Advanced Hemi 212cc Predator Build

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Poboy kartman

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I can see it: Chicago : Uber driver blowing into an alcohol ignition lock-out. FAIL: Uber driver to passenger: "I guess you're driving !" Passenger: :" I don't understand your language." Driver .." Just my luck...I gotta pick up a Yellow Cab driver! "
 

bob58o

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My passengers have been complaining because I have only been able to do 30sum MPH and no cell phone charger. I tell them I make up the time by blowing red lights and cutting though back yards.

That's why I needed a cam, carb, increased compression, alternator .... DUHHHH
The gas mileage is decent. (I really don't know... what is good Highway mileage for average go kart 50MPG?)
 

Poboy kartman

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My passengers have been complaining because I have only been able to do 30sum MPH and no cell phone charger. I tell them I make up the time by blowing red lights and cutting though back yards.

That's why I needed a cam, carb, increased compression, alternator .... DUHHHH
The gas mileage is decent. (I really don't know... what is good Highway mileage for average go kart 50MPG?)

Depends on how many admantium jackshafts it has and whether the whipped cream canisters are connected to the carb.....or the drivers big A$$ photo respirator.
 

bob58o

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Ok back home! LOL

UPDATE:

Head was picked up from the DynoCams PO Box Monday morning and I am waiting for a phone call from the engine builder who will cut it.

I hope he has a few hours to spare! I have lots of questions for him. I should prepare an interview cheat sheet.

Want his advice on how much to cut, thickness/material gasket, ideal compression, my choice of carb,....

---------- Post added at 06:10 PM ---------- Previous post was at 06:03 PM ----------

Also Russel at NR racing came through...
I got the Hemi valve cover gasket and the 0.027" MLS head gasket.
I told him not to worry about the jets. I ordered two 150, instead of 1, He sent me two 115 which I like better anyway.
 

chancer

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I hope he has a few hours to spare! I have lots of questions for him. I should prepare an interview cheat sheet.
Seriously not a bad idea to write down your questions. You will For sure forget to ask him something.
 

bob58o

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Well I didn't get a chance to ask any questions. The head was already cut per my first conversation with Timmy at Dyno He took off an additional 0.030" on top of the 0.005" - 0.007" that he said I had done by hand.

I was surprised and didn't have a sheet and forgot to ask about gaskets.

$20!

I have a bunch of head gaskets here now. 0.009 Steel, 0.018 MLS, 0.027 MLS, and
Slightly used 0.036 MLS. Not sure about the 0.036" I ordered before. It was only three layers? It seems like these MLS are 0.009 each layer. single layer = 0.009" 2 layers = 0.018", three layers = 0.027"..... I haven't seen 4 layers (not sure if I got the wrong gasket last time) but assuming I could stack the 3 layers of the 0.027" and the 1 of the 0.009" to make 0.036 if I need to.


I am going to test with the used 0.036" gasket and clay when I get it back.

I want to use the 0.027" gasket if the clay says I can.
 

bob58o

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So lets see if I can get an estimate of compression based off of some online calculators, charts, and Hemi head info.

I've found that milling 0.035" off a Hemi head should give about a 19cc combustion chamber.

10-15-2014 05:05 PM #32
PoPgetbizi PoPgetbizi is offline
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Okay I think I'll chime in right here. I built my Hemi with .035 milled from the head. I used a .010 steel gasket, that gave me some real nice compression.
No decking done to the cylinder block and I used a .020 over rod. My Piston came right up to the top of the Cylinder. When you figure that the stock
head gasket is about .040 if you mill the head and use an aftermarket gasket you'll run into problems. So What I did was measure for the difference
in gasket thickness. .040 - .030 for the .010 of the steel gasket. Added .035 to .030 and it gave me .065. .065 is the difference from stock, so that is the
amount of .035 from milling the head plus .030 less gasket.

10-16-2014 08:20 AM #37
sneaks12303 sneaks12303 is offline
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I believe U R underestimating his static compression....035" milled from head should give ya a 19cc hemi chamber and then poppy raised the piston .020" with a long rod and reduced head gasket thickness . I put him higher than 10/1 and no telling what his dynamic compression actually is...


http://www.csgnetwork.com/compcalc.html
9.93 : 1 w/0.045" gasket
10.28 :1 w/0.036" gasket
10.65 :1 w/0.027" gasket
11.05 :1 w/0.018" gasket
11.49 :1 w/0.009" gasket
 

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gman3850

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if possible i wouldnt mill the hemi head but weld it up

done by Brad Hill or BRADH over at karting.4cycle
 

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bob58o

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I've seen some of those. They look awesome.

---------- Post added at 02:48 PM ---------- Previous post was at 02:46 PM ----------

Got to cost more than $20 bucks! Lol

---------- Post added at 02:49 PM ---------- Previous post was at 02:48 PM ----------

The Hemi chambers are huge!
 

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bob58o

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I am a little scared because I know my measuring sucks.

P2V still worries me!!!

The thread I've been reading is basically the same.

BMJ cam
+0.020 Rod (he is flush not 0.003" below like me)
He milled 0.030" (not 0.035" like me)
He used 0.041" Gasket for meeting compression requirements for racing, but doesn't mention his P2V clearance

I ordered a 0.045" gasket to help me sleep better, but don't know what I'll end up using.
I basically have 0.009 through 0.045 to choose from (if you can do 4 x 0.009" stacked?)

---------- Post added at 05:37 PM ---------- Previous post was at 05:30 PM ----------

So excluding the 4 stacked gaskets, keeping a minimum 0.025" piston to head clearance...

I can choose...

0.027" MLS gasket (0.030" Piston to Head) = 10.65 : 1 Static Compression

or

0.045" Composite gasket (0.048" P2H) = 9.93 : 1 Static Compression

I am assuming pump fuel will work fine on either????
Premium for the 10.65?

I will have to check more carefully what P2V is this time!!!

---------- Post added at 05:44 PM ---------- Previous post was at 05:37 PM ----------

Increasing from 8.5 : 1 to 10.25ish: 1 should be about 7.5ish% increase across all RPMs if I understand the link above.
 
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