1980 911sc Turbo Project/Upgrade

[flat6pilot]

Hello All-

I lurk over here occasionally and find myself reading this forum more and more. I've read quite a few of the 911sc turbo conversions and have begun researching parts.

The car already has Megasquirt II EFI, Carrera manifolds and 8.5:1 compression. The motor has about 130,000 miles on it but is strong with no leaks or smoking of any kind. If I were to do a turbo upgrade I would stick to everyones advice of .4 to .5 bar.

As I looked through everyones parts lists and began looking up parts on the Internet I noticed some subtle "questionable" points.

Things like:

(Turbo) "compressor 3" inlet/2" outlet", .63 A/R
(Intercoolor) 3" inlet/outlet
(Wastegate) "46mm"
(Headers, OBX) "Wastgate 35mm/38mm"
etc...

Are there specifics to sizes I need to watch and be careful to choose so everything matches?

Here is my parts list with accompanying link if you care to comment on yes/no decision.



TURBO GT30 GT3071R Stage III Ceramic Ball Bearing $449.00 Amazon.com: CXRACING GT30 GT3071R Stage III Ceramic Ball Bearing Turbo Charger T3 0.82 AR: Automotive
WASTEGATE Tial 46mm 0.5bar Spring $560.00
HEADERS OBX $528.00 OBX Racing Stainless Steel Turbo Manifold Header 78 89 Porsche 911 930 | eBay
(I understand the argumnent with these headers and their build quality rep, so I do have my eye out for a used set of 930 headers.)
INTERCOOLER $50.00 Intercooler 11"x11 5"x3" Thick 3" Inlet Outlet Turbocharger | eBay
OIL FEED KIT TurboKraft $200.00 TurboKraft Inc : Turbocharger Oil Feed Line Set : 3K-Warner [930 CVS BWK TK] - $205.00
OIL PUMP eBay (2.5 gpm) $134.95 NEW Electric Oil Scavenge Pump for Remote Low Rear Mount Turbo Return Line 12v | eBay
TOTAL: $1,921.95

Thanks for any input.

[IMR-Merlin]

Good luck with your build. There are a lot of guys that have done them here.

I am out of the loop on this one though...

[kenikh]

My input is to do your due diligence on turbo providers. IIRC, CX Racing has a somewhat less than perfect reputation for using Chinese manufactured parts that offer great prices and not so great reliability. Look up Chinese and Garrett and you will see what I mean.

[kenikh]

I just looked at the link to the turbo you had above. Nowhere in that ad on Amazon do the words "Garrett" appear. This is assuredly one of the Chinese rip-off hand grenades that have been turning sport compact owners' motors into boat anchors. These guys use the "GT" nomenclature to fool people into thinking that they are reputable Garrett turbos. They are not. RUN AWAY.

[flat6pilot]

Thanks Kenik, I'll reinvestigate my turbo choice. I guess I was focusing too much on the configuration and not the manufacturer.

[jsveb]

Maybe Quattrorunner has got a GARRETT GT-30 for sale. Not sure, but it might fit your goal.

[quattrorunner]

Also the BW s200 series might be a good option. Not too expensive. Good strong turbo.

[IMR-Merlin]

I have some 42# injectors and a 2 bar MAP sensor for sale if you need them.

They are well seasoned, but under power for my 1.5 bar build.



$200 shipped

[jpnovak]

No reason to limit your boost to 0.4 bar with this engine running EFI. Just tune it properly.

I also question the turbo choice. Would rather see you spend a little more. I really like the Borg Warner S300SX3 turbos. The 62mm would be a good match for a street engine.

Considering a similar route myself in the future.

Save some money and get one of those sump plates with the gravity feed scavange built in. I think Harold was selling them in the classifieds. You did not budget for an IC or WMI.

[flat6pilot]

Originally Posted by jpnovak

I also question the turbo choice. Would rather see you spend a little more. I really like the Borg Warner S300SX3 turbos. The 62mm would be a good match for a street engine..

Jamie, you mean like this one? http://www.workturbochargers.com/products.html?page=shop.product_details&flypage=flypage.tpl&product_id=86&category_id=37



I still don't have the turbo choice nailed down. I don't mind spending $1400 or so. I guess I'm a little gun shy as I try to quickly learn the language.

.63 AR. I heard it was good, but not really sure what it means yet.

I'm googling the net and browsing the turbo forums to pick up what I can.

T3 or T4 housing? Umm...

I guess the ultimate learning curve would to get one and learn the hard way, but $1400 could be an expesive mistake if I get something wrong?? "No, you need this housing to fit that..." and... "the oil pick needs to be here" or, "no, your AR is wrong" etc....

If someone could nail down a few exact specs, (or an example they used on their SC) that might help flatten the curve a little. Then I'll have something to go by... It's easy to say: Get the GT30R... I look it up and it has quite a few different options.

I did pick up an intercooler. Sort of a "promise ring" to get the momentum started... otherwise I might not make the leap. I have an intercooler now... I HAVE to build a turbo now...

MERLIN: Thank you for the offer. I'll keep it in mind. I *think* I have 30# injectors if I recall. I'll have to check. I'm using the Bitz Racing EFI and using what he recommended.