Patrick's build thread. (IT RUNS!)
04-05-2016, 12:45 AM
#1141
Rennlist Member
Thread Starter
Been quite a long time between posts on the 16v motor. There have been a few design changes and part delays along the way also.
Block has been Nikasil treated for extra hardness. The main studs holes have been additionally strengthened by a version of a Time Sert. With the extra torque loading on these 25yr old blocks and larger headstuds it was deemed a worthwhile modification. We did something similar down here with the 2.5 8v racemotor.
Certain parts such as bearings and rings have been coated with an anti friction coating used by Honda in F1. Ultimately we would like to use a custom crank but at this stage it is a stock crank with some lightening (approx 6 lbs I think) and has been modified to a 94mm offset grind to enhance torque. The main issue we have with our car is the stock Syncromesh 6 speed vs competitors with Sequential Transmissions which are a massive improvement. So we need to maximise torque to give us a lot of drive off the corners and possibly reduce the amount of gear changes. The old 3.1 8v had about 720Nm of tq to the rear wheels which is a lot. Hopefully the 16v motor can give us something similar.
The cams are being ground now and they've been designed more around mid range than totally upper rpm. The valve train will be capable of spinning out to well over 9000rpm but we'll not get up that high. Not quite sure where we'll set the rpm cut. Perhaps around about 8000rpm and a soft cut rather than the hard cut we've been running on the previous motors. Just a bit more friendly to the components. The head was flowed to a max of 370cfm at 25". It was decided to not go overboard on the exhaust side to try and induce more rapid response both on and off boost. Potentially the superior head and 3.2 capacity should ensure that we can reach similar power (say 550whp) at lower boost than before therefore enhancing reliability. It will be running adjustable twin cam wheels at the front of the motor with a modified tensioner to increase belt wrap on the custom crank pulley.
There will be a custom ATI damper to quell harmonics but also incorporate a pulley to run the alt belt off. The idea is to shorten the parts hanging off the nose of the crank to further reduce the possibility of crank distortion which we felt was the likely reason for the failure of the 3.1 motor. The balance shafts have been removed. We felt that the main purpose for the balance shafts is to deal with harmonics in the mid range. In addition, they were designed and built with the stock motor all those years ago. With every single part in the new motor changing in weight, size, balance etc it was felt that they were almost redundant.
The head will be sealed via a custom Cometic gasket designed to run with custom Garlock sealing rings. Due to some changes in their company structure these Garlocks have taken many months to procure. Hopefully they do the trick combined with the possible lower boost needed.
I went down the path of changing to a Borg Warner twin scroll EFR turbo. I would really like to change to one of these, however budget is tight and this would have added about $10k to the build with changes to the headers, X overs, turbo and I would have also changed the exhaust to a larger than 3" straight through system. So reluctantly we decided to keep all the externals that we have and at least we can compare this motor to the 2 previous ones apples to apples as such. We will move up to the largest turbine housing for the GTX3582r and therefore our setup will be quite similar to Gustaf's motor which achieved very good figures on the dyno. I'm not expecting quite the same figures on the basis of expected pessimism but even 80% of what he got will be very pleasing. The main difference will probably be the length of inlet runners. His are quite a bit shorter. Due to budget and also packaging constraints I have decided that we will probably just modify the intake we have now. Enhancing the tq with the longer runners won't be such a bad thing.
The rods are custom design Carillo and pistons are short skirt CP. Obviously considerably lighter than stock.
The stock water pump is being blocked off and we will be using a Davies-Craig electric product.
The block and head will be sent down to us within the next 10 days. We can start working on fitting the motor and rejigging the headers and inlet. Also fit the water pump. The cams and drive pulleys plus tensioner will follow shortly afterwards. Hopefully not too long to get this motor in the car and tuned. More pics to follow.
Block has been Nikasil treated for extra hardness. The main studs holes have been additionally strengthened by a version of a Time Sert. With the extra torque loading on these 25yr old blocks and larger headstuds it was deemed a worthwhile modification. We did something similar down here with the 2.5 8v racemotor.
Certain parts such as bearings and rings have been coated with an anti friction coating used by Honda in F1. Ultimately we would like to use a custom crank but at this stage it is a stock crank with some lightening (approx 6 lbs I think) and has been modified to a 94mm offset grind to enhance torque. The main issue we have with our car is the stock Syncromesh 6 speed vs competitors with Sequential Transmissions which are a massive improvement. So we need to maximise torque to give us a lot of drive off the corners and possibly reduce the amount of gear changes. The old 3.1 8v had about 720Nm of tq to the rear wheels which is a lot. Hopefully the 16v motor can give us something similar.
The cams are being ground now and they've been designed more around mid range than totally upper rpm. The valve train will be capable of spinning out to well over 9000rpm but we'll not get up that high. Not quite sure where we'll set the rpm cut. Perhaps around about 8000rpm and a soft cut rather than the hard cut we've been running on the previous motors. Just a bit more friendly to the components. The head was flowed to a max of 370cfm at 25". It was decided to not go overboard on the exhaust side to try and induce more rapid response both on and off boost. Potentially the superior head and 3.2 capacity should ensure that we can reach similar power (say 550whp) at lower boost than before therefore enhancing reliability. It will be running adjustable twin cam wheels at the front of the motor with a modified tensioner to increase belt wrap on the custom crank pulley.
There will be a custom ATI damper to quell harmonics but also incorporate a pulley to run the alt belt off. The idea is to shorten the parts hanging off the nose of the crank to further reduce the possibility of crank distortion which we felt was the likely reason for the failure of the 3.1 motor. The balance shafts have been removed. We felt that the main purpose for the balance shafts is to deal with harmonics in the mid range. In addition, they were designed and built with the stock motor all those years ago. With every single part in the new motor changing in weight, size, balance etc it was felt that they were almost redundant.
The head will be sealed via a custom Cometic gasket designed to run with custom Garlock sealing rings. Due to some changes in their company structure these Garlocks have taken many months to procure. Hopefully they do the trick combined with the possible lower boost needed.
I went down the path of changing to a Borg Warner twin scroll EFR turbo. I would really like to change to one of these, however budget is tight and this would have added about $10k to the build with changes to the headers, X overs, turbo and I would have also changed the exhaust to a larger than 3" straight through system. So reluctantly we decided to keep all the externals that we have and at least we can compare this motor to the 2 previous ones apples to apples as such. We will move up to the largest turbine housing for the GTX3582r and therefore our setup will be quite similar to Gustaf's motor which achieved very good figures on the dyno. I'm not expecting quite the same figures on the basis of expected pessimism but even 80% of what he got will be very pleasing. The main difference will probably be the length of inlet runners. His are quite a bit shorter. Due to budget and also packaging constraints I have decided that we will probably just modify the intake we have now. Enhancing the tq with the longer runners won't be such a bad thing.
The rods are custom design Carillo and pistons are short skirt CP. Obviously considerably lighter than stock.
The stock water pump is being blocked off and we will be using a Davies-Craig electric product.
The block and head will be sent down to us within the next 10 days. We can start working on fitting the motor and rejigging the headers and inlet. Also fit the water pump. The cams and drive pulleys plus tensioner will follow shortly afterwards. Hopefully not too long to get this motor in the car and tuned. More pics to follow.
04-05-2016, 04:35 AM
#1142
Pro
That is looking very awesome Patrick! Nice to see things are coming together for you. Keen to see what your monster can do with a 16V engine, I wish you the very best of luck with it!
)
04-05-2016, 04:54 AM
#1144
Rennlist Member
Thread Starter
Fish Oil...isn't everyone advocating this nowadays Mike?
04-05-2016, 05:24 AM
#1147
That's some nasty cfm on that head. Definitely want to see this dyno compared to your other engine and then to a couple of our counterparts with 16v turbos. I think with all that are happening finally we will get a whole lot more info........ Basically telling us what we already knew. Lol
04-05-2016, 06:59 AM
#1148
Rennlist Member
Very interesting. I like The waterpump mod, i was researching that a while ago for my other motor. Any pictures of that block off plate? Can more be produced ?
Will you run an electronic servo pump as well?
Love all these stroker builds.
Will you run an electronic servo pump as well?
Love all these stroker builds.
04-05-2016, 05:34 PM
#1152
Rennlist Member
Thread Starter
That's some nasty cfm on that head. Definitely want to see this dyno compared to your other engine and then to a couple of our counterparts with 16v turbos. I think with all that are happening finally we will get a whole lot more info........ Basically telling us what we already knew. Lol
Yes, squirters are there.
25" Shawn. He could have made it flow more but felt that this might put more strain on other components or involve changing components to superior ones. There's a limit to budget and our target is to improve upon the 3.1L motor but not necessarily double it sort of thing. The ports in the 968 heads are very large to begin. He modified them somewhat and we're running 41mm & 35mm valves.
04-05-2016, 10:20 PM
#1153
Rennlist Member
That number at 25" WC is a fantastic result. MM had previously posted these numbers:
944 4V / Full Porting / 41mm intake valve / 28" CFM
.100 114
.200 221
.300 323
.400 369
.500 383
944 4V / Full Porting / 41mm intake valve / 28" CFM
.100 114
.200 221
.300 323
.400 369
.500 383
04-06-2016, 01:08 AM
#1155
Rennlist Member
Thread Starter
Lower than your flow rates Rod but good enough for our objectives. So you're running no b/shafts or damper? I have the same one from RS Barn but the new one should be a little better in design.