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Can anyone recommend a turbocharger for an Astron II 2.6L? I am looking for around 8-15PSI and the least amount of lag possible. I currently have a Garrett AiResearch M10 that I got for free off a Pulsar ET Turbo. it has a T2 exhaust flange, A/R .47 hot side and A/R .48 cold side. I think the stock boost is 7PSI. The engine it came off was 1.5L. From what I have read, this turbo is suitable for 1.6L-2.5L engines. Other research I have done suggests I use a Garrett T25 with exhaust A/R of .60.

mate your just inpatient put a nice cam in a a decent sized turbo ,lag is just build up for what is to come.... put a gt30 or something and never look back that way if you get serious and put some internals in you dont need to upgrade turbo again...

man theres no lag with a supercharger lol

just go big turbo and high compression like about 12. so you'll have big boost with not as much lag. if your worried about head blowing just cut a ring in the head and block and put a round ring in about 3 mm thick for each piston. you'll be sweet

I was thinking about using a Toyota SC12 or SC14. I am still early into my build, so I am yet to make a final decision. If I don't end up using the M10 turbo I have at the moment, I might sell it to fund either a larger turbo or super charger.

I could be greedy and use both a SC and a large TC

i had a garrett t25 as the first turbo on my sigma. it was on full boost (13 PSI) by 2000 and ran out of flow around 3500.
then i ran a ebay t3 and that hit 18psi around 2800 and made 209kw... if your after a no lag situation maybe look at a variable vane turbo off a large diesel (around 4-5L capacity)

dont even consider putting that tiny thing on, all it will do is destroy itself as the engine is WAY too big for it.

im about 3 parts done now with fitting a eaton m90 draw threw with a 650 vac sec holley on it

Borg Warner S400 76mm with a dry shot of NOS on the trans brake no lag what so ever ;)


cheers Mic

The Garrett GT2860RS (Disco Potato) is an affordable upgrade that is suited to 2.6lt and good for up to 320Hp.
You can buy them with the option of a 0.64 exhaust housing, no lag. Only problem is they have a t25 flange.
IMHO, nothing wrong with TO4's.

The Disco Potato looks good, and 320HP is plenty. Might have to wait for that part since even my Ruddy money wouldn't pay for one. I still have to work out where I am going to get the exhaust manifold from. I might have to get one made up. What is wrong with the T25 Flange?

There's nothing wrong with the t25 flange. It just isn't a direct bolt on replacement.
You can always just buy or make an adapter.
I think ATP does a "Franky" Turbo with the mits tdo5 , they are meant to be good. I just don't know anyone that's got one but.

[quote="S1GMARE"]The Garrett GT2860RS (Disco Potato) is an affordable upgrade that is suited to 2.6lt and good for up to 320Hp.


The Garrett GT28R series is what i have been recommended for my 2.6, by a Very Very well known tuner in my area.
He uses them on S15 200s and says they are good for the 300 mark.
And no lag!

Im going for street driven, and occasional Hillclimb.
So i want instant response throughout the rev range.

If you want to check out the T04, have a read of the Thread marked question about T04s.
and you will just have to decide what you are using the car for.
If you want a hell of alot of HP.
Heaps of lag, but a rocket in a straight line.


Huge turbos arent the be all and end all.
Cheers D

hey dan you can make a big to4 like a gt 4202r to spool from 1200rpm
but it will be all out to early in the rev range
spooling the turbo is a matter of manifold design,exhuast housing,cam,and
inlet manifold
just a thought
cheers stealth

just put this 122mm turbonetics thumper on

it can support 2500hp and 140+ psi

That might just fit in the engine bay, but where would I put the engine??

amgis_obrut wrote:just put this 122mm turbonetics thumper on

it can support 2500hp and 140+ psi

Cottees wrote:That might just fit in the engine bay, but where would I put the engine??

LOL!!!!!!!!!!!!!

Disco potato gets another vote from me, i have never heard a bad word about them from anyone.

I did a heap of math using the guides and formulas on Garrett's website, and it looks like the Disco Potato would be the perfect match for the 2.6L. Now that I have decided on a turbo, I just have to try and afford it. I have plenty of other things I have to do first on my Sigma, so it isn't too much of a problem.

Helpful links :
The Disco Potato itself. As well as a flow map
http://www.turbobygarrett.com/turbobyga ... 9548_1.htm

Turbo Tech 101 :
http://www.turbobygarrett.com/turbobyga ... ch101.html

Turbo Tech 102 :
http://www.turbobygarrett.com/turbobyga ... ch102.html

Turbo Tech 103 (where I got the formulas from) :
http://www.turbobygarrett.com/turbobyga ... ch103.html

how bout sticking to a Mits turbo.... if daily drivin say a...

TD05HRA 16G 9.8T Ti-Alum wheeled turbo from an Evo7 RS (i think) literaly no lag, feels like a supercharger...

i'v been getting good results using the reverse turbo on early 4G63's and so on....

The TD05 look like a good option. It also looks to be cheaper than a disco potato. This would be good since I am on a shoe string budget. I also have some time to make a final decision since I am still in the middle of converting my Sigma to EFI.

mate i thought that the conquest's use a tdo5 16g turbo factory?
i could be wrong im sure that someone will correct me?
cheers stealth

stealth wrote:mate i thought that the conquest's use a tdo5 16g turbo factory?
i could be wrong im sure that someone will correct me?
cheers stealth

Same. I thought so too.
How much cheaper could it be than a disco potato? Especially if the tdo5 has titanium wheels n' junk.

Definately the potato.

But if your budget is an issue the standard bush bearing T03 high flowed is also good for 300HP. Only real difference is lag.

As a base to work out flow rates etc. to match my engine to a turbo charger, I went with ~8 PSI (apparently for ~160kW), 12:1 air/fuel, and of course a 2.6L engine. Numbers I got were 1.63 Pressure Ratio, 13.95 lb/min (201.88 cfm) @ 2000 rpm and 23.65 lb/min (342.25 cfm) @6000 rpm. I think the SOHC head probably will flow less than that, but it was ok for a guide. Here are the flow maps for the Disco Potato and the TD05H :

This is the maps again, with my data plotted on them:

I'm not 100% sure how to read these graphs but since a 2.6L engine uses approx 1.3L per revolution, are you sure your calculations are correct?


Cheers.

First line on the left is the surge line, when boost starts. Middle Line is max boost. and right most line is the choke line IIRC. The calculations I use were based on what was said at the Garrett website.

After seeing the quad turbo thread, I was thinking that the turbo charger I have lying around the house is one that is for an engine half the size of my engine, so wouldn't 2 work in parallel? If I could score another turbo charger cheaply, it might be interesting to try out.

cheers stealth

I would be incline to use the comp side of the Gt42 ie 76mm and a fair bit smaller exhaust wheel like a Q in a 1.00 t4 style housing more of a T51r style but exhaust wheel will be about 3-4mm smaller.


cheers Mic