Gt3040 Vs T04z

[Bugis]

Advise & comments from u all please for my stock RB26dett/RB25det box please.

I'm purchased the

1. Haltech E11v2

2. HD fuel Pump

3. Sard 700 x 6

4. Sard FPR

5. Blitz High Mount manifold

6. Power timing belt

So which turbo more suitable for 500 ~ 600 hp. ( GT3040 or HKST04Z )

[Adriano]

Garrett TO4Z or Gt30r would be even more streetable.

[R31Nismoid]

GT30 will slot in just, GT35 would be more ideal though.

The T04z is bigger than the GT35 again, miles above what you need

Although you better pray to the gods that motor lasts at those kinda levels as if your gonna circuit it, it wont last forever unfortunately

[Bugis]

so, for my set-up GT3540 is the best deal ?

For future I will install the Tomei poncam 260/270.

[r33_racer]

you are talking about engine hp right? Not at the wheels? A large rear gt3040 should do it.

[DVS JEZ]

im using a T04Z on 24psi, got 570AWHP, it is quite laggy, but i guess that on the curcuit your always up in the high revs,

[r33_racer]

you know DVS32R...lots of people say that about big turbos. Not to be negative or rude, but its not always like that when your racing. On some tracks its almost impossible to maintain high revs to keep on boost. And once you fall outta that powerband for a split second...by god it feels like almost half the field just passed you.

[R31Nismoid]

Agreed ^^

[Kaido]

GT35R would be more suitable for 500's, but I hope you're going to add a full engine rebuild to that list for those power levels. Try not to get so hung up on a particular hp number, but rather go with what feels best when driving in real world situations. Alot of times, less power can be faster if that makes any sense.

[DVS JEZ]

you know DVS32R...lots of people say that about big turbos. Not to be negative or rude, but its not always like that when your racing. On some tracks its almost impossible to maintain high revs to keep on boost. And once you fall outta that powerband for a split second...by god it feels like almost half the field just passed you.

i agree with that too, ive had no experience with curcuit yet, lag is heaps annoying, its good for dynos and winning comps etc,

reason for my comment is my neighbour races his mini(yes totally different) and is always in the high revs, probably due to gearing etc

[r33_racer]

yeh...if you could afford gearbox and diffs to change ratios around so you could have say six gears and the ratios were tailored to suit your setup and the tracks you mainly race on...that could help...so your in the right gear and in the power band pretty well all the time...like i said before...one corner were say 2nd is too high and wheelspin is an issue and 3rd just bogs down and drops you outta powerzone...what do you do? Personally I wish more money was available.

[discopotato03]

I agree , with the cost of close spaced gear sets and final drives these days most find it easier to make the engines power characteristics suit the available gearing .

The GT3582R is probably going to cover what you want to do but cam selection and headwork will make changes to its power delivery . The secret would be making lots of mid range torque and not having it start at 5500 revs . Most people developing engines to do this use cam profiles with a fair bit of lift but not the extended valve open period (extended duration) . Cams like this don't need to bet set up with a lot of overlap which turbo engines don't tend to like if they have a restrictive exhaust side because they get reversion . If you can uncork the exhaust side and run high octane fuels the static CR could probably stand to come up a bit from 8.5:1 . Depends on budget I suppose .

Cheers A .

[Bugis]

guys,

Thanks a lots for ur input. I will purchased the GT3540 soon

[DVS JEZ]

what sort of power band are you talking?

my full boost is by about 4-4500 to 8500

is that any suitable for track racing?

how responsive are the twin setups? when are they seeing full boost

[AWD2Go]

I agree , with the cost of close spaced gear sets and final drives these days most find it easier to make the engines power characteristics suit the available gearing .

The GT3582R is probably going to cover what you want to do but cam selection and headwork will make changes to its power delivery . The secret would be making lots of mid range torque and not having it start at 5500 revs . Most people developing engines to do this use cam profiles with a fair bit of lift but not the extended valve open period (extended duration) . Cams like this don't need to bet set up with a lot of overlap which turbo engines don't tend to like if they have a restrictive exhaust side because they get reversion . If you can uncork the exhaust side and run high octane fuels the static CR could probably stand to come up a bit from 8.5:1 . Depends on budget I suppose .

Cheers A .

Problem is as lift increases generally so does duration. Yes you can increase lift without increasing duration to a point but then ramp angles are effected so greatly it cause valve train issues and any self respecting cam grinder wouldn't do it (after the practical max lift has been reached).

Another option is to run the longer duration cam but advance the intake and retard the exhaust, this can be used to offset a bit of the increase in overlap.

Edited January 25, 2007 by AWD2Go

[discopotato03]

I'm talking about the sorts of cams commonly available in the aftermarket - 26 something by 10 odd mm lift . If he wants to keep the state of tune of the engine suitable for std gearbox/diff ratios long periods cams may make it peaky . Falling off the cams is no better than falling off the boost threshold . The burning question is what useful power range and starting where .

Cheers A .