Jump to content
SAU Community

Recommended Posts

Anyone else gotten over the apparent " 250rwkw " limit using standard compression and pump fuel? My car is geting dyno tuned next week and i will be really dissapointed if the limiting factor is compression.

We have had 305 rwkw out of an R34GTT. Tomei 260 Poncams, R33GTR intercooler, ported and polished cylinder head, standard head gasket (I don't use thick ones) and a Garret GT30. It wasn't all nice to drive, too peaky, lots of lag, poor throtle response.

I'm quite suprised the GT30 didnt fair to well in terms of response? Usually you can get max boost at a tad over 4000rpm on an SR so surely it would have been better on a NEO?

Well it depends on the setup eg manifold design and what the target boost pressure is. However here's a nice example of a HKS GT3037 (aka GT30R with a custom T25 flanged housing) with a 0.87 housing on an S14;

post-19001-1157454882.jpg

So I naturally would have thought the response would have been better on the RB25?

You can read more about that chart I posted up here;

http://www.nissansilvia.com/forums/index.p...howtopic=185086

(One thing to note is I am not sure if the 0.87 in the HKS T25 flanged is the same as the 0.87 in the GT T3 housings, even with the same turbine...) Sorry for going OT but yeah, interested in how the GT30R works with the NEO.

Edited by Busky2k

Interesting topic id say it would be the same for the neo as it is the non neo and obviously depend on the set up.

My question is this, Would a large turbo making 250rwkw easily put less stress on a engine than a small turbo at high boost / peak to above peak efficency?

  • 3 weeks later...

Just deciding on a turbo for a customers car, 34gtt, either a 2871inwg in a modified nissan ex housing, or a 3037in wastegate, or a gt35r .84 ex wastegate , he wants 300rwkw, but i think this will be pushing it. Any ideas?(99% street 1%drags)

Just deciding on a turbo for a customers car, 34gtt, either a 2871inwg in a modified nissan ex housing, or a 3037in wastegate, or a gt35r .84 ex wastegate , he wants 300rwkw, but i think this will be pushing it. Any ideas?(99% street 1%drags)

1. does the customer have stock internals...?

2.if doesnt want to crack it open hks 2835pro s or 3037 pro s the 2871 you get too much back pressure due to small ex housing.

3. if engine is going to be cracked open i would suggest the gt35r and that will take u way over 300rwkw.

4. if u want a respnsive fun car then i would more inclined to go for the 2835 or 3037 . 2835 pro s is 420ps and the 3037 pro s is 480ps .

cheers

  • 1 month later...
1. does the customer have stock internals...?

2.if doesnt want to crack it open hks 2835pro s or 3037 pro s the 2871 you get too much back pressure due to small ex housing.

3. if engine is going to be cracked open i would suggest the gt35r and that will take u way over 300rwkw.

4. if u want a respnsive fun car then i would more inclined to go for the 2835 or 3037 . 2835 pro s is 420ps and the 3037 pro s is 480ps .

cheers

sorry to bring up this old thread but whats the limits on a NEO RB25DET before you gotta crack it open??? im askin coz i have heard anywhere from 250awkw to 350 awkw which is a big difference... and what would be the best turbo to use (street car looking for good response) up untill internal have to be replaced? would it be smart to just high flow the stock one?

I think 350rwkw is massively over generous.

it would late 5 minutes. maybe.

GCG high flow rocks.

If you are in Melbourne....

350 is over generous hey??? that's what i thought... i just picked up an old fast fours mag of a mate yesterday with the tunning guide for RB20s and RB25s and it says in there that if you wanna run anywhere around 300rwkw on stock internals then you better be very careful... so i guess aroung 270 - 280 would be ok if the tunning is right... once i get to about 200rwkw i mite ivestigate cgc bit more... thanks for you reply..

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
    • You don't have an R34 service manual for the body do you? Have found plenty for the engine and drivetrain but nothing else
    • If they can dyno them, get them dyno'd, make sure they're not leaking, and if they look okay on the dyno and are performing relatively well, put them in the car.   If they're leaking oil etc, and you feel so inclined, open them up yourself and see what you can do to fix it. The main thing you're trying to do is replace the parts that perish, like seals. You're not attempting to change the valving. You might even be able to find somewhere that has the Tein parts/rebuild kit if you dig hard.
    • Can you also make sure the invoices on the box (And none exist in the boxes) are below our import duty limits... I jest, there's nothing I need to actually purchase and order in. (Unless you can find me a rear diff carrier, brand new, for stupidly cheap, that is for a Toyota Landcruiser, HZJ105R GXL, 2000 year model...)  
×
×
  • Create New...