[64Swede]

Hi. My first post here. I have a 64 Lemans that i would like to turbocharge. It has a barely stock 350 from a 68 Firebird (YJ code) with #17 heads and a TH 400. I will probably use reversed stock logs and a Schwitzer turbo from a 12 litre diesel truck. The turbo has 67mm inducer and a 1.25 a/r ratio on the exhaust housing. Boost would be about 7-8 psi now, higher later when i have forged pistons and rods etc. First i thought i´ll go with a Holley blow thru set up, but since i also would switch to E85 i think its better to go with an EFI system. A blow thru E85 carb would be pretty expensive, and i have a Haltech F9 ECU already. The engine has 9:1 cr now and i would like to keep it there. Gas prices in Sweden are ridiculous high, about $8,34 per gallon for the cheapest pump gas (not kidding, E85 is a bit cheaper). So loosing MPG is not an option. I will use the car for some roadtrips and some action at the strip. The question now is if i should keep on using the Summit 2802 thats in the engine now or switch to a new Comp Cams DEH255 that i have. (255/261 adv 202/212@.050 0.450/0.462 110lsa 1000-5000rpm). The engine turns about 2.000 rpm at highway cruising with 3.08 gears. What do you guys think about this set up?

[Craig Hendrickson]

Do you have a turbo map for the Schwitzer turbo? I'm concerned about it being too big for the 350.

The CC DEH255 would be a far better choice than the K2802.

EFI is much easier to DIY than a blow thru due to fewer leak points and an O2 sensor as part of the system.

[64Swede]

No, i dont have a compressor map for it. I´ve been searching for what specific turbo it is, but the tag is lost. All i know is that its from a 12 litre Scania diesel truck. I thought i´ll keep the engine as stock as possible and add that turbo too see whats happening since i already have it. Used truck turbos or china stuff are pretty cheap, so i may change my mind depending if i find anything for sale at the right price. The best would probably be two smaller turbos, but i cant spend too much on this project right now. Unfortunately the EFI doesnt use O2 sensor, but i have a lambda meter so i may be able to tune it pretty good anyway i hope.

[RUDOLFSSON]

Can you post detailed pics of this turbo?

[64Swede]

[BruceWilkie]

http://www.pontiaczone.com/forum/att...9&d=1202014998

On page 85 and 86 they list the Scania diesels. IIRC the pdf is the Garret equivalent. Maybe this will help.

[64Swede]

Great link! But according to it, Scania has not used Schwitzer turbos, so i maybe wrong about that.

[64Swede]

Or, how would a pair of these do in my application? http://cgi.ebay.com/ebaymotors/T3T4-...Q5fAccessories

[Craig Hendrickson]

A pair of turbos is probably 4 times harder to install than a single. Something the size of a single AirResearch TO4B would do nicely in your application.

[64Swede]

Interesting calculators on your site! I dont mind the work. I´ve been dragracing a completely homebuildt 67 Volvo with a four cylinder turbocharged Volvo engine, so i know what it takes to build intake and exhaust manifolds etc. Best ET was 11.33/131 @ 20 psi of boost, and i won the championship in the "Euro Stock" class one year. But it was ten years a go so i have lost some of the track in turbo sizing. I dont have very much money to buy fancy stuff for, and used Holset HX units are pretty cheap here so i maybe look at one of those. A HX50-55 maybe. But twins would make a more clean setup, and since i dont have any inner fenders there is plenty of room.

[BruceWilkie]

a pair of Hx 35's would be about right. (Cummins 5.9 diesel) Diesel runs near half the rpm range. The turbine should be pretty close too. Its fairly tight so the diesel can spool early and quick before redline. Each could move up to about 45 lbs min at 2.0 PR before they start getting choked. Yet still be to right of surge line (@9 lbs min each at 1.12 PR). (2500 rpm or there abouts is where a pair of these will start making boost on a 354" engine)

A single BW s472 would work very well and can be bought new well under $700.00. It wont have the max hp potential of a pair of hx35's but certainly enough for 750 hp. S475 might be on the edge of or into surge at lower boost levels at that CI.

BTW I dont like either cam. 2802 is too big and likely to affect spool negatively on a 354. IMO the little Comp cam will have too much cylinder pressure. Remember you have iron heads and close to 9:1 actual compression. With stock logs and fairly tight turbine I'd rather see a single pattern similar to the old Comp HE 268(218@.050) but ground on 115LSA installed 4-6 degrees advanced.(109-111 ICL) . Head flow balance and back pressure are why.

[64Swede]

Best available pump gas is about 95 octane, or E85 wich i would prefer. I think I'll try the comp since im curious how it will work. This car has always been over cammed.. Im not familar to the BW units, are they sold under a differant name in Europé? If i would go with a single, wich HX unit would be about right?

[Overkillphil]

Howabout reversing a set of Hedman shorty's instead of logs? Has to be better(?)!

[BruceWilkie]

Originally Posted by Overkillphil

Howabout reversing a set of Hedman shorty's instead of logs? Has to be better(?)!

Not really. Mild steel is very prone to cracking in turbo applications. Logs will support big power probably up to 1000(possibly more) if the right cam timing is used. Wont hurt to port them a bit though. http://forums.maxperformanceinc.com/...d.php?t=671525

Again the comp cam and the summit are NOT good choices for his application. Single pattern or possibly slight reverse split with little overlap anywhere. A bit of underlap wouldnt hurt it. 112-115 LSA depending on durations. No bigger than 220 @ .050 with a hydraulic flat tappet.

A pair of HX or HY 35's from a Cummins 5.9 diesel will match very well. Plenty of Holset info here... http://www.dsmtuners.com/forums/turb...-part-5-a.html

Actually the whole thread is worth the long read. http://www.dsmtuners.com/forums/turb...et-turbos.html

BTW here is the link to Borg Warner. http://www.turbodriven.com/en/perfor...s/default.aspx See if there is a dealer near you. The S400 turbos can be had here new in box for around $650.00(USD) A single S400 w72mm inducer or S400 w75mm inducer will work quite well for you. Std 96mm turbine wheel with 1.10 or 1.32 AR depending how early you want boost.

[Bluethunder1975]

I was looking at doing the turbo on my P350..

You say your going to flip the manifolds, will this work? When I looked on my 350, the bolt holes don't line up when manifolds are flipped.

[taff2]

No they won't flip so that the outlets are pointing up,but you can swap them from side to side to have the outlets point towards the front of the car,then use a J pipe to the turbine inlet.