggy,you can check the basics-actuator preload,wastegate flap seating/condition, boost leak check inc dump valve if fitted... a physcal check of the turbo wouldnt go amiss either

AJC

iTrader: (6)

It's because it's got a T38, they're shit

seriously, a T34 will do 400BHP, just run out of puff towards top of the rev range, i have honestly never been in a car with a T38 and liked it, i have always thought them to be crap.

If you've got the money, get a twin scroll turbo slapped on it, with regards to model i couldn't recommend any particular one, but if you don.t want to spend the money, T34.63 ans siemens 55lb. Perfect combination and will see 380bhp and i can guarantee it'll be better than the T38 piece of poop.

lockie

It's my mates car & tbh he is just gonna use it for the summer & maybe sell it

Just while the engines in bits I was wondering if I should change a cam to help

It will go get set up when built

I had an rs turbo 4wd Cosworth with a t38 & it was awesome but had different cams, head work etc

sierrafun

higher compression ratio and smaller interccoler .the rs500 is large .and the t38 is laggy turbo better t34

ajamesc

why on earth would you fit a smaller intercooler to a car with 400bhp. On a hot sunny day with high charge air temp you will loose loads of power lol

sierrafun

from engenering place .every stage hp have the right itercooler not bigger not smaller .there are maths that calculate the right size for the intercooler and the capacity measures in cfm .the rs 500 is large for the stage 400hp .is made for rs500 and 500 + hp ..we made a test years ago in 400hp 4x4 with pro alloy coller ..the car was lagy and we tryied with smaller cooler half size and the car was much better also the tubes 3 inches are very big need smaller ..the cams was big bd16 bd 14 we fit other smaller and we made higher cr .the result was better

ajamesc

I guess that depends who you listen to everyone has a view. I was advised to fit a 500 style cooler when I went to 350bhp. And the charge temp still got hot in the summer so I had ecu controlled water injection as well

cossynut2

Why have you got such a low opinion of the T38 ? I have one with a billet compressor wheel and with all the other mods I have made it is superb! Lack of lag and quick spool up is what mine delivers. Its like anything you do, you have to have all the right stuff to get the best out of it. I can guarantee you would be impressed if you came out in mine.

Loomer

Is that a TT38 though? Don't forget there are differing types of 38 the smaller variant that looks externally like a T34 is not as laggy as the TT38 which is almost T4 size

throttle jockey

I think it depends weather you have it mapped right nothing wrong with laggy turbos if mapped correct then it's down to the driver if you know how to pilot then I'd run an old t4 against any new stuff it's all nonsense these days if you have a specked engine by a reputable builder then it works home built guess work is a waste of time been there done that.its ok to self guess a stage 3 spec anything above in my opinion is specialist job or it youwill never get best out of what you have

ajamesc

To be fair it's silly comparing a t4 to a modern set up. It physically can not process as much air or as quickly

AJC

iTrader: (6)

I'll have to give you a shout when i'm next in southampton!

My mate had a 4wd on a T38, imo it had the lag of a T4 and the pull of a T34, so was shit.

2wd cos, T38 fitted, really didn't impress me at all. It may just be me with the odd bad experience of them

Staffi

iTrader: (1)

My old Saff G88 had a UT T38 on it and it was a dog of a turbo, pulled well top end after Karl had mapped it but very lethargic, I think the TT T38 however is a different animal.

R4N SS

iTrader: (6)

My car with a gt30 0.63 was laggy as hell - full boost at 4.5k - hated it. In a way glad it blew up

throttle jockey

Not sure I agree with you tbh,if your engine is speced right the t4 will see most off Mike rainbirds car is a good example t4 right spec good pilot =see what I mean I have a well spec t4 car as well not quite mikes spec and nothing cosworth wise yet to impress me and yes I've had a play with these twin scroll jobby and I wasn't stunned beyond belief thing is James you can have all the power in the world,makes no sensse all the rolling roads graphs it's all talk,a speced engine done right with any turbo combining revving to 8500 is a weapon especially when it's a chunky old t4 lol...

Staffi

iTrader: (1)

A turbo change would have been cheaper Ran

R4N SS

iTrader: (6)

I know but that was the easy option

cossie4i+

iTrader: (15)

Not saying anything lol


Steve

sierrafun

what about t36 and the 420 max power of it.. is it not so lagy like the t38

Mark Shead

It's not a good combo and can be surgy but it's cheap so good

Mark

sierrafun

garrett 2871 as well great turbo ball bearing

DAN400

iTrader: (3)

obviously the car needs a good setting up/map
nothing wrong with a tt t38 ,
very good turbo imo for its age,
its old hat now but still does the job

tony66

iTrader: (7)

lag was part of the fun with a cossie-nothing nothing-oh ya fooker! as it snakes up the road...if you want zero lag put a 335d in it-boost from idle lol

cossynut2

My t38 with billet compressor was built by Vince at CR turbos and works really well on my 2wd. The most usual comment from anyone that has been out with me is " fucking hell this is an animal"

Staffi

iTrader: (1)

What power levels has yours made?? Mine made 447 bhp but torque was rubbish at 378 due to wrongly being spec'd.

Flamed well though

sierrafun

some 480hp in high boost

sierrafun

t38 is look like and very similar to t3 t4 garertt stage 3 for 500hp max with A/R 60 front

Rod-Tarry

I agree with him. Your knowledge of 2015 Turbo technology must be very limited. MikeR was in his pomp 15 years ago his T4 car would be totally destroyed by a modern EFR twin scroll set-up running comp ratios thought impossible back then. Its all talk is it because we have more Power & quicker spool now than those old Touring car Spec cars. You simply are years behind with your thinking & until you are shown the difference you will believe it. Mike would find it funny that you hold his old banger in such esteem.

R4N SS

iTrader: (6)

my next cossie turbo will be a borg warner version - but then again by the time i get my finger things would have moved further along

ajamesc

That statement it rubbish to be fair mate. You talk about a good pilot which is an important part I'll agree if the driver can use the gears and revs and keep the car on boost it makes a difference. But what if the modern set up car has a good driver? It makes far more power and torque lower down in the rev range and holds it for a longer rev range? Coupled with good tyres and a good suspension set up there's is absolutely no comparison. If you went in a modern technology 650bhp road car your opinion would be changed in less than 15 minutes

cossynut2

ajamesc. Would you say a 2014 540 bhp twin turbo Porsche 911 has modern technology?
I have told this before but my 2wd Saff with its "old fashioned T38 etc" had a race with one and it was on a nice long stretch of dual carriageway. from 50mph up to silly speed it could not pull away from me and when the guy was turning off a few miles on he pulled over onto the hard shoulder, put his window down and shouted across to me,"fuck me what have you got under the bonnet of that, I have never had any car that can keep up with me" He was going to the Porsche owners day at Beaulieu Motor Museum and I wondered if he told any of his mates that an old 1990 Sapphire Cosworth was as quick as his Ł98000 Porsche! I must admit I was in a bit of shock myself as I thought it would have left me for dead!

ajamesc

It's a silly argument i have a friend with a 56 reg Porsche turbo and it's a phenomenal car. Yes I may of been able to hang onto the back of it with my 500bhp gt30 set up but in the real would on a twisty road he would leave me for dead. There's no denying any car with 400+ bhp isn't going to be fast weather it has a t4 a gt30 or a t38. But how it makes that power has changed that's fact. Many people may say these new turbos are not all this or they have even tried them and don't rate them. Get a well built spec'ed and mapped engine from a tunner who dose know what he is doing and the difference is night and day

PF Ben

iTrader: (1)

...........

turbotrev

Why did you hate it so much?
Cos of the lag?
Why not just keep it revving in its powerband?

Cheers Paul

turbotrev

Nice to see opinions from both sides here.....
Could get messy though....

Cheers Paul

cossie4i+

iTrader: (15)

All I will say is engine spec with a TT T38 makes a big difference.


Steve