Sonic Boom

iTrader: (11)

I'm doing it on the 24th of March you should come along.
Rich

scoooby slayer

iTrader: (4)

ive been reading up on gtroc about it id need to get my passport sorted as it appears they need it for entry to marham, mine ran out years ago lol
can anyone spectate or is it just extra passengers ?

stevieturbo

All spectators must be passengers, and they also need security clearance.

It isnt a spectator event.

scoooby slayer

iTrader: (4)

well the hunt for 700+whp again has begun
i want to get abit closer to the power the supra had.
my manifold is layed out in twin scroll but it doesnt have equal length runners and it only has 1 wastegate that joins both sides just below the t4 flange so not true twin scroll but i think i am going to try it as the gt40 was spooling well even with the manifold blowing badly so it can only get better my dyno graph shows 1 bar by 4200 rpm.

after reading mad ades thread about these borg warner turbos i am going to treat myself to an efr 9180 with a t4 1.05 a/r external wastegate turbine housing. i have had a quick measure and im sure the turbo will sit on my manifold ok and not foul anywhere, i can just mod my downpipe to suit if necasary and my oil and water lines.
i am hopeful it will spool like my gt40 does on its 0.84 a/r housing but make 100+ whp more up top at around 1.5 bar and a bit more torque aswell, and pick up better after shifting.

ive just gotta find one now as stocks seem very limited.

cossie4i+

iTrader: (15)

It never ends

Steve

3dr

iTrader: (1)

Scooby slayer love your level of motivation.

I'm currently building my rb26 engine (forged).
I would like to go single turbo set up and sell my hks 2540's to help fund.

What's best to go for, aiming for 650-750bhp

scoooby slayer

iTrader: (4)

well my r33 is a forged 2.7 running a gt4094r with the smallest exhaust housing they do so it is limiting the top end power but giving best spool for the turbo.
at all 4 hubs its makeing 590 hp, so about 660 flywheel hp, 475 lb ft flywheel. 1 bar of boost 4250 rpm, and the full 1.5 - 1.6 bar by 4600 rpm.
but if i was you id be looking at the new bw efr series maybe the 8374 or what im going for the t4 twin scroll 9180.

scoooby slayer

iTrader: (4)

welll i took the old girl for mot yesterday afternoon straight through no advisorys.
il tax it 1st of march.
i went for a quick run before i came home as i havnt driven it since refitting the manifold now its all done properly, so i did a few runs in 3rd gear and i hit 0.5 bar boost at exactly 3500 rpm and all in 1.5 bar by roughly 4600 rpm its hard to say exactly as once the boost passes 0.5 bar the revs rise so quickly its a job to watch it tbh.
so with no alterations to the boost controller ive gone from holding 1.3 bar in 4th gear to holding 1.5 bar in 3rd gear, 4th gear should now see nearer 1.6 bar id of thought with the extra load of the taller gear.
response is vastly improved aswell the manifold leak was far worse than i had realised tbh and with me running the small exhaust housing there must be alot of back pressure in the manifold trying to get out anywhere it can.
im in no rush to change to an efr9180 now as it feels so much better now im not sure it needs it, im gonna just use it as is now for a while and see how i go.
il get the racelogic out soon and see how things have imrpoved with the extra boost and response.
happy days

scoooby slayer

iTrader: (4)

well the max i can see in any gear is 1.5 bar, it is responsive for such a big turbo but still only running 650 hp from a gt40 seems pointless when a gt35 should do that, so ive ordered this and it came today.






a 1.06 exhaust housing as i think my 0.85 a/r ts housing is causing a restriction, im hopeing once mapped i will be able to run nearer 2 bar boost with the new housing
the car has (apparantly) run 875 hp in japan so im hopeing the engine has some more to give.

robw

have you got the billet turbo or non billet?

scoooby slayer

iTrader: (4)

non billet, it was purchased august 2008 by previous owner but has only done 4000 miles since at max 1.5 bar.

i think the 1.6 bar on the dynapack run is just due to being run at more load than i can make on the road.

robw

soon be time for that performance box to get used

scoooby slayer

iTrader: (4)

will it ever dry up ffs lol

the new housing isnt going on straight away i want a little use out of it first, with the v box and some pod

robw

good comparison for the turbos too

turnover

Same housing I had on the ybt will make more power higher up the revs mine was capped at 8800 rpm but was still pulling on the graph but was only 2litre,yours will make shit loads more torque with more boost but obviously you may loose 500 to 700 rpm before it hits full boost

scoooby slayer

iTrader: (4)

tbh i hadnt thought of that, il make sure i get some perfect runs in with the v box before i switch the housing out and remap.


excellent thats nice to know mate, i dont really wana go beyond 8000 rpm but even so im currently making 1 bar by 4250 rpm and 1.5 bar 4600 rpm so if i end up with 5000 - 8000 rpm useable power band i can live with that.

it is quite strange at the moment it is super responsive and comes on boost but although the boost is there it doesnt seem to pull then i feel it pull again at around 5000 rpm, i think with the 0.85 a/r housing its almost trying to boost to soon and the engine cant use all the air, i think if it didnt have the anti surge housing it would be surgeing tbh.
although i love the responsiveness im running a gt4094R at 650 hp which seems pointless i could have a gt35 doing that i should be nearer 750 hp hopefully.

the 0.85 a/r twin scroll on my 2700cc six pot i think is a big restriction and hindering the top end power and the ammount of boost i can run.
just from my exhaust leaks ive gained 0.2 bar of boost and the leaks wernt massive it says to me theres a hell of a lot of back pressure in the manifold.

mark shead said to me the 1.06 a/r housing was the one to go for with my turbo so i bought one, she should be manic at 2 bar boost hopefully

where did you make full boost on a 1.06 a/r mate ?

turnover

Never had a single setup on my r34 gtr had twin hks but was a 2.8 hks motor ,still used to pull to 8000rpm where the limiter was set,and the best It ran was 11.3

scoooby slayer

iTrader: (4)

on your mk2 escort yb engine mate just wondered where the yb on a 1.06 housing made full boost ?

turnover

About 5200 but with large cams and race fuel

scoooby slayer

iTrader: (4)

ive found these on ebay

http://www.ebay.co.uk/itm/Snail-Turb...item1e7867fa10

thats for a gt3582r but they do sell one for my turbo for about Ł220, i wonder if there any good and how much id gain ? is it just the comp wheel thats different on the gtx turbos do you know ? do they add spool time for more power ?

im only on 99 fuel and not sure on exact head/cams spec, if i could get full boost by 5200 rpm on my 2700cc id be happy with that.

J1mbo

iTrader: (1)

What makes these so laggy? We've just done a Porsche 944 2700cc and it has 500lbft (thants not peak) at 3500 rpm and 680bhp on pump at 7500 surely the big capacity is a massive gain over us boys playing with piddly ybs I'd be aiming for 4-8k rpm rev range 5200-8000

scoooby slayer

iTrader: (4)

ive got a big power band now and it is responsive to be fair, my missus even commented as it feels similar to my small twins rb26 r32 gtr but im looking to run nearer 750 hp which i will have to trade some response for with the gt4094r.

is the porsche on a gt4094r jimbo ? and if thats on your engine dyno aswell its not really comparable as the engine is under more load isnt it ?
how is the load calculated on an engine dyno ?

i have the exact ramp time data for my dyno plot on the 0.84 a/r housing.
im currently makeing 654 bhp at 7500 rpm and boost at that point was 1.5 bar. right in the middle of the curve at 4500 rpm 300 hub power, 400 lbft. the ramp rate was set at 300 rpm per second.
i dont want to even try to run more boost with my housing as im sure the little twin scroll 0.85 a/r housing is on its knees already.
have you seen any engines on your dyno with a twin scroll 0.85 ar housing by any chance mate ?

im hopeing with the bigger housing i can run around 2 bar of boost, hopefully gaining 100 lbft and 100 hp, either way with a more freely flowing turbo and 7 psi more boost its gotta make more power, its running twin fuel pumps and 1000cc injectors so ive got plenty of fuelling scope left and its been converted to map sensor seen 1.7 bar peak on dyno plot so should be a 3 bar map in there aswell.

turnover

jimbo the skylines aren't normally laggy but the ones I've allways had have been on twins so spool was fantastic as you say so was the torque,my escort was laggy but was on a 1.06 ex housing so power range was 5200 to 8800 ,but obviously not user friendly round the town,must of had a descent size turbo on the 944,sounds a good result though

J1mbo

iTrader: (1)

The porsche was run on lots of different turbos from one off made to a straight forward t04z which is 72lb air and we only ran 1.9bar

The t04z is a very close match for the gt40

And that was a first attempt with what cams we were given, anyway power output wasn't my aim I just wanted to see why in general the single turbo skylines never seem to work down the bottom,

J1mbo

iTrader: (1)

I know the escort was built for purpose so can understand why it has a top endy power band but the skyline with 700cc more is similar power band it's surprising

stevieturbo

The latest "billet" turbos use different compressor wheels as well as lighter and more efficient turbine wheels.
Although obviously depending on who built it or what spec, it could be a combination of all sorts.
I'm sure there are some turbos out there still using the old turbine wheels but with new billet compressor wheels.

An example of Precisions older turbine vs their newer stuff. The new wheel being much lighter.

scoooby slayer

iTrader: (4)

rb26 do seem to lack in torque when compared to say a 2jz, but they are a short stroke engine that loves to be revved.

do you know what housing the porsche was on mate ?

scoooby slayer

iTrader: (4)

it has got me wondering mate as im getting it mapped again anyways if i should stick a modern comp wheel in there while the turbo is off.
the snail advertised wheels seem to be a drop in replacement im just gonna look around and see what the gains/losses are.

stevieturbo

The Snail wheels do look like a possibility, but then the unit will need balanced etc and of course you need to find someone happy enough to fit the wheels which have nothing to do with them ( read warranty and customer backlash if things go wrong )

How much actual technical engineering is in their wheels as opposed to others, Ive no idea. Are they just mirroring cast wheels on their CNC ? material quality etc ?

I actually inquired with them about making a new wheel for my supercharger. But they were a very new seller on egay then, and the thought of sending my parts to Taiwan, was just a bit too risky. But of all the places I emailed, they were by far the most helpful.

Extreme Tuners in Greece seem to have a huge range, although despite saying they could make me one...when it actually came to pricing or lead times, they stopped emailing.

J1mbo

iTrader: (1)

.82 with a -10 psi of back pressure over boost so more than acceptable

turnover

I take it this was on engine dyno mate as sounds a lot of power on .82 housing on pump fuel and 1.9 bar?

Brendan

iTrader: (1)

you said "if only nissan had used cat studs 3/8 unc they would never snap there tough old bolts"

well we had so many problems when removing the exhaust manifold on my toy we decided to replace them with items that would resist corrosion much better! we thought about going all titanium but would have had problems with the titanium studs so went for a more corrosion resistant steel and high temp titanium locking nuts. It is worth the aggravation!

J1mbo

iTrader: (1)

Yes bench dyno, five inch exhaust 15deg ign

For a comparison at 2.05 bar big valve 2.2yb on pump give 711 so the Porsche is even to the yb there abouts except it's 500cc up so not quite as efficient

Why does it sound alot, that turbo on race fuel can show 780/790 at 34psi

Ps I'll get the exact figure from tim as I'm going by memory

Pps the .82 exhaust housing is obviously more than capable and suited to the exhaust wheel to be 10psi down on back pressure in relation to boost

turnover

I was referring as if it was on a dyno,it would be somewhere around the 570 hp mark with a 15percent loss,and the figures you said I thought it must be on an engine dyno

scoooby slayer

iTrader: (4)

was that open scroll or twin scroll ?

scoooby slayer

iTrader: (4)

i will fit the wheel myself mate while im doing the rear housing, id just send it off and get it balanced for peace of mind, although id have to enquire as if they static balance it anyways it should be ok.

im gonna see if i can find any tests been done with them now ......

i use 1/2 unc stainless steel studs on the cat engines i build due to never corroding. i do have stainless 3/8 unc bolts here aswell tbh i didnt think about useing one, pointless though as all the others are stock tiny steel ones anyways.

scoooby slayer

iTrader: (4)

ive been doing a quick bit of math.

the gt4094r is rated at 800 hp max so im assumeing it would take the biggest housing 1.19 ar to achieve that power so as to allow the engine to flow enough exhasust gas.
now the 1.19 ar housing flows 37 lb/min of air meaning for every 1 lb/min of flow it can produce a maximum of 21.6 hp.
my current housing is a 0.85 a/r rated at 31.5 lb/min so should see 680 hp but i actually made 654 hp so 26 hp down.

now useing the same math im now fitting a 1.06 ar housing at 35 lb/min so max it should flow is 756 hp, the if i loose the same 26 hp in theory i should see around 730 hp.

wether it will work out like that remains to be seen lol

turnover

Give it 2.3 bar of boost and it will make the numbers,as long as your engines built for it just max out the 3 bar lol

J1mbo

iTrader: (1)

Sorry pal I'm with you

Yes open, we tried a 1.05 twin but back pressure is slightly worse and response didn't change so stuck with open

scoooby slayer

iTrader: (4)

well its reported as having 268/272 cams and having made 875 hp in japan on a t88 34d.
its holding 1.5 bar no problems and must have massive backpressure at that im sure, i know of someone who tested a 3.0 on a 0.95 a/r housing and backpressure limited boost to 1.5 bar !
im hopeful to get it mapped at 2 bar boost and still have less pressure than its currently got, fingers crossed it holds together, the current setup has done 4k miles with some track days in it so hopefully any issues would of shown themselves by now.


1.05 back pressure slightly worse ! imagine how bad my 0.85 is lol
im hopeing i wont loose as much spool as im thinking i will as it may be just getting rid of a bottleneck lower in the rpms aswell hopefully.