Rb30 Build

[Harey]

He would be talking about RPM, and my guess would be about 6k rpm?

See I think thats misleading as the rpm behaviour is 1-2,000rpm difference between 1st gear and 4th gear. So if the dyno shows the power dropping off above 6,000rpm in 4th gear, it might drop off at 6,500 in 3rd and not drop off at all in 1st and 2nd gears as its above the rev limiter.

So if your mostly in 3rd and 4th gears you will notice the power dropping off whereas if you drive on the street and mostly in 1st and 2nd under power then you wont notice it at all.

[r33_racer]

We don't have a speedo in our car so I can't comment, but purely racing exp here, around 6500rpm it would die off, but for most tracks it was pretty good.

[r33_racer]

Yeh but you don't build high powered cars to race on the street...

[zebra]

See I think thats misleading as the rpm behaviour is 1-2,000rpm difference between 1st gear and 4th gear. So if the dyno shows the power dropping off above 6,000rpm in 4th gear, it might drop off at 6,500 in 3rd and not drop off at all in 1st and 2nd gears as its above the rev limiter.

So if your mostly in 3rd and 4th gears you will notice the power dropping off whereas if you drive on the street and mostly in 1st and 2nd under power then you wont notice it at all.

WOT is WOT, the power will still drop off no matter what gear it is in.

Youre right in saying you might not notice it as much in 1st gear, but it still happens.

[Harey]

Yeh but you don't build high powered cars to race on the street...

The thread starter said:

"Hey guys heres my build plan would this be adequate just for using as a street car"

If someone wants a high powered car to use on the street I think thats their choice. And if they decide to, surely you want to use the power at legal street speeds.

[Harey]

WOT is WOT, the power will still drop off no matter what gear it is in.

Youre right in saying you might not notice it as much in 1st gear, but it still happens.

How can you say that WOT is WOT. 1st example, full boost will be later in 1st gear then it is in 4th gear etc. The whole turbo powerband shifts to the left as you get higher up in the gears (and hence speed). Yes its not huge but can be 1-2,000rpm between 1st and 4th which is considerable.

So for a street car that will do most accelerating sub 100km/h I would choose the GT30 0.82. Track car and drag are different scenarios.

[r33_racer]

Lol even though it is a street car, he will no doubt give it squirts here and there, probably race people as well because lets face it, you get amped up on occassion and it happens.

But you are right, the gt30 would be the best pick. It is a good responsive setup that nets good low-midrange power.

[Harey]

Lol even though it is a street car, he will no doubt give it squirts here and there, probably race people as well because lets face it, you get amped up on occassion and it happens.

But you are right, the gt30 would be the best pick. It is a good responsive setup that nets good low-midrange power.

Haha no doubt he will still give it squirts and race people. But most street races and street squirts involve a low to moderate starting speed and most only last 1-2 gears. Meaning that the more responsive car will jump out in front and make it hard for the less responsive but higher peak power car to come back before you run out of road or find traffic. Another consideration is traction, the GT30 will be responsive and also progressive in the way the power/torque hits so you will have maximum chance of maintain traction compared to the GT35 which will be more likely be wait wait wheelspin especially at lower street speeds.

But if you are a nutcase and want to do really silly stuff on the street etc etc then go GT35 lol

The other consideration is getting your setup really sorted out. You will find most cars with lots of modifications will take a number of fixes and improvements to get the most out of the turbo. A larger turbo will require more and more things to be sorted to actually reap the rewards of the larger turbo. There are countless setups that end up only running the power of a GT30 with a GT35 due to being out of budget or frustration at not being able to find the answer. This is poor as you have less response for similar top end. Whereas it will be a lot easier to get close to max out a GT30 which will provide excellent response.