300 turbo long block build up input

sdiesel

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on the other board we have been discussing turbo build for the long block
so here goes on this board .

i have to tear down a fresh 300 engine that has never been fired, as i built it for gas but now is set with propane.

propane does not like low compression. i'm at 9.5 :1 now with hyper, dished pistons. i'm replacing with different pistons different cam and some very precise timing with a timing retarder.

Application: 1988 f350 ford dually ranch truck 4x4 with flat bed and 5 speed. heavy pulling, low rpm high rpm, towing, AG use. a torque motor
Motivation: Propane prices are half of gasoline. today 3.66 for gas . 2.56 for propane and dropping

since im rebuilding some thoughts have come to me

heat control with turbo

oil jets for the pistons

head work for the turbo.
8-9 psi boost or more if i can seal the head.

i think i will build a custom manifold from a header for the turbo

intercooler will be either from my dodge that is dead, or i will build a heat exchanger with glycol( smaller , more efficient) remote tank with its own fan.

this is begining to sound like fun

any ideas that will help me along?
 
Doesn't look like there are any takers on this thread.
How is the project coming along?
Do you still need ideas?
 
yeah man, i dunno how i missed this, but its a cool topic. definitely worth some bench racing.

i did a R+D project with some engineers a couple years back that worked on huge 4 stroke piston engines powered by natural gas, they were running nearly 35% efficient on some of their engines.

the key is super low rpm (600-1800 rpm), super high pressure turbos (3-5 bar absolute)... massive intercooling (intake air temps 130-150F) ... lean mixtures and very very precise control of timing with a super high power spark to ignite marginal mixtures. They could go well over 20:1 on natural gas and still get it to burn.

the constant rpm thing is going to be really tough with a truck motor, but the right cam with the turbo can certainly keep it down

the turbo thing is easy. my build is using a small-ish turbo, but there are so many good ones out there its pretty easy to pick something to deliver enough pressure. if you can keep your revs low, one of the smaller hx holset turbos might be a good choice with the high pressure ratio.

the intercooler, sounds like a big dodge is one of the biggest and most efficient you can get from the junkyard.

the spark is going to be the toughest part because conventional aftermarket ignitions don't give enough control to keep you safe under those conditions. I think this would really be the missing puzzle piece for someone putting this together in their backyard. Some sort of microcontroller (ardunio maybe) that can be outfitted with sensors and run a table to manage spark over varying operating conditions.

the other challenge, those guys had unlimited access to data acqusition and testing. The difference between seizing a piston or not at those kind of temperatures (EGT's over 2000F... turbos glowing red hot) is measured in 10,000'ths of an inch. Often times the only way to tell is to actually seize a couple pistons.
 
i started this thread ; guess i should reply
ive been out pipelinin' on the desert this summer and my attendance here has been sketchy

i have not done anything to this rig in the summer but am refocused largely because i need it this winter
i found a Ford Slide-in camper and its too tempting to put that camper on the ranch truck and follow the work through the winter. its going to be a cool combination except every rig i own looks like its been through .... well, they do go through hell when i use them.
if i could get ahead of the body work a ford dually 4x with a ford camper would really be the ticket.I would be impressed anyway.
doubt others would even notice not that that matters.

my plans have not changed i am still looking for a HD exhaust manifold for the turbo. I am going to make the EDS ignition system work on the inline, and eventually i would like a Gas REsearch throttle body instead of the IMPCO 425 i have now.

getting there is not so much money as it is accurate use of time.
during work in the Oregon Desert, i drive by these ranch yards scattered among the thousands of miles of nothing and i see many odd and interesting things; i make note of the locations and plan to return to ask the folks if they might by chance have some of the dead rigs with a 300 six in them, and maybe a manifold i could buy....who knows what else i might find

when i get the whole thing sticthed together with the turbo, we tear it down and put forged pistons in and whatever else i learn that i have to do to make the block tough enough for a turbo.
If i control intake temp, and increase oil cooling through oil jets on the pistons, i might be able to overloook the fact that i overbored the block .60 thousands and that may be too thin a wall for the turbo pressure and the generated heat.

i am looking for heat exchangers that i can build or buy that would do a better job o' cooling than air to-air.

i still plan on a rear mounted radiator so i can use the front area for more space to build up the cooling when the heat exchanger idea gets too complicated.
complicated like this:
suppose i use a rear radiator for the engine block with dedicated fans and electric water pump.
use the front mounted radiator to cool the coolant i use to supply the seperate heat exchangers for the intake air and the oil cooling i can go big on air cooled radiators and much smaller on heat exchangers but overall increase my cooling effect by splitting out the cooling responsibilities.
 
The electric water pump and electric fan is a good plan.
We just went through a similar situation with a large street engine that had cooling problems at low rpm low speed cruising.
The standard belt driven water pump was not moving enough water volume at low rpm.
The electric fan moves plenty of air when the car is moving slowly.

If the intercooler is going to be in the front, why go from air to liquid to air when you can just go air to air?
I can see it if the intercooler radiator is in the back but not in the front where the air hoses and tubes will be short.
A large front mounted air to air intercooler radiator with an electric fan will move plenty of heat.

The only time we used a liquid intercooler was for racing where ice water was replaced every round.
We could get the intake manifold air temps below ambient at 25 lbs of boost.

I would not use a .060" over block for a forced air engine build.
Try to find a low mileage block that only needs a minor bore and hone to clean up the cylinders.
When you find a block it is a good idea to sonic check the cylinder walls for core shift.
Since you will be using custom pistons the bore can be just a little over 4.00"

Consider using off the shelf BBC 5.385" rods for the 2.100" rod journal. Eagle CRS6385B3D is one example
By the time you buy a set of "No oiling hole" rod cores (Unless you already have a set) polish, shot peen and resize with ARP bolts the aftermarket BBC rods do not cost much more.
The BE width is the same as the 300 Ford and the longer rods will let you use a shorter piston skirt.
As it stands the bottom of the stock 300 piston skirt travels 1.100" below the cylinder at BDC getting in the way of any oil squirters you try to install.
 
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