gt28 v3071 ??

[pulsarboby]

simple thread
please tell me your thoughts on above turbos, ie best for curcuit use!
i may be in the market for one as it seems mine is kaput again:sad:

bearing in mind car will be on curcuit so i need instant oomph and lots of it at 3k rpm

a few of you have these 3071's fitted now, im not interested in graphs etc or max bhp, just your overall impression of them compared to the gt28, with acceleration, lag and so forth and vfm compared to the gt28
thanks

 

[MarkTurbo]

Never driven a car with a 3071 but after going in Stu's car i was really impressed with the lack of lag, its not really that much laggier than a standard turbo ;-) I wouldnt hesitate to use one on a car that was designed for track use 8)

Suppose it depends what power your after really though???

 

[pulsarboby]

not really interested in the power markie, will probably run it at a safe 1.7 bearing in mind i will be shortshifting a lot! more interested in pickup and spool up times compared to gt28

ive driven stus car and its a snail compared to the beast ive built:lol: lol never wound it up though really, im sure it is quick!

 

[fubar andy]

Would the 2871 not perhaps bridge the gap between them?

What are the main difference between the 2781 and the 28RS?

 

[oap-r]

simple thread
please tell me your thoughts on above turbos, ie best for curcuit use!
i may be in the market for one as it seems mine is kaput again:sad:

bearing in mind car will be on curcuit so i need instant oomph and lots of it at 3k rpm

a few of you have these 3071's fitted now, im not interested in graphs etc or max bhp, just your overall impression of them compared to the gt28, with acceleration, lag and so forth and vfm compared to the gt28
thanks

If it's for circuit use you don't need a responsive turbo or lots of low down torque.You're generally driving in the low gears at high revs not pulling high gears at low revs unless of course you drive like thunder pants :twisted: :lol:

 

[jocster76]

when i bought my new super hybrid gt28/30 i was told it would spool up alot faster then a 3071, dont know if he only said that so i would buy a hybrid

 

[MarkTurbo]

If it's for circuit use you don't need a responsive turbo or lots of low down torque.You're generally driving in the low gears at high revs not pulling high gears at low revs unless of course you drive like thunder pants :twisted: :lol:

Good point, if your driving properly round a track you probably wont ever drop below 4000rpm ;-) Rob take note :lol:

 

[Rishi]

I wouldn't bother running a GT2860 at 1.7bar. Its well out of its efficiency range.

GT2871 - would be a nice quick spooler but as the old man says you won't be in the low rpm so you can afford to go larger. Not sure how much this turbo likes much above 1.5bar. Its proven 390bhp and 345lb.ft before but for a competitive track car i would look for more.

Remember its not the initial spool that matters in this case. Its the responsiveness of the turbo when in the high rpm, heat range, on, off and partial throttle etc...

GT3071 seems to be what everyone goes for these days. Not all for the right reason. Now i know this turbo is very resonsive in its working rev range having been out in Tom's Hiteq car. This will certainly do you well at 1.7bar and will be very responsive out the corners and allow you to control the car more rather than getting a whooping load of boost all at once, throwing you off.. At 1.7bar expect to see 420bhp and 420 - 450lb.ft torque. In its operating boost range its a very good turbo for the GTiR and circuits.

Now to play devils advocate there is also a GT2971 option that Ashills can get you from TD. Its an in between option.

Me personally think the perfect 4x4 circuit/track car would need 500bhp / 500lb/ft. or there abouts. ie. a GT3076R or the quicker spooling HKS GT3037 on a 2L or 2.3L stroker depending on what you want it to do. Have seen 470bhp / 480lb.ft with that setup on another car running 1.8bar and on Super Unleaded.


Rishi

 

[campbellju]

Here's some infomration I posted previously. I used to have a 360deg bearing T28 which is similarish to a 28GT: The point of my previous post was about the restriction in the standard elbow. However, you can see the 2 turbos start to spool up at a similar time but by 4K the 3071 is pulling far stronger (it was running 30% more boost too). If you read the key points its an imperfect test but it does demonstrate there is little disadvantage to the 3071.

My only track experience with the 3071 was very wet so I was fequently at lower revs to not break traction. Because of the large swell of torque from the 3071 between 3 and 5K, it made punching out of corners very easy but still controlled. I think Phil (Bracpan) was toying with the 2971 on a similar thread recently. However, if you really are looking at around 1.7Bar you might just be in 3071 territory again. The 3071 compressor is about optimal between 1.6 and 1.8Bar.


==========================================================
Here is a comparison from my G-Tech 2.0 software taken a year apart but the only major difference being the turbo and the boost level.

Key points:

1. The plots are real world horse power so are the result of everything including wind resistance (2nd gear to minimise) slopes, transmission losses, wheel friction etc.
2. The charts are far from a normalised enviroment but they were done on the same road!
3. The basic engine configuration is the same.
4. The T28 was re-built with 360deg bearings so isn't standard
5. On these occasions, the T28 was at 0.9Bar (Red), the T3071 was at 1.4bar (Black)


http://www.gtiroc.com/forums/attachment.php?attachmentid=402&d=1164020120

 

[pulsarboby]

very interesting points everyone!

jim, it does seem that the 3071 pulls very strong even at 1.4 compared to the 28 especially where i most need the power.....Mmmm!

rishi, wont need 500bhp theres cars running a lot less out there but are still blisteringly quick....i would be happy with 380-400horses i will gain a lot more getting the setup on the car right! suspension etc, as my cornering speed will then be a lot higher, in turn exiting bends at higher speeds on the power! also i can make up a lot by being late on the brakes.

oap-r tis true what your saying.....wont really be dropping below 3.5k revs, so im really after something that pulls strongly from there upto 6k

andy whats this 2871 all about, i know nothing about that?

now you have all really confused me by chucking all these others in the hat:? completely baffled as to what one to go for now:doh:

 

[oap-r]

Go for the biggest possible.
Then you can't go wrong lol

 

[Rishi]

Go for the biggest possible.
Then you can't go wrong lol

Famous last words... :lol:


Rishi

 

[Fusion Ed]

now you have all really confused me by chucking all these others in the hat:? completely baffled as to what one to go for now:doh:

For **** in seat response feeling the 3071 is the best I have seen so far. Your worried about loosing low down response but its improved in every way. I don't think there is any other way to put it than it won't disappoint you. To be honest the stock T28 turbos are poor, any turbo is an improvement.

 

[pulsarboby]

my missus thought she was getting the biggest possible......but she went wrong lol

 

[pulsarboby]

ok ed what housing would be best .64?

 

[Fusion Ed]

I prefer the 0.86. They really are more responsive then you would believe compared to a stock turbo, in _every single way_. They spool sooner, faster and longer at higher pressures than the stock unit. There is no disadvantage to fitting one over the stock or modified stock unit.

 

[stevepudney]

My previous turbo was a TD 2871R (I experimented with the .64 and the .86 ar turbine housing) and I was always pleased with it performance and I managed to achieve an arguable 397 break at 1.7 bar (never a witnessed recording) but having said that I always thought the car pulled very well between 3 & 6000 rpm with less lag than the standard T28.

But as someone never satisfied I upgraded to the 3071R with the .86 ar turbine housing. This turbo spools quicker and harder as far up past the red line as you dare go, I can honestly say as far as lag is concerned it is as close to driving a normally aspirated car as you could get as there is so little lag. As shown in another thread on one of Ed's graphs I had hit 1.7 bar in forth gear before 3000 rpm.

However fashionable it might be, for me it would be the 3071R with the .86 ar turbine housing all the way.

 

[pulsarboby]

think thats gonna have to be the one then chaps, thanks all for your help

 

[oap-r]

For **** in seat response feeling the 3071 is the best I have seen so far. Your worried about loosing low down response but its improved in every way. I don't think there is any other way to put it than it won't disappoint you. To be honest the stock T28 turbos are poor, any turbo is an improvement.

Ed,do you ever recomend any turbo other than the 3071? I've been sniffing about now for a while and the 3071 seems to be mentioned in quite a lot of your responses.

 

[Fazz]

As shown in another thread on one of Ed's graphs I had hit 1.7 bar in forth gear before 3000 rpm.

However fashionable it might be, for me it would be the 3071R with the .86 ar turbine housing all the way.

It was this and other reports that decided it for me and this is exactly what i got!

hoping to show similar results as steve in terms of spool up and power when i'm set up and mapped...

steve - get on the dyno!!! gotta be 430bhp anyway.....??