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Realistically neither of us can say what will happen, were both just guessing. Assumptions based on an understanding of how the system works. You seem to think theres little that can go wrong as the high load areas are R&R enough to soak up most of whats going on. I think that the change in exhaust restriction (bigger turbine and housing) coupled with the change in compressor efficiency (flow from the wheel aero iteself and difference in housing AR) can result in the ECU reading areas of the map which are irrelevant to what its actually doing. Running at an AFR and ignition combo with will start to see signs of det relatively easily. I think it is far more complex than high load or low load, otherwise we would not waste money on expensive tunes. In my own case Ive had my car tuned OKish rich but with very little timing and it would ping its guts out the moment something wasnt 110%. Have also changed an exhast cam for a slightly larger item (both oem) and completely lost the tune. That tells me the sweet spot for a tune isnt 'thereabouts' in all cases and these things can be pretty sensitive. something I would prefer to advise people against. Not to say Ive never put a T28 on a CA18 and thrashed its guts out as is for years.... But its just not the advice I would like to give, given my other experiences and understanding of how the thing works.

Realistically, as long as you are within the bounds of the original maximum load on the map, there is no cell on the original maps that does not have a commanded air-fuel ratio and timing that is approximately correct, or at worst, really rich and retarded. The load is measured by AFM, so it's not as though the shenanigans caused by MAP sensing + engine/turbo mods comes into play. Nissan pretty much mapped all the load/rev combinations, and those that were inaccessible under normal operation (really high load at really low revs for example) just had nominal values in them. But you're not going to be able to get to those regions of the map with a bigger turbo anyway.

The one place where you can get into trouble is if you run off the end of the original map's load axis. In this case the ECU has no option but to keep using the commanded mixtures and timing used in the last column. On an RB25DET, these are rich and retarded, so should be safe. But if you push it past what the injectors can do, then of course you could lean it out. But that has less to do with the management than it does with fuel system constraints.

I think where we differ is our faith in the AFM reading.

You seem pretty confident in it but for me I see it as a harmonic sensor, not to be relied upon when changing the setup. I don't think the voltage from one setup to the next on the same AFM would be identical in reading per unit of flow.

Just FYI; we are allowed to 'agree to disagree' lol

Some further updates, for the billet SS1 and SS1.5 .

The current SS1 runs a 71mm cast comp wheel, the newer version will be running a 60mm billet wheel with blade edge extension, smaller hub longer and cropped blade profile. This 60mm wheel should have the equivalent output as the current 71mm cast wheel with lot less in weight. Targetting is around the 240rwkws mark on 98 with excellent response. This wheel is ideal for people with Rb20det and SR20det engines.

60mm.jpg

60mm2.jpg

This is the SS1.5, the current 71mm compressor on the SS2 is rated to about 500HP, this 64mm wheel in theory should provide around the 470HP mark. I've packed large blades with extended tip on this wheel using a small 12mm center hub. Final goal would be 20psi by 3000RPMs using the SS1PU turbine while making towards the 270rwkws margin with very sharp throttle response.

64mm.JPG

64mm2.jpg

I'll be intrested in a ss1 billet if will make 20psi before 3500rpm on a sr20det and still make 260rwkw on e85 how much will these be with a s14/15 housing

Just wondering 337 pages and i still think theres not one trap speed for a hypergear..anyone going to drag race with one?

cheers

darren

Had new semi's fitted with the intention of hitting the strip, but my drivers seat broke so I didn't get down there before I left for Europe. Will be getting some new seats when I get home in January and then I'll go get a trap speed :thumbsup:

Stao is that SS1.5 billet wheel different to my SS1PU wheel?

Hey let us know how your ss1pu billet goes on your sr20det if it is 500rpm less laggier than my current turbo td05 and make similar power I'll get one

Just wondering 337 pages and i still think theres not one trap speed for a hypergear..anyone going to drag race with one?

cheers

darren

Waiting on results from SAU Nats

As soon as they are posted I can give you some airport drag results but it was fairly bumpy and rocky surface.

How much do the drags in Sydney cost because I could make it to them once my water meth is installed and tuned

This is little bit of a lolz result. That is a ATR43G2.5 used on a fully stock Sr20det with factory cams as a bolton turbocharger internally gated. 290rwkws on 18psi E85. Good power, bit laggy :P

sr20detG4290rwkw.jpg

Hey let us know how your ss1pu billet goes on your sr20det if it is 500rpm less laggier than my current turbo td05 and make similar power I'll get one

Will do man. Will be tuned in Jan.

PM me if you just want to add me on FB, I update photos on my build every week or so.

Further updates on the Billet T67:

I've made one more version using the FNT turbine setup. And I guess the best part is this housing can be made to be complete OEM bolton to stock manifold and dump using all lines. So here it is a OEM bolton T67 how ever don't expect of getting external gated proper manifold result using this as a stockie replacement. The FNT version is expected of hitting much better mid range power band, I will trail both versions on my current high mount external gated setup.:

ss3.JPG

ss3rear.JPG

Standard Billet T67 and FNT turbine ended T67

t67ss3.JPG

Just wondering how that big compressor will go fouling the manifold..does it need a big spacer ??

Could you make one with a 3 inch Vband rear instead of that silly nissan design or would it need a seperate WG hole?

.

Just wondering 337 pages and i still think theres not one trap speed for a hypergear..anyone going to drag race with one?

cheers

darren

Lol...this pops up every 6 months or so doesn't it :laugh:

Well assume you have a proper exhaust system that makes no differences.

The FNT housing can also run on 3.5 inch Vband, its just matter of what ever bolts onto the back of it.

Well assume you have a proper exhaust system that makes no differences.

The FNT housing can also run on 3.5 inch Vband, its just matter of what ever bolts onto the back of it.

cool :thumbsup:

How much of a difference is it to use the vband rear rather then the Nissan style?

Better flow or performance?

yeah not a performance thing Its just ease of fitment..

Just wondering how that big compressor will go fouling the manifold..does it need a big spacer ??

Could you make one with a 3 inch Vband rear instead of that silly nissan design or would it need a seperate WG hole?

.

Lol...this pops up every 6 months or so doesn't it :laugh:

Yep and then people will tell you they are about to go..then i will ask 6 months later again..lol

So G3 internal vs T67 internal dyno graphs will be interesting..

The if you run them on a stock manifold as a bolton none of them is likely to go pass 280rwkws @18psi. Its just an option so you can use it till when a proper setup or a proper bolton manifold come by. How ever the FNT ext gate version should have lot more meat in the curve compare to standard.

Also question for some Gurus. Will you loose VCT by installing aftermarket cams?

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