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Has anyone converted their N/A 964 to EFI? Any thoughts on the best system, things to beware of, estimated costs to do it right? I have had my motor completely rebuilt and is now a 4.0 with all the right parts, but I hate thinking that I am trusting a modified "chip" to maintain a safe environment with all the changes to the pistons, heads, cams, intake, exhaust, fuel pumps, throttle body, injectors etc...
Just curious who built/consulted you on a 4.0 without discussing engine management with you? That's a huge piece of the equation they left out.
Motec seems to be the gold standard on 964 builds, although there are better systems out there now. Motec is just he most common.
Talk to a reputable shop about their recommendations for your setup/goals.
911's have had EFI since 1984. 930's and 965's still had CIS until the 965 turbo 3.6. You can install a motec or similar unit to have better control, but this should have been a question before you spent big $$'s on such a serious/awesome sounding engine build. I say that because going standalone engine management like motec would have allowed ITB's and/or more aggressive cams. However, with careful dyno/afr tuning a custom chip will work fine and be safe
Just curious who built/consulted you on a 4.0 without discussing engine management with you? That's a huge piece of the equation they left out.
Motec seems to be the gold standard on 964 builds, although there are better systems out there now. Motec is just he most common.
Talk to a reputable shop about their recommendations for your setup/goals.
I should have been more forthcoming. So the engine was built by Gordon Friedman at AutoMetrics in South Carolina. Pretty reputable guy/shop. And yes we did discuss my goals etc. Being this is not a track car and I was not asking for the absolute highest output possible (just reliable power with a great usable torque curve for our mountain roads) the thought was we did not need a full system. He has certainly tuned the car with conservative AF ratio's etc. Its me that is second guessing myself. I am coming from a highly modified 965 where, in my opinion, full flexible EFI system is needed. My project car is way over the estimated time to complete and I may just be a victim of too much time to think and nothing fun to drive.
I'd agree with you that a hopped up 965 needs fully programmable EFI. IN this case though I am not so sure. I've installed and tuned a number of Motecs Haltechs and tuning a track car is one thing,
tuning a "daily driver" is quite another. Porsche has probably 1000+ man hours into mapping and
that's tough and expensive to duplicate. I don't know what's been done tuning wise but if it's been conservative I'm not sure I'd go a lot further. The hot wire AFM does a damn good job measuring
and as long as knock sensors are still online I kinda doubt you'll be much if any better off spending
tons on a new system.
I have installed the UK sourced Specialist Components Kit on my C4. The kit includes a new ECU, MAP sensor (to replace the barn door), new 440cc injectors (give headroom for more power) and Carbon Fiber intake pipe with foam filter.
My only criticism of the system is that it was touted by some as plug and play, but it's more of an engineer developed kit for capable mechanics to allow tailoring of the engine management system to suit builds outside the factory norms.
I've used the base map supplied, and it started first time, however I had to solve idle stalls myself. I was expecting that as I have a LWF but I didn't expect to have to find the solution by asking others which parameters to change.
I recently decided to fit a wide band sensor and do an auto map, just to make it more suited to my exact situation with fuel type etc. Basically I set the Lambda parameters I want, then drive the car through the full range and use the learned values to alter the base map. A cheap alternative to a dyno mapping exercise.
The system seems very user definable which is great if you know what you are doing. It's less useful for the DIY mechanic with a stock 964 and basic understanding of engine tuning.
My car is running on VEMS. I used the kit from peep, but it was far from a finished plug-n-play product. Also, no product support what-so-ever. Still tweaking things here and there, idle is a PITA. Other than that, the car runs really well and auto-tune is a nice feature. Seems like my setup is very similar to John's from above, except that I removed the distributor and am running two banks of coil-packs.
[QUOTE=John McM;13223016]I have installed the UK sourced Specialist Components Kit on my C4. The kit includes a new ECU, MAP sensor (to replace the barn door), new 440cc injectors (give headroom for more power) and Carbon Fiber intake pipe with foam filter.
On my 965 which was modified i used a Haltec system which was very reliable and gave great performance.
But again it all depends on who tunes it which is everything.
I have installed the UK sourced Specialist Components Kit on my C4. The kit includes a new ECU, MAP sensor (to replace the barn door), new 440cc injectors (give headroom for more power) and Carbon Fiber intake pipe with foam filter.
Old thread although I agree with Elliot I am also using the Haltech 2500 elite. It isn't Motec but does everything I need at considerably less cost. I also have access to the most import part the talent to tune these for maximum power and reliability. I have seen these guys take some very nicely built engines done by the most reputable shops and get more out of them with increased reliability.
04-19-2016, 06:13 PM
EFI for N/A 964
