RSMike

iTrader: (1)

what does everyone reckon about this...

ATP sells the GTX3582 for $1800USD with no exhaust housing (approx 75-76lb turbo)
http://www.atpturbo.com/mm5/merchant...Category_Code=

FP sells the HTA3582 with the exhaust housing of your choice for $1700 (approx 68-70lb turbo?, HTA 3586 is 75lb?)
http://store.forcedperformance.net/m..._Code=Turbo-FP

But in saying that, FP doesn't always have stock available and there is sometimes a large gap in production (i waited a long time to get a HTA3582 then i cancelled the order).

This will be used on a EJ25 subaru track attack car.
We wanted to use a new BW EFR 7670, but we need the car running by March.

Does anyone have info and/or recommendations?

Cheers, Mike

n2oiroc

iTrader: (33)

Hta for sure. All the testing i have seen with the gtx has shown more lag and not much more power. Hta has proven to work well.

acssa

iTrader: (2)

EFR in single scroll should be availible... its only the twins that is still out.

I know that RHD and twinscroll on a scoob is a bit tight.
I had a APS TSR70(twinscroll) kit on my sti9 and the pipe work cranked in matter of weeks.

I got a kit from Roger Clark motorsport in the UK, and that is a single scroll setup that fit RHD perfectly. More that a year now making 406WKW and not a single problem of cracks.

Now for the shock... and please dont stone me! the single scroll, with the same .82 AR housing spooled a slight bit faster.... it did dip a slight bit quicker at the top though compare to the twinscroll.

maybe the long headers on the scoobs dont benefit from twinscrolls.

SmurfZilla

iTrader: (33)

Twin versus single scroll is hotly debated here. I think AWD believes there isn not much benefit from them.

n2oiroc

iTrader: (33)

on the dyno or dragstrip i agree. for a daily driver its night and day.

spdracerut

iTrader: (2)

I would disagree. RSMike, you've already seen the other thread but Spyros went from 638whp with the regular GT35 to 741whp with the GTX35.

What is your HP target? The EJ25 doesn't really like holding together very long at the really high HP levels.... Have you considered just a regular GT3582? Another option is the Full-Race twinscroll setup with a GT4088 or 4094.

RSMike

iTrader: (1)

heya, yeah i saw Spyros results, but i'm not sure. His dyno correction is SAE, i would like to see sheets with uncorrected on it to be honest.
We recently made 680whp on a regular GT3582 with 1.06 T3 TS housing on a SR20 VVL head engine at 30psi and E85. This is uncorrected and backed up with a live dyno day at a recent event. This turbo is definitely an option, with full boost hopefully being around 4300-4600 on a 2.5litre engine and twin scroll.

Target HP is 700whp. The engine will be pulled down regularly after events to check for bearing wear on the mains and bigends, as we know this is a major weak point.
It will be used for gymkhana and track attack, so we want mega response. This is why the 7670 was chosen, and is still a valid option if we can wait till March to get it.
I realise that the 7670 will make a shade under what the 3582 can, but it will sure make for an excited ride, especially with the added response of the Ti materials. Another massive draw card in the internal wastegate, which saves a lot of weight and fabrication work.

In saying all that, i think the HTA3582 in T3 or T4 twin scroll would be really good. Single wastegate with splitter right up to the seat (for weight). If it makes more than the GT3582 and spools a little quicker, it's win-win. BUT that depends on if FP can actually deliver on this product... I know they have been slow lately with a lot of their product output. I'll be calling them tomorrow morning.

The GT40 series turbo's are out of the question because of weight, size and lack of response (size etc).

Cheers, Mike

spdracerut

iTrader: (2)

It's my understanding that the block twisting is the issue which leads to cracking. Is there some way to reinforce the block? I've spoken with Crawford at a track day before when they had their time attack STI out. They run a GT3788R that's divided on that car and also Ken Block's old gymkhana car. They can basically also crack engine blocks at will depending on how high they crank up the boost.

As far as I know, the GT35, GTX35, and HTA35 are all basically the same except for the compressor wheel. There are compressor maps for the GT and GTX so you know exactly the difference. Without actually testing back to back, the HTA is an unknown relative to the Garretts. I still think the twin-scroll Full-Race setup with a GT4094 is a viable option with regards to response and power and it's a setup you can buy as opposed to having to fabricate anything yourself. But it will be heavier.

RSMike

iTrader: (1)

We haven't seen the blocks cracking here. Maybe we haven't been pushing them enough over here to see that yet. My tuner is working with an EJ expert to get the block sorted. Closed decking and other tricks. Mains and big end bearings are more of the problem due to the block twisting under power. And they are such a small bearing (width).

The car is being built here in my tuners workshop to showcase their development and fabrication etc, so they do not want bolt on kits. Lightweight parts are a big part of the picture too.

Thats interesting that Ken Blocks car used a GT3788... Good info.

spdracerut

iTrader: (2)

Timing is pretty good..... article on GST Impreza with some engine build details just came up on MotoIQ:

http://www.motoiq.com/magazine_artic...u-impreza.aspx

Though non-Evo content, still a good read!

Ted B

iTrader: (6)

Hmmm, that setup sounds familiar ...

RSMike

iTrader: (1)

You are my inspiration Ted B
I was waiting for you to chime in!

n2oiroc

iTrader: (33)

do hta's really use borg warner compressor wheels?

RSMike

iTrader: (1)

i dont think so, they are probably trying to say they use similar extended tip designs.

So here is a list i'm trying to put together...

BW EFR 7670.. 64lb/m
GT3582........... 68lb/m
HTA3582......... 70-72lb/m ?
HTA3586......... 75lb/m
GTX3582......... 75lb/m ?
BW EFR 8374.. 79lb/m

Now we have made 680whp (510kwatw) on a very highly worked SR20 engine.
using those numbers, that shows the on the same engine the 7670 should make ~640whp.

Choices are hard to make!
The other really big part of the turbo selection is how fast that they spool...
Is there proven results that the HTA model spools faster than the GT model?
I wonder if the EFR 8374 will spool the same/faster than the HTA3586...

ScorpionT

iTrader: (1)

MotoIQ is saying its a BW compressor, but its not really from BW. MotoIQ is full of misinformation, unfortunately.

The FP designs are similar to BW compressors, but they are not the same.