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Discussion Starter · #1 ·
Yes, I searched and read and read and read. Still not sure about a few things


1969 4-53N industrial. N45 injectors, trunk pistons....ect. I am toying with the idea of a turbo. I am curious if I can blow the turbo through the air box cover on the driver's side? It goes straight in to the air box and would affectively bypass the blower. BUT, will i have a problem of the boost blowing back through the blower? I only want to boost it by about 10psi. Can I boost it higher with even larger injectors? At 10psi, I will probably use N65'sor so. I am not looking to make huge power but I do want reliable power.


You can see the air box cover right near the fuel pump lines. Auto part Vehicle Rust Engine Automotive tire
 

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If you plumb the turbo into the air box cover only you'll have several issues.
First is any boost provided by the trubo is then working aginst the blower, so more HP to turn and possibly break driveshaft.
Second, at idle it's possible the blower will overcome the turbo, loosing air box pressure and perhaps turning the turbo backwards and exhausting fresh air out the turbo inlet.

I can't see how you'd use a turbo and a blower on a vehicle engine and not have them working together, one into the other.

It has been done with a blower bypass valve fitted to the air box inlet but the turbo is still plumbed to the blower inlet.
 

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You could use a backflow valve. I use a 3" one way flapper valve on my supercharged powerstroke. You could try and use a large wastegate as a bypass. Once the boost pressure hits the set limit (spring size,) the wastegate will open up and could work as a bypass valve. At 10psi the gain will be small if any on a NA engine. I have kicked a few bypass ideas around as well.
 

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Discussion Starter · #4 ·
10psi should be a fair improvement on an N motor(?) The blower struggles to make even 1psi, correct? I want a safe level of boost/power from the N motor without worrying about draining a piston with the next oil change!! ;)

I was just spit-balling about the air box cover as it is there and easy to blow in to. I thought of using the atomotive-style BOV/bypass idea but into the cover instead of the blower endplate. The bypass on a normal Detroit set up is just that; a bypass for the turbo charge air straight to the air box. The BOV would also eliminate the supercharger air from pushing through the turbo.

The turbo boost working against the blower is very true and I have not really thought of that.
 

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Discussion Starter · #5 ·
It has been done with a blower bypass valve fitted to the air box inlet but the turbo is still plumbed to the blower inlet.
Yes, I have seen this setup. It shouldn't matter where you blower the turbo into the air box as it is still on the down stream side of the blower even on the Detroit bypass setup. Correct? I'm n ot arguing, just trying to get my head around this.
 

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There is no positive pressure in the cylinder on a NA engine. The intake ports are covered before the exhaust valves close. The turbine and greater airflow from a turbocharger help to actually build pressure. This is why a roots on a Detroit is purely a scavenging blower. Boost pressure will also depend on gearing, load, turbo sizing, fueling....
 

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Discussion Starter · #7 ·
There is no positive pressure in the cylinder on a NA engine. The intake ports are covered before the exhaust valves close. The turbine and greater airflow from a turbocharger help to actually build pressure. This is why a roots on a Detroit is purely a scavenging blower.
For sure. I was referring to overdriving the supercharge, it will struggle for 1psi. Why would 10psi do very little? I can any psi I want by adjusting the waste gate. I just figured 10 was a nice, round number.
 

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I never said it won't help. Especially if you bump up to larger injectors. More fuel needs more air. Just don't expect another 100hp. There's also quite a few differences in a turbo engine. My 54 has a 453N that was rebuilt to turbo specs with 60's has plenty of power to scoot around with. Might dig up shafers builds he plays with diffrent turbos on the Detroit's. I am sure there's untapped power with the right sizing with these days options including ball bearings, billet wheels, different housings, vgt...
 

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Discussion Starter · #9 ·
I never said it won't help. Especially if you bump up to larger injectors. More fuel needs more air. Just don't expect another 100hp. There's also quite a few differences in a turbo engine. My 54 has a 453N that was rebuilt to turbo specs with 60's has plenty of power to scoot around with.
That's why I ask. You said it would be very little if any gain. I don't want 100hp gain. But I think 40 to 50 extra is pretty easily do able or is that I much higher expectation than I will get with injectors and 10-15psi?
 

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Well hp for a 453n is usually 135-140 rated I think. The 453T is 175 and the silver 453T was 185. Keep in mind that Detroit didn't just bolt on a turbo and Walla 453T there's a list of changes from a N to T engine in the sticky above.

Very cool rig btw!
 

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Discussion Starter · #12 ·
Well hp for a 453n is usually 135-140 rated I think. The 453T is 175 and the silver 453T was 185. Keep in mind that Detroit didn't just bolt on a turbo and Walla 453T there's a list of changes from a N to T engine in the sticky above.

Very cool rig btw!
Oh no, I know that damn near everything is different from the N to the T. I thought the N was around 105hp? I have the industrial version with a swapped variable governer, for what that's worth.

We just started that engine after a 40 year hiatus. After about an hour of hooking up fuel lines and bleeding the system, it screamed to life!! It gave me a funnyfeeling in my pants! :grinpimp:
 

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For what its worth my 78' 453N with advanced timing and C50s is rated 136 @ 2800 per the information plate. You do have the 45s so you still have room to move up even without a turbo. But if you want to burn some money throw a turbo on it. I may on mine. Also if you can spare a few dollars throw it on the dyno before and after to see what can be gained.
 

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Discussion Starter · #14 ·
Good idea. I didn't think about it until you mentioned 2800. I think mine is rate 105hp at the governed 1950rpm. That would make a huge difference in hp numbers. I want to get thhis truck moving under it's own power before any turbo/injector upgrades but I figued I'd get a little head start on that. I need fix the starter or get a new one and rebuild the fuel pump next. 40 someold years of a bone dry fuel system took its toll on the pump! The injectors only took about 4 days soaking in Marvel to free up!
 

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Discussion Starter · #16 ·
Thank you! My dad bought that truck in about 1980 or 81. All the work was done in the 80's. It's not really Old's Cool tech but close. He turned it over way back in about 1992 or so. It has sit dormant since then until the other day. I'll upload a video os it, just for ****s.

This is just a idea for a bed as we have the bed. The sleep was fitted at one point but the wind picked it up and dropped it across the yard a few years back.

Land vehicle Vehicle Truck Car Transport
 

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With a sleeper it looks a lot like this one I had a few years ago.
Land vehicle Vehicle Car Commercial vehicle Transport

More pictures of it HERE
 

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Discussion Starter · #19 ·
Grigg:


Explain this set up a litte: Parts used and such. I have a hydroboost from a Pace Arrow motorhome that I plan to use on that 60. It looks very similar to the one you have shown. What slave did you use there? ANy problems with that setup? Great idea. I was looking at doing a manual linkage setup but the hydro you have shown would be great and I can mount much more out of the way!

Auto part
 

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That setup was sort of the last resort. Because of the 6V53 I couldn't fit any more master cylinder than the stock single circuit, not even the hydrobooster and 90° bracket. So I used the original MC and a slave same as they used on the clutch (from an older Dodge I think) to operate the hydrobooster and dual circuit booster.
A year or two later I saw in a magazine that Vanco made a similar setup, not sure if they have abandoned it or not.
The idea is somewhat flawed because ideally you'd have a dual circuit brake system... Which it has but still single circuit in front of it, not good for factor of safety's sake.
 
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