Harey

Tangles is arguing that it will alter the response: Nowhere did I say that it would not be great to see some tweaks to see what is possible, its a great start.

On a different note are there any rules to apply between boost reponse in 1st, 2nd, 3rd and 4th? For example if this turbo makes full boost at 2500rpm in 4th, what is the response in 1st, 2nd and 3rd? Same for say a GT3076 which makes full boost by ~3500rpm. Because I am sure a lot of people hear "full boost at 2500rpm" and think wow 2500rpm in every gear thats fantastic!

Housing changes do have a dramatic effect from my experience. Stao mentioned it as well when we were talking. I believe it is quite reasonable to make a blanket statement that using the same turbo and a larger exhaust housing will reduce response.

Ok I have never seen that before but I am not saying it cant happen. It would want to be seriously choked. I used many small exhaust housings and yes ones that do choke quite badly that still increase response.

How would it keep its response and gain top end power. Surely a larger housing will loose some response for the gain in top end power...

Yes I think a 0.8 housing will reduce the bottom end significantly! Yes of course if would be great to have more constant top end without sacrificing much bottom end but thats not generally how turbos work

This thing slams you in your seat all the way to 7k in 2nd gear. 3,500-5,500 is still very strong in 3rd gear.

Remember peaking at 5,000 is in 4th gear, in lower gears it will peak higher. Trust me it uses the revving nature of the RB in 2nd gear I agree it will be interesting to see how they go with boost control.

But the exhaust housing is the reason for the awesome response. If you change the exhaust housing to a larger unit then you loose response. Remember dynos are done in 4th gear. Not everyone needs a turbo that will pull to redline in 4th gear, your talking lock me up speeds on the street. 2,500rpm full boost in 4th gear would roughly correspond to 4,500rpm in 1st gear which is a big difference. I know dynos are done in 4th gear due to the 1:1 gearbox ratio but it can be misleading for someone wanting a responsive street turbo. This thing pulled to redline HARD in second gear, third gear was good but did loose some torque. If you want something to pull hard to redline in 4th gear then it cant be as responsive as this. The 3071 and 3076 are the turbos if you want the most response possible for 270-300rwkw. But if 250-260rwkw is enough, then something like this gives you fantastic response. Stao also took me for a spin a few weeks earlier with a 3582 wheel and a 0.82 housing. Yup the dyno sheet will show the turbo making big power to redline in 4th gear but there was basically no boost in 1st gear.

I have never seen one make 280-290 rwkw on a stock rb25. Same as I dont think I have seen a 2530 make 250rwkw...

I have a set of the blitz ones although havent put them in yet.

All the info you could ever want on E85 is here: http://www.skylinesaustralia.com/forums/Gu...85-t239271.html

I too can attest for this turbo, Stao let me take it for a spin on saturday. Car is super responsive, 1st and 2nd gear are just insane and third pulls very nicely but looses the insanity slightly. But by then your doing over any legal speed limit anyway. So if its response your after I would definitely recommend this. Thanks again for the drive! Would I be right in saying this is a HKS GTRS replacement?

FIXED FIXED FIXED OMG I CANT BELIEVE ITS FIXED!!!!!!! It was the Lower Control Arm Bushes! Launches are silky smooth and if I give it too much its just nice smooth wheelspin yeeehaaaa!!! Thanks to all that have helped! I would like to modify Sydney Kids axle tramp possible causes: - Worn Subframe bushes - driveshaft angle if car is too low - incorrectly matched shocks and springs - Lower Control Arm Bushes I dont believe tyre type and tyre pressures are the cause, I believe they just change how and when the problem is experienced.

A whole 0.5psi I know its a bit worrying but the tune should account for a bit more boost. if you are really worried try on a dyno. I would try 17psi so it flattens out to 18psi. will still be the same boost up top.

I agree with Ash. I would be looking at the boost controller settings. Most hiflows I have seen go straight to say 18psi, hold 18psi and then drop off at the end. Yours is 16psi at 3500rpm, 17psi at 4500rpm. It just gets over 17psi for a short time so I would hardly say its running 18psi. Set it up to go straight to 18psi or even a bit higher and then leave it drop off to 16psi near redline. Especially in the lower revs it doesnt hurt to have a bit of extra boost to get going. I dont think its an exhaust restriction because it still makes good top end power.

What was wrong with the stock one? I understand if you want to hear the bov sound then sure, but if you dont want to hear it and you want it to recirculate, whats the point??

Tie Rod end HICAS something Adjustable Castor Bushes Adjustable Camber Bushes Sway Bar links - Ball Type Since then have fitted Pineapples in the all round position (supposed to be the firmest way) And inserted washes in the lower diff bushes. He is fitting lower and upper control arm bushes at the moment. tarmac mentioned rear traction arms, do these have another name? have i already replaced those?

Tein Super Streets if you want to stick to a coilover. 4kg springs are fine, just stiffen up the shock if you are really pushing it. I just changed from stiff coilovers to bilstein shocks, king springs and standard rubber top mounts. This is softer and lot more comfier but still handles very well. Most times on australian roads stiff coilovers are worse at handling cause your bumping all over the place.

Yeah I have put the pineapple settings to the side because if the best outcome is solid mounting the subframe then why would changing the diff pinion angle help. However I think the next step is to change the lower and upper control arm bushes. If the subframe mounts were the main issue, surely the pineapples (on all round which is the stiffest setting) would have made some difference. Chris also said on saturday he filled out the diff bushes with some washes and there was no difference. Chris said this will mean we have replaced or modified every rear end bush. If the control arm bushes do not change anything then I will get the subframe and diff bushes done.

Please reread this post, it has very good advice. I was just about to type a very similar thing.

Recent post in RB25 dyno results thread: "unopened Neo Rb25det -3076 56t with .64 housing -highmount AM Performance stainless steampipe manifold with HKS 38mm gate -Profec Spec B -600cc injectiors -fmic -3.5 inch exh -Nistune 310 rwkw @17 psi at around 6800 rpm fullboost by 3500 roughly 480 nm torque at engine (calculated) " POW! I would love to see a dyno sheet too.

Thanks for that. I am still a bit confused by terminology. I am going to have a look at my receipts and see what has been done so far and what is left on your list.

Agreed that would be the ultimate for what you want. If you cant afford HKS get a Garrett GT3071.

Hmmm I spent quite a while talking to Luke (I think) from Fulcrum suspension for my R34 GTT and he was telling me the aus spec Tein Super Streets are softer springs as well as dampening to match them. He mentioned 4kg front and 4kg rear for the aus spec compared to 6+ for the jap spec from memory.