egvtec

i was told that the sc32 is too small to make 400whp and that the sc61 is too big cause it wont spool up till 5800 rpm. i have bone stock ls head with a built bottom end. what is the right turbo? i am about to order and i am gonna be running 1000 cc injectors. IM trying to make 400whp but i want something thats not gonna take forever to spool.

Makdaddynuge

sc61 w/o vtec will probably take tool long to spool. Go with the sc34, will get you to 400hp with good spool. Equivalent to a t3/t4 .63 a/r.

egvtec

where would i see full boost with that turbo?

AspectIndustries

Why not just ask this in your other thread about ($550 to spend thread)..?

But , Id say stick with the t3to4e size turbo.. sc34 etc..

Unless you like to see full boost around 5oooRPM? It really do suck with it..

DIRep972

iTrader: (1)

It'll take about 25psi or more to make 400 w/ a stock head on an sc34.. SC61 is definitly the way to go. the lag won't be bad. If you go big bore you could prolly have 20psi by 5000 and that should be enough boost to get u 400.

egvtec

yeah thats what im thinking, getting sc61 cause the other ones will take too much boost to get me there

95GSRTT

You could aslo be different and try a different precision turbo I went with the sc52 good for 600 hp instead of the 630 like the sc61, but should spool a bit quicker

egvtec

i was thinking that too but i wasnt sure how much boost it would take to get me in the 400s

DIRep972

iTrader: (1)

no offense but the sc52 uses a 60-1 compressor wheel where as the sc61 uses the gt40 56 trim compressor. One of the main selling points when the sc61 first dropped is that it was more efficient, flowed more volume and spool'd just as fast as the 60-1 wheel. This is the main reason the bandwagon started for the sc61..

95GSRTT

20-22 depending on setup Im sure, its not gonna be much different than the sc61, its got the same turbine wheel, just a 60 trim instead of a 61 trim i believe

M.A.R.C.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95GSRTT &raquo;</TD></TR><TR><TD CLASS="quote">You could aslo be different and try a different precision turbo I went with the sc52 good for 600 hp instead of the 630 like the sc61, but should spool a bit quicker </TD></TR></TABLE>

Also remember spoolup is mainly determined by turbine section... the SC52 is an SC60 (60-1) with a T350 wheel... just like the SC61. So my guess is you wouldn't be able to tell the difference in spoolup between the two turbos.

Rod Short

Need to clear up a little misinformation here.

" . . . the SC52 is an SC60 (60-1) with a T350 wheel... just like the SC61."

There are 3 different versions of the SC61. The baby one uses a T350 76 trim wheel (similar to the Turbonetics Stage V), will support up to 630 peak hp and is intended for 2.0L and under engines. The middle one (650-hp) uses a T04 69 trim while the big one (680-hp) uses a T04 76 trim, which is also known as a P-trim wheel. Spoolup would depend on which version of the SC61 you select.

" . . . as the sc61 uses the gt40 56 trim compressor . . . "

We use the compressor wheel from the GT35R, not GT40. The GT35R uses a 82mm 56 trim wheel (72% efficiency at 22 lbs) while the GT40 actually uses a 82mm 50 trim. Check out the downloadable catalog at http://www.turbobygarrett.com.

To get 400 whp at low boost levels, you need volume. When you crunch the numbers, the SC32 should give you 400-whp when it's totally max'd out, the SC34 would give 450 max'd out, the SC60 would give you 475 while the small SC61 would give approx 525. It would easily give you 400 at low boost on pump gas.

There are a number of variables are that affect spool up: exhaust A/R, wheel diameter, wheel trim, CHRA, rotating mass, etc. You're going to have to give up quick spooling to some degree to make that kind of power. If you have the bucks, you might want to consider a ball bearing CHRA to give you the best compromise between lag time and power.

Rod Short
Sales Manager
Precision Turbo

M.A.R.C.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rod Short &raquo;</TD></TR><TR><TD CLASS="quote">Need to clear up a little misinformation here.

" . . . the SC52 is an SC60 (60-1) with a T350 wheel... just like the SC61."

There are 3 different versions of the SC61. The baby one uses a T350 76 trim wheel (similar to the Turbonetics Stage V), will support up to 630 peak hp and is intended for 2.0L and under engines. The middle one (650-hp) uses a T04 69 trim while the big one (680-hp) uses a T04 76 trim, which is also known as a P-trim wheel. Spoolup would depend on which version of the SC61 you select.
</TD></TR></TABLE>

well i wouldn't consider it misinformation, just more specifity (sp?). i was assuming he was reffering to a T3/SC61.

Rod Short

The exhaust housing, whether it's a T3 or T4, doesn't affect what wheels are in the turbo. The housings are machined specifically to fit the wheels.

The term "misinformation" isn't meant as a slam, just trying to clarify what the actual facts are about our product so people don't waste $$ needlessly. You guys probably know more about this stuff than I do anyway, which is why I take the time to read this. I want to learn, too.

Rod Short
Sales Manager
Precision Turbo

M.A.R.C.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rod Short &raquo;</TD></TR><TR><TD CLASS="quote">The exhaust housing, whether it's a T3 or T4, doesn't affect what wheels are in the turbo. The housings are machined specifically to fit the wheels.

The term "misinformation" isn't meant as a slam, just trying to clarify what the actual facts are about our product so people don't waste $$ needlessly. You guys probably know more about this stuff than I do anyway, which is why I take the time to read this. I want to learn, too.

Rod Short
Sales Manager
Precision Turbo</TD></TR></TABLE>

haha nah i didn't take it that way. and i see what ur saying about the housings not making a diff. but the SC6 is sold as a T3 with the T350 wheel. I also listen to you anyway... we're Precision dealers as well.

95GSRTT

Hey Rod I was wondering if you would be able to give me a compressor map or the efficeincy range of the SC52.

Is it really that much less efficeint than the sc61? And if so do you guys have an exchange plan?

DIRep972

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rod Short &raquo;</TD></TR><TR><TD CLASS="quote">Need to clear up a little misinformation here.

" . . . as the sc61 uses the gt40 56 trim compressor . . . "

We use the compressor wheel from the GT35R, not GT40. The GT35R uses a 82mm 56 trim wheel (72% efficiency at 22 lbs) while the GT40 actually uses a 82mm 50 trim. Check out the downloadable catalog at http://www.turbobygarrett.com.

</TD></TR></TABLE>

Rod, I know the 56 trim is from the GT35R. but it is a compressor from the GT40 family. that's why the GT35R is also referred to as the GT3540R. you shoulda known what I meant

Rod Short

95GSRTT,
Actually, we do not have a compressor map for this. Garrett consider their maps to be proprietary information, which is why they have not released them to the general public. The only thing they have released are the maps from their newer GT line, which can be found on their downloadable catalog at http://www.turbobygarrett.com. We cannot risk our distributorship by releasing this information. Don't like it, but that's the cards we've been dealt.

For a long time, people thought that the Garrett GT line meant ball bearing, but it really refers to the wheel design. T-technology wheels date from the late 70's to the mid to late eighties and are more typically found on lower priced, entry level stuff everywhere. The GT wheels benefit from CFD (computational fluid dynamics)design and better manufacturing techniques with the result being greatly improved wheel aerodynamics and efficiencies. As with anything, some are better than others (depending on the application), but the GT35R compressor wheel is an exceptional design.

I'd have one on my car, but the rods are only good to 350-hp, so I don't want to kick them out.

Hope this helps.

Rod

95GSRTT

So in otherwords you would consider the sc61 a hell of alot more efficeint than the sc52? And would you assume that the spool difference between the 2 would be minimal at best?

Thanks for your input

adseguy

^^^^I would agree with that

Rod Short

Yes, the SC61 compressor wheel would be much more efficient. The SC52 would spool quicker because it's a smaller wheel, but you could make up for that somewhat with a ball bearing GT35R.

Rod Short
Sales Manager
Precision Turbo

alpha

I'm going to use a friend of mine as an example. If he chimes in that would be great. If not that's fine. His head is stock minus custom camshafts (specs unknown). He has JE 8.8:1 pistons with stock rods and ARP rod bolts. Not sure if he is using ARP head studs or not. He made 304whp and 280ft-lb a couple weeks ago with an SC61S. With an open downpipe he gets 16lbs of boost by 4,600 RPM. If he allows I will post up a dyno sheet tomorrow after the dyno of the car at 16lbs and if time allows for it 18lbs. This is on 93 ocatane pump gas with conservative timing.

adseguy

damn that's a lot of boost for only 304whp (especially on an SC61), but it is nice torque! I'd love to the dyno sheet. Whoever you are chime in

92SleepyHB

Its not laggy if you put a little bit of load on your car

alpha

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by adseguy &raquo;</TD></TR><TR><TD CLASS="quote">damn that's a lot of boost for only 304whp (especially on an SC61), but it is nice torque! I'd love to the dyno sheet. Whoever you are chime in </TD></TR></TABLE>

It may sound like allot of boost but the timing and fuel maps are very conservative as it's a pump gas / daily driven / stock rod / stock sleeve motor. Looks like we are not going to the dyno todo some more tuning. Going to be changing the head gasket tonight Had a little spike last night and the boost cut didnt work.