My E85 Experience

[Dale FZ1]

I reckon exhaust restriction or stuffed cam timing personally.

I didn't see any mention of making changes other than to E85 and the quieter muffler. Still, not hard to check cam timing without wasting time and money before returning to the dyno. Then I'd go and drop the quiet muffler and see just how much it picked up.

Injector duty cycle beyond calculated/expected values for the power output to me says setup issues with the fuel system ie. pump. Is the wiring allowing the pump to work to its rated capacity? Check with the multimeter to remove doubt.

The GT30 0.63 A/R housing should prove restrictive in terms of max airflow capacity (compared to the 0.82), but the E85 should allow bags of extra ignition timing as per Mafia's expoits running WI. That's how he made power from that turbine setup.

Sure this thing's been fuelled up (but I wonder about that lambda value not being rich enough, given it's essentially an alcohol fuel), but has the ignition timing been cranked up to take advantage of the knock resistance E85 offers?

Edited September 2, 2010 by Dale FZ1

[scotty nm35]

You should make good gains without touching the timing... Just because it has higher knock resistance doesn't mean you should lean on it too hard or the piston skirts will take the brunt. (my 2c)

[Dale FZ1]

Alcohol fuel has lower calorific value per gram of fuel. Changing the fuel type and adding the right quantity won't make significantly extra power just by that change alone.

The extra stick will come from making appropriate ignition timing changes that capitalise on the knock resistance of the fuel. Same process as tuning for racing fuel or avgas really. It would be interesting to see what the ignition map for this particular car looks like, just to quell any back/forth about this aspect of his tune.

Edited September 2, 2010 by Dale FZ1

[R31Nismoid]

I didn't see any mention of making changes other than to E85 and the quieter muffler. Still, not hard to check cam timing without wasting time and money before returning to the dyno. Then I'd go and drop the quiet muffler and see just how much it picked up.

You can see from the graph the boost was increased 4 or so PSI - so there were changes if not mechanical.

But i mean the setup wasnt correct BEFORE the E85 trip. His PULP results are... below par IMO.

[DVS JEZ]

drop the exhaust before the cat and see if its melted at all.

we had a s13 sr20 loose 40kw.he put on a supposedly high flowing cat which we found out was a cheapie, and was really restricting flow, putting in a decat and testing made the power gain the 40kw back.

just food for thought.

[Dale FZ1]

the setup wasnt correct BEFORE the E85 trip. His PULP results are... below par IMO.

Agreed.

As I suggested, there is at least a couple of things requiring a check over to diagnose what's going on.

I wonder what his tuner suggests?

[R31Nismoid]

I'm surprised the tuner didnt look into it all before the E85 tune to be honest.

[Bond]

Yes boost was increased by 4psi. I'm not sure if we were able to wind the boost up on 98. I think i will check the cat and then the muffler and go from there.

[Harey]

The GT30 0.63 A/R housing should prove restrictive in terms of max airflow capacity (compared to the 0.82), but the E85 should allow bags of extra ignition timing as per Mafia's expoits running WI. That's how he made power from that turbine setup.

But the standard factory housing when hi flowed can make 250rwkw and that is definitely smaller then a GT30 0.63 housing.

There is a significant difference between a GT3071 and a GT3040 (GT3082). A 0.63 housing is fairly restrictive to top end power on a GT3071, but on a GT3082 it would be more equivalent to a 0.82 housing on GT3071.

Something is definitely wrong.

[Dale FZ1]

There is a significant difference between a GT3071 and a GT3040 (GT3082). A 0.63 housing is fairly restrictive to top end power on a GT3071, but on a GT3082 it would be more equivalent to a 0.82 housing on GT3071.

Something is definitely wrong.

Put a GT3071 and GT3082 both with the same turbine housing side by side on a bench. Doesn't matter if it's 0.63, 0.82 or 1.06. Turbine specs will be identical. Airflow capability through the turbine will be identical. Getting a visual makes it easy to understand that using the same rotor, housing, and wastegate configuration/size will result in the same total flow capacity.

My earlier comments about the Mafia related to how he got the best from that turbine spec, achieved very stout results but needed WI as insurance against knock. Provided Bond can check/rectify issues with any exhaust restriction or whatever other problems exist, he should be able to make strong torque through the range by tuning that capitalises on the characteristics of E85.

In my view that is done by using lots more igition timing than is used for tuning with only pump petrol (no WI)

But I agree there is something wrong.

Edited September 3, 2010 by Dale FZ1

[scotty nm35]

Pumping a heap of timing into an engine that obviously has a restriction is a disaster waiting to happen, regardless of fuel.

Without seeing the car I wont comment but the turbo specs should be good for well over 300kw on 98 right?

[blk15]

I apologies as I have only done a quick search which was fruitless, does anyone know of or have an official list of E85 stations?

I am considering going E85 however am unsure of the availability.

[Trozzle]

Caltex have theirs on their website afaik, but it might just be the intended stations for their phase1 rollout

[Dale FZ1]

Pumping a heap of timing into an engine that obviously has a restriction is a disaster waiting to happen, regardless of fuel.

Agreed. And that has been the thrust of comments - get the setup right, and THEN tune to suit what he is running.

the turbo specs should be good for well over 300kw on 98 right?

Not likely. The GT30 0.63 IW combination is restrictive at higher mass-flow rates. If you had the opportunity to sit one beside a 0.82 or 1.06 A/R housing from the same family it's easy to see why. To have a realistic chance of hitting 300kW with a reliable tune would likely require either E85 or WI.

[JonnoHR31]

But the standard factory housing when hi flowed can make 250rwkw and that is definitely smaller then a GT30 0.63 housing.

There is a significant difference between a GT3071 and a GT3040 (GT3082). A 0.63 housing is fairly restrictive to top end power on a GT3071, but on a GT3082 it would be more equivalent to a 0.82 housing on GT3071.

Something is definitely wrong.

just to clear up your confusion the first 2 numbers refer to the turbine side, in this case both turbos mentioned use a gt30 turbine, which is usually 60mm in diameter. therefore the turbine housings between these turbos are exactly the same and 100% interchangeable. a .63 gt3071 housing is identical to a .63 gt3082 housing.

the second 2 numbers refer to the compressor wheel. it used to be used in the same way as the turbine side, as in a gt3040 (now gt3082) was a gt30 turbine with a gt40 compressor, similarly a gt3037 (3076) used a gt37 compressor. but this was changed and now the diameter of the compressor wheel is used instead, so a gt3071 has 71mm compressor wheel, a gt3082 has a 82mm compressor wheel.

[discopotato03]

Yes all three use the same 60mm 84 trim GT30 turbine wheel so the housings should interchange .

One thing no ones mentioned is the fact that of the three only the GT3076R/GT3037S has a port shrouded compressor housing and that definitely has some functional value other than the truck whistle .

Sorry to bring HKS up again but you have to remember that they went to the effort of making their marketed versions of Garrett turbos work in engine/car specific forms .

Now , most of the HKS spec single turbos for Nissan RB sixes use a port shrouded compressor housing ie 2530Kai/GTRS/2835 Pro/3037 Pro/3037S .

Amongst the turbos Garrett make and market themselves only the GT3076R has it and I reckon its because it was a HKS spec Garrett turbo to begin with . That port shrouded comp housing makes the GT3076R/3037S turbo a very wide ranging unit because of it and allows you to use smaller A/R turbine housings and not get compressor surge . Actually thinking about it HKS had the smallest proper GT30 turbine housing size ever made and it was 0.61 A/R .

I really don't think it would be a huge issue to run a 0.63 A/R Garrett turbine housing on either a GT3071R or a GT3076R , the problem with doing it on the GT3071R is the lack of a port shrouded compressor housing and this would show up any wheel speed miss match between the compressor and turbine wheels . If you look at what a "GT2835R" is you'd think that its cropped GT30 turbine if anything would attempt to spin the compressor wheel faster than the full sized GT30 turbine could for a given turbine housing size (yeah I know 0.63 vs 0.68) . HKS uses a port shrouded comp housing on that turbo and they wouldn't if they didn't have to .

GT3040R/GT3082R has always been a bit out there and Garrett really should have reverted it to the HKS spec version (50T rather than 56T) compressor after HKSs six odd year exclusive sale time ran out .

Some of you may have noticed that the GT3582R is now available with a factory Garrett port shrouded compressor housing and it would be a must have IMO if you wanted to run the 0.63A/R turbine housing , and if it were me the 0.82 one as well . If it fits a GT3582R it will fit a GT3082R and while possibly not cheap it should be a step in the right direction .

Now to turbine housing A/R . If you use small ones its the hot side that will eventually run out of flow and do it earlier than larger sized turbine housings . Thats the price you pay for wanting to get the turbine up to speed earlier in the engines speed range . You have to match the turbine/housings gas flow to the compressor and its housings flow potential and its the ported compressor housing that gives more flexibility in this area . Small turbine housings and big compressors can be made to work provided the compressor housing can cycle the extra air that big compressor wants to pump when the turbos rotating group speed comes up early in the engines rev range . Obviously its better if the comp wheels capacity matches the hot sides capacity but its not always the case .

Personal opinion only but I reckon the smaller trim GT37 compressors are a better idea if you want to use the 0.63 A/R GT30 turbine housing and as we know the 52 comp trim version is available because I tracked them down and GCG now stock them - yes in port shrouded comp housing form . The 48 comp trim version is a rare bird now and I think out of production .

I actually wonder sometimes if I should have optioned for a 0.63 A/R turbine housing for my 52T GT3076R , its still new in its box and I may put that idea to GCG if they have one nor nil or SFA changeover . E85 is plainly now going to be a reality and I'm not so concerned about top end Kws in a RWD road car , having a sweet responsive low to mid range is much more important in the day of the radars etc than a power number .

I really do think a 63A/R 52T 76R would be to an RB25 what twin GTSSs would be to a street GTR , good responsive street power thats more than enough 90% of the time . Wheelspin city without trying to hard and fast enough to put you behind bars quicksmart .

A .

[Bond]

Pulled the cat off today and there is no restriction in there

Besides the muffler (will drop that on the dyno) what else could be causing such a low output?

[wolverine]

Timing belt might be out a tooth.

When was it last changed?

(I have a GT3040 (0.82 turbine housing) making 278rwkw at 17psi on 98ron)

[Bond]

Timing belt was changed before i bought the car. How will i tell if it has jumped a tooth?

How do you find the 0.82 housing?

[wolverine]

The 0.82 is fine and delivers fairly linear power. The turbine housing you are using is not your issue so I wouldn't worry about changing it. There is more power to be had when you sort out the issue/s.

Definitely drop the cat on the dyno and rule out the most obvious stuff first get your mechanic to check that the timing marks line up.