This might be a helpfull topic for people who want to build Tomei solid lifters and solid lifter profile cams. I've been working on these for a while and found several problems on the way that made the setup very difficult, and therefore worth explaining. I'm Dutch so please don't mind my spelling:slap:
I'll start with some general info on these cams.
The Tomei procam solid lifter cams are considered the best for the vg30, ca18 and rb20. This is cause the stock hydraulic valve lifters are replaced by lightweight (about 40% less weight) solid lifters. The weight reduction allows for a faster opening and closing rate and therefore more lift overall over the opening period. The problem with these solid lifters is that they require a clearence setup with shims that are sold by Tomei.
This is a picture of a solid lifter and 2 shims. Notice how thin the walls are, all part of the weight reduction. The shim slides over the lifter to prevent it from coming loose.
A comparison picture of a stock intake cam and a procam 260* 10,25mm lift. Notice the smaller radius of the cam. Stock is 32mm, Tomei is 29mm. Tomei designed their cams this way so no head grinding is required. The solid lifters are therefore also 1,5mm taller then the stock hydraulic lifters. It is said that decreasing the base circle of the cam may weaken the cam, but this only applies when the base circle is made smaller then the cam 'stem' itself. As you can see, this is no problem as the 'stem' is about 28mm.
Tomei sells shims ranging from 1,70 to 3,00mm in steps of 0,02mm. The size you'll need depends on how old your stuff is and if your valve seats have been regrind. The intake cams require 0,45mm and the exhaust 0,38mm clearence. Why the exhaust requires less is not known to me. The clearence is quite large, most engines are somewhere in the 0,15-0,20mm range. The profile of the cams however allows for a cushion that brings the lobe smoothly in contact with the lifter to avoid wear.
Since Tomei allows for just 0,01mm difference in clearence from the given values it is important that you use feeler gauges in steps of 0,01mm for a correct measurement of the clearence. I bought these from a Dutch store on the internet;
Stuff that influences the clearence
I performed several tests to make sure there are no differences. But there were.
Temperature
At first I took the clearences with the engine in my garage with subzero temperatures (-2* C). Next I took the same head in the living room (17* C) and let it warm up for a while. No less then 0,05mm increase in clearence was found. Since most manufacturers rate their parts to be measured at shop temperatures (around 17* C) I decided to perform everything in the living room.
Head bolted or not?
When one of the heads was bolted to the block I noticed a clearence increase of about 0,01mm. Not much but I think it's better to perform the tests with the heads on to be 100% sure. The head studs were ARP and a Tomei steel gasket was used for the record.
Cam bolted to the head or not?
With one of the cams fully bolted in place I found no difference in clearence vs if the cam was not bolted and pushed in position by hand. So don't bolt the cam down, it'll just wear out the bolts and head.
Tomei sucks!
Don't think just cause they're Japanese they take their work as serious as many Japanese car manufacturers. A friend of mine had been working on the solid lifters before and over and over he got different clearences. I found out why.
At one moment I was testing if the clearences measured one day were the same the next day, with 2 different lifters with the same shims. They weren't, but in a particular way. One valve had 0,01mm added clearence, the other 0,01mm. What was wrong was that the lifters appeared to be of different sizes, no less then 0,07mm difference was found in between the largest and smallest.
Here is a sheet I made with all sizes and a close up of the caliper;
What I recommend you to do is measure each individual lifter and sort them to size. As you can see in the pic I used a caliper with 2 shims stacked, one placed correctly and the other with it's back against it. This works very well and avoids differences between recordings. A micrometer works even better but I didn't have one.
What shims?
A new head will most likely use thicker shims then a used head. One new vg30dett head I measured had almost identical clearences for all valves and required shims of around 2,68mm for the intake and 2,75mm for the exhaust. However, due to the large variations in lifter height it is important to take this into account for ordering shims.
My own head with grinded valve seats required slightly smaller shims, ranging from 2,44mm to 2,70mm.
To make correct measurements you must use the thinnest feeler gauges you have. However, this requires a range of shims to be used. What I reccomend is to order 2 pieces of the following sizes; 2,30mm, 2,60mm and 3,00mm. Unless your seats have been ground excessively there should be no valve deep enough to go beyond the 2,30mm shim.
How to measure clearence
I do not recommend the use of moly lube and other fat substances, regular oil works much better and can't influence the recordings since it flows much easier.
The clearence should be measured with 2 lifters at a time for each pair of inlet/exhaust valves. Ensure you use 2 identical lifters and shims. Push the cam in position by hand with the lobe facing upwards. If a feeler gauge of 0,07mm slides in very easy but a 0,08mm with a bit of a push I note this as 0,075mm.
Make a sheet and record each clearence. Note what shim was used and what size the lifter was. You can use lifters of various sizes to compensate for any large fluctuations between valve pairs.
Why not cut the stems?
SPLparts (where I bought my setup) recommended 24 3,00mm shims and have the valve tips shortened by a shop.
However, there are 2 reasons why you don't wanna do this. First it takes a lot more time, and due to the complications thanks to the various lifter sizes the mechanic has to work hours to make it all fit. And you're paying all the time. Worse, a lazy mechanic may swap lifters and upset everything. If he grinds the valves too far they can be thrown away.
The other reason is that grinding valve stem tips reduced the strenght of the valve. You really don't wanna have a dropped valve. My shop did not want to grind my valves as he needed to remove almost 0,50mm on some valves.
Hope this helps. I will be trying to update it with more info, mostly on the cam profiles of stock vs procam.
This might be a helpfull topic for people who want to build Tomei solid lifters and solid lifter profile cams. I've been working on these for a while and found several problems on the way that made the setup very difficult, and therefore worth explaining. I'm Dutch so please don't mind my spelling:slap:
I'll start with some general info on these cams.
The Tomei procam solid lifter cams are considered the best for the vg30, ca18 and rb20. This is cause the stock hydraulic valve lifters are replaced by lightweight (about 40% less weight) solid lifters. The weight reduction allows for a faster opening and closing rate and therefore more lift overall over the opening period. The problem with these solid lifters is that they require a clearence setup with shims that are sold by Tomei.
This is a picture of a solid lifter and 2 shims. Notice how thin the walls are, all part of the weight reduction. The shim slides over the lifter to prevent it from coming loose.
A comparison picture of a stock intake cam and a procam 260* 10,25mm lift. Notice the smaller radius of the cam. Stock is 32mm, Tomei is 29mm. Tomei designed their cams this way so no head grinding is required. The solid lifters are therefore also 1,5mm taller then the stock hydraulic lifters. It is said that decreasing the base circle of the cam may weaken the cam, but this only applies when the base circle is made smaller then the cam 'stem' itself. As you can see, this is no problem as the 'stem' is about 28mm.
Tomei sells shims ranging from 1,70 to 3,00mm in steps of 0,02mm. The size you'll need depends on how old your stuff is and if your valve seats have been regrind. The intake cams require 0,45mm and the exhaust 0,38mm clearence. Why the exhaust requires less is not known to me. The clearence is quite large, most engines are somewhere in the 0,15-0,20mm range. The profile of the cams however allows for a cushion that brings the lobe smoothly in contact with the lifter to avoid wear.
Since Tomei allows for just 0,01mm difference in clearence from the given values it is important that you use feeler gauges in steps of 0,01mm for a correct measurement of the clearence. I bought these from a Dutch store on the internet;
Stuff that influences the clearence
I performed several tests to make sure there are no differences. But there were.
Temperature
At first I took the clearences with the engine in my garage with subzero temperatures (-2* C). Next I took the same head in the living room (17* C) and let it warm up for a while. No less then 0,05mm increase in clearence was found. Since most manufacturers rate their parts to be measured at shop temperatures (around 17* C) I decided to perform everything in the living room.
Head bolted or not?
When one of the heads was bolted to the block I noticed a clearence increase of about 0,01mm. Not much but I think it's better to perform the tests with the heads on to be 100% sure. The head studs were ARP and a Tomei steel gasket was used for the record.
Cam bolted to the head or not?
With one of the cams fully bolted in place I found no difference in clearence vs if the cam was not bolted and pushed in position by hand. So don't bolt the cam down, it'll just wear out the bolts and head.
Tomei sucks!
Don't think just cause they're Japanese they take their work as serious as many Japanese car manufacturers. A friend of mine had been working on the solid lifters before and over and over he got different clearences. I found out why.
At one moment I was testing if the clearences measured one day were the same the next day, with 2 different lifters with the same shims. They weren't, but in a particular way. One valve had 0,01mm added clearence, the other 0,01mm. What was wrong was that the lifters appeared to be of different sizes, no less then 0,07mm difference was found in between the largest and smallest.
Here is a sheet I made with all sizes and a close up of the caliper;
What I recommend you to do is measure each individual lifter and sort them to size. As you can see in the pic I used a caliper with 2 shims stacked, one placed correctly and the other with it's back against it. This works very well and avoids differences between recordings. A micrometer works even better but I didn't have one.
What shims?
A new head will most likely use thicker shims then a used head. One new vg30dett head I measured had almost identical clearences for all valves and required shims of around 2,68mm for the intake and 2,75mm for the exhaust. However, due to the large variations in lifter height it is important to take this into account for ordering shims.
My own head with grinded valve seats required slightly smaller shims, ranging from 2,44mm to 2,70mm.
To make correct measurements you must use the thinnest feeler gauges you have. However, this requires a range of shims to be used. What I reccomend is to order 2 pieces of the following sizes; 2,30mm, 2,60mm and 3,00mm. Unless your seats have been ground excessively there should be no valve deep enough to go beyond the 2,30mm shim.
How to measure clearence
I do not recommend the use of moly lube and other fat substances, regular oil works much better and can't influence the recordings since it flows much easier.
The clearence should be measured with 2 lifters at a time for each pair of inlet/exhaust valves. Ensure you use 2 identical lifters and shims. Push the cam in position by hand with the lobe facing upwards. If a feeler gauge of 0,07mm slides in very easy but a 0,08mm with a bit of a push I note this as 0,075mm.
Make a sheet and record each clearence. Note what shim was used and what size the lifter was. You can use lifters of various sizes to compensate for any large fluctuations between valve pairs.
Why not cut the stems?
SPLparts (where I bought my setup) recommended 24 3,00mm shims and have the valve tips shortened by a shop.
However, there are 2 reasons why you don't wanna do this. First it takes a lot more time, and due to the complications thanks to the various lifter sizes the mechanic has to work hours to make it all fit. And you're paying all the time. Worse, a lazy mechanic may swap lifters and upset everything. If he grinds the valves too far they can be thrown away.
The other reason is that grinding valve stem tips reduced the strenght of the valve. You really don't wanna have a dropped valve. My shop did not want to grind my valves as he needed to remove almost 0,50mm on some valves.
Hope this helps. I will be trying to update it with more info, mostly on the cam profiles of stock vs procam.
-Rutger