How well does a hopped up IDI do?
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 16
From: Nutter Fort, WV
When you add boost to a high compression ratio engine, the effective compression ratio goes through the roof.
22.5 to 1 base compression ratio with 20 pounds of boost equals a 53.11 effective compression ratio.
Now consider a Power Stroke engine base compression ratio is 18 to 1.
So a Power Stroke running 30 PSI boost will have an effective compression ratio of 54.73 to 1.
The IDI was never designed to run boost, Ford was the only factory turbo IDI sold.
International never sold a turbo IDI engine.
So the intake gaskets and exhaust manifold gaskets need some help to keep the boost pressure where it is supposed to be.
ARP head studs keep the heads on, 220,000 pound yeild strength which is way above the factory head bolt strength.
And studs keep the intake and exhaust manifolds where they are supposed to be as well.
22.5 to 1 base compression ratio with 20 pounds of boost equals a 53.11 effective compression ratio.
Now consider a Power Stroke engine base compression ratio is 18 to 1.
So a Power Stroke running 30 PSI boost will have an effective compression ratio of 54.73 to 1.
The IDI was never designed to run boost, Ford was the only factory turbo IDI sold.
International never sold a turbo IDI engine.
So the intake gaskets and exhaust manifold gaskets need some help to keep the boost pressure where it is supposed to be.
ARP head studs keep the heads on, 220,000 pound yeild strength which is way above the factory head bolt strength.
And studs keep the intake and exhaust manifolds where they are supposed to be as well.
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
Just from knowing what I know about Dave S. from this forum if he dyno's his rig it will be for his own knowledge and not because of any pressure from some of us.
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 16
From: Nutter Fort, WV
With 40 off the pistons I used, my base compression is 20.25 to 1.
This winter I did fire it up once at 10 or 11 below when it was not plugged in, but it was not a happy camper when I did.
I may have been able to start a little colder, but everything would have to be in perfect shape.
2 1100 CCA batteries, manual glow plugs are the only reason it started.
I say this to make you aware, that cold starts are harder after you drop compression.
The farther you drop it, the harder they get.
The more attention I pay to outside air temp and the way my engine runs, the more I become aware of how much an intercooler would increase the power even more.
This winter I did fire it up once at 10 or 11 below when it was not plugged in, but it was not a happy camper when I did.
I may have been able to start a little colder, but everything would have to be in perfect shape.
2 1100 CCA batteries, manual glow plugs are the only reason it started.
I say this to make you aware, that cold starts are harder after you drop compression.
The farther you drop it, the harder they get.
The more attention I pay to outside air temp and the way my engine runs, the more I become aware of how much an intercooler would increase the power even more.
Laughing Gas
Joined: Feb 2007
Posts: 962
Likes: 89
From: upstate ny
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Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 16
From: Nutter Fort, WV
Yes I need to figure out if removing the snow plow subframe and installing an intercooler, then reversing the process in the fall is going to be worthwhile.
I would change blades, but with the lack of snow we have been having lately, I would never buy a new blade.
I would change blades, but with the lack of snow we have been having lately, I would never buy a new blade.
Senior User
Joined: Jan 2009
Posts: 112
Likes: 0
From: easton, CT
how well do you guys think a 7.3 with a hypermax turbo, intercooler and intake with turned up fuel pump new injectors and a 4in exhaust with 5in stacks... i tryed to figure out what they said typical results are i got a bout 367 horse and 675 torque think its believable?
dont mean to hijack the thread but on the general topic
dont mean to hijack the thread but on the general topic
Posting Guru
Joined: Apr 2008
Posts: 1,614
Likes: 0
how well do you guys think a 7.3 with a hypermax turbo, intercooler and intake with turned up fuel pump new injectors and a 4in exhaust with 5in stacks... i tryed to figure out what they said typical results are i got a bout 367 horse and 675 torque think its believable?
dont mean to hijack the thread but on the general topic
dont mean to hijack the thread but on the general topic
Senior User
Joined: Jan 2009
Posts: 112
Likes: 0
From: easton, CT
Cargo Master
Joined: Nov 2003
Posts: 2,585
Likes: 1
From: Duluth, Mn.
Dave. No One is saying You need a 30"X40" IC. Get a more efficient IC, and the effect will be equal, or even better than anything Ford ever strapped to a truck.
I'd bet that if You found a 10"X24"X3" HKS, Greddy, etc IC, it'd be more than capable of cooling anything You stuff down Your IDI's throat.
I'd bet that if You found a 10"X24"X3" HKS, Greddy, etc IC, it'd be more than capable of cooling anything You stuff down Your IDI's throat.
