Hi,

I have just taken delivery of my new turbo kit which is a T51R SPL BB turbo.

What i need to know is my mate has just offered me a pair of T04R cutbacks 0.81 turbos in exchange for the T51.

Will i get more horsepower using 2 'smaller' twins in a non-sequential setup or with the single T51R. Also which would be quicker down a drag strip ?

i was gonna run the T51R @ 1.9Bar ish - would running twins at a lower boost get more power ie 1.5Bar ?

Regards

J

 

Wow twin TO4R's would be insane. I just put one on my car. I don't think that a twin setup like that would ever spool. Stick with the T51R, especially because it is BB.

 

IGY runs twin TO4S's... Not sure what R's would do..

 

too big ?

Hummm i wonder if IGY can shed some light on the subject ?

Im looking for 700+ rwhp to go drag racing -

The R's have the same a/r i think at 0.81 - so they may spool a little slower -

im running anti-lag using the motec ecu - so lag might not be too much of an issue.

this is the spec of the T04R

HKS T04R - 650-700 PS Output

COMPRESSOR:
-Wheel- 63 Trim - 66.7 Inducer / 84.0 Major
-Housing- 100 Inlet / 60 Outlet - 0.70 A/R
TURBINE:
-Wheel- 76 Trim - 74.2 Major / 64.7 Exducer
-Housing- T04 inlet / 65.75 outlet - 0.81, 0.96, 1.15 A/R


And the T04S

HKS T04S - 550 PS Output

COMPRESSOR:
-Wheel- 60 Trim - 59.0 Inducer / 76.2 Major
-Housing- 100 Inlet / 60 Outlet - 0.70 A/R
TURBINE:
-Wheel- 76 Trim - 74.2 Major / 64.7 Exducer
-Housing- T04 inlet / 65.75 outlet - 0.84, 1.00 A/R

The only difference being the compressor wheel.

Any ideas - they are nice turbos - but i need to say yes/no before i do anymore work to the engine

Regards

J

 

Well... If you can make the motor handle it... One single TO4R can make damn near the power you are looking for. I've seen ~700 on mustangs. Just need the right build and the right tune and a SHITLOAD of boost.

 

i am getting the motor built with:

Monster bridge ports
3mm 1pc ceramic apex seals
motec ecu
whole engine cyrogeniced
motec ecu
HKS dogleg box
uprated LSD
HKS twin plate
etc
etc

it should hold 2 T04R @ 1.5/1.75 bar - this will be used for drag mostly - some circuit racing too.

J

 

Im not sure that twin T04R's would spool at all quick enough for drag racing. if you were to go twins you should think about trying to find some slightly smaller like say twin GT35's or something to that effect so that spool times would be decreased and would still provide huge amounts of boost when needed. Just a suggestion however it seems you've done your homework and know what you're talking about. Sounds lik it should be pretty fast though let us know how it turns out. cheers

 

Hi Salamanzer

I have pondered this question for hours upon hours in my own case.

I decided in the end to go with a T51 (72mm comp wheel) and large turbine set up. The reasoning behind this was mainly packaging the set up in an engine bay and respect for heat issues and flow of charge plumbing etc.

The big single is a far better technical solution, you can make 850bhp (740rwhp) easily with this turbo while respecting the "book" operated limits (turbine speed) or you can make near 1000bhp or more if you realy push things like crazy (Turbine speed around 110 000 rpm , "has been done") The 72mm turbo will allow this over speed and give you real nice boost responce with stacks of power.

With a real nice manifold and divided rear A/R you can harness the 180 deg split in power pulses on the 2 rotor to decrease turbine spool time. The HKS T51 version does not use this principle so you may want to buy the genuine Garrett version with divided rear.

In regards to your gearbox choice, you may want to consider using a Guru dog box (made here in Australia) they are stronger than the HKS versions from what I have been told and seen from using them. I am pretty set on running one of these in my machine

To finish off the twins would be great too but just getting it all in there is the obstical you face, maybe you will get a reply from someone who has given it a go ? I can close but decided against it

 

After reading the thread about the guy running 32 psi and now this, i am beginning to think that us RX7 owners are sniffing way to much exhaust. Arent we satisfied with the 500 rwhp benchmark anymore? Im at 403 and its insane as it is on the street. I want more power but, i almost am possitive that i wouldnt be able to handle it.
adam

 

Ah - im a HKS dealer so everything i use has to be HKS because its also gonna be my demo car.

So the T04R's are too big and slow to spool - the T51R is too big and slow to spool ----

err,

im just thinking that i can get away with having a larger turbo by using the motec's anti-lag which means i will have positive boost at idle ....

In terms of power - i would be better off with twins would i not - i could also use a lower boost with the twins ....

i think that the twin T04R's maybe a good project - and the lower boost levels should help with engine stress levels -

i was hoping IGY might pop in and have something to say about his T04 twin setup .... maybe he can highlight some of the problems hes had and some he has solved.

J

 

I say go with the twin T04R's and spray a wet 100 shot, that well definatly help with any lag issues

STEPHEN

 

twins would be neat if you could get them to spool. Wouldn't be less stress to go with a single due to the anti-lag swich and the heat that the twins would give off? Have you considered a 3 rotor Salamanzer with the twin setup, it would make the project that much better?

 

yo mean a 20b engine ?

Yeah maybe....

but why go triple rotor -if your spending the money go for a 4 rotor - that would be a sweet drag engine - NO NO NO must resist ...

No it has to be a twin -- yes a single would be easier but now im thinking a lower boost level will allow for more power in the long run --

The T51R is rated at 1000 BHP
The T04R is rated at 700 BHP

i should make a better HP figure using the twin T04R's at a lower boost pressure - it also gives me some leway for later improvements ....

They both cost the same in real terms ---

Also the twins should give more torque at lower rpms as there wll be more boost pressure ---

i hadnt thought of using nos - the water injection should help with cooling the inlet charge at higher boost pressures -

i could also try adding methanol to the fuel to increase the cooling effect.

 

Yes, a 3 rotor may be in your best interest for twin t04r's! On a 2 rotor you would need some serious porting and a big shot of nitrous to spool those...

I think the T51 will give you everything you want.
its a monster of a turbo

 

if your an HKS dealer...what do you think is a better turbo for the FD...T51Rkai/T04R

 

with that in mind i think that i will stick with the single - it will be easier to setup too.

So i will keep the T51R -

so things are back to track - looks like my mate will just have to go and buy his own single

Ok then - just gotta order the last bits ----

so hopefully mid jan early feb the car should be finished...

J

 

I'd stick with the single as well. It can make the power you intend to, easier packaging and all that stuff, and will spool quicker than the twins.
I'd probably throw on a decent shot of nitrous as well to really get things cooking in a hurry.

20B because it can make more power than a 2-rotor and 4-rotor is illegal in almost all of professional import drag racing bodies and respective classes.

If you are shooting for 700 or so rwhp, then definitely stick with the 13B.