I am building up a 74' Monte carlo....I really want midrange power and the engine wont spin over 5,000 RPM tops the car has a 3.08 rearend and TH350 transmission.
I am blowing thru a 575 BG Blow thru demon. This turbo is plenty big enough for my application, correct? I thought it was a bit small since it was sold as a racing unit from Full-race turbos for a 1.8 Honda...
The Honda Had problems spooling it up.
I rebuilt the Turbo with new thrust and shaft bearings and its now balanced. The intake is a .70 ar and the exhaust is a p-trim .68 ar with a clipped wheel. I know there is alot of variances that affect the turbo spooling...
I am running stock manifolds and a bone stock engine. I dont want over 10-12 PSI of boost and I really dont care if this engine lives less than a year after the car is up and running....I have a very healthy fuel system that is capable of supporting 2,000 horsepower...(I went overkill)
I am building my own alcohol injection system that works off boost....its a tank that has a pressure hose from the bonnet that pressures the tank and pushes the alcohol into the intake plumbing through a small nozzle anytime boost is enough to push it in...I learned it from a Motorcycle drag racer that holds alot of record win titles....very simple no electronics or controllers needed just various nozzle sizes to get it right or a faucet valve to control flow.

No matter what, I am using this turbo since its 85% percent done being installed...So my question is what should I expect more than do I or dont I....

The information may help me decide wether or not to mount the turbo very close to the engine or a foot or two away....Gotta love the 74' Monte for room under the hood. (I can even keep my air conditioning) Also will affect my pipe diameter since larger pipe flows more lazy....


I also welded up the stock HEI distributor to lockout the advance and I will start the car with between 18-21 degrees timing and go from there.

Any opinions that I can run with?

 

Should be perfectly fine...

 

Sweet! But to be perfectly honest I am not sure how to read that graph...I saw a bunch of different turbo's used in various applications and saw the inlet size, housing size and a few other variables that seemed consistent among applications and when this thing came up with a $300 price tag I jumped on it....I rebuilt it myself and it cost me $50 for the Garrett kit. I used the 270 degree thrust instead of the 360 degree one it had due to price and the fact I am not going over 16 pounds of boost intentionally and that was the number I was given as a cut-off point for the 270 versus 360 bearing....The shaft is .010" under stock and I bought .020" under bearings and machined them to size for a very good fit. Then Diesel injection service in Cincinnati balanced the shaft then the wheel then the assembly...so I basically have a brand new turbo now for just over $400 invested.
I bought the 38mm Tial wastegate and the 50mm Tial BOV to go along with it.
The shaft spins perfectly and the turbo has next to zero sideplay in the shaft...The only resistence was the heavy camshaft lubricant that I used from Valco products.
I am a pretty knowledgeable gear head and mechanic but the physics and paperwork of turbocharging I have not learned yet. Rebuilding the Turbo was a cake walk.
I also build exhaust systems for a hobby and got set up as a jobber at a local WH in Dayton Ohio to buy exhaust tubing and elbows etc. at jobber price. So the crossover under the pan is a also cake I have a thick piece of cold rolled steel that I am using for the T4 flange and I will weld everything up when I figure my turbo placement exactly.
My concern is the drain back tube....can I take the oil pan off while the engine is in the car? Is there a kit to puncture it and put a drain in without removal? Or should I just run a tube to the valve cover at a angle not quite as steep as I would like?

How close should the Barry Grant Blow thru Demon be out of the box....What I am asking is will it run OK or hardly at all until its tuned? or are they pretty good at being close? It has the whole gamut of goodies and costed a arm and a leg....It also has the annular boosters...Anyone have any luck with them?

 

I think I have a clue to reading that graph...the red line is RPM? So if thats right the turbo will be spectacular for my setup...Full boost all by about 3,500 RPM? Sweet...

I also polished the internals of the compressor housing to a mirror like shine....I was told this was good for about 2% efficiency. The website mentions 75lbs ??? of airflow per hour? I dont know what that means if I even translated it right....maybe it was minute...I dunno.

I am taking a bit of weight out of the car, 5mph bumper absorbers, cutting the backsides of the bumpers with the plasma cutter, took out all the tar sound deadener, lost lots of useless brackets and accessories all emissions equipment is gone etc. The car will still be large but alot lighter....should shock and amaze any passenger....I was told to that the BOV will sound pretty cool too....I have never heard one on a V8.
The Only turbo'd vehicles I have driven are a Kodiak medium duty truck with a 3408 CAT engine and a 2.0 Turbo Volkswagen GTI that was a hoot. Well I also drove a old Talon that was messed with.

So I am anxiuos to say the least to get this old boat running....I cant wait to hear the sound it makes....I rode in a buddies Grand National a few weeks ago and it was fun too....But I didnt get to drive.....Still wasnt a V8 with a Turbo...I am running a 3" V-band downpipe with Mandrel bends and no muffler at all.

 

In theory, the turbo is capable of about 750hp. 1 lb/min is just over 10hp.

 

This link may help you learn how to read these maps...


http://www.forcedinductions.com/help.htm

Jose

 

Wow thats a bunch of information..... Thanks

 

I got my car 99% put together, I just finished my fuel sending unit with 1/2" stainless lines and -8 AN fittings to drop into my tank. Just have to run some fuel lines and finish putting the accessories and belts back on the front of the motor and its ready to start.

Any Good Idea's for starting the engine for the first time and how to set up the blow through carb? what about the Aeromotive fuel regulator? I have never used one before....The screw and lock nut on top....how does that work? screw it in Clockwise to raise fuel pressure and counterclockwise to reduce? I guess with a new BG Demon I need about 6.5 Psi of fuel pressure even without the turbo...
I am setting my timing at 20 degrees and the dist. is locked out so there is no advance or retard in the system.

I planned on starting the engine and adjusting the timing and carb with the turbo not on the engine actually....especially to blow out the welding or grinding debri that could be in the crossover pipes. Then I will bolt the turbo to the flange and finish the dialing in.


Another question, Do I need to get a one-way check valve to keep the boost from hurting the transmission vac. modulator in my TH350 transmission? And what do I do about any other vacum operated items like the AC/ heater controls?

 

Quote:
I am running stock manifolds and a bone stock engine. I dont want over 10-12 PSI of boost and I really dont care if this engine lives less than a year after the car is up and running....I have a very healthy fuel system that is capable of supporting 2,000 horsepower...(I went overkill)


you know that every 14.7 psi of boost, the engine doubles it's horsepower capablities.....
so if a stardard v8 makes 350 hp, @ 14.7 psi ..( everything being right..) you should then make 700.....
cheers
ash

 

Its Alive!!!!!!!!!!!!!!!!!! It seems to run steller! I am quite rich on the AFR but until I get a wideband it will have to wait. I gotta do paint and interior then its gonna be ready to drive.

 

how is it running? where is it @ when it makes full boost? I have the same turbo and have been going back and fourth on useing it.I have a 10.5-1 motor and even tho everyone is saying it will be fine i still have doughts on it.good luck with it

 

I am making full boost around 3,000 RPM...It will start to make boost just several hundred RPM's above idle....If you foot brake it the turbo starts to whine hard quick....Cant tell a whole lot yet since I dont have a tach wired in yet and it blows the tires off it so fast that I have yet any need to rev it up more than roughly 4,000rpm. My motor is bone stock so the low compression helps me use this small A/R .68 exhaust housing.....You may want to run your turbo downstream a little bit to lower your heat efficiency to the turbo...My compression is only about 8.5.1 It makes so much boost that the wastegate opens pretty quickly. I have yet to tune it on the chassis dyno.....its running rich right now....visibly....quite a bit of black smoke when you nail it...I am also running my timing at 22 degree's locked.