Never Done, Build Thread for Kenne Bell Supercharged 5.0 Explorer with Ranger Edge Front Clip

[410Fortune]

copy that!! we do what we can

 

[Blown]

I am working too much to work on my rig, but the bonus on all that work will pay to refurbish the short block.

I am now thinking Keith Blacks hypereutectic pistons. I think it would be peace of mind at 9lbs. Necessary or not?

I may drop compression a bit. I read something about better performance but need to research it again when I am not on the computer 10+ hours a day for work............... Any thoughts?


If I go that direction, I know to do the F150 T-case swap or I'll wreck the t-case and/or front axle.

 

[vroomzoomboom]

Why hypereutectic and not forged? That kind of a step down

 

[CDW6212R]

Factory pistons are hypereutectic, they are good for very mild boost. Tuned well they can handle 9psi, but forged pistons are best if the goal is boosted power.

The 9.0:1 stock compression is good for boost, but if you know the boost will be mild, then it might be helpful to run it up more. Tuned right, you can use 9.5:1 or more, which will gain more bottom end power given the boost level. Plus it's possible to go easier on the boost, while staying at the similar power level, and gain a little fuel efficiency.

We always want as much compression as the fuel and usage can handle.

 

[Blown]

Pasting a couple general rules fro here: Xcceleration

"A higher compression engine with low induction pressure will perform much better 'off boost' because it still has its own natural compression to generate power; it will generally not have a big jump in power, and as the induction device is generally smaller, its boost threshold will be much lower.

A low compression, big boost engine will make an insane amount of top end power, but be very wheezy and powerless down low, whereas the same sized engine with higher compression and lower boost will be very torquey low down, but won't make as much top end power."

And:
"you always pick up more power by adding boost and lowering compression, because power potential is based primarily on your ability to burn fuel, and that is directly proportional to the amount of oxygen that you have in the cylinder. Raising compression doesn't change the amount of oxygen/fuel in the cylinder; it just squeezes it a bit more."

I am after daily drivability and a little fun off the line, not the high rpm direction, and a roots without an intercooler makes too much heat at higher boost levels. If the stock piston are Hyper then I may just get a stock rebuild............I am going to run their calc and see how much change a lower CR will make.

sqrt((boost+14.7)/14.7) * CR = ECR

sqrt = square root

boost = psi of boost

CR = static compression ratio of the motor

ECR = effective compression ratio

 

[boominXplorer]

I run 10 lbs on my 4.6 mustang with stock internals (9.5 CR). I decided that if I go to forged internals I will aim for around 9.0 CR. My KB blower will max out around 17psi depending on setup and it does not warrant going down to 8.0 CR (factory cobra 4.6). The limits on the 4.6 are the rods at 450-500 hp. I'm at 380 whp now so any more and I'll be chancing a rod toss.

Strength of parts being used needs to be considered just as much as CR. I think you'll be fine all the way to 6lbs on bone stock 302. I'd say any more than 9lbs you may want to look into different internals but up to there throw some good head gaskets on and let it rip. I'd save the internal money for later.

 

[Blown]

A general rule is that anything over 12:1 ECR on pump gas is going to knock. So that is a good target or short of it with other concerns.

Stock
9lbs Boost 9.1CR = 11.55 ECR is Safe with a little margin for error on pump gas and I wont go any higher on boost for heat concerns with this blower.

10lbs 9.1 CR = 11.79 ECR does not leave much margin for high temps or bad gas.


0.5lb lower CR = 8.6:1
12lb Boost 8.6:1 CR = 11.59 ECR Safe on pump gas and 1lb boost 3.4% more, 4lbs X 3.4 = 13.6% more minus 1.5% for loss of 1/2lb CR = 12.1% more power gained!!! So 1/2lb decrease in CR allows the blower to pump up to 13.6% more oxygen into the engine without knocking at 12lbs of boost.

I will stay with stock compression for what I am doing and the blower I am running without intercooling.

 

[Blown]

I have additional margin for error as the altitude here plays a part. My concern has been driving out of the hills when I was running maximum boost in the past and knocking.

Correct Compression Ratio = FCR minus [(altitude/1000) x 0.2]

CCR = 11.55 - [(5280/1000) X 0.2]
CCR - 11.55 - 1.06 = 10.49

 

[vroomzoomboom]

my 2 cents
spend the money on good forged pistons, and dont skimp on rings. this way later if you decide to go nuts later on. good example i would say 15 years back i built a 429 big block from a 68 bird to put in my 81 capri. i probably spent 1500 back then on the rings and pistons alone. forward 4 years ago, i had to sell it all and never did get to finish everything. the guy that bought it stuck it all in a 90 mustang then hucked a 300 shot at it. it held without blinking, and when i built it, it never crossed my mind for nitrus.
now my old motor, i had a m90 ee kit on it with stock everything inside. i had it to 9 psi but cant remember if it pinged or not. then with the m112, cant remember either because it was only on there for about 2 months before the 347 went in
now with the stroker, the motor is 10.2 to 1 and i think i am around 7 psi of boost. on a really hot day i can hear it ping slightly under 2000 rpm with light throttle. on it, full on it i have no idea. its too damn loud.
the m122 that i am making is going to but innercooled (unlike the last two) and i have no idea what it will make with boost and a coller.

 

[Blown]

[QUOTE="boominXplorer, post: 3807142, member: 12558"
Strength of parts being used needs to be considered just as much as CR. I think you'll be fine all the way to 6lbs on bone stock 302. I'd say any more than 9lbs you may want to look into different internals but up to there throw some good head gaskets on and let it rip. I'd save the internal money for later.[/QUOTE]

Yup, feel better about it now having comments and running the math.......

I would like to, but it is no likely that I would set-up an intercooler and run more boost. Then I would want forged internals, better heads, exhaust and all. There is a limit in what I should do and how long I will have this X.

Thanks Gents! Now back to work for me.

 

[Blown]

my 2 cents
if you decide to go nuts later on.

Ha ha, good stuff, really, I have gone nuts in the past with this stuff, don't encourage me. I need to keep this more on the moderate side. I hope I don't regret the decision on the short block. I got to look at the price difference to make a final decision.

I did bust a piston, the ring land, at moderate rpm and towing a guy out of the sand, years ago, under boost, stock 302 but with a poor tune....................................................FMU rather than a good electronic tune.

Thanks!

 

[Blown]

I found an old Desktop Dyno Run for an Explorer 5.0 on 9lbs of boost. This is a pretty realistic graph with stock cam input, supercharger, and headers. 240ftlbs at 2,000rpm

 

[Blown]

Yep,

Merry Christmas and Happy Holidays!

I'll get in to my engine builder next week to get a price with forged pistons and good rings set-up for boost. I want the added safety and may add more boost down the road. It's not much more in cost for the added benefits.

Ran numbers again.
Looks like I got a 5lb pulley and an 8lb pulley (adjusted for this altitude). That's 6 and 9.5lbs at sea level. I am going to want another pulley for out of state driving.

 

[Blown]

Geeking on numbers for boost and football. Pulleys diameters with new air pressure correction for 5.500 feet. I am using 12psi for 5,500'. In the sea level equation below it's 14.7psi.
((14.7+Boost) / 14.7) x (engine liters / 2)) / Supercharger Size liters = Theoretical Pulley Ratio*


4” or 4.000 pulley = 1.56:1 = 6lbs of boost, 4.5lbs at 5,500’

3 ¾” or 3.75 pulley = 1.67:1 = 7lbs boost, 5.8lbs at 5,500’

3 5/8" or 3.625 pulley = 1.72:1 = 8lbs boost, 6.4lbs at 5,500’

3 3/8” or 3.375 pulley = 1.85:1 = 9lbs boost, 8lbs at 5,500’

2 3/4” or 2.75 pulley = 2.27:1 = 14.5lbs boost, 12lbs at 5,500’

I am running numbers cause I got no actual boost. I will calibrate with the actual boost pressure with the 4" pulley, then add to get 6lbs at this altitude. I got 145,000 mile running gear, hope she holds!!!!

 

[CDW6212R]

Geeking on numbers for boost and football. Pulleys diameters with new air pressure correction for 5.500 feet. I am using 12psi for 5,500'. In the sea level equation below it's 14.7psi.
((14.7+Boost) / 14.7) x (engine liters / 2)) / Supercharger Size liters = Theoretical Pulley Ratio*


4” or 4.000 pulley = 1.56:1 = 6lbs of boost, 4.5lbs at 5,500’

3 ¾” or 3.75 pulley = 1.67:1 = 7lbs boost, 5.8lbs at 5,500’

3 5/8" or 3.625 pulley = 1.72:1 = 8lbs boost, 6.4lbs at 5,500’

3 3/8” or 3.375 pulley = 1.85:1 = 9lbs boost, 8lbs at 5,500’

2 3/4” or 2.75 pulley = 2.27:1 = 14.5lbs boost, 12lbs at 5,500’

I am running numbers cause I got no actual boost. I will calibrate with the actual boost pressure with the 4" pulley, then add to get 6lbs at this altitude. I got 145,000 mile running gear, hope she holds!!!!

You should be fine if everything is mechanically sound, trans shifts solidly in all gears, nice fluid in everything etc.

I have 228k miles on my Black Coal project truck, and it lost 3rd and 4th gears about four months ago. I'll get a new 4R built soon, and do the timing chain set when I can. But the blower project will go onto this high mileage engine, it should be fine with mild boost. I too will aim for a big blower pulley, and try to keep the boost to about 10psi or less. I'm thinking a 3" or slightly larger should be the place to start. My final crank pulley will be 7", that's set already.

 

[Blown]

Inspected engine cylinders and they look good, will hone myself and rebuild with some forged pistons and good rings. I picked-up an engine hoist and stand. Got a raise and still have more work than I can get done...............

Played with getting the cool air intake isolated behind the passenger headlight and installed bezels in fenders.

I got some tint spray to try on the bezels to tone them down to dark chrome.

 

[donalds]

keep it up

 

[Blown]

49ers kicked butt, game got boring so I painted.

 

[Blown]

I started honing it and could see some deeper wear spots at the bottom and top of the stroke.

I took the block in, They machine it and I will build it. My engine builder is suggesting machining the rods to accept stronger ARP rod bolts. That will equal the strength of forged pistons and high quality rings. I should know Friday if it needs to be bored.

It will be built for more boost if I want to add more down the road and it won't pop a piston!

 

[Blown]

I should have the block back next week. The rotating assembly is being balanced. I got some more clean-up and prep to do this coming weekend and I hope to build it the following weekend, Leap Day and March 1st!