new Race car project
07-08-2017, 05:53 AM
#1
Racer
Thread Starter
new Race car project
After a couple of years of 911 racing (996cup/997cup/964rsr) I have decided to come back to transaxle porsche's . I built and raced a 968 turbo rs replica a couple of years ago . Now i have made a partnership with Jan Mertens @dutchrennsport to built a 951 racecar . Jan has collected a huge pile of trick 951 parts over the years but he's missing the time to finnish the project .
The plan is to build a 951 that meets the regulations of the local Porsche club and the "youngtimers" this means in it has to have an 8v 2.5 liter engine and an h pattern gearbox .
Now for my question: I want to go for an solid lifter setup an the CR of 9/1 . I also want to use ITB's . Im trying to figure out what kind of camshaft i could best use for this ??? I hope someone can help me with some data on cam profiles .
The plan is to build a 951 that meets the regulations of the local Porsche club and the "youngtimers" this means in it has to have an 8v 2.5 liter engine and an h pattern gearbox .
Now for my question: I want to go for an solid lifter setup an the CR of 9/1 . I also want to use ITB's . Im trying to figure out what kind of camshaft i could best use for this ??? I hope someone can help me with some data on cam profiles .
07-08-2017, 12:21 PM
#2
Race Car
What are your power goals?
How much boost are you planning on running?
Will you be removing the AFM?
In the US, many of us have had good luck with well known builder Jon Milledge.
Spend some time on his site and have a look around maybe. Notice there are valve and valve spring suggestions with many of the cams.
http://jonmilledgeengineering.com
How much boost are you planning on running?
Will you be removing the AFM?
In the US, many of us have had good luck with well known builder Jon Milledge.
Spend some time on his site and have a look around maybe. Notice there are valve and valve spring suggestions with many of the cams.
http://jonmilledgeengineering.com
07-08-2017, 09:34 PM
#4
Drifting
Can you use a 2.7 head with a de-stroked 2.5 crankshaft (opposite of the stroker hybrid crankshafts) using Mitsubishi eagle connecting rods in a 104mm block to maintain the 8v head and 2.5L displacement requirements?
07-08-2017, 10:47 PM
#5
Rennlist Member
Why build it when you can buy it? It's already built. The motor has very limited hours run time on it. Will be in virtually brand new condition.
https://rennlist.com/forums/944-turb...e-refresh.html
Going back to the workshop for full refresh. Has reached over 500whp and revs out to 8000rpm+. Perfect for your application Filip!!
Can be supplied w/ custom intake that fits the billet inlet flange. Can be supplied with 4-1 coated headers.
Partial engine description from the builder Neil Harvey of Performance Developments.
"The Piston (Custom designed forged CPs) bore is 102.0mm. I have gone with the shortest Compression height I can go with on their Forging and keeping the pin out of the Oil Ring groove. This makes the Piston just a little lighter than having to run a steel support ring under the Lower Oil rail. The comp height worked out at 32.40mm. The stock compression height is 40.50 I think. The Pin diameter is 21.00mm and DLC coated.. The Stock pin is 24.0mm. I have gone with a thin ring package and lateral ported (gas) the top ring to help with the sealing. The 2nd ring is a Napier. The rings are steel, titanium nitrided with a 3 piece Oil package. The Piston total weight calculates out at 324.0grams.
MPS is 21.04 m/sec (4141.73 FPM). I have the max accel numbers (m/sec/sec) in the file and the calculated g numbers, both +ve and –ve. Remember the greatest acceleration the Piston sees is at TDC and BDC. Stock MPS is 17.88, (3520.50 FPM) at 6800 RPM. We are still really safe at 8000 RPM.
The Rod is 6.206” (157.630mm) CCL. The stock rod is 5.9055” (150.00mm). This slows down the Piston acceleration down some at an RPM of 8000. It also takes some side loading off the Piston skirt and Cylinder wall. The rod calculates out at 689.00 grams. 466gtrams rotating and 223 grams reciprocating. A stock Rod at 150.00mm long is over 800 grams I think.
The Block has a Deck Plate, steel liners with 9/16” head studs. The girdle is doweled. The Block was a NA block that ran the old style fixed belt tensioner. We have modified it to take the late style tensioner. Piston Oiling valves are fitted.
The head is ported both sides, with 49.00mm Intake Valves and 43.50mm Exhaust valves. Our race valve springs with Titanium Retainers and locks. Stainless Exhaust studs are fitted. I am making stepped head washers to use with the 9/16: head studs. Cam is ours with solid followers."
Here's a brief in car video showing how it can rev safely to 8000+ rpm.
https://rennlist.com/forums/944-turb...e-refresh.html
Going back to the workshop for full refresh. Has reached over 500whp and revs out to 8000rpm+. Perfect for your application Filip!!
Can be supplied w/ custom intake that fits the billet inlet flange. Can be supplied with 4-1 coated headers.
Partial engine description from the builder Neil Harvey of Performance Developments.
"The Piston (Custom designed forged CPs) bore is 102.0mm. I have gone with the shortest Compression height I can go with on their Forging and keeping the pin out of the Oil Ring groove. This makes the Piston just a little lighter than having to run a steel support ring under the Lower Oil rail. The comp height worked out at 32.40mm. The stock compression height is 40.50 I think. The Pin diameter is 21.00mm and DLC coated.. The Stock pin is 24.0mm. I have gone with a thin ring package and lateral ported (gas) the top ring to help with the sealing. The 2nd ring is a Napier. The rings are steel, titanium nitrided with a 3 piece Oil package. The Piston total weight calculates out at 324.0grams.
MPS is 21.04 m/sec (4141.73 FPM). I have the max accel numbers (m/sec/sec) in the file and the calculated g numbers, both +ve and –ve. Remember the greatest acceleration the Piston sees is at TDC and BDC. Stock MPS is 17.88, (3520.50 FPM) at 6800 RPM. We are still really safe at 8000 RPM.
The Rod is 6.206” (157.630mm) CCL. The stock rod is 5.9055” (150.00mm). This slows down the Piston acceleration down some at an RPM of 8000. It also takes some side loading off the Piston skirt and Cylinder wall. The rod calculates out at 689.00 grams. 466gtrams rotating and 223 grams reciprocating. A stock Rod at 150.00mm long is over 800 grams I think.
The Block has a Deck Plate, steel liners with 9/16” head studs. The girdle is doweled. The Block was a NA block that ran the old style fixed belt tensioner. We have modified it to take the late style tensioner. Piston Oiling valves are fitted.
The head is ported both sides, with 49.00mm Intake Valves and 43.50mm Exhaust valves. Our race valve springs with Titanium Retainers and locks. Stainless Exhaust studs are fitted. I am making stepped head washers to use with the 9/16: head studs. Cam is ours with solid followers."
Here's a brief in car video showing how it can rev safely to 8000+ rpm.
Last edited by 333pg333; 07-08-2017 at 11:09 PM.
07-09-2017, 11:01 AM
#7
Awesome video Patrick. I finally watched it.
flipo you have my vote to buy it
flipo you have my vote to buy it
Why build it when you can buy it? It's already built. The motor has very limited hours run time on it. Will be in virtually brand new condition.
https://rennlist.com/forums/944-turb...e-refresh.html
Going back to the workshop for full refresh. Has reached over 500whp and revs out to 8000rpm+. Perfect for your application Filip!!
Can be supplied w/ custom intake that fits the billet inlet flange. Can be supplied with 4-1 coated headers.
Partial engine description from the builder Neil Harvey of Performance Developments.
"The Piston (Custom designed forged CPs) bore is 102.0mm. I have gone with the shortest Compression height I can go with on their Forging and keeping the pin out of the Oil Ring groove. This makes the Piston just a little lighter than having to run a steel support ring under the Lower Oil rail. The comp height worked out at 32.40mm. The stock compression height is 40.50 I think. The Pin diameter is 21.00mm and DLC coated.. The Stock pin is 24.0mm. I have gone with a thin ring package and lateral ported (gas) the top ring to help with the sealing. The 2nd ring is a Napier. The rings are steel, titanium nitrided with a 3 piece Oil package. The Piston total weight calculates out at 324.0grams.
MPS is 21.04 m/sec (4141.73 FPM). I have the max accel numbers (m/sec/sec) in the file and the calculated g numbers, both +ve and –ve. Remember the greatest acceleration the Piston sees is at TDC and BDC. Stock MPS is 17.88, (3520.50 FPM) at 6800 RPM. We are still really safe at 8000 RPM.
The Rod is 6.206” (157.630mm) CCL. The stock rod is 5.9055” (150.00mm). This slows down the Piston acceleration down some at an RPM of 8000. It also takes some side loading off the Piston skirt and Cylinder wall. The rod calculates out at 689.00 grams. 466gtrams rotating and 223 grams reciprocating. A stock Rod at 150.00mm long is over 800 grams I think.
The Block has a Deck Plate, steel liners with 9/16” head studs. The girdle is doweled. The Block was a NA block that ran the old style fixed belt tensioner. We have modified it to take the late style tensioner. Piston Oiling valves are fitted.
The head is ported both sides, with 49.00mm Intake Valves and 43.50mm Exhaust valves. Our race valve springs with Titanium Retainers and locks. Stainless Exhaust studs are fitted. I am making stepped head washers to use with the 9/16: head studs. Cam is ours with solid followers."
Here's a brief in car video showing how it can rev safely to 8000+ rpm.
https://www.youtube.com/watch?v=3ABxfBEuqK4
https://rennlist.com/forums/944-turb...e-refresh.html
Going back to the workshop for full refresh. Has reached over 500whp and revs out to 8000rpm+. Perfect for your application Filip!!
Can be supplied w/ custom intake that fits the billet inlet flange. Can be supplied with 4-1 coated headers.
Partial engine description from the builder Neil Harvey of Performance Developments.
"The Piston (Custom designed forged CPs) bore is 102.0mm. I have gone with the shortest Compression height I can go with on their Forging and keeping the pin out of the Oil Ring groove. This makes the Piston just a little lighter than having to run a steel support ring under the Lower Oil rail. The comp height worked out at 32.40mm. The stock compression height is 40.50 I think. The Pin diameter is 21.00mm and DLC coated.. The Stock pin is 24.0mm. I have gone with a thin ring package and lateral ported (gas) the top ring to help with the sealing. The 2nd ring is a Napier. The rings are steel, titanium nitrided with a 3 piece Oil package. The Piston total weight calculates out at 324.0grams.
MPS is 21.04 m/sec (4141.73 FPM). I have the max accel numbers (m/sec/sec) in the file and the calculated g numbers, both +ve and –ve. Remember the greatest acceleration the Piston sees is at TDC and BDC. Stock MPS is 17.88, (3520.50 FPM) at 6800 RPM. We are still really safe at 8000 RPM.
The Rod is 6.206” (157.630mm) CCL. The stock rod is 5.9055” (150.00mm). This slows down the Piston acceleration down some at an RPM of 8000. It also takes some side loading off the Piston skirt and Cylinder wall. The rod calculates out at 689.00 grams. 466gtrams rotating and 223 grams reciprocating. A stock Rod at 150.00mm long is over 800 grams I think.
The Block has a Deck Plate, steel liners with 9/16” head studs. The girdle is doweled. The Block was a NA block that ran the old style fixed belt tensioner. We have modified it to take the late style tensioner. Piston Oiling valves are fitted.
The head is ported both sides, with 49.00mm Intake Valves and 43.50mm Exhaust valves. Our race valve springs with Titanium Retainers and locks. Stainless Exhaust studs are fitted. I am making stepped head washers to use with the 9/16: head studs. Cam is ours with solid followers."
Here's a brief in car video showing how it can rev safely to 8000+ rpm.
https://www.youtube.com/watch?v=3ABxfBEuqK4
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07-10-2017, 03:50 AM
#8
Rennlist Member
I can't imagine a better motor for a 2.5ltr restricted series. ;-)
