406 rotating assembly questions...
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by MotorHead
Alot of this stuff is overkill for street/strip motors in my opinion. The same goes for forged stuff like cranks, not really necessary unless it is a dedicated race car. A good cast crank will hold up for many 1/4 miles passes in the 10 -13 sec. range. 
RACE ON!!!
Thread Starter
Instructor
Joined: Jul 2004
Posts: 245
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Thanks for all the information...I really appreciate it.
If my machinist can give me a good price for all the machine work and balance the internals I will probably buy the individual parts and go for it. If not, I plan on calling SDPC and see if they will put together a package that has the proper parts for my needs at a good price including balancing.
I have thought about some aluminum heads, but these Sportsman II's seem to work really well. If I had stock heads then I would go for the aluminum heads.
Thanks,
Jeff
If my machinist can give me a good price for all the machine work and balance the internals I will probably buy the individual parts and go for it. If not, I plan on calling SDPC and see if they will put together a package that has the proper parts for my needs at a good price including balancing.
I have thought about some aluminum heads, but these Sportsman II's seem to work really well. If I had stock heads then I would go for the aluminum heads.
Thanks,
Jeff
Thread Starter
Instructor
Joined: Jul 2004
Posts: 245
Likes: 0
I just thought of a question about the 400 4 bolt block...
What area of the block is weaker than the 2 bolt? Is it something that could be "fixed" by a partial fill of the block?
Just taking a shot in the dark.
Thanks,
Jeff
What area of the block is weaker than the 2 bolt? Is it something that could be "fixed" by a partial fill of the block?
Just taking a shot in the dark.
Thanks,
Jeff
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
No. It is the bulkheads, at the bottom of the cylinders and the main bearing webbing. It's ironic. Exactly the area that the 4 bolts for the caps thread into, is the place where the block is the weakest. There is nothing wrong with the caps or the bolts.
RACE ON!!!
RACE ON!!!
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
After reading through all your posts, I think I'll forget about the crank kit price I got today. Anyone know the link or address from a place called Powerhouse, I believe? They had pretty good deals on rebuilt 5.7's w/good bolts, cranks, etc. I can't find them. P.A.W. is around the corner from me, but....Nah, I won't 
Thread Starter
Instructor
Joined: Jul 2004
Posts: 245
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After talking with different machine shops, as well as those of you on this board I have decided what path to take.
I am going to keep my stock crankshaft, order new Scat Forged Rods and a set of Speed Pro pistons.
I have a question on the Scat rods...is it worth the extra money to go with the 7/16" cap screw I beam rods (250.00) with all the bells and whistles, or go with the 3/8" wave lock standard I beams?
Final question...for today anyway...would you go with the Hyper' pistons ($180.00) or with the Speed Pro LW2606F30 forged pistons that cost (380.00) and have the same weight as the Hyper's?
Both pistons would be within .3 compression points from each other.
The forged would put me at 9.96:1, the hyper's at 10.27:1.
Thanks,
Jeff
I am going to keep my stock crankshaft, order new Scat Forged Rods and a set of Speed Pro pistons.
I have a question on the Scat rods...is it worth the extra money to go with the 7/16" cap screw I beam rods (250.00) with all the bells and whistles, or go with the 3/8" wave lock standard I beams?
Final question...for today anyway...would you go with the Hyper' pistons ($180.00) or with the Speed Pro LW2606F30 forged pistons that cost (380.00) and have the same weight as the Hyper's?
Both pistons would be within .3 compression points from each other.
The forged would put me at 9.96:1, the hyper's at 10.27:1.
Thanks,
Jeff
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by 406shark
I have a question on the Scat rods...is it worth the extra money to go with the 7/16" cap screw I beam rods (250.00) with all the bells and whistles, or go with the 3/8" wave lock standard I beams?
Final question...for today anyway...would you go with the Hyper' pistons ($180.00) or with the Speed Pro LW2606F30 forged pistons that cost (380.00) and have the same weight as the Hyper's?
Both pistons would be within .3 compression points from each other.
The forged would put me at 9.96:1, the hyper's at 10.27:1.
Thanks,
Jeff
Final question...for today anyway...would you go with the Hyper' pistons ($180.00) or with the Speed Pro LW2606F30 forged pistons that cost (380.00) and have the same weight as the Hyper's?
Both pistons would be within .3 compression points from each other.
The forged would put me at 9.96:1, the hyper's at 10.27:1.
Thanks,
Jeff
There is a similar, "toss up" over the pistons. I think *I* would go for the hypers, for the little extra compression and the savings, in this budget motor. If you think you may want to spray, some day, go for the forged.
RACE ON!!!
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Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
Huh, I must have missed this thread.
I have the Scat 9000 crank in a '509' 2 bolt block with main studs, Scat 6.0" H-beam rods and SRP forged pistons.
To correct Motorhead (
) I shift at ~7300rpm at the strip and I have had no problems thus far.... That said, I am going to tone it down and set my limiter at 6800 from now on. The short block has 12,000 very hard miles on it and I want it to last until this fall when I plan to tear it down and freshen it up.
I am curious to see how the bearings, rods, bores, pistons, well everything look.
As far as cost it wasn't THAT much more to go with the H-beam rods and good forged pistons.
The rods were $400 and the Pistons were $480... Ok so maybe it was a little more....
I have the Scat 9000 crank in a '509' 2 bolt block with main studs, Scat 6.0" H-beam rods and SRP forged pistons.
To correct Motorhead (
) I shift at ~7300rpm at the strip and I have had no problems thus far.... That said, I am going to tone it down and set my limiter at 6800 from now on. The short block has 12,000 very hard miles on it and I want it to last until this fall when I plan to tear it down and freshen it up.I am curious to see how the bearings, rods, bores, pistons, well everything look.
As far as cost it wasn't THAT much more to go with the H-beam rods and good forged pistons.
The rods were $400 and the Pistons were $480... Ok so maybe it was a little more....
Thread Starter
Instructor
Joined: Jul 2004
Posts: 245
Likes: 0
I too changed my mind on my engine.
I decided why not? I went with the Scat 9000 crank, 7/16" cap screw I-beam rods, Speed-Pro Hyper pistons. After decking the block and cleaning up the surface of the heads I ended up with 10.44:1 compression.
Runs excellent...haven't had it to the track yet, but it feels strong.
Later,
Jeff
I decided why not? I went with the Scat 9000 crank, 7/16" cap screw I-beam rods, Speed-Pro Hyper pistons. After decking the block and cleaning up the surface of the heads I ended up with 10.44:1 compression.
Runs excellent...haven't had it to the track yet, but it feels strong.
Later,
Jeff
Thread Starter
Instructor
Joined: Jul 2004
Posts: 245
Likes: 0
Originally Posted by VETDRMS
How well does that compression work with the iron heads? Have you checked your cranking compression?
Did you change cams?
Good Luck at the track! What tire/gear do you run?
Did you change cams?
Good Luck at the track! What tire/gear do you run?
So far the compression is working good with 92 octane and 34 degrees total. The engine only has about 250 miles on it at this time so I'm being conservative with timing and throttle at this time. I have not checked my cranking compression yet. I plan on it in the near future.
I ended up installing a new cam and lifters...but I used the same part number/grind from Crane that was in it. When I inspected the cam and lifters number 1 exhaust had a spot on both the lifter face and the cam lobe that made me uncomfortable about reinstalling it.
At the track, and sometimes on the street I run BFG Drag Radials mounted on a spare set of matching ralley wheels, they are 275-60-15's. I usually run them down to about 14 pounds of pressure on the track...and 28-30 on the street. I have a set of Richmond 3.70 gears in the rear. Someday I'd like to install a 200R4 transmission for a little more top-end/freeway running, but I've got the turbo 350 in the car that works great, and a spare rebuilt turbo 350 just waiting in the wings for when I break the one in the car.
I'm hoping for a new job this year that will leave my weekends free to have fun instead of work.
Good luck,
Jeff
