LS2 403 D1SC Procharged 'street driver'.
Proceeded to cut the valve seats in a Sunnen VGS-20 guide and seat machine with some special radius seat cutters that matched the AFR seat angles to a tee!
I attached a pic of the seat cutter I used on the exhaust which was a 35* top angle, 45* seat (.060" wide), 12mm radius into a 75* throat. This is a very common profile for an exhaust seat in a performance head.
The intake was a bit unique. The cutter shown is it.
For those of you unfamiliar with cylinder head work these modern day guide and seat machines use formed carbide tool bits with multiple angles formed into it that cut all 3, 5, or 7 angles into the seat at once. Many aftermarket cylinder head manufactures spend lots of time creating the best series of angles and widths for optimum flow and have proprietary cutters to do so. They are sometimes a real PITA for an average machine shop to duplicate without killing the head. Pick your shops cautiously!
I attached a pic of the seat cutter I used on the exhaust which was a 35* top angle, 45* seat (.060" wide), 12mm radius into a 75* throat. This is a very common profile for an exhaust seat in a performance head.
The intake was a bit unique. The cutter shown is it.
For those of you unfamiliar with cylinder head work these modern day guide and seat machines use formed carbide tool bits with multiple angles formed into it that cut all 3, 5, or 7 angles into the seat at once. Many aftermarket cylinder head manufactures spend lots of time creating the best series of angles and widths for optimum flow and have proprietary cutters to do so. They are sometimes a real PITA for an average machine shop to duplicate without killing the head. Pick your shops cautiously!
Last edited by helicoil; Jun 4, 2008 at 12:24 AM.
The seats turned out real well with less than .0012" run-out on the intake (big 2.080" diameter) and less than .0008" on the exhaust.
The Prussian blue shows the concentricity of the seat after hand lapping the valve into it. The Prussian blue also shows the position of the seat on the valve. This is a nice confirmation (aside from vacuum checking) that all will be well when it runs.
On race motors you want the valve seating right up against the margin for optimum airflow.
The AFR intake valves have a nice 30* backcut on them to pick up flow on the intake side.
The Prussian blue shows the concentricity of the seat after hand lapping the valve into it. The Prussian blue also shows the position of the seat on the valve. This is a nice confirmation (aside from vacuum checking) that all will be well when it runs.
On race motors you want the valve seating right up against the margin for optimum airflow.
The AFR intake valves have a nice 30* backcut on them to pick up flow on the intake side.
Last edited by helicoil; Jun 4, 2008 at 12:26 AM.
I used a 'centerless' valve grinder from Sunnen to reface the valves, same used by many Nascar engine shops. This grinder does a real nice job holding less than .0005" of run-out.
I also show here some of the tooling used to freshen the seats on the heads in the guide and seat machine.
I also show here some of the tooling used to freshen the seats on the heads in the guide and seat machine.
Last edited by helicoil; Jun 4, 2008 at 12:27 AM.
I needed to get the combustion chambers on these heads down to around 65 cc with my combo to achieve a 9.5:1 comp ratio. They came in just over 71.5cc.
At .006" per cc for a flat mill that would mean I would have to remove around .040" from the deck.
I put them into the rotary broach to the job and used a PCD (Polycrystalline dimaond) bit to do the job. This little jewel is over 200.00 but finishes the surface with a real nice Ra (roughness average). The black on the cutter is the diamond.
This is what is needed to have good head gasket seal between the cylinder head and block.
At .006" per cc for a flat mill that would mean I would have to remove around .040" from the deck.
I put them into the rotary broach to the job and used a PCD (Polycrystalline dimaond) bit to do the job. This little jewel is over 200.00 but finishes the surface with a real nice Ra (roughness average). The black on the cutter is the diamond.
This is what is needed to have good head gasket seal between the cylinder head and block.
I took .005" off at a time and then finished with a light .0015" cut to get a super smooth 16-19 Ra finsh on the head. To put this in perspective glass measures about 3-4 Ra. They look like a mirror when your done. Especially when you cut real nice quality 356 aluminum.
I ended up taking .042" per head.
I ended up taking .042" per head.
When I was done I hand deburred all the edges and the combustion chamber opening as they were all razor sharp and then cc'd them again.
I ended up right where I wanted to be, 65cc.
With a .040" x 4.130" Cometic and a .005"-.006" Negative deck and the -22cc Diamond piston I will be right at 9.71:1. If I choose to use a Felpro 1162 R-L. .053" x 4.175" I will be at 9.43:1.
I am waiting for the Patriot Gold Extreme springs to arrive and I will then measure the installed spring heights and set them accordingly to get Max open pressure without coil bind.
I used these on my AFR 205's on my stock LS1 and really liked them, especially for the money.
I ended up right where I wanted to be, 65cc.
With a .040" x 4.130" Cometic and a .005"-.006" Negative deck and the -22cc Diamond piston I will be right at 9.71:1. If I choose to use a Felpro 1162 R-L. .053" x 4.175" I will be at 9.43:1.
I am waiting for the Patriot Gold Extreme springs to arrive and I will then measure the installed spring heights and set them accordingly to get Max open pressure without coil bind.
I used these on my AFR 205's on my stock LS1 and really liked them, especially for the money.
Last edited by helicoil; Jun 4, 2008 at 12:29 AM.
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Verdad Gallardo Got back to it today. Needed to complete the cylinder heads.
Started out measuring installed stem heights after all my valvework was done.
Obviously a critical step in a 'quiet' valvetrain. The closer these are the more consistent the lifter pre-load will be from rocker arm to rocker arm. After a little valve tipping, all of my stem heights ended up between 2.00" and 2.005".
I then measured all my installed spring heights to get around 1.775"-1.780" for the Patriot Gold Extreme Springs I plan to run.
This required a .015" shim under the spring cup for the exhaust valves. The intakes only needed the spring cup thickness to achieve the desired installed height.
I checked all of the springs in the Rimac spring tester and at this height they will install at 150 lbs on the seat and have a little over 415 lbs open pressure.
Started out measuring installed stem heights after all my valvework was done.
Obviously a critical step in a 'quiet' valvetrain. The closer these are the more consistent the lifter pre-load will be from rocker arm to rocker arm. After a little valve tipping, all of my stem heights ended up between 2.00" and 2.005".
I then measured all my installed spring heights to get around 1.775"-1.780" for the Patriot Gold Extreme Springs I plan to run.
This required a .015" shim under the spring cup for the exhaust valves. The intakes only needed the spring cup thickness to achieve the desired installed height.
I checked all of the springs in the Rimac spring tester and at this height they will install at 150 lbs on the seat and have a little over 415 lbs open pressure.
Last edited by helicoil; Jun 8, 2008 at 12:02 AM.
After finishing up the head assembly I was back on the shortblock this afternoon.
Installed the windage tray, spacing it with the needed washers to clear the 4 inch arm.
I then went on to set the pressure relief in the oil pump. I did this by using .100" worth of shims. I have fairly tight clearances throughout the engine but want to be sure the oil pressure gauge is on the high side, you never know, the future could hold plans for selling this car and I don't want someone quamming over low oil pressure because it makes a few more ponies on a dyno or some ****. I keep telling myself this is not a race car!
Installed the windage tray, spacing it with the needed washers to clear the 4 inch arm.
I then went on to set the pressure relief in the oil pump. I did this by using .100" worth of shims. I have fairly tight clearances throughout the engine but want to be sure the oil pressure gauge is on the high side, you never know, the future could hold plans for selling this car and I don't want someone quamming over low oil pressure because it makes a few more ponies on a dyno or some ****. I keep telling myself this is not a race car!
I then sorted through the three oil pump O-rings that were in my lower gasket set choosing the tightest fitting one. Lubed it up nice and assembled the pickup on the pump before bolting it all to the engine and while I had the pump cover off I verified it was installed properly.
I also ended up helicoiling the oil pump mount bolts while the block was on the stand, I had a problem with these in the engine in my car when I head/cammed it so I took care of them now. The OE casting defintely does not like much over 20ft lbs of torque on these.
I also ended up helicoiling the oil pump mount bolts while the block was on the stand, I had a problem with these in the engine in my car when I head/cammed it so I took care of them now. The OE casting defintely does not like much over 20ft lbs of torque on these.
While I had the tap set out for the oil pump holes and went ahead and threaded the existing knock sensor location for the LS1 knock sensor thread pitch and size which is 10 x 1.5MM.
After that I centered up the oil pump housing with .002" feeler gauges all the way around to get it in the right spot before sinching it down.
After that I centered up the oil pump housing with .002" feeler gauges all the way around to get it in the right spot before sinching it down.
After getting the oil pump installed and torqued down I went ahead and installed the front and rear covers along with the seals using the Kentmoore tools.
These NEW seals fit really loose in the covers. You can almost push them in with your fingers. I liked the older drab Olive green seal they used on the LS1 when it first came out. I find it a good idea to use an anaerobic glue like Loctite 518 on the OD before installing them into the covers.
Another thing I noted was the unique rear seal, it is a 'reverse' lip and if you don't pay attention to the directions you surely could install it backwards based on that old dinosaur mentality (BBC's)
These NEW seals fit really loose in the covers. You can almost push them in with your fingers. I liked the older drab Olive green seal they used on the LS1 when it first came out. I find it a good idea to use an anaerobic glue like Loctite 518 on the OD before installing them into the covers.
Another thing I noted was the unique rear seal, it is a 'reverse' lip and if you don't pay attention to the directions you surely could install it backwards based on that old dinosaur mentality (BBC's)
Rear seal instructions reference a white dot that indicates the 'OUT' position when installing the seal.
I attached a copy of the instructions, who reads that stuff anyway?
These were short and sweet so I glanced at them.
I got out the silicon to use it in the only 4 places needed to when assembling one of these engines which is where the front cover meets the oil pan and block and where the rear cover meets the oil pan and block, just a little did the trick. After that I bolted the pan down being sure to not let the rear overhang the back of the block since it is the lower bellhousing mount also.
I was then ready to install the lifters after modding the lifter retainers buckets for fast oil drain down with a 1/2" drill bit.
The LS7 lifters had been soaking in oil overnight and were ready to install.
I attached a copy of the instructions, who reads that stuff anyway?
These were short and sweet so I glanced at them.
I got out the silicon to use it in the only 4 places needed to when assembling one of these engines which is where the front cover meets the oil pan and block and where the rear cover meets the oil pan and block, just a little did the trick. After that I bolted the pan down being sure to not let the rear overhang the back of the block since it is the lower bellhousing mount also.
I was then ready to install the lifters after modding the lifter retainers buckets for fast oil drain down with a 1/2" drill bit.
The LS7 lifters had been soaking in oil overnight and were ready to install.
After the lifters were installed I got out the Felpro 1162 R-L head gaskets, brake cleaned off the deck of the block and screwed in the ARP studs.
The 1162 Felpros are 4-layers and have a 4.175" bore diameter. The AFR heads come at 4.100" across the chamber so a minimum of a 4.130" gasket should be used to prevent overhang into the chamber. After the unshrouding I did on the heads I needed at least a 4.160" diameter, so the 1162 was my only choice.
I set the gaskets down noting the left and right side and FRONT stamped into the body without touching them as it was obvious extra care was taken when wrapped to avoid ruining the soft black top coat.
I then set the heads down and torqued the ARP studs to the new recommended torque spec of 80ft lbs.
I also ended up getting the valley plate down as well today, but that was it.
Now it looks like where alot of the other builds start here on the site. Just call up the vendor and get you one.
More coming........
The 1162 Felpros are 4-layers and have a 4.175" bore diameter. The AFR heads come at 4.100" across the chamber so a minimum of a 4.130" gasket should be used to prevent overhang into the chamber. After the unshrouding I did on the heads I needed at least a 4.160" diameter, so the 1162 was my only choice.
I set the gaskets down noting the left and right side and FRONT stamped into the body without touching them as it was obvious extra care was taken when wrapped to avoid ruining the soft black top coat.
I then set the heads down and torqued the ARP studs to the new recommended torque spec of 80ft lbs.
I also ended up getting the valley plate down as well today, but that was it.
Now it looks like where alot of the other builds start here on the site. Just call up the vendor and get you one.
More coming........
R&r I was waiting on my Yank PY3400 to come back from having the torque converter clutch inspected to mate back up with my FLT Level 5 4l65e.
Got the engines swapped around and the NEW 403 LS2 installed onto the K-memeber and the trans bolted back up mid-week
I also have been waiting on my SDCE tensioner to arrive and started getting it installed today.
I hope to have it all the engine re-installed by Monday. Still waiting on some other misc (MAP sensor and fuel line) and have to install the rest of the Procharger 4.5" intercooler set-up and some gauges, etc
Got the engines swapped around and the NEW 403 LS2 installed onto the K-memeber and the trans bolted back up mid-week
I also have been waiting on my SDCE tensioner to arrive and started getting it installed today.
I hope to have it all the engine re-installed by Monday. Still waiting on some other misc (MAP sensor and fuel line) and have to install the rest of the Procharger 4.5" intercooler set-up and some gauges, etc
Progress Moving right along......
Been debating whether or not to go Speed Density or stick with the MAF. This area isn't really my strong point still learning. Seems to depend who you talk to, although I read an awful lot when I was H/C that the MAF dies about 500RWHP. So I not really sure how a tuner would compensate for it and leave it there.
I need to figure it out before it goes back up so I can change that MAP which would be a PITA later on after the fact if I changed my mind.
Took me about 45 minutes of messing around with that SDCE tensioner to figure it all out with the adjustment and belt routing. All in all it seems pretty nice, except for the hack grind job they did on the tensioner. You'd think for that kind of money it would be a little nicer, Oh well, as long as it is effective which it has proven to be on most people's cars. Kinda odd you get charged another 38.00 bucks on top of 695.00 for a tool which works but isn't exactly a precision fit over the tensioner, you'll bust your knuckles if you aren't using two hands which then makes it hard for you to slip the belt over the bottom pulley and that is out of the car on the floor.
Had to stop and run and get some NEW length belts for the 10% underdrive ATI damper which were longer than the ones I had on the 25% underdrive pulley and shorter than the stock ones I had. Started to get a collection of serpentine belts for this car.
I need to get some spacers to go underneath my FAST rails with the Siemens 60# installed, they are just a little taller than my 37lb Lucas injectors I had in there prior.
Few other odds and ends.
Hopefully be installing the engine and trans by the weekend, then I can move onto the gauges and intercoolers/piping and fans.
Been debating whether or not to go Speed Density or stick with the MAF. This area isn't really my strong point still learning. Seems to depend who you talk to, although I read an awful lot when I was H/C that the MAF dies about 500RWHP. So I not really sure how a tuner would compensate for it and leave it there.
I need to figure it out before it goes back up so I can change that MAP which would be a PITA later on after the fact if I changed my mind.
Took me about 45 minutes of messing around with that SDCE tensioner to figure it all out with the adjustment and belt routing.
All in all it seems pretty nice, except for the hack grind job they did on the tensioner. You'd think for that kind of money it would be a little nicer, Oh well, as long as it is effective which it has proven to be on most people's cars. Kinda odd you get charged another 38.00 bucks on top of 695.00 for a tool which works but isn't exactly a precision fit over the tensioner, you'll bust your knuckles if you aren't using two hands which then makes it hard for you to slip the belt over the bottom pulley and that is out of the car on the floor.Had to stop and run and get some NEW length belts for the 10% underdrive ATI damper which were longer than the ones I had on the 25% underdrive pulley and shorter than the stock ones I had. Started to get a collection of serpentine belts for this car.
I need to get some spacers to go underneath my FAST rails with the Siemens 60# installed, they are just a little taller than my 37lb Lucas injectors I had in there prior.
Few other odds and ends.
Hopefully be installing the engine and trans by the weekend, then I can move onto the gauges and intercoolers/piping and fans.
