Boost Response Help!

[Revenge]

Hey Guys,

I have a bit of an odd question. My fun car is a Ford 4.0litre Straight 6 twin turbo Falcon. The current turbo setup is twin R33 N1 GTR turbo's, now I am looking at upgrading and below are my listed options.

GT2860r -10

GT2660r -5

Hi flow the R33 N1 turbo's (questionable)

Now my problem is that I get fully boost @ 2200rpm which is great, but I want more top end and I don't want to lose much of the response.

So my questions are which of you guys have the following upgraded turbo's on your vehicle/s, when do you get full boost?

Is your engine stroked or stock 2.6?

Cams?

So basely what I am trying to work out is for "example" if someone gets fully boost on a stock 2.6 GTR with R33 N1 @ 4500rpm and with the same setup someone gets full boost using GT2860r -5/-10 @ 4700rpm, that's 200rpm difference give or take. Then you add 200rpm onto my 2200rpm = 2400rpm full boost......Winner!!

Keeping in mind I know that this isn't as simple as it looks, it's just to give me an idea. Also I have searched the forums with some results, but nothing that would make my mind up.

Thanks.

Edited October 1, 2009 by Revenge

[R31Nismoid]

What is full boost?

I love that statement 10psi? 20psi? what?

Going from GTR N1's to -5's is (at a guess) what you are after.

They spool a bit later than N1's, but make near on 100rwkw more give/take. Your probably talking.

So you'll make 400rwkw without much of a worry... 33 GTR N1's aren't the best turbo either, bit laggy so they would spool maybe a tad earlier than -5's, but not by a lot.

32 N1 are dreadful

33 N1 are not too bad

34 N1 are the best of them all (simlar to a -9/GT-SS turbo), so 330rwkw with pretty good response.

I mean on my 2.6ltr im making boost in the 2000rpm range and under load 3300rpm im making i think 15-16psi on GT-SS's (hard to tell, my 20yr old gauge is not so good)

IMO the -10's are too big... Unless you are after 450rwkw+ then they are not what you want to look towards. If you are after that kinda power then ye, go for them but they will be noticeably laggy compared to N1 turbos.

[Revenge]

What is full boost?

I love that statement 10psi? 20psi? what?

Take your pick 10 or 15psi "full boost" @ 2200rpm regardless

[Guilt-Toy]

will the coon block be able to handle that much power?

my mate used to be into the boosted fords.. actually he still is. and he had big issues with splitting the blocks. he has split many of them

good luck with it though. maybe 2 x rb25 turbo's would do you some good?

can you upload some pics of your car, im interested in checking it out

[Revenge]

will the coon block be able to handle that much power?

my mate used to be into the boosted fords.. actually he still is. and he had big issues with splitting the blocks. he has split many of them

Which falcon block/s are you taking about? The ford block I am using is 1989-1994 SOHC not the newer Barra engine. AU blocks are crap. You can make around 700bhp (stock internals) give or take depending on your tune keeping in mind the 4.0 block can split around the dizzy so you wouldn't run that amount of HP all the time.

[bradsm87]

All those turbos are too restrictive in the turbine housings for a 4L engine IMO. I'd go with twin GT2860RS .86's. It's similar to -5 turbos but more free flowing on the exhaust side. A lot more free flowing without choking things up. U can wind in a lot more timing and gain a lot of the response lost back. Also u can make more power on lower boost so better on the engine.

Edited October 1, 2009 by bradsm87

[Marko R1]

without a doubt i'd go for the -10's!

im talking from experience, naturally, dont trust everything you read on these forums.

i have these on my gtr which is running a 3.0ltr & its awesome...does not feel laggy what so ever, the exact same opinion was exchanged with my tuner.

in fact, it feels more responsive than when i had my -5s on my 2.6ltr & a lot of ppl here rave about this package & how good the response is (which it is).

to put it simple, my new setup is a torque monster...now imagine this setup on a 4ltr bottom end?

[Revenge]

Thanks for the info everyone, I also agree with you Marko and so does my tuner. I just got off the phone with him and -10 are the way to go with minimal lag. I should have really contacted him first before posting on the forums, but I wanted some personal experiences and individual opinions.

My quote so far for -10 is about $2600 a pair I didn’t ask about actuators. Good price??

[Marko R1]

speak to daniel @ mtqes.com.au and tell him that marko sent u.

i cant advertise what i paid for my -10s but it was significantly less than what u quoted

[Marko R1]

out of interest who is ur tuner?

[Revenge]

out of interest who is ur tuner?

Motsons.

[Revenge]

speak to daniel @ mtqes.com.au and tell him that marko sent u.

i cant advertise what i paid for my -10s but it was significantly less than what u quoted

Thanks Marko will send him an email or call.

[BLSTIC]

*too big*? Remember the falcon engine is really stressing itself revving past 5500rpm... If you work out how much air the engines flow (as in litres*rpm) they are probably pretty similar.

[James_03]

will the coon block be able to handle that much power?

It's funny cos it's true. Saw a boosted EA at a local dyno one day getting it's first run.

Threw a rod at like 7psi lol.

But to get on topic, I have the -10's currently on my rb30dett and there sweet.

Another vote for -10's.

[Marko R1]

I have the -10's currently on my rb30dett and there sweet.

Another vote for -10's.

another dirty thirty with -10s

what power is it making & at what boost level?

[Guilt-Toy]

Which falcon block/s are you taking about? The ford block I am using is 1989-1994 SOHC not the newer Barra engine. AU blocks are crap. You can make around 700bhp (stock internals) give or take depending on your tune keeping in mind the 4.0 block can split around the dizzy so you wouldn't run that amount of HP all the time.

he was using the late model xf blocks... so its a bit older then yours. but i am sure the falcon engines are not very strong for forced induction. they were just not built for this kind of punishment.

[Revenge]

It's funny cos it's true. Saw a boosted EA at a local dyno one day getting it's first run.

Threw a rod at like 7psi lol.

But to get on topic, I have the -10's currently on my rb30dett and there sweet.

Another vote for -10's.

I would probably look at the tuner........

[Revenge]

*too big*? Remember the falcon engine is really stressing itself revving past 5500rpm... If you work out how much air the engines flow (as in litres*rpm) they are probably pretty similar.

That's complete crap "too big" also a built falcon engine can rev to 6000-6500rpm no worries. Standard form around 5500rpm in the old SOHC, 6000rpm in the newer Barra DOHC setup. Air flow wise a falcon @ 5000rpm for example pushes more air then a 1JZ @ 7000rpm maybe even a 2JZ.

[Revenge]

he was using the late model xf blocks... so its a bit older then yours. but i am sure the falcon engines are not very strong for forced induction. they were just not built for this kind of punishment.

The thread really isn't about how strong a falcon block is or isn't, but I will go with it for now. Big turbo falcons have been built for years will staggering straight line performance, massive amounts of torque, user friendly Hp and with the correct tuner and knowledge a standard block can do this. The SOHC 3.9-4.0litre has been getting turbocharged since 1989 around the same time as the Nissan GTR Skyline, falcon's even had a factory turbocharged option using a company called A.I.T, now I can date this even further back around 1983 Ford released a Falcon Grand Prix XE turbo model which used a 4.1litre xflow engine (push rod) and in 1988 Ford released a twin turbo A.I.T Falcon. So unfortunately your comment regarding "but i am sure the falcon engines are not very strong for forced induction. they were just not built for this kind of punishment" is incorrect as Ford has a history of turbocharging falcon's it is just a little unknown unless you are a Ford enthusiast.

[JiN_MaN]

boy the thought of having a 4L twin turbo its a huge difference from 2.6L, What kind of power are you currently running?