The realities, do's and dont's of boosting a 1985 928 5SPD
#16
Rennlist Member
Exactly... the early 32v in fact can accept 5-6lb of boost without any real modifications of the ignition timing.
The reason is that Porsche gave the 84-86 cars very safe timing to take account of the variability of fuel available at that time. It is this margin which has been exploited by Ken (US 32v 85/86) and also by me (84-86 16v Euro) and this unlocks quite a bit of extra power for those (unboosted) engines.
I don't know how much boost Charles intends to give his engine, but if going above 6psi I would say a knock control system such as the Vampire is an essential.
The reason is that Porsche gave the 84-86 cars very safe timing to take account of the variability of fuel available at that time. It is this margin which has been exploited by Ken (US 32v 85/86) and also by me (84-86 16v Euro) and this unlocks quite a bit of extra power for those (unboosted) engines.
I don't know how much boost Charles intends to give his engine, but if going above 6psi I would say a knock control system such as the Vampire is an essential.
#17
Burning Brakes
Thread Starter
Exactly... the early 32v in fact can accept 5-6lb of boost without any real modifications of the ignition timing.
The reason is that Porsche gave the 84-86 cars very safe timing to take account of the variability of fuel available at that time. It is this margin which has been exploited by Ken (US 32v 85/86) and also by me (84-86 16v Euro) and this unlocks quite a bit of extra power for those (unboosted) engines.
I don't know how much boost Charles intends to give his engine, but if going above 6psi I would say a knock control system such as the Vampire is an essential.
The reason is that Porsche gave the 84-86 cars very safe timing to take account of the variability of fuel available at that time. It is this margin which has been exploited by Ken (US 32v 85/86) and also by me (84-86 16v Euro) and this unlocks quite a bit of extra power for those (unboosted) engines.
I don't know how much boost Charles intends to give his engine, but if going above 6psi I would say a knock control system such as the Vampire is an essential.
I'm shooting for 10 eventually, but I'm starting low at 5-7 range. Is this vampire you speak of ? http://www.jandssafeguard.com/VampirePage/Vampire.html If I go the vampire route would I still need your ST kit?
Last edited by cpayne; 03-17-2017 at 10:00 AM.
#18
Rennlist Member
Yes, that's the system. There's a couple of people here who have used it, for example Andrew Olson on his twin screw 85/86 car.
That system would be your safety net. I can provide you with a EZ-F starter chip designed to suit 10psi. That combined with the Vampire would keep you out of big trouble, but to fine tune the system you would need a Sharktuner.
I was ill for a week so have been catching up working on the pile of boxes in my office. I haven't forgotten your enquiry.
That system would be your safety net. I can provide you with a EZ-F starter chip designed to suit 10psi. That combined with the Vampire would keep you out of big trouble, but to fine tune the system you would need a Sharktuner.
I was ill for a week so have been catching up working on the pile of boxes in my office. I haven't forgotten your enquiry.
#19
Administrator - "Tyson"
Lifetime Rennlist
Member
Lifetime Rennlist
Member
I have a 2.5 bar MAP sensor installed in my EZF which will allow me to tune the ignition curve based on actual boost, not just RPM and MAF load.
This isn't necessary, just something we wanted to play with since the 85/86 US and 84/85 EuroS ignition brains have MAP sensors.
Unfortunately the car was parked just as I was getting this setup tuned and as life goes on, I haven't picked it back up yet.
This isn't necessary, just something we wanted to play with since the 85/86 US and 84/85 EuroS ignition brains have MAP sensors.
Unfortunately the car was parked just as I was getting this setup tuned and as life goes on, I haven't picked it back up yet.
#20
Burning Brakes
Thread Starter
Yes, that's the system. There's a couple of people here who have used it, for example Andrew Olson on his twin screw 85/86 car.
That system would be your safety net. I can provide you with a EZ-F starter chip designed to suit 10psi. That combined with the Vampire would keep you out of big trouble, but to fine tune the system you would need a Sharktuner.
I was ill for a week so have been catching up working on the pile of boxes in my office. I haven't forgotten your inquiry.
That system would be your safety net. I can provide you with a EZ-F starter chip designed to suit 10psi. That combined with the Vampire would keep you out of big trouble, but to fine tune the system you would need a Sharktuner.
I was ill for a week so have been catching up working on the pile of boxes in my office. I haven't forgotten your inquiry.
#22
Burning Brakes
Thread Starter
Google drive link to the Turbo design and MAF harness documents in post 1 for those who have expressed interest.
https://drive.google.com/open?id=0B-...zJZbFVMWVZoLXc
https://drive.google.com/open?id=0B-...zJZbFVMWVZoLXc
#23
Burning Brakes
Thread Starter
Installed the new scavenge pump today and started cleaning up some from the electrical . The aluminum pump mount plate was a nice attempt, but had burrs on it. Filed the burrs off . It was mounted to a hole drilled in the chassis with a hardened steel bolt and no nut. Vibration over time would surly bugger the aluminum threads in the bracket mount point. To mitigate this risk we put a nylock on the bolt to hold the mount in place, so if the aluminum threads do degrade the unit will stay on the car.
Apples to Oranges when comparing the replacement pump I bought versus the one supplied with the turbo.
Old pumps wiring.
New pumps wiring.
This is how I found the wiring in the battery box. Notice the Red wire from the old pump and the White wire (not sure what that one is for yet) with electrical tape to aide in resisting damage from where they enter.
Added some Gold plated terminals. I Have some more zip tying to do and will mount the relay in the battery box. Added grommet for the new pumps wiring. I'll be rerouting the white wire back through the grommets to avoid the battery box lid from resting on it.
Drilled a small hole for the white wire and put rubber grommet on it fed it out the grommet and back into the battery box grommet I put in yesterday. tidied the wiring up a bit more. Is there a battery brace part number? as the PO used 2 2x4s to keep the battery from moving around.
Apples to Oranges when comparing the replacement pump I bought versus the one supplied with the turbo.
Old pumps wiring.
New pumps wiring.
This is how I found the wiring in the battery box. Notice the Red wire from the old pump and the White wire (not sure what that one is for yet) with electrical tape to aide in resisting damage from where they enter.
Added some Gold plated terminals. I Have some more zip tying to do and will mount the relay in the battery box. Added grommet for the new pumps wiring. I'll be rerouting the white wire back through the grommets to avoid the battery box lid from resting on it.
Drilled a small hole for the white wire and put rubber grommet on it fed it out the grommet and back into the battery box grommet I put in yesterday. tidied the wiring up a bit more. Is there a battery brace part number? as the PO used 2 2x4s to keep the battery from moving around.
Last edited by cpayne; 04-04-2017 at 11:17 PM.
#24
Burning Brakes
Thread Starter
Scavenge pump comparison.
Original pump less than 25 miles from since I got the car home. Probably 100 miles total. Listen for the annoying whining of the original scavenge pump.
New pump
Original pump less than 25 miles from since I got the car home. Probably 100 miles total. Listen for the annoying whining of the original scavenge pump.
New pump
Last edited by cpayne; 04-04-2017 at 11:20 PM.
#26
Burning Brakes
Thread Starter
I'm moving the MAF back to the its original spot and putting in the chipset later this week. I'm waiting on an 87 FPR as it is supposed to push the necessary fuel for 30LB injectors.
I'm also on the hunt for an appropriate inter cooler. I reached out to Mr. Kuhn to see if his rig would work with my single turbo.
#27
Rennlist Member
In reading the online manual for the Vampire, looks like you can use a two coil feed setting/input and then set the box to retard all 8 ( by affecting both coils ) once knock is detected.
A bit pricey, but would be easy to go back to stock, works with N2O too
Dave