WREXY

I have a TD05/06 20G in my possesion to fit to my 2litre MY00 turbo over my VF23. Looking for around the 380 horsepower mark.

Having read a bit on the MD321H, I now wonder if I'll be better off with a one. I know they both make similar power, but driveability is very important which is the reason I'll be going for a STI 8 TMIC over the FMIC I had purchased. The question is, will I enjoy the car more with a MD321H over the 20G? Will it be more responsive with less lag than the 20G?

911

Call Mark at Lateral or Paul at Zen, or AndyF.
Can depend on several other factors/supporting mods from what I've read.
I have the 20g on a warm 2 litre and lag is not great at all, you drive to the turbo's characteristics.

Andy.F

I don't find the 321 any more responsive than a 20G but it will make more bhp and is capable of higher boost on the same set up. Probably a 20 bhp step up from the 20G.
The response on either turbo is influenced considerably by the intercooler/headers/uppipe and turbo intake pipe.
A recent Sti8 improved from 1.5 bar at 3800 rpm to 1.8 bar at 3500rpm just by changing the uppipe and intake pipe, this was on tubular headers, FMIC and a 321H.

Power Junkie

iTrader: (1)

I was supprised at the size of the MD321H Its not much bigger than the VF28, does look good though

911

Only 20 bhp Andy from a 20g? You surprise me!

I have to say that the 20g I have is from Andy along with the mapping, and my stock Sti + these and other bits is a great '360/370 ish' engine.

Andy.F

Its quite difficult to rate turbos as every installation is different and will result in a different result. The interesting one for me is how the 321T is responding on a 2.0 AVCS engine, just had a very nice result on one of those, earlier spool than I was expecting

Power Junkie

iTrader: (1)

Have you tried on a non AVCS 2.0?

Lateral Performance

iTrader: (20)

Graham,

The MD321H consistantly makes 400bhp at circa 1.4bar, but turn the boost up on the "H", and you'll get more power !!!

As Andy has said, the headers/up pipe, intake pipe combination can have a dramatic effect on the results. We know what works very well, but people often have parts already, so it can be a little difficult to get the best results every time.


I have no doubt that Andy will see even better results with the "H", as he maps different set ups. Other certainly have


Mark.

Power Junkie

iTrader: (1)

What can the MD321H be turned up to (with supporting mods)
In your opinion what is the best headder + uppipe combo for it for a Classic STI?

WREXY

Good question. With the 20G I was going to stick with the stock headers ported and the stock intake pipe to minimise surge. Is this not the best combo with the 20G?

I'm interested in Graham's question too.

CYP_ROCK

STI 7 Andy.


JAC

Andy.F

I assume you are referring to spool up here as you seemed quite surprised how much power we had achieved so far, I wasn't aware of any others that were higher ?

Regarding maximum boost, that will be dictated by the engine rather than the turbo in most cases, on my own car I have wound the T up to 2.4 bar and just clipped 600lbft of torque from the 2.5. I think Jacs std unopened Sti7 made just over 400lbft at 1.7bar on the H

911

My 20g/2 litre is on stock engine (Sti V3) and gruppe S headers/helix up-pipe/FMIC and a decat 3''/ large cone filter inlet, but is is a fab engine seemingly unburstable and full of mid/high end sparkle right to 8000 from 3500.
Andy mapped 1.6 max on V Max+NF full dose.

It will be a shame to strip it for a 2.5 build, but I need alot x alot for hillclimbing where 500+ is becoming the norm (average realy) and I expect to have an MD? on it to get there as 400 is the 20g's top limit.

Andy.F

Again, beware of comparing numbers, I know of 3 cars that have achieved over 435bhp from a 20G. Fuel octane was a big player.
Your header/uppipe combo is almost optimum for your intended use, from recent testing I have been doing, I'd even suggest going down on size again on the uppipe to a std/ported one and matching it to the tubular headers.
The Garrett hybrid will make over 400 on most set ups but not sure I'd recommend a seasons racing at this level on std internals.
Different for a road car or for someone chasing dyno numbers that doesn't continuously run it hard. A 20G is already capable of pushing std internals close to their limits.

frayz

iTrader: (7)

Will that be run like that all the time Andy?

Is that not at the limit of the STI 7 internals or will they take more?

Andy.F

No, he has just increased it to 1.8bar lol

Yes that is slightly above the limit that I would recommend although I have ran more torque/boost on a JDM 2.0 without issue.
In this case the customer is aware that he is living 'on the edge' as I see it.

Andy

Barnesy

Looking at this spec for an 03 sti (uk).

20g turbo, aps cai, walbro pump, gt spec headers, 3 inch decat, apexi avcr and Andy F remap.

Which would be the better, the uppipe that comes with the gt spec headers or standard?
What would the differences between the two be?

Thanks
Stuart

Ian

iTrader: (10)

think you need to use the up pipe that comes with the gt spec headers, as they are held onto the manifold with 3 bolts, and the standard one has 2 bolts

911

Good thread this.
I am expecing a strong torque curve that is wide and flat from a steel 2.5/8000 rpm capable with the headers/up-pipe and a suitable MD.

I am very keen to get a gutsy engine from 3500 right through to 8K and quite willing to change the headers to get it, but i think i will be ok.
I'll be sad to see the trust 20g go though!

Can you run Vmax alone without NF at these levels as I'm told there is to be a big clamp-down on funny fuels in hillclimbing in 2008 on. (ie Road going cars after 1999 registration must run cats if they were originally fitted, so that is just the start of it).

unfeasablylargegonads

iTrader: (3)

Andy mentions going smaller/using the standard up pipe, I am wondering how you mate your standard up pipe to 3 bolt headers or are there smaller diameter up pipes with the 3 bolt fitting availibe, if so where from?

CYP_ROCK

No, he has not increased boost at all, its still 1.75bar as you maped it.
I just love it on the edge. You only live once

JAC

Northern Nick

iTrader: (1)

Talking of standard up-pipes and tubular headers to get better spool, how would a veturi up-pipe compare with the standard up-pipes for spool.

I'm going, maybe, to fit a afp5-20g to my UK STi V7 and I'm hoping for the same torque low down (1000rpm-3000rpm) as the VF35 but when the VF35 kicks in, I kinda want the 20g to be lazier and gradually build the torque/power up as I find the VF35 very agressive to drive. I seem to be going up through the gears as as soon as I'm ready to change gear (between 2500 & 3000rpm) on a steady drive, the turbo has just bounced from about 0.5 to 1.5bar boost making for a difficult drive.

If I want to drive fast, I'll rv the little b*gger but when I've got the wee boy in, I dont want nothing to huge torque in 500rpm.

911

The response of my 20g is not sudden at all but builds strongly with a smooth 'spool' and then hangs on for ages.
Mind you, Andy mapped it!

Barnesy

bump

Northern Nick

iTrader: (1)

And I'm sure Andy will map mine again

I hope

I think the 20g is the right turbo for me reading the posts I've read but when the question is asked:

Whats it like to live with day to day?

You dont get owt back just woundering why

380+lbs/ft would be nice though

Power Junkie

iTrader: (1)

We will be getting some good Idea of this soon, Andy will be up mapping our cars on the 12/13th nov, there will be 2 RA's with 20G's and My Type R with a 321H. so we should be able to see how they do against each other.

Northern Nick

iTrader: (1)

Sounds interesting

Power Junkie

iTrader: (1)

It should be, they have much the same mods done too.

Andy.F

Nick

The car can be mapped to have the turbo coming in as hard or gradual as you like. There is an 8x8 table of throttle position against RPM Vs target boost, so if when you apply 1/2 throttle, if you only want 1/2 boost, thats what you can have.

Usually they are mapped to come in as soon as possible but it doesn't need to be that way.

I'll send you some power graphs of VF35 V 20G on a new age Sti.

Andy

dynamix

iTrader: (3)

interesting thread guys

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