whatsisname

Go & compare the price difference btw Nitto's & RE540S's! HUGE difference & not in the Nitto's favour. RE540S's cost me $1180 balanced & fitted (235/45/17 - 255/40/17) Yokohama A032R's & Dunlop D01J's were both considerably more expensive, but compared to Nitto's they were dirt-cheap!!! Having physically compared the Nitto NT555 & RE540S I can say they are pretty much the same in tread softness, it's the soft sidewall that gives the Nitto its drag abilities. Trust me when I say the RE540S is VERY grippy in a straight line for a cornering tyre. If you want to run decent 1/4 times on a street legal tyre & don't want to spent big $$$ give any of the A032R, D01J, RE540S rubber a go. Doing big burnouts on the RE540S isn't needed, & as the HSV owner @ the 'plex proved it'll ruin any advantage the soft treaded RE540S gives. The problem I see in running with full slicks is it's no longer a *street* set-up (i.e. HPI challenge) IMHO Here's a thread I started a while back - http://www.skylinesaustralia.com/forums/sh...ighlight=RE540S

Yeah Clint AIR SM is scheduled for 01 Feb. If it's night meet or a cool day I'll be running, otherwise I'll wait till later. Mind you as it'll be the first meet in ages it's going to be packed! :eek: We'll see how the voting goes but I'm guessing the 31st will be the go!

Joel, The LJ only ran that quick as it was geared (diff & box) for 0-400m only! It was/is flat out doing much over 185km/h. Your car would manage a 12.8 if you set the gearing up to suit 0-400m, in fact seeing as you like 0-160km/h & off the lights stuff why don't you? Yeah I knew Jaffa was having H/C done a while back. Jaffa's LS1 suffered from the dreaded oil consumption So why not go for it in the rebuild. The 280+rwkw Commodore I dreamt about has H/C too (+ a 300kw eng to start with) I also dreamt about another successful 80km/h run vs. a 240+rwkw Commie Ute. 260rwkw 1500kg (car with driver) 300rwkw 1700kg (ditto) I would've thought the above would be closely matched. I could be way off though? I remember reading somewhere a kg removed is worth more than a hp gained.

If an exhaust system is restrictive enough a 1 second improvement is very possible. Ask any of the SA guys @ a recent Tilbrook dyno day. SPOOLIN's modified GTS25t made 219rwkw & then after replacement of the *very* restrictive cat & cat back section followed up with 282rwkw. A gain of 63rwkw is more than enough to reduce a 1/4 time by a full second. Bottom line is...... until someone goes out & runs 13.3 or less (what I consider low 13's) in a factory standard GTS25t using only slicks, high octane fuel & advanced timing then I'm not convinced. Maybe my last comment will gee someone up to prove me wrong If so good on 'em.

Joel, I'd rather have something that's quick 0-100km/h..... 100-200km/h.....& 200km/h-0 No good being quick to 100 but nothing left after that. I had an interesting dream the other night...... I was side by side with a 280+rwkw Commodore doing 80-90, we both accelerated & I didn't see tail lights x2. With very grippy tyres (i.e. RE540's - D01J's) 250+rwkw can be used to full effect on the street (once heated) although very grippy tyres can be a tad costly for daily use. Back to the topic...... A STOCK GTS25t using ELF Turbomax (+ advanced timing) & running slicks would NOT get into the low 13's. Of course it depends on your definition of stock? I take stock as meaning factory standard, no modified parts AT ALL apart from the slicks. You can advance the timing as your not replacing anything but that's about it. High 13’s but not low!

When would you like to cruise?

Went on a cruise with a few of the LS1 guys the other night (last minute thing so I didn't get to post it up) Awesome fun First cruise I'd had in months! My new power & grip saw me notch up a few wins. Yeah we should have a cruise prior to the 4,6 Rotary Nat's. Either Fri 24th or 31st?

Joel, Vince Rigoli selected the combo & Precision Turbochargers (Sydney based) built it. I've been really happy with it so far Clint, Sounds good mate.

Well nothing really! 13-14psi it about as safe as I can get 16psi is the limit on my stock injectors @ the current f/pressure (hit "max duty" @ 16psi 7000+rpm). I could go & up the f/pressure "again" & then wind the boost to 15-16+psi. I'd say my turbo is good for a genuine 450-500hp(fly) @ the absolute maximum. But to be totally honest I'd rather play it a tad safe & wait until I get bigger injectors.

Your turbo has ~800-1000rpm more lag than my combo. About what I'd expect given my extra 500cc & T3/T4. For serious traction (hills/drags etc...) I'd go get those RE540S mate. For daily use the FM901's are the go. 100rwkw gain, ahhh you'd hardly notice that the road :burnout:

Awesome results mate! 235rwkw in a 32 is serious grunt :uh-huh: Martin comes up with the goods yet again Most stock Japanese injectors can handle quite a bit of extra f/pressure, if/when it's needed. I've heard figures of 90+psi without a drama!

If it falls off in your hand it might be time to give it a rest :Oops:

Clint, When I dropped in the other day Martin mentioned 216rwkw with more to come once you get the injectors sorted. Very impressive so far mate! John started up & moved the 33 drag beast into the workshop while I was there too. It sounded bloody awesome :uh-huh: Had a look @ his new Volk TE37's + Nitto's, damn they're sticky tyres!

What do you expect when your first 2 posts on this forum contain...... "What a crock of crap. Every rb25 ive seen do more than 300 at the wheels has cracked a ring land or something like that. There just not suited to high boost . There like a NA motor with a turbo on them. Rb25 :lol: :lol:" Telling a long time forum member his POV is a "crock of crap" is a great way to introduce yourself to the forum. Add to this the fact you own an R32 GTS-t (no chance of RB20 bias there ) You keep mentioning the ability to run higher boost with a standard internals RB20DET, there's no need to run higher boost to make the power when you don't need to!? I rather 250rwkw on 13-14psi than stress a "internally standard" 80-100+K engine on 18-20+psi. I'd like you to direct me to the known facts on weaker RB25DET rods? Not that I'm doubting your claim but I'd like the "known facts".

Cam, 257rwkw is just on 345rwhp, exactly the same rwkw/hp as mine (I only run 13psi though).

I take it you haven't seen many 300+rwhp RB25DET's then! I've seen/witnessed/heard of many internally stock RB25DET's that produce a reliable 300+rwhp, mine included. There are a few internally stock RB25DET's in the 400rwhp region that haven't cracked rings or pistons & are still going strong. The red JMS GTS25t is one I've watched run 290-300rwkw quite a few times, & it certainly would cop a hiding! A 200rwhp RB25DET will crack a ring land if it's poorly tuned, or any of the support systems fail (f/pump etc..) Both the RB20 & RB25 DET engines have great potential, but you can't overlook the extra 500cc capacity for driveability. It'll bring a bigger turbo on boost sooner, better off-boost response & so on. That's not to say the RB20DET doesn't have advantages over its newer/larger brother. Lower compression being the main one. While talking CR's it's interesting to note the CR chosen by many of the Japanese tuners (& now a few Aussies) CR's in the region of 9.0:1 & over are not uncommon @ all! It all comes down to the tuning & fuel used. John (Munro) on these forums has an RB26DETT (OS Giken RB30 kitted) with 9.1:1 CR This CR & extra capacity has his 2835R's spooled & providing solid boost by 4k.

G'day J, I'm guessing it's time to welcome you to the RB25DET ECU timing retard! Once the airflow goes above the AFM voltage range it pulls lots of timing to keep everything nice & safe. It just so happens that the nice denser air your FMIC is allowing has caused the above to happen. I'm also guessing that once your AFM voltage drops drop back into its normal operating range (retard timing - less power & less airflow) that the car comes on strong again. This is because ECU has advanced timing once again (probably ~6000rpm). The more air through the AFM the worse this will get. I had 3 big ECU commanded timing retard dips in my power curve @ the 225rwkw mark. These can be felt as huge flat spots, & seen as brief 15-30rwkw drops on a dyno run. Having said (written) all this sometimes there's freak ECU's that don't seem to retard timing!? Bugalug's car is one of these! Like your's J, Bug's is a 95 model too. Options to get around this issue are just the same as MYGTST listed to avoid the fuel cut: Programmable ECU Z32 AFM & remap - not easily done on the 33 Fuel cut defender - "can be" dodgy/dangerous Turn down boost - yeah right! Do nothing - & drive a car that feels like someone keeps pulling the handbrake on & off! Why doesn't the timing retard & boost/fuel cut occur @ the same time? Buggered if I know? Anyone???

I didn't end up getting a chance to drop by So how'd she go Clint? The heat in the dyno bay wouldn't have helped. 40+c for sure!

Steve, No mate. The ECU is still aware of exactly how much air is entering the engine regardless of temp & density. The AFM will register the cool denser air (via the increased voltage signal) & ensure the fuel requirements are met to maintain the programmed A/FR.

Another thing to keep in mind with the RB25DET ECU fuel cut....... As the ECU uses the AFM voltage signal (anything over 4.5V) the point it cuts will vary depending on air temp & density. A modified RB25DET still using the stock ECU may well hit the FC @ 8-10psi on a cool night, yet it'll run 10-12psi on a mild/warm day without a hitch.

Yeah nothin' wrong with the stock ECU once mapped to suit mate. If you keep tweaking & need further tuning then I guess it starts to get a touch costly. It should make good power. You never know it may well get more than mine. Considering the 32 is lighter you won't need as much grunt to be as quick anyway!

Clint, What ECU are you using? I'm guessing you're getting Martin to do a remap of the stockie? Wouldn't mind popping down for a look if thats the case. I'm just down the road from Tilbrook's Matt

For anyone who didn't already know & is interested, go check here - http://www.fordxr6turbo.com/forum/index.php?act=SF&f=3

THAT IS BLOODY AWESOME!

GTS-t VSPEC, The LT12 is one of Microtech's new laptop programmable ECU's that can be configured for the GTS25t. It comes loaded with base maps to suit (like the PFC) & then plugs straight into the factory loom. There's one extra sensor that can be installed for total functionality (intake temp) but it's very simple & taps into the existing AFM wiring. I'm really happy with my LT12 The engine is responsive regardless of throttle position or rev range, it idles nicely, makes good power & hasn't cost me all that much to get it installed & tuned. Fuel economy I don't take much notice of but it's @ least on par with the stock ECU.