Andy,

The "T" is finalized. It remains a circa 450bhp on V Power turbo, but with much improved spool up.

The "H" has yet to be finalized. We've had some very good results, but I feel I can do better. I have another version being tested on my car today, but I came up with another idea, so I'll need to try one more, before I make my final decision.

We are still testing different versions of the "V". I was expecting the last version to spool about the same as the non billet, but flow more. It did in fact spool up several hundred RPM earlier, but didn't make as much extra power as I'd expected (515bhp on V Power) but we're pretty sure why.


The version I expect to be the final spec' will remain at circa 500bhp on Vpower, but will spool up even more quickly.


And then there will be a new version, aiming towards 550bhp on Vpower


There are up grade options for the H, T, & V, depending on whether the owner is looking for more power, or better spool up.


More will be posted.


Mark.

 

How much improvement has the billet T gained compare to the non billet T?

 

I have to say I was well impressed with the spool on the billet T on a 2.0. I have always been a fan of the T on a 2.5, I've been using one on my own 2.5 Spec C for a number of years now however I always found them a bit 'sleepy' on a 2.0. You could ofter get caught out in the wrong gear and have to shift down unexpectedly in order to wake it up! Not now with the new version, works really well on a 2.0.
Mark will tell you, I have always said I wouldn't swap a 20G for a T on a 2.0 for road use......I would now happily make the change to a Billet T as it doesn't lose out on response. As for power potential, maximum airflow volume seems similar to the original T, it may make more but I have not done a back to back on the same car to verify that.

Edit to add, don't go too big on upipe diameter, this will kill the spool and gain you nothing at the top end. I think Abbas's car had a Harvey Smith tapered uppipe on there and it worked well. Having tried many other options, I went back to using a lightly ported OE uppipe on my T on the 2.5

 

Sounds like good stuff. What headers would you recommend along with the Billet T on 1 2.0l JDM STi? Also would it be worth sticking to a 2.5" downpipe to help the spool?

 

All cars are slightly different but on your car with the higher rpm limit you may get worthwhile benefit at higher rpm from a set of tubular headers as long as the uppipe is small bore.
I use a 2.5" full system on my T which runs at anything from 460-500bhp depending on fuel mix. I tried a number of 3" systems and swapped back to 2.5 for the improved midrange. Note however that my 2.5" system is a H+S which uses proper mandrel bends that maintain full bore with no crimping, also the silencers are a true 2.5" bore throughout.

 

Currently got 1 piece equal length headers, which I am not to happy with performance wise. I also have the H&S 3" catback tappering down to a 2.5" TSL gas flowed downpipe. I was going to swap the DP for a 3" to allow abit more top end however i fear the loss of spool. Previously i had a Ganador exhaust system, which had a built in baffle (1.8" baffle built inside the backbox) which allowed alot of back pressure & the spool was amazing!

Currently I am thinking about the new billet wheel, unequal length headers & some sort of a back pressured exhaust system but I am concerned about any restrictions it may cause at this level.

 

Could always buy your titanium Ganador back

 

Any graphs for the billet T on a 2.0 please

 

I miss that exhaust truely. Light weight & amazing build. Thanks to that someone, who put the idea in my head that it was causing a restriction!

 

I have to ask Andy, do you think you have enough data to give any definitive answer to the obvious question on peoples lips ?
Billet 321T or SC46 ?
And Merry Xmas BTW

Martyn

 

Short answer - No I'm afraid not Martyn. Mark asked me to do just such a test on my own car and I'm sure Kev would be up for that also but with the race car taking up all my free time, its just not going to happen any time soon.

Merry Xmas

 

Best of luck with the race car m8, would love to have the time to get near mine to work on it, lol.

Martyn

 

Hmmm, you must be too young to get that work/life balance thing sorted out in your favour yet !

 

Can't argue with that m8 !
Righto, I'll not post any more chit chat on Mark's thread so maybe we'll catch up by phone next year.

Martyn

 

Makes for interesting reading Andy.
I was *almost* sold on building a 2.5 with a "T " but since i already have 2.0 cdb's lying about it's good to hear how well the new billet version is suited to the 2.0.

Plus, if it goes as well as you say, it'll save me money in the long run since there will be no need build a 2.1,2.5 to make better use of the turbo...

cheers
F

 

It's a common misconception that it costs more to build a 2.1 than it does a 2 litre. If you are buying a new crank anyway which I'd assume you are, then it becomes no more expensive than converting the block to rear thrust, £125.
Rods, pistons, gaskets, oil pump, bearings, studs all cost the same either way.

Martyn

 

Does it make that much a difference Martyn going 2.1 over the 2.0?
My initial plan was to fit a stroker kit but was advised due the extra cost involved going 2.5 was a better option, bang for buck etc....

Not too convinced about the 2.5 for the long term tbh hence interested in what Andy had to say about the billet T on a 2.0.

cheers

 

Dan,


Going 2.5lt is the more expensive option, unless you already have a 2.5lt block, and it will also be a much weaker engine, unless you spend a lot of money re-linering.

And if you're going to do that, you'd be better off looking at a 2.35lt.


The 2.1lt is very good VFM.


Mark.

 

I think a 2.1 on a billet T with a nice small bore uppipe would be excellent. At circa 450bhp the reliability should also be as good as it gets.

Dan, speak to John Felstead, he went 2.1 on his JDM Sti and although the numbers don't tell the full story (torque up around 5%) the car feels much more responsive at lower rpm and the turbo will spool even earlier.

 

What is the spool up differance between the billet T and the non billet T on a standard newage two litre sti to max boost ?

Andy

 

Yes it absolutely does, the off boost driving experience is very different as is the transient response. You'd be forgiven for thinking you had a much bigger engine than the 100cc increase would give, but of course it's all down to the stroke.

 

Been driving my car on the billet upgrade for the past week. Not yet mapped in until next week so taking it easy.

Even without putting my foot down you notice a difference already!!! Even the noise via the DV/delete sounds different to before.

Cannot wait to get it mapped on V - Power and then maybe try a splash of meth for results.

Thanks again Mark for your help and putting up with my calls.

Steve

 

Here is our one on 2.1 stroker and mapped by Duncan@RaceDynamix

Nothing more just amazing to drive,Mark your turbo is just amazing on 2.1,really pleased and pleased too with Syvecs S6pnp

Again big thanks to Duncan@Race Dynamix for mapping and Slowboy Racing for great job on our car






Jura

 

Hi Jura,

A few questions please:
I assume this was mapped for stright V-Power?
Do you have the new billet T or a old MD321T with the compressor wheel upgraded to the billet version?
Could you post you power and AFR graph if you have it as well?

Thanks
Richard

 

Hi Richard

Yes this has been mapped on straight V-Power,no methanol or NOS.
No this is new billet T,which we are bought from Mark@Laterl Performance
At moment don't have power and AFR graph,i can ask and will post later on

Jura

 

Thanks Jura ... nice figures BTW .... I'm sure it is fantastic to drive on the road.

 

now that is some good power at a nice boost level not a stupid boost level like alomst 2 bar and on v power , i wonder what woudl happen with meth and touch more boost humm well done nice to see boost tgraphs as well

 

This is my JDM STi, 2.1 litre using stock VF37 turbo, Stock TMIC, Stock Injectors, Stock airbox, Stock everything external basically with a Milltek 3" exhaust and Tracktive EcuTek remap.

Car makes for a great midrange, road and short circuit sprint setup. Engine was built with a 9.1:1 compression ratio. Engine has two maps, one for a 33% race fuel mix for sprints, other is pure v-power for the road.

Torque of 400lbft @ 3500rpm is where you see the 2.1 advantage, power isn't the thing you will ever see from this setup, the turbo is too restrictive. Going to a bigger turbo would up the power significantly, it would have to be an exceptional turbo to match the response though, which is always the compromise you are trying to juggle.



P.S ignore the squigly bit post peak torque, it pulled a bit of timing out on the rollers, it doesn't do that on the road which is where it was mapped.

Just an interesting comparison for you.

 

Our wagon has been again mapped by Duncan@RaceDynamix on 20% methanol and here are results:


BHP and Boost



Bhp and torque:



Bhp and AFR:



Jura

 

great stuff,im glad you finished it in the end.