Sideshow Bob
Active Member
It not from Ford but it looks pretty good.
My twin turbo build
- Thread starter Sideshow Bob
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Sideshow Bob
Active Member
I'm going to try my hand at porting. If I goof it up theirs a pick a part near me that's got them for 50.00 bucks. I'm going to be under boost so on the intake side I'm just going to knife edge the two ports. Smooth out that ledge at the bowl, and a little gasket match also remove casting ridges. I shouldn't have much problem pushing air in it's getting it out is where I'm not sure about how to Port. The exhaust I read to do very little to the floor and stay mostly on the roof to keep velocity High. not sure if that little hump after the valve guide is to promote velocity or just in the way. 
Any information or do's and don't will always be greatly appreciated.
Any information or do's and don't will always be greatly appreciated.
Sideshow Bob
Active Member
Need new stock valves. Anyone know about the valve in the photo? The exhaust is stainless steel. but the intake are steel. 
fasterthanyou
Active Member
I'm not familiar with ford 3.8 valves. Mine is built ford tough with Chevy stuff lol.
Sideshow Bob
Active Member
I have 918 springs ordered. Do the LS valve require seat change? will they work with the 918?
6 Shooter
Well-Known Member
No, the LS valves do not require the valve seats to be changed. The valve heads have to be ground down a bit. Think the 2 inch head on the intake must be ground down to about 1.94" and the exhaust maybe stays at 1.50". Not absolutely certain on the sizes to make them fit and not contact each other. Then, the seats have to be hand ground slightly for a perfect fit. The dual LS springs have a higher seat number about 130 lbs, and the spring cup height has to be lowered somewhat due to their length. Those LS springs are ideal with a high lift cam. So, think it wise to find the cam first, then choose the springs based on the cam lift.
Sideshow Bob
Active Member
Thanks Phil I have supersix cam order from Tom it's 224/224 for my power goals stock valves should be ok. Someone on v6power with stock vales with porting and 130 springs was at 600hp I'm not looking for that much. I also have his pistons and connecting rods ordered. I know trying to be cheap and build HP do not go together but if I can save money in one place I have it for somewhere else. lol
Sideshow Bob
Active Member
I'm going to fill the EGR and the rod holes on the lower. I'm thinking the rod has these little plugs. Anyone try drilling them out and fill through them with JB ?
Sideshow Bob
Active Member
I was able to hone them clean with a welding rod with sandpaper tape to the end it's not a perfect 45 crosshatch but will give the J-B Weld something to bite on.
Sideshow Bob
Active Member
Well on the heads I'm going to throw in the towel. I'm shipping them to Tom at supersix. On the lower manifold I'm having pretty good luck filling up the holes with J-B Weld I'm putting the mixed up J-B Weld in a turkey spice injector syringe. And to think I used to ask my wife why do you keep all these old injector syringes a new one comes with a jar.
Sideshow Bob
Active Member
Thanks JT After trying to find someone that will do the machining for the 918 springs and adding new stock valves with guides three angle valve grind also me making a attempt at porting I told myself what the hell. I'm going to be spending all this money on pistons connecting rods cam etc. And put on a sketchy head what can I say. I had enough problems trying to find someone around me that knew what a split pin crankshaft was and how it needs to be balanced with small bob weight with 50% of mass. I was calling around Houston only to find someone in Baytown where I live that knew what to do. But this puzzle solving and knowledge gains is what keeps me going. Plus I liked what fasterthenyou said. I quote Made Ford tough with Chevy stuff. lol
Sideshow Bob
Active Member
Nice
Sideshow Bob
Active Member
In my quest to find information on a split pin crankshaft I found out that it cannot be balanced. You can only get it close. Something with vertical and horizontal axis. Ford knows this so they put a blance shaft and high vibration dampening motor mounts. This might be old news to most, but I found it interesting.
fasterthanyou
Active Member
V6 Balancing
With V6 engines, the percentage of reciprocating weight varies depending on the angle between the cylinder banks and whether the crankshaft is even-fire or odd-fire. For a typical 90-degree V6, the recommended reciprocating weight for the balancing bobweight is often 50 percent, the same as a 90-degree V8. But for some engines, like an externally balanced Buick 3800 V6, the recommended reciprocating weight is only 36.6 percent. Ford says to use 44 percent of the reciprocating weight for its odd-fire 4.0L V6, but to use 50 percent of the reciprocating weight if a 4.0L V6 has a split-pin, even-fire crank. For its 90-degree 3.8L V6, Ford recommends using 39.4 percent of the reciprocating weight for the bobweight.
The bottom line here is that the recommended reciprocating weight for the bobweight can vary depending on the application. So make sure you find out what the recommended percentage is so the bobweights will be correct for the application.
With V6 engines, the percentage of reciprocating weight varies depending on the angle between the cylinder banks and whether the crankshaft is even-fire or odd-fire. For a typical 90-degree V6, the recommended reciprocating weight for the balancing bobweight is often 50 percent, the same as a 90-degree V8. But for some engines, like an externally balanced Buick 3800 V6, the recommended reciprocating weight is only 36.6 percent. Ford says to use 44 percent of the reciprocating weight for its odd-fire 4.0L V6, but to use 50 percent of the reciprocating weight if a 4.0L V6 has a split-pin, even-fire crank. For its 90-degree 3.8L V6, Ford recommends using 39.4 percent of the reciprocating weight for the bobweight.
The bottom line here is that the recommended reciprocating weight for the bobweight can vary depending on the application. So make sure you find out what the recommended percentage is so the bobweights will be correct for the application.
fasterthanyou
Active Member
fasterthanyou
Active Member
They can be balanced. They can never be perfectly zero balanced, but they can be balanced to 2 grams or less. High end race engines spinning 10k rpm are balanced to 2 grams. 2 grams is pretty insignificant really.
Mine was balanced to 5 grams but it was done by a high end machine shop who specializes in race motors. I doubt the average machine shop will have the latest tech to spin balance split pin cranks with much accuracy.
I had the machine shop delete the balance shaft. I thought that was much pretty standard procedure that everyone did. No use in having a balance shaft when you get your crank balanced.
Mine was balanced to 5 grams but it was done by a high end machine shop who specializes in race motors. I doubt the average machine shop will have the latest tech to spin balance split pin cranks with much accuracy.
I had the machine shop delete the balance shaft. I thought that was much pretty standard procedure that everyone did. No use in having a balance shaft when you get your crank balanced.
Sideshow Bob
Active Member
Thanks fasterthenyou Yep you can only get it close. From what I can find out if you are anywhere from 40% to 50% bob weight will work. Closer to 50% on FI motors.
Sideshow Bob
Active Member
That's a good article. The balance shaft was the first thing I heaved into the dumpster. The Machinist suggested rotating the bearing to cover the oil Passage if anyone has information what size tap and plug two use and where they sourced it. I'm thinking it's not a standard tap in length. I was going to drill a hole big enough on the opposite side to get the tap down through if anyone done it this way let me know
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