Chaz888

Well still thinking about the coog with a turbo, so as luck would have it my mate is scraping his saab turbo so I now have said turbo, its in great shape and its a garett so the thing is will this turbo work ? it has AR .49 on the turbine side and AR .48 comp side with internal gate any help would be great! ho yer its going on a coog 2.5 st200.

tabetha

It's a air pump, it will work, so long as not broken of course, what bhp potential did it have on the saab ?, should be more than enough for your cougar.
tabetha

Chaz888

Not one reply ? with all the turbos on this site and not a word ? sorry apart from tabbi

Chaz888

ok tabetha the saab was about 190/200 bhp I have that at the moment I hope the turbo to push more power say 300 but dont want to kill top revs

tabetha

I would phone some saab tuners like Abbotracing, to see what the turbo will run to bhp wise, some cars have a lot of reserve as std some don't, eg the std t3 fitted to a cossie will run over 100bhp extra than std, so a bit of a lottery!!
tabetha

DrewSS

the saab turbos are low pressure turbos LPT so not sure how it would perform on the v6

Shonky

I tried a single t34 on a 3.0 v6, it barely boosted the engine as the engine was sucking more air than the turbo could give, using a VE of 90 @ 3250 rpm your engine will need 130cfm or about 8.8lbs of air, @ 6500rpm your engine will need exactly double so you need to make sure that your turbo(s) are big enough to produce way more air than the engine requires so you make positive boost, IMHO even a saab full pressure turbo wont be good enough, two would be though.

To calculate CFM:
(engine capacity in litres * engine rpm * VE * pressure ratio) / 5660

Using your engine as an example @ half the RPM you make your peak power:
((2.5 * 3250 * 90 * 1) / 5660) = 129.19 (pressure ratio is 1 for N/A)


Using your engine as an example @ half the RPM you make your peak power with 10psi of boost:
((2.5 * 3250 * 90 * 1.68) / 5660) = 217.04 (pressure ratio is 1.68 for 10 psi)

Pressure ratio = ((14.7 + boost) / 14.7)

lbs./min = (cfm / 14.7)

So at 3250rpm you need 14.77 lbs of air, at 6250rpm you need 29.53 lbs of air to make 10psi of boost into the motor

This is a compressor graph for a gt3271 with those figures in, I've used 6500 as your peak power, if that's too high then the crosses will shift left. I don't really know much about the graphs so don't really want to comment but there'll be people on here that will



This is a guide as there are so many variables but it's what Garret suggest

Chaz888

Thanks all ,just what I was starting to understand shonky its way to small will need a T3/T4 turbo ah well anyone want a Tb25 turbo ? yer also worked out too need 28.5 >31.5 lbs/min with a.63 or .82 A/R

Shonky

My t34 made about 5psi @ 3000rpm and then died off, it was supposed to be good enough to make 400hp on a 2 litre, you'd probably make a couple more psi with the t34 because you are 500cc smaller but two t3's should put you a fair bit beyond one t34, it's double the plumbing but it maybe neater than bringing all 6 pipes into 1 for the turbo then down the car as one exhaust when it's already setup for two lots of 3-1

Chaz888

two would be nice but just no room for it even with one the batt gos in the boot my basic option is to in some degree to copy the nautilus kit from the states and that comes with the T3/T4 turbo.

Shonky

For some reason I thought it was a RWD setup even though you said cougar at the top lol, FWD v6 is easier going 6-1, have you got an intercooler/chargecooler setup worked out? There looks sod all room for a decent size one

Chaz888

yer ic can go at the very front got some room there allso was thinking the turbo could go at the back of the engine in the trans tunnel lot of dead space there but would have to run a seperate sump an pump for the turbo and would have long charge pipes but its a good spot was going to ask hows your boot turbo working out?