I'm running an Andy Forrest TD05 20g on my '96 classic and had it dyno'd yesterday at Zen Performance where it made 350bhp/323lb/ft - boost was 1.5 bar but dropped to 1.2 bar above 6000rpm. This was with a new actuator fitted to try and hold 1.5 bar above 6000rpm but it's still dropping off.

I'm interested to see what power/boost other people have got with their 20g's and what spec so you are running to support it,so post them up :thumb:

740cc injectors a bit too big but gives me a better scope for the future
i have built 2ltr block with forged pistons and sti 9 rods,
groupe s header heat rapped
blitz filter
apexi PFC
apexi avcr
autobhan front mount
zigen s/s
decat
fuel presure regulator from lateral performance
Tdo5 20G purchised from lateral perfomance
oil cooler
oil breather tank
reverse inlet manifold parrelel fuel rails
All put together and mapped by Neil from Slowboy racing
runing 10% meth and 90% shell v power
i dun 4 runs and it was all consistantley over 400 bhp with highest been 402bhp with 365 tourque all at only 1.5 bar. On the road it gets to about 1.7 bar and it spools up so quick. could of got a lot more but the intake Temp was too high according to the guys at Dyno dynamics at luton. the car is back at Slow boy racing to move the induction kit to the wing on a classic with direct cold air feed il posting the results when all dun.

i didnt change my actuator and my car holds boost fine il have acces to a scanner later this week and il post my graph.

thats very low figures uve got there i take it ur still runing a standard engine?>???

thats very low figures uve got there i take it ur still runing a standard engine?>???

That's what I was thinking !

My full spec is here:

STI RA V-LIMITED ENGINE-Closed deck block,under piston oil squirters etc
Andy Forrest TD05 20g Turbo
Carl Davey refurbished red inlet manifold
Carl Davey inlet manifold insulators
Carl Davey head tank insulators
Custom made parallel fuel system
300zx TT Z32 Maf
GT SPEC GEN II ceramic coated headers & upipe
550cc injectors
hybrid FMIC
apexi power fc and commander
apexi power fc boost controller
sx fuel pressure regulator
walbro 255 fuel pump
straight through s/s exhaust,hayward and scott
K&N 57i induction kit

Mapped by Jolly Green Monster.

I should add that I still have a 90 degree inlet on the 20g rather than front entry but Andy Forrest said that I shouldn't lose much power due to this.

Paul@Zen said if I can get the boost to hold 1.5 bar above 6000rpm then I may see 370bhp.

From my spec then,what power would you expect ?

im not profesional it may be a good idea to get one of the tuners on here to shed some light, one thing i can assure u is dont chase dyno figure and figures can very between dyno to dyno depending on make of dyno, shoot mode,tempreture and mapper.ive raced an s13 thats are runing 450 bhp but it only has 450bhp for a split second as it only reved to 7200 u mite line up next to me and u mite just blow my doors off LOL it all depends on the driver and how the car is setup and bare in mind on the road you will be runinng more power. simon jolly green monster is very very very respected in the mapping so im sure there a reason to why your car is only runing so much power.

The biggest issue is with the boost dropping off. I originally thought the actuator supplied with the turbo from Andy Forrest was weak so got another one from him but it still seems to open too early.

Paul thinks an uprated actuator could prevent the boost from dropping off so I need to look into that.

353bhp / 354lbft (deltadash road dyno) on a new-age wrx with the mods in "view my scooby". It holds 1.6 bar up to the redline.

Initially I felt like, what, only 353 bhp, but it goes like stink anyway so I'm over it. I've got quite a nice power band now IMO and 354lbft is not to be sniffed at.


Edit: my exhaust is 2.5"

353bhp / 354lbft (deltadash road dyno) on a new-age wrx with the mods in "view my scooby". It holds 1.6 bar up to the redline.

Initially I felt like, what, only 353 bhp, but it goes like stink anyway so I'm over it. I've got quite a nice power band now IMO and 354lbft is not to be sniffed at.


Edit: my exhaust is 2.5"

Yeh,mine goes very well on the road but it's abit disappointing to only see 350bhp on the dyno when I wanted around 380bhp when I built it !

I know exactly what you're saying, I felt the same :)

Bear in mind, that the WRX heads will not flow as well as the STI heads and therefore will not make as much power as an STI would with similar mods...

350 on the dyno ur propberly getting more on the road.the Tdo5 20g turbo is a very good turbo it produces figures from 350mimum to 380bhp. but when u add meth octatne booster u can get up to 440, i think andy forests own car was runing 440 or 430 not 100% sure.

but that was years ago

Mus your's on the Road dyno when it hit normal boost showed around 430ish atf as well....

i am aware of that but how reliable is the road dyno maybe start a new thread what was the make of the road dyno???

so there is massive diffrence between sti heads and wrx heads.

i am aware of that but how reliable is the road dyno maybe start a new thread what was the make of the road dyno???

Lol, Regardless of figures your car drives as if it is in that power band.
402 on the DD remember only peaked at 1.5, it didn't even hold that boost to the end.
I think it was at around 1.3ish near the tail on the dyno due to cooling....

On the road it peaks at around 1.7 and easily holds 1.5/6 to the end...

Lol, Regardless of figures your car drives as if it is in that power band.
402 on the DD remember only peaked at 1.5, it didn't even hold that boost to the end.
I think it was at around 1.3ish near the tail on the dyno due to cooling....

On the road it peaks at around 1.7 and easily holds 1.5/6 to the end...



you keep talking like that ur injecting too much confidence me, i feel like i can enter TOTB :lol: na js messing im more than happy with the way it drives how would u compare it to your old spec on the 18g???? and when is the bullet coming out???

I had a 20G on my 2.5 uk with standard heads that made 336bhp @ Powerstation rollers a few years ago. This was on 1.2 bar flat across the rev range. It was then remappped to 1.55bar and though it was never RR it was a much quicker car than at 1.2bar.

I would of thought you should see 380bhp at 1.5-1.6bar from a 20G

I had a 20G on my 2.5 uk with standard heads that made 336bhp @ Powerstation rollers a few years ago. This was on 1.2 bar flat across the rev range. It was then remappped to 1.55bar and though it was never RR it was a much quicker car than at 1.2bar.

I would of thought you should see 380bhp at 1.5-1.6bar from a 20G

Yeh 380bhp is what I had in mind so 350bhp is abit low for me :confused:

It is on the low side.

340ft/lbs of torque here on an old 16g@1.5bar dropping to 1.2bar.... and far less mods.

Best to ask the dyno operator and your mapper on the best way forward.

It is on the low side.

340ft/lbs of torque here on an old 16g@1.5bar dropping to 1.2bar.... and far less mods.

Best to ask the dyno operator and your mapper on the best way forward.

Yeh I had 320ft/lbs of torque on my old 16g@1.45 bar on the wrx engine and now have the same as that on the Sti engine and 20g :cuckoo:

Nobody seems to know why it's low or why it won't hold boost above 6000rpm !

you keep talking like that ur injecting too much confidence me, i feel like i can enter TOTB :lol: na js messing im more than happy with the way it drives how would u compare it to your old spec on the 18g???? and when is the bullet coming out???


:lol1: You should be happy it is a bullet in the making!... ;)

It spools near enough identical to my okd spec, but just pulls so much harder at the top, it just wants to keep on going... You should be able to see a midd 11 with that at the pod...

With regards to the Bullet, just watch this space.... ;):D

Here's my graph from Zen - What do you guys think of it ?

http://i2.photobucket.com/albums/y11/clarkyM3/ZenDynoGraph.jpg

I dont quite get the BOOST DUTY RAISED bit as it looks like less power?

I dont quite get the BOOST DUTY RAISED bit as it looks like less power?

Paul just tried that to see if it would hold the boost higher but it didn't.

He said it probably made less power because it had been run a few times and was getting hot.

Here's my graph from Zen - What do you guys think of it ?

http://i2.photobucket.com/albums/y11/clarkyM3/ZenDynoGraph.jpg

It seems like your car is really flat low down? Was the run started "from low down", so to speak, or was it from 3500 RPM onwards?

For comparison, here's my delta-dash: http://www.bilar.co.uk/subaru/graphs/jgm-2007-05-13.jpg

Mine makes 200lb/ft by 3000 RPM and your one seems to be making it at about 3750 if I'm reading the graph right? It's dropping off quite quickly as well after the torque peak... Is your exhaust blocked? :)

It seems like your car is really flat low down? Was the run started "from low down", so to speak, or was it from 3500 RPM onwards?

For comparison, here's my delta-dash: http://www.bilar.co.uk/subaru/graphs/jgm-2007-05-13.jpg

Mine makes 200lb/ft by 3000 RPM and your one seems to be making it at about 3750 if I'm reading the graph right? It's dropping off quite quickly as well after the torque peak... Is your exhaust blocked? :)

The run was started in 4th gear from a low speed if thats what you mean ?

Paul did say it seemed quite laggy although I don't think it's too bad on the road.

From 2003 on 98RON Optimax (pre V-power). MY99 2.0 on aftermarket headers. With a change to std ported headers it made something like 350 odd bhp and 320-330Ib ft torque but felt a lot quicker cause it spooled up a lot quicker. Was nicer on the road with the std headers.

http://i36.tinypic.com/2rymxl5.jpg

Meant to add that was with 1.4 bar across the board.

From 2003 on 98RON Optimax (pre V-power). MY99 2.0 on aftermarket headers. With a change to std ported headers it made something like 350 odd bhp and 320-330Ib ft torque but felt a lot quicker cause it spooled up a lot quicker. Was nicer on the road with the std headers.

http://i36.tinypic.com/2rymxl5.jpg

Meant to add that was with 1.4 bar across the board.

Looking at your graph i've just noticed that mine has the same power at the wheels as yours does :wonder:

I'm running an Andy Forrest TD05 20g on my '96 classic and had it dyno'd yesterday at Zen Performance where it made 350bhp/323lb/ft - boost was 1.5 bar but dropped to 1.2 bar above 6000rpm. This was with a new actuator fitted to try and hold 1.5 bar above 6000rpm but it's still dropping off.

I'm interested to see what power/boost other people have got with their 20g's and what spec so you are running to support it,so post them up :thumb:

Thats not a bad figure, had a RR day @ powerstation last saturday and a td0520g'd, 440's, fmic, 2.5" de-cat,apexie'd,afpr,induction kitted, andy forrest mapped 93 wrx did 327bhp, my td0520g'd 06 wrx got the highest power of the day (inc the evo's that came along) with 369.9bhp/369.1lbf.ft (has run 404.7lbf.ft on same RR with cooler temps):thumb: .