Current setup is a GT2871R, Pro Alloy FMIC, PRV, K&N panel A/F, 2.75" straight through decat zorst from turbo-back, Walbro 255 FP.

1st runs will be with the original Novitec @ 1bar
2nd runs with Gtec 2 HF @ up to 1.4bar.

What power do you reckon I'll make? 900Bhp?

I'll be happy at around 340Bhp 300lb/ft, but may turn the boost down. Restrictions are the A/F and zorst diameter I reckon.

I dont think a 2.75" turbo back decat is restrictive.

I think you'd get the biggest improvements with a straight induction and a decent EBC though

What rpm do you hit max boost?

i'd be interested to see this graph as I may be going for the 2871R but would have a few more mods and would like to see when it spools etc! what housing have you got?

EBC would have been a good addition!

also, are you keeping the standard rev limit as I guess the power curve will still be rising? i'm you will be with standard internals.

.64 housing and it spools fully by anout 3.8krpm.

Oh yeah internals are std so I won't be pushing any more than 1.4bar I reckon (1.5bar on overboost is an absolute acceptable max to me).

AVCR is the next stop for sure. I'll no doubt be losing the max out of the car as the boost will always tail off towards the end, and it's the time after getting on boost, not how far up the rev range you are. e.g. floor it at 4Krpm and it will hit 1bar and tail off to 0.8 @ redline, but floor it at 5.5krpm and it will hit 1bar but tail off to 0.9bar at the redline... Just a feature the PRV and actuator, imo and ime.

so if you floor it at 1500 rpm when does it hit 1 bar?

3.7-3.9Krpm.

mid range doesn't really matter too much, its how much boost you have at redline. mine used to hold 1.25 when using 1.5 midrange. i would keep it under 1.2bar though IMO.

mid range matters to me, as I dont want to be driving around in 1st

I think I'll stick to my small turbos which give me 1.2 bar from 2300rpm to 5500 rpm

i meant with standard internals. its not the mid range boost that does the damage but how much you have at redline

1.2 bar at redline could produce 360bhp on that turbo with around 320lb/ft.

Ross

Really?! You reckon?! Ow! What do you think 1bar would make as I put that at 280-300 depending on other mods - the boost I had been running for a while?

Maybe not 1.4bar then! We'll see what happens when it's on the rollers.

i would put safety first in this situation! I'm sure Perfect Touch will keep this in mind though.

Well its all about having correct fuelling.

1.4 midrange and 1.2 redline is gonna be around that kinda figure. 1 bar across the range is gonna be around 270-280lb/ft and probably 300-320ish?

Its hard to tell as there has been only HIGH powered GT2871r's really.

Ross

As a side note, i doubt you will be anywhere near those figures. Torque will be down as i reckon it will be overfuelling and bhp will be lower due to lack of holding boost.

Ross

330bhp before you run out of fuel from the standard injectors.....

I think about 290 torque and 315/320bhp

Ben

Will you Livemap it?

Good luck and enjoy Rob's test drive

rob does like his test drives he told me he had to pull over for one bloke to be sick after drifting his skyline around a roundabout

PMSL

I don't think Welformed is having it mapped just a couple of power runs with different chips.

Well he's not replied... wonder whats happened...

Ross

...It's blown up...

Come on WF, want to hear how you got on

Sorry chaps, been too busy playing around with my toy to post on here. Save it for when I'm bored at work.

Right well, good and bad news.

Good news is that we got as much out of the car as possible and it's fuelling and running fine on the current setup. Bad news is I forgot Barbz had installed a 1 bar actuator on the turbo so I could run it with a std SMIC and Novitec. Either that or… he didn’t put a GT2871R in and more something like a GT28R/RS, which couldn't be surely? Rob, the guy at PT was confused. It was spooling like a GT2871R at around 4Krpm but only producing the power and torque of a smaller turbo.

What I don't get is that we/I can get the turbo to overboost to about 1.4bar, but it will steadily tail off to about 1.2bar. That suggests smaller turbo struggling to supply the air as the revs rise or maybe this weaker actuator is failing to hold boost and it tries to tail off to 1bar? I need to get the turbo off to identify it and the actuator. How can you tell? So a tad confused atm until more is done. Don’t suppose you can just buy GT2871R actuators separately and install? Also the std Airbox was restricting airflow costing 12bhp

Anyway, at 1.4bar and 1.2 to the redline on my gauge, it was making 301Bhp and 270lb/ft, from only 270Bhp and 230lb/ft. Suspect figures. This really doesn't explain on road performance at all. Put it this way, I had a play with an M3 the next day at 1.3bar. He got a good 1 second jump from 50 and pulled away a couple of car lengths from about 1 by 70. Come 4th gear I was slowly sailing by… Before the RR, assuming I had the lowly 270Bhp figure, I have matched M3's from 30 to 120 or they inch away, depending on who got the jump. So definitely faster. Much faster. 1.3bar according to PT is about 280Bhp max ( -12bhp for airbox, -about 10bhp? for the 0.1bar of boost less). Can you comfortably cruise past a top-up convertible E46 M3 giving away 63Bhp and a lot of torque? Oh and he was definitely trying - you can clearly see the double kickdown of his auto 'box and the hard auto changes into 3rd and 4th gears on the vid...

Adjust PT figures about 20 and it seems to make a bit more sense.

Also, wasn't that impressed with the service there. After clearly arranging what I wanted to do beforehand and confirming this before I set off - see power on current chip, then install new chip and run, then up the boost on that - PT didn’t seem at all keen even to put my car on the rollers! I had to verbally fight, plead and reason to get the to do what I asked. WTF? Even then they refused to change the chip over and do a run on that at all. "But this is what I had just driven 80 miles to get done, mate". I got the impression that it was a Sat and they just wanted to play with their own cars than deal with a customer. (btw, I had a sneaky check of their "very busy" saturday diary when they left me alone in the office for a moment. My booking was on the only entry for the whole day...) Once the first run was done though they seemed to be ok and settled into the work. Don't think I'll be going there again other than for the expertise feedback.

Northampton Motorsport was a whole much more enjoyable experience. PT was more like being their for the birth of your kid, but not being allowed into the delivery room, then they tell you the kid was ginger...

Pics of graphs to come when I get round to uploading them!

Did they check the charge temps ?

If barbz fitted a 1 bar actuator, the turbo would be able to hold boost better. Not the other way around.

There aint a lot more to say other than lets see the graph.

Ross

That's what I thought. I'd expect it to hit 1 bar and stay there. Maybe the 1 bar actuator is just an old temporary weak one? I've seen that before, if the diaphram isn't great, boost seems to bleed off. But surely Barbz wouldn't rip me off???

I need to see a graph of a GT28R/RS/RSR with similar mods to compare.

They didn't check the charge temps other than listening for pinking on the road. It was ok up to 1.5bar.

I think most people with those mods would normally have an EBC, I would say it will help quite a bit.

You definately have a GT2871R 0.64 turbo, I have seen it in the flesh The 1 bar actuator should ensure it doesn't go below that and by the sounds of it you are running 1.2bar at redline. You would expect a little pressure drop off i.e. 0.1-0.2bar by redline when running a PRV and you also have restrictions elsewhere like the airbox. Do you also use a v-band adapter for the downpipe?

If you can open up the induction and use an EBC then I would be confident in seeing 320bhp & 290lbs/ft.