Rear mounted turbo...

[Falcon Ranch]

I am finally finished with my 212 rebuild on my '61 Ranchero and am now looking into doing a rear mounted turbo system...I have two reasons for this...one being that I will not have the heat of the turbo in the engine bay and second, by using aluminum tubing for the return...it would be like having a built in inter-cooler while under boost.

I have a turbo my brother gave me that came off a Unimogg military truck that had a V8 diesel, it's brand new...so I know it's plenty big enough since it only pushed 4 cylinders.

I want to keep it simple and go with the draw through route...I am considering mounting the Holley 350 in the back of the truck and running a long throttle cable...I believe that the car will still run fine though the carb is mounted at the back...what do you think about this?

Another option is to remove the carb off the log all together and mount the turbo and carb where the battery use to be and just run my pressure tube to where the carb use to mount...this would move the carb closer to the engine...is this the better choice?

Unless pressurizing the Holley 2300 series carb is simple :roll:

Dave

 

[66Sprint6]

I ran blow thru with a nearly stock 2300 no problem. Nitrofil float and some tuning and your set. If your wantin to keep it simple, runnin a rear mount turbo is kinda the opposite not to mention a draw thru rear mount!!! Would be awesome to see, but put it in the engine bay and run blowthru...more power, less piping, simple

Check out turbomustangs.com for more blowthru carb help
Matt

 

[Army of Six]

im no professional but im thinking that a draw thru setup with the carb in the back would have horrible driving characteristics.

i would strongly recommend getting that turbo up front and run a blow thru setup. where there is a will there is a way.

if you have/want to run a draw thru be sure the turbo has the right seals in it. i remember reading that if the turbo doesnt have the right seals in a draw thru setup then the oil will be sucked into the cold side creating ALOT of smoke at WOT.

 

[Anlushac11]

Rear mounted turbo would work but I would think turbo lag would be horrible.

I saw a Camaro rear mount turbo setup for a 350 V8 supposedly because there was no room under hood. It worked but throttle response was less than ideal.

A much better solution IMHO would be to get exhaust manifold, turbo exhaust side, and downpipe thermal barrier coated to keep heat in pipe and out of engine bay.

Keeping the heat in the pipe will also keep pressure up and further improve throttle response and reduce any turbo lag.

 

[Does10s]

The main problem is that the fuel won't stay atomized for 13' worth of piping. It might work if you were under boost all the time, but when you're sitting at a stoplight the engine will probably just stall.

And that's if you can get the car to start in the first place. By the time you pump enough gas into the system to get it to start, the compressor might be "under water".
And if you do get it started and it happens to backfire.......you have 13' of tubing with fuel and air in it.

Although this is just my opinion as I haven't tried this method yet.

Later,
Will

 

[Falcon Ranch]

Thanks for the quick response guys...I believe I have built my engine right and have it prepared for the turbo...here are the mods I have done so far:

212ci with a '69 truck head and bean shaped chambers, compression 145# and flat top pistons.
Head has '78 valve sizes, new springs and guides.
1.6:1 Roller rockers and chrome-molly push rods.
260H Comp cam with .500 lift.
Clifford duel outlet header with 1800F coating.
350cfm 2300 series Holley carb, currently 4.5 PV and #55jets.
C4 with shift kit and stock 800 converter.
Stock distributor with a Pertronix ignition.

Is there a good site were I can find out what mods I need to do to pressurize my carb or maybe does10s could make some suggestions or maybe anyone here who is running the same carb...and how much to do the carb mods?

Because of the cost of my header and the cost of having it coated I would hate to eliminate that...it looks really good and does a good job of retaining the heat...I did cut the 3 bolt flanges off the header and ran both outlets to a X-pipe cut in half...the whole header now ends close to where the tail shaft is...this is one of the reasons why I wanted to mount the turbo in the back...I have watched some of the videos that RTS has and I do not see any turbo lag...even the famous two guys garage did an installation on a late 90's Camaro and they also did not experience any turbo lag...I think this is a hoaks that has arrived from the days of the first turbo charged cars that did have turbo lag ...if you can understand pressure difference between the length of exhaust and intake runs, they will still be equal.

I will still mount my turbo in the rear and have to pressurize my carb then...I will only need to run a pump to return the unpressurized oil back to the engine.

Any suggestions on a electric fuel pump?
A way to control fuel pressure with boost?
An adjustable boot controller?
Adjustable waste gate?
Adjustable blow off valve?
Distributor mods? or what dizzy works best?

Here is my set-up as of now.

And here is the turbo I want to use.

This is the exhaust side.

Sorry the pics are a bit fuzzy...my camera doesn't have a macro setting...the turbo itself I was told is a T04 in size...I'm guessing it will make a lot of boost...I hope someone here can answer my Q's as I am one of those guys that are on a slight budget and would hate to buy several key components to find what works, this is why I would want to invest into those items that can be adjusted, as they are more flexible then the fixed parts...I understand they may cost more but I look at it this way...if I invest in a blow off valve set at say 7lbs, then if later on I want to increase my pressures then I will have to invest into another blow off valve.

I am totally envious to my fellow six turbo guys...my truck really has a great throttle response that feels like a V8 and has impressed many passengers...but I am looking for that stealth under the hood stock appearance and un-cluttered engine bay and a seat of the pants power that feels like a healthy V8

 

[Falcon Ranch]

The main problem is that the fuel won't stay atomized for 13' worth of piping. It might work if you were under boost all the time, but when you're sitting at a stoplight the engine will probably just stall.

And that's if you can get the car to start in the first place. By the time you pump enough gas into the system to get it to start, the compressor might be "under water".
And if you do get it started and it happens to backfire.......you have 13' of tubing with fuel and air in it.

Although this is just my opinion as I haven't tried this method yet.

Later,
Will

I believe you are right Will...I will keep the fuel supply close to the motor then...I am really interested in keeping the hood as clean as possible...if I mount the turbo in the back and eliminate the muffler, the only mods will be an aluminum intake back to the front and it will also act as a inter-cooler and a return oil line pump is also needed...the pressure side is simple to hook up.

Is there any trick to the pressure side at the turbo?...should I have the oil intake set at any particular angle and should I have a 180 degree bend going into the turbo on the oil line to prevent the oil from draining away from the bearings?

Dave 8)

 

[66Sprint6]

As stated before, check out turbomustangs.com in the blow thru carb section or everything you would ever want to know about gettin that carb ready and then some!!!
Matt

 

[rbohm]

8) there is a company, sts turbo systems as i recall, that designs rear mount turbo systems. these systems are effective, but remember that they use much smaller turbos than they would use if the turbos were mounted under the hood. the reason for this is that it actually reduces turbo lag because the compressor and turbine wheels are small enough, and light enough to be able to spin up quickly and provide boost.

as for doing a blow through or draw through system, for a rear mounted turbo a blow through system is the only way to go. check out a book by hugh mcinnes called turbochargers. it is pubished by hp books and contains a wealth of information about setting up a turbo system.

 

[Falcon Ranch]

As stated before, check out turbomustangs.com in the blow thru carb section or everything you would ever want to know about gettin that carb ready and then some!!!
Matt

Thanks for the tip...I'll check it out.

 

[Falcon Ranch]

8) there is a company, sts turbo systems as i recall, that designs rear mount turbo systems. these systems are effective, but remember that they use much smaller turbos than they would use if the turbos were mounted under the hood. the reason for this is that it actually reduces turbo lag because the compressor and turbine wheels are small enough, and light enough to be able to spin up quickly and provide boost.

as for doing a blow through or draw through system, for a rear mounted turbo a blow through system is the only way to go. check out a book by hugh mcinnes called turbochargers. it is pubished by hp books and contains a wealth of information about setting up a turbo system.

I don't know about that...check out the video on youtube...two guys garage installed a STS system on a late 90' Camaro and that turbo looked bigger then the one I have...I do understand what you are saying about turbo lag...but until you do it yourself you don't know...as I don't know whether or not I will have lag or no lag...every system is different...I can remember people telling linc's 200 that the 1bbl carb will not work and he proved otherwise...I am happy he got it to perform well...so until I get the system finished I don't even know if it will lag or not...but at least once the system and all its components are in, swapping out the turbo for a smaller one will be a piece of cake.

Dave

 

[66Sprint6]

STS turbos arent smaller by any means. The guy who helped fab the piping for my turbo setup did one on his LT1 camaro and its HUGE...and there is very little lag either. Reason being is STS did the homework in designing the kits and turbos to work with the longer piping. Its a cool deal but I still like the traditional turbo in the bay design and look better.
Matt

 

[wallaka]

Plus they usually are designed for vehicles that have a good bit of hp/torque in the first place. This helps avoid the laggy feeling before the turbo spools.

 

[Army of Six]

plus the STS rear mounted turbos are designed for multi-port fuel injected motors.

i predict that if you try and run a rear mounted draw thru you will be pulling it all and re doing it. its just not going to be streetable.

good luck.

 

[Falcon Ranch]

plus the STS rear mounted turbos are designed for multi-port fuel injected motors.

i predict that if you try and run a rear mounted draw thru you will be pulling it all and re doing it. its just not going to be streetable.

good luck.

Just the turbo will be mounted in the back...I've decided on a blow thru system and leave the carb on the manifold.

 

[TCIC 300ci superbeast]

have you thought about mounting it just after the header? about where a cat would go.
i did one for about a week. it worked well but i didnt get all the bugs out of the oiling.
i did a blow through on that one.

 

[Falcon Ranch]

have you thought about mounting it just after the header? about where a cat would go.
i did one for about a week. it worked well but i didnt get all the bugs out of the oiling.
i did a blow through on that one.

I did think about it but not enough room for all the piping and everything else required...the rear has lots of room for the air filter and turbo and plenty of spare room which is good for air circulation...if the turbo can run cooler in the air steam, I could probably get away with a couple of pounds more on the boost.

I also did some research on all the parts I will need like BOV, WG, Adj. fuel press. regulator and a wide band and the oil return pump and I was shocked on the cost...I was thinking maybe a few hundred bucks will allow for my installation...nope, I didn't even have piping and oil line and gauges figured and I was at 2K...that's like half the price of a decent kit...I have seen turbo kits for around $3,500 for smaller 4 cylinders...but no one makes a kit for the sixes...a kit wouldn't matter anyway since I'm going way different...so I will have to save up and buy one piece at a time...maybe I can win the lottery

Maybe after I get this turbo thing eventually finished, it will encourage others to follow suit just for the simplicity of keeping the engine bay clean and the heat away...I am hoping to get into the 10's or low 11's when finished...if I melt a piston, then I will build another motor with forged pistons...but I am a long way from that dream.

Dave 8)

 

[Anlushac11]

I just assumed Falcon would be running blow through. As Will said draw through is not practical.

It was on Two Guys garage where I saw the rear turbo setup. I found a listing for a guy running one on Youtube but he has a 400+cid stroker V8.

 

[Does10s]

As Will said draw through is not practical.

A draw through systems would work fine. But the turbo and carb have to be near the engine, not in the trunk.

Also, I find this "underhood heat" thing fascinating. Turbos have been installed under the hood of cars for many, many, years without to many overheating issues. At least of what I've heard anyway.
We've been running ours for about 4-5 years now without any underhood meltdowns. Granted, Kelly's Falcon isn't a daily driver, but we do drive it on the street and we've never burned the paint off the hood!

You just need to make surey you don't have hoses, wires, or any other meltable substances away from the exhaust side of things. You know...just like normal!
Later,
Will

 

[66Sprint6]

I run my turbo under the hood, and this past summer, bout 90-95* out I forgot to turn my electric fan on leaving a cruise in, heading to another local spot to eat. I drove about 5 miles in about 20 minutes in thick stop and go traffic, gettin on it hard to make some noise (showin off a bit lol) and it didnt overheat. A good cooling system can work wonders!!! Only thing I worry bout it keeping things away from the turbo that might melt LOL.
Matt