3.875 x 4.125 sbc, do I want a 6" rod?

[redliner]

just checked- the offset 3.75 grind was 3.810- everything worked

I see.... cool... Oh and Mike just got back with cam reccomendation. I listed 1.7 rocker ratio and I need to verify if that is what he is figuring. He says for my 3300 lbs. 4-speed coupe 262/268@ .050, .421/.412,110

[steve316]

Redliner; 283 rod journal compStar csa6000cs2a2ah. they come with ARP 2000 7\16 bolts and weight 591g.

[redliner]

Redliner; 283 rod journal compStar csa6000cs2a2ah. they come with ARP 2000 7\16 bolts and weight 591g.

Thanks Steve, I will givem the hairy eyeball!

[danta]

MINE IS SHP 3.875 x 4.156 with Callies crank and 6" Compstar and Mahle powerpack .720 lift no small base circle(this is why i when 421 ) didnt needed to clearance anything.

What are the spec on yer cam if I might ask?

269-277 .450-.433 108

[rfoll]

I had plans to build a 3.785 stroke motor, and spent considerable time doing research to keep the costs down. In the end I bought a Dart built 415 from Competition Products. http://www.competitionproducts.com/Dart ... IFea40zWCg. It was not my first choice as far as the particular parts concerned, but it turned out to be the best deal. If I added up the costs for the parts and machine work, it would have cost me about $800 more to do it myself. The crank is also Compstar, and the pistons are HRC made by Ross. One of the plusses about this package is the Little M block. The down side was the necessity of pulling pistons to clearance the rods for my standard base circle solid roller cam. Be aware that Dart blocks use a main cap that reaches all the way to the pan rail and it was difficult to find a pan to fit it. Milodon was one of the few that guaranteed theirs would fit. They also require a taller lifter, so you may not be able to use what you have on hand. If you have access to free machine work, and use the SHP block, it can be done for much less money.

[bigjoe1]

Interesting thing about the small base curcle- I run 900 BC in all the raced engines I do - My sons 434 SB Chevy make 930 HP, and we turn it 8500, twice on every run down the drag strip- NOT A PROBLEM-- So much bull shit



JOE SHERMAN RACING

[redliner]

I had plans to build a 3.785 stroke motor, and spent considerable time doing research to keep the costs down. In the end I bought a Dart built 415 from Competition Products. http://www.competitionproducts.com/Dart ... IFea40zWCg. It was not my first choice as far as the particular parts concerned, but it turned out to be the best deal. If I added up the costs for the parts and machine work, it would have cost me about $800 more to do it myself. The crank is also Compstar, and the pistons are HRC made by Ross. One of the plusses about this package is the Little M block. The down side was the necessity of pulling pistons to clearance the rods for my standard base circle solid roller cam. Be aware that Dart blocks use a main cap that reaches all the way to the pan rail and it was difficult to find a pan to fit it. Milodon was one of the few that guaranteed theirs would fit. They also require a taller lifter, so you may not be able to use what you have on hand. If you have access to free machine work, and use the SHP block, it can be done for much less money.

I am in the research mode now, thanks for the heads up. I have been looking at them but want Howards crank and perhaps XD rods. Did you pull it down and measure things? How did it run/ leak down etc? What kind of power are you making with it? Heads/ cam?

[redliner]

Interesting thing about the small base curcle- I run 900 BC in all the raced engines I do - My sons 434 SB Chevy make 930 HP, and we turn it 8500, twice on every run down the drag strip- NOT A PROBLEM-- So much bull shit

Experience talks! Thanks Big Joe! I have a .900 base circle cam and have had 0 problems so far and your input confirms my thoughts....

JOE SHERMAN RACING

[Frankshaft]

^^^^^ and let me guess, it runs 9.20's at 2800 lbs??

[bigjoe1]

NO--- 8.70 at 2900 pounds


JOE SHERMAN RACING

[rfoll]

I had plans to build a 3.785 stroke motor, and spent considerable time doing research to keep the costs down. In the end I bought a Dart built 415 from Competition Products. http://www.competitionproducts.com/Dart ... IFea40zWCg. It was not my first choice as far as the particular parts concerned, but it turned out to be the best deal. If I added up the costs for the parts and machine work, it would have cost me about $800 more to do it myself. The crank is also Compstar, and the pistons are HRC made by Ross. One of the plusses about this package is the Little M block. The down side was the necessity of pulling pistons to clearance the rods for my standard base circle solid roller cam. Be aware that Dart blocks use a main cap that reaches all the way to the pan rail and it was difficult to find a pan to fit it. Milodon was one of the few that guaranteed theirs would fit. They also require a taller lifter, so you may not be able to use what you have on hand. If you have access to free machine work, and use the SHP block, it can be done for much less money.

I am in the research mode now, thanks for the heads up. I have been looking at them but want Howards crank and perhaps XD rods. Did you pull it down and measure things? How did it run/ leak down etc? What kind of power are you making with it? Heads/ cam?

My heads are the Brodix Track 1 Spec heads, got a great deal on them bare and did my own assembly. I'm not particularly happy with them, but they will be ok until I find the time for something else. With a 70 cc chamber and a thin mls gasket, static cr comes out to 10.35. The pistons are .025" in the hole, not what I would want but I'll save that issue for later. I'm using a Holly 300-25 Strip Dominator and an 800 double pumper. The cam is a Howards solid roller, 259/262/106. I have no idea what the HP is, and don't really care. Car is a 78 Skylark with 3.73 gears, 3500 lb. with me in it. Shifting at 6500 it runs about 11 flat at 121 mph.

[redliner]

I had plans to build a 3.785 stroke motor, and spent considerable time doing research to keep the costs down. In the end I bought a Dart built 415 from Competition Products. http://www.competitionproducts.com/Dart ... IFea40zWCg. It was not my first choice as far as the particular parts concerned, but it turned out to be the best deal. If I added up the costs for the parts and machine work, it would have cost me about $800 more to do it myself. The crank is also Compstar, and the pistons are HRC made by Ross. One of the plusses about this package is the Little M block. The down side was the necessity of pulling pistons to clearance the rods for my standard base circle solid roller cam. Be aware that Dart blocks use a main cap that reaches all the way to the pan rail and it was difficult to find a pan to fit it. Milodon was one of the few that guaranteed theirs would fit. They also require a taller lifter, so you may not be able to use what you have on hand. If you have access to free machine work, and use the SHP block, it can be done for much less money.

I am in the research mode now, thanks for the heads up. I have been looking at them but want Howards crank and perhaps XD rods. Did you pull it down and measure things? How did it run/ leak down etc? What kind of power are you making with it? Heads/ cam?

My heads are the Brodix Track 1 Spec heads, got a great deal on them bare and did my own assembly. I'm not particularly happy with them, but they will be ok until I find the time for something else. With a 70 cc chamber and a thin mls gasket, static cr comes out to 10.35. The pistons are .025" in the hole, not what I would want but I'll save that issue for later. I'm using a Holly 300-25 Strip Dominator and an 800 double pumper. The cam is a Howards solid roller, 259/262/106. I have no idea what the HP is, and don't really care. Car is a 78 Skylark with 3.73 gears, 3500 lb. with me in it. Shifting at 6500 it runs about 11 flat at 121 mph.

Ya that deeep hole is killin ya! .005 below deck for future clean up is what I am shooting for. That thing is haulin ass for several reasons!!! 3500lbs!!! 3.73!!! .025 down in the well...

[wyrmrider]

1.7 rockers
you will have to mock up your block and heads and clearance
ask mIke about 1.6 or 1.5 on the exhaust also about rocker vendors
whose rockers?
U have read and understand http://www.sbintl.com/tech_library/arti ... ometry.pdf
pass on any rockers that do not line up correctly hopefully the pushrod cup will be closely tangent to the pushrod as well as the lever end being tangent to the valve and both through the center of the trunion
avoid those shaped like this pushrod side-- T --valve stem side
center way down here
center of fulcrum must be in line with center of roller when that line is tangent to valve stem at half lift
cus the 1.7 are liable to take some extra care
ask Chris but are those heads set up for 1.7?
otherwise think about backset trunions to get the pushrod further away from the fulcrum (and the head/ block)
the longer roller arm gives a better motion, actually longer on both sides both work better
pushrod diameter- bigger the better and make sure the balls and cups match
good idea in the planning stage as as an add on is problematical

[redliner]

1.7 rockers
you will have to mock up your block and heads and clearance
ask mIke about 1.6 or 1.5 on the exhaust also about rocker vendors
whose rockers?
U have read and understand http://www.sbintl.com/tech_library/arti ... ometry.pdf
pass on any rockers that do not line up correctly hopefully the pushrod cup will be closely tangent to the pushrod as well as the lever end being tangent to the valve and both through the center of the trunion
avoid those shaped like this pushrod side-- T --valve stem side
center way down here
center of fulcrum must be in line with center of roller when that line is tangent to valve stem at half lift
cus the 1.7 are liable to take some extra care
ask Chris but are those heads set up for 1.7?
otherwise think about backset trunions to get the pushrod further away from the fulcrum (and the head/ block)
the longer roller arm gives a better motion, actually longer on both sides both work better
pushrod diameter- bigger the better and make sure the balls and cups match
good idea in the planning stage as as an add on is problematical

I set up my AFR heads several years ago with a prototype Miller Midlift rocker arm set up ( Jim and I spent mucho time on the phone setting up rockers for my AFR heads ( one of the first sets of Eliminator heads), where i had to do a bunch of ciphering and mill the stands.... what a headache. I am not set on 1.7 rockers. I run 1.65 intakes now and 1.6 ex. I was going to run Jesel sportsman shaft rockers and they come in 1.7 I will touch base with Mike on the rocker ratio before dropping the cash on the cam. P.S. I am using Crower backset rockers on my current heads.

[danta]

i choose 3.875 stroke because i have more choice of cam and i cant afford custom grind ,in canada they cost the double of a shelve cam.it is not because the smaller base of cam i only run 640# springs so a small base circle wont bind with this spring pressure.