Tubo charged T4 for a 1966 Porsche 912 - need advise
Posted: Sun Feb 07, 2016 3:16 pm
Hello everyone!
I have been cruzing this forum and thesamba for awhile in preparation for building an engine for a 1966 Porsche 912 my uncle gave me to restore. The 912 was parked in his backyard for many years and had a tree growing over the top of it when I first saw it. I asked him about it and he offered it to me to restore. I plan to start this summer as my Factory Five project will be complete.
I have built several Ford Windsor motors, but this is my first foray into the VW world. I think I'm at a place now where I have figured out the differences between the dizzying array of motor types, body types, cooling options and have been preparing a type4 build list. The 912 has no motor in it to rebuild and after looking at the different options I settled on the type 4 for a few reasons.
* Real Porsche engines are prohibitively expensive to build
* The 1976 912 had a 912 E model that actually used a 2.0L type 4 engine, so I know it fits
* The type4 bolts right up to the existing transaxle
* The type4's bottom end is supposedly bullet proof
* Going to a larger displacement appears to be relatively well supported
* From an originality perspective, the T4 isn't too far out of line considering the 912E
I picked up what appears to be a 1.8L type 4 from a friend for a very reasonable price. I have not removed the heads or split the case yet to see if it is actually a 1.8, or what changes may have already been made in the past.
I have also never built a turbo motor before, and I would really like to give this a shot. I have experience using Megasquirt ECU’s, and used a highly modified version to build the Ford 306 ITB motor that I used for my FactoryFive AC Cobra replica. I also converted my wifes 1969 Camaro to EFI using megasquirt.
Looking over the engine kit manufactures it looks like I can purchase a kit to bring the 1.8L to 2257cc without extra machining. Also, I am not sure the turbo would play as nice with a stroke longer than 78mm, and I really don’t think I need a bigger bore because the HP/torque should be way more than enough for me. I considered keeping it at 1800cc, but I could not find any forged piston 1.8L kits.
I was hoping that the more versed members in this forum might be able to look over my build plan and make sure that I have not missed anything, and that my plan is sound. I am definitely open to suggestions! My goal is to build a turbo motor that will see street use only. I want it to be reliable, but fun to drive. I know I will need to upgrade the gear set in the 601 transaxle as well to accommodate the new motor. I have only done enough research in this area to know that it can be done and that the parts are available.
So, here is my initial build list:
* 1.8L engine case
* Engine cleaned, and bore align checked (European Motorworks? HAM?)
* 2257cc forged engine kit from AA Pistons (Part#: EK 004 2257 JE) (cast iron not biral cylinders?) 96mm bore x 78mm stroke with forged JE pistons
* Dynamic balancing performed by AA Pistons – in addition to kit package
* Scat 20088 (c45 grind .507 lift, 298, 262 duration) cam – or Webcam 119
* Solid lifters (Scat or WebCam)
* Heads – Assuming the 1.8L heads I have can be rebuilt (by European Motorworks? HAM?):
** Larger valves – 36mm x 48mm? (need advice here!)
** Dual springs
** New valve guides
** Full port & polish
** 3 angle valve job
** Swivel valve adjuster kit (EMPI 4061)
** Solid rocker arm spacers to replace spring tensioner
Turbo’s I am considering (I plan to run 15PSI max):
* T28 (AKA “disco potato”) - sr20det
* TD05H – from Mitsubishi EVO9
* T04B – twinscroll option available and oil cooled only (my first choice ATM)
* GT3076R
As I mentioned above, I am a turbo novice so any recommendations here would be most helpful!
Notes:
* Max RPM 6500ish is plenty for me…I really don’t know how the type 4 revs?
* My research shows that a 914 flywheel, clutch and clutch plate should bolt right up?
* I will need to fabricate a motor mount
* I will fabricate my own exhaust and intake plumbing
* What compression ratio should I strive for? VW engines in general seem to run much lower compression ratios than I am used to on Ford V8’s?
* I will be running a DubShop hidden crank wheel for the crank VSS
* I will be running a DubShop mini cam sync for the cam VSS
* I will be running an intercooler
* Original pancake style cooling (more room for turbo plumbing and intercooler) I will need to do some fabrication here.
* Is the standard oil pump OK?
* Turbo headers will be equal length
I think my biggest concern is how this combo will work together. The cam selection is also not my forte, so please speak up if you have better options
I appreciate your time, and feedback!
Rick Johnston
Cedar Ridge, CA
I have been cruzing this forum and thesamba for awhile in preparation for building an engine for a 1966 Porsche 912 my uncle gave me to restore. The 912 was parked in his backyard for many years and had a tree growing over the top of it when I first saw it. I asked him about it and he offered it to me to restore. I plan to start this summer as my Factory Five project will be complete.
I have built several Ford Windsor motors, but this is my first foray into the VW world. I think I'm at a place now where I have figured out the differences between the dizzying array of motor types, body types, cooling options and have been preparing a type4 build list. The 912 has no motor in it to rebuild and after looking at the different options I settled on the type 4 for a few reasons.
* Real Porsche engines are prohibitively expensive to build
* The 1976 912 had a 912 E model that actually used a 2.0L type 4 engine, so I know it fits
* The type4 bolts right up to the existing transaxle
* The type4's bottom end is supposedly bullet proof
* Going to a larger displacement appears to be relatively well supported
* From an originality perspective, the T4 isn't too far out of line considering the 912E
I picked up what appears to be a 1.8L type 4 from a friend for a very reasonable price. I have not removed the heads or split the case yet to see if it is actually a 1.8, or what changes may have already been made in the past.
I have also never built a turbo motor before, and I would really like to give this a shot. I have experience using Megasquirt ECU’s, and used a highly modified version to build the Ford 306 ITB motor that I used for my FactoryFive AC Cobra replica. I also converted my wifes 1969 Camaro to EFI using megasquirt.
Looking over the engine kit manufactures it looks like I can purchase a kit to bring the 1.8L to 2257cc without extra machining. Also, I am not sure the turbo would play as nice with a stroke longer than 78mm, and I really don’t think I need a bigger bore because the HP/torque should be way more than enough for me. I considered keeping it at 1800cc, but I could not find any forged piston 1.8L kits.
I was hoping that the more versed members in this forum might be able to look over my build plan and make sure that I have not missed anything, and that my plan is sound. I am definitely open to suggestions! My goal is to build a turbo motor that will see street use only. I want it to be reliable, but fun to drive. I know I will need to upgrade the gear set in the 601 transaxle as well to accommodate the new motor. I have only done enough research in this area to know that it can be done and that the parts are available.
So, here is my initial build list:
* 1.8L engine case
* Engine cleaned, and bore align checked (European Motorworks? HAM?)
* 2257cc forged engine kit from AA Pistons (Part#: EK 004 2257 JE) (cast iron not biral cylinders?) 96mm bore x 78mm stroke with forged JE pistons
* Dynamic balancing performed by AA Pistons – in addition to kit package
* Scat 20088 (c45 grind .507 lift, 298, 262 duration) cam – or Webcam 119
* Solid lifters (Scat or WebCam)
* Heads – Assuming the 1.8L heads I have can be rebuilt (by European Motorworks? HAM?):
** Larger valves – 36mm x 48mm? (need advice here!)
** Dual springs
** New valve guides
** Full port & polish
** 3 angle valve job
** Swivel valve adjuster kit (EMPI 4061)
** Solid rocker arm spacers to replace spring tensioner
Turbo’s I am considering (I plan to run 15PSI max):
* T28 (AKA “disco potato”) - sr20det
* TD05H – from Mitsubishi EVO9
* T04B – twinscroll option available and oil cooled only (my first choice ATM)
* GT3076R
As I mentioned above, I am a turbo novice so any recommendations here would be most helpful!
Notes:
* Max RPM 6500ish is plenty for me…I really don’t know how the type 4 revs?
* My research shows that a 914 flywheel, clutch and clutch plate should bolt right up?
* I will need to fabricate a motor mount
* I will fabricate my own exhaust and intake plumbing
* What compression ratio should I strive for? VW engines in general seem to run much lower compression ratios than I am used to on Ford V8’s?
* I will be running a DubShop hidden crank wheel for the crank VSS
* I will be running a DubShop mini cam sync for the cam VSS
* I will be running an intercooler
* Original pancake style cooling (more room for turbo plumbing and intercooler) I will need to do some fabrication here.
* Is the standard oil pump OK?
* Turbo headers will be equal length
I think my biggest concern is how this combo will work together. The cam selection is also not my forte, so please speak up if you have better options
I appreciate your time, and feedback!
Rick Johnston
Cedar Ridge, CA