Garrett turbo

7

72scoutII304

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I got a garret gtp38 turbo off of a powerstroke for pretty much free. I will buy a rebuild kit for it but would it be a good turbo for my 304? It's a 80mm a 1.10a/r compressor side and a .84a/r hot side. Also what would be a good carb for a turbo setup just to make alright power. I know there is serious work with this. Also the turbo is reverse rotation so idk how that would affect it. I'm not looking to run anything more then 20psi. Now I'm curious to what a stock 304 could handle in psi.
 
If yore runnin a gtp38 revers rotater turbo offin a pstroke then I wud recomend a bendix 4 chamber pressure carb offen a pw1830 engine fromma dc3 aircraft an yud need to build ye and adapter fur it tho I got sum out in teh barn out back 40. Oh I fergot psi doan go overn 25 oar therboautz.

I cee yourn froma surry co goon down ta winstin salem aitport to cee teh guyse at piedmont aviathion thell set yu up.
 
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1975ih200 said:
if yore runnin a gtp38 revers rotater turbo offin a pstroke then I wud recomend a bendix 4 chamber pressure carb offen a pw1830 engine fromma dc3 aircraft an yud need to build ye and adapter fur it tho I got sum out in teh barn out back 40. Oh I fergot psi doan go overn 25 oar therboautz.

I cee yourn froma surry co goon down ta winstin salem aitport to cee teh guyse at piedmont aviathion thell set yu up.
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I hope that wasn't a redneck imitation. If you was insisting that I'm a redneck, I'm far from it. Hondas are my main game, scouts are just my love and side hobby. I'm not a fan of the guys that ride around in their daddy's truck driving around "rolling coal" in walmart parking lot. I'm not a redneck just because I live in surry county. This was a serious post meant for a serious answers. Thanks.
 
I don't think that turbo on a 304 will work out too well.

First IH engines are low reving and tend to blow up or at least lose a valve at higher rpms.

You also have very restricted heads. You won't get much flow.

I don't have any real solutions for you just if you proceed best of luck
 
That turbo is way to much for a 304... Diesel turbos are purpose built for the conditions expected in the diesel engine environment. A gas engine is simply off the diesel chart.
I do recommend spending 3-4 hours researching this sight. You'll have to make a few assumptions on the 304. Don't make the mistake of choosing the size based on cubic inch engine displacement. Use projected under boost hp using 6-8 psi max. Works out to about 1.5 times the rated hp max..

turbochargers | turbobygarrett
 
blue smoke said:
I don't think that turbo on a 304 will work out too well.

First IH engines are low reving and tend to blow up or at least lose a valve at higher rpms.

You also have very restricted heads. You won't get much flow.

I don't have any real solutions for you just if you proceed best of luck
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I know they are low revving, I'm not planning on taking it passed the redline but I would like to put Chevy valve springs in it just incase.I was also thinking about a mild port and polish, I've been working on building a flow bench and my Dad works at a machine shop/ recovery shop so they got cars coming in all the time that if the owners sign over to pay the bill they send to the crusher so I can get a lot of practice before mine are done and I'm also thinking about a mild cam or something that will just let a little bit more air flow through.
 
Robert kenney said:
that turbo is way to much for a 304... Diesel turbos are purpose built for the conditions expected in the diesel engine environment. A gas engine is simply off the diesel chart.
I do recommend spending 3-4 hours researching this sight. You'll have to make a few assumptions on the 304. Don't make the mistake of choosing the size based on cubic inch engine displacement. Use projected under boost hp using 6-8 psi max. Works out to about 1.5 times the rated hp max..

turbochargers | turbobygarrett
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Alright thanks Robert, I was planning on no more the 9-10 psi. I know the turbo is kinda big but oh well if the all crashes and burns all invest in a smaller turbo later on. I'm just wanting to do something different, and I've searched for hours everywhere and can't find anything on a turboed 304 just the 345.
 
You posted and asked if the free turbo was ok for the 304, you got your answer and the tools to find the correct one, yet are still going to use it?

My question to you is why waste the forms time? Why ask a question and dismiss the answer?
 
I'm hardly the expert but can give you some general ideas. Get yourself a copy of hugh mcinnes' definitive book on turbocharging. Although some of the info is dated, the physics isn't. After all, gravity's been around a long time and hasn't changed all that much. 7 lbs is about 1/2 atmosphere and rule of thumb means about a 50% increase in "displacement". So your 304 becomes roughly a 450 c.I. Under full boost. Sorta. If you take the time to work through one of mcinnes' examples - he provides a step-by-step example of where the formulas come from and why - you'll soon figure out what you need and simply transfer the results to a modern turbo. If you go carb, you'll need a turbo with a seal on the compressor side.

You are right these are slow turning engines. When I calculated the flow for my 196 at around 4,000 rpm I discovered it was equal to the flow of a 164 c.I. Corvair corsa turbo I had when spinning at 5,500 rpm. The point in this is that one cannot assume the needs of an IH 304 would equate with those of a Chevy or Ford of comparable displacement. They breathe better and easily turn a whole lot faster, necessitating a turbo with larger capacity. We ain't got that going for us. Anyway, start there and see what you are getting into before slapping something on and pointlessly blowing up an engine. :frown2:
 
Mark pietz said:
I'm hardly the expert but can give you some general ideas. Get yourself a copy of hugh mcinnes' definitive book on turbocharging. Although some of the info is dated, the physics isn't. After all, gravity's been around a long time and hasn't changed all that much. 7 lbs is about 1/2 atmosphere and rule of thumb means about a 50% increase in "displacement". So your 304 becomes roughly a 450 c.I. Under full boost. Sorta. If you take the time to work through one of mcinnes' examples - he provides a step-by-step example of where the formulas come from and why - you'll soon figure out what you need and simply transfer the results to a modern turbo. If you go carb, you'll need a turbo with a seal on the compressor side.

You are right these are slow turning engines. When I calculated the flow for my 196 at around 4,000 rpm I discovered it was equal to the flow of a 164 c.I. Corvair corsa turbo I had when spinning at 5,500 rpm. The point in this is that one cannot assume the needs of an IH 304 would equate with those of a Chevy or Ford of comparable displacement. They breathe better and easily turn a whole lot faster, necessitating a turbo with larger capacity. We ain't got that going for us. Anyway, start there and see what you are getting into before slapping something on and pointlessly blowing up an engine. :frown2:
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I have a Ford f-150 with a 460, a k5 blazer with a 350 and another Chevy with a 350 I could put this turbo on anyone of them but I'm a die hard Scout fan which is the reason I want to take on this project. I know they are faster turning engines but they are just not my piece of pie. Sure it would be easier and reduce weight and bring more power to swap one of the big three engines in but where's the fun in that. I want to surprise people with my rusted out Scout II if it wasn't for the love and the multiple hours of work I put into digging it out of the weeds where my grandpa left it it to rot and all the time it took to get it to fire up run and drive I wouldn't even attempt this but thanks for the info I appreciate it and sorry for the boring story haha
 
If you want to surprise people, drive your Scout, in stock form, to a car show and park it next to some of the high dollar painted hot rods. And watch people check out the Scout instead of the hot rods. I drove my 74 Scout to car shows and did just that. Nothing special. Just your basic straight 6 with msd ignition and an air compressor for dual ARB's. I always got a kick out of more people hanging out around my Scout checking it out than the other hot rods. I'm a Ford guy, myself, but I would rather wrench on these ole IH vehicles more.
 
Another reason for wanting to turbo my Scout that I didn't state before is that I read that a turbo will help with the mpg of the vehicle which would be great even thou grandpa said he got 18 mpg out of it when he drove it
 
72scoutii304 said:
another reason for wanting to turbo my Scout that I didn't state before is that I read that a turbo will help with the mpg of the vehicle
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This is not true in the context of your post. A given engine which in this case is the IH 4 banger is not more efficient with a turbo charger.

If you want to make a given amount of power regardless of which engine, the smallest displacement engine that can run at 75% and make the desired amount of power it will be more efficient than a normally aspirated bigger engine making the same power.
 
Here is a pic of the carb I mentioned.
Since it usually operates on an engine that is internally supercharged, two speed supercharger by the way, it will work best as a draw thru design induction system.
No need for compensation for boost or building a pressure box, just bolt it on and run it!!!
It will work with water or alcohol injection and of course, an intercooler will only get you even more power.

Oh, and the metal screen will prevent your tattoo from getting sucked off your neck! Lol!
 

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1975ih200 said:
here is a pic of the carb I mentioned.
Since it usually operates on an engine that is internally supercharged, two speed supercharger by the way, it will work best as a draw thru design induction system.
No need for compensation for boost or building a pressure box, just bolt it on and run it!!!
It will work with water or alcohol injection and of course, an intercooler will only get you even more power.

Oh, and the metal screen will prevent your tattoo from getting sucked off your neck! Lol!
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I'm thinking about running a efi setup now after a lot of reading. Going back to the slow low revving what is the best way to fix it.
 
How practical is it to just go with a 'cool air intake'? Bring in the air from behind the grill and duct it up to the snorkel of the filter housing. Seal the lid to the base so the cool air stays in the filter housing and use a low restriction filter element. Might be pleasantly surprised with the result! :icon_lol:
 
bill bennett said:
how practical is it to just go with a 'cool air intake'? Bring in the air from behind the grill and duct it up to the snorkel of the filter housing. Seal the lid to the base so the cool air stays in the filter housing and use a low restriction filter element. Might be pleasantly surprised with the result! :icon_lol:
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Only problem with that for me is that my filter housing doesn't have a snorkel anymore it was long gone before it came to me and probably before I was born
 
Does anyone know the cfm of a stock 304 head? I tried searching it earlier but only found the carb info. Or is a head not measured with cfms?
 
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