Alternate history: M96 Cup engine
Discussion
Well, the (annoying) answer to that is that it depends.
The core of these engines is (literally) a Hartech large capacity conversion, so as long as we hit our target for character (pulling hard to 8,500rpm, very low inertia, very rewarding to rev it out and so on) then I'd consider it a success if we don't *lose* any power over what the standard Hartech high-capacity engines produce.
Of course I'd hope that all the work we are doing leads to more power - and I do of course have some ideas of what that *could* be, based on the flow-bench, the cam profiles and the modelling that we have done. But the situation that we are in is that as long as we don't lose any power from that which the Hartech units produce we're already at a figure that pushes a 996/997 (or a Boxster, or a Cayman) down the road very effectively.
All of this is a long-winded way of saying that I'm not going to give a hostage to fortune by specifying an output - lets see what the engine dyno says.
Also I'm perfectly serious when I say that character of delivery is ultimately more important than what is delivered.
The other thing we're doing is engineering out the issues that Porsche left in the M96, so the goal is to end up with reliability, character and power.
The core of these engines is (literally) a Hartech large capacity conversion, so as long as we hit our target for character (pulling hard to 8,500rpm, very low inertia, very rewarding to rev it out and so on) then I'd consider it a success if we don't *lose* any power over what the standard Hartech high-capacity engines produce.
Of course I'd hope that all the work we are doing leads to more power - and I do of course have some ideas of what that *could* be, based on the flow-bench, the cam profiles and the modelling that we have done. But the situation that we are in is that as long as we don't lose any power from that which the Hartech units produce we're already at a figure that pushes a 996/997 (or a Boxster, or a Cayman) down the road very effectively.
All of this is a long-winded way of saying that I'm not going to give a hostage to fortune by specifying an output - lets see what the engine dyno says.
Also I'm perfectly serious when I say that character of delivery is ultimately more important than what is delivered.
The other thing we're doing is engineering out the issues that Porsche left in the M96, so the goal is to end up with reliability, character and power.
Hi Dammit - super interesting threat and well beyong my technical/ mechanical understanding.
I have an engine that was rebuilt with latest IMS bearing, better cams and flowed head amongts other things. It produced about 340bhp on the dyno before being run in so i think some real gain over stock. it really comes alive above 5000rpm where it feels a lot livelier than before.
Although i need to get the brakes to a place i am happy with first, i was wondering if there are any bolt-on engine mods that you think could add some power? induction or exhaust (i have 200 cell cats but standard manifolds)
I have an engine that was rebuilt with latest IMS bearing, better cams and flowed head amongts other things. It produced about 340bhp on the dyno before being run in so i think some real gain over stock. it really comes alive above 5000rpm where it feels a lot livelier than before.
Although i need to get the brakes to a place i am happy with first, i was wondering if there are any bolt-on engine mods that you think could add some power? induction or exhaust (i have 200 cell cats but standard manifolds)
Dammit said:
shalmaneser said:
What's the plan with the itbs? I'd love to fit those to my boggo m96 3.4 in time, if only for the noise!
We initially looked at re-purposing some ITB's from an M3 with an adapter plate, but whilst it looked good (and would have sounded great I'm sure) the flow-bench showed that the adapter plate was killing flow. Given the not insignificant work that has gone into raising flow (both in terms of volume and velocity) of the heads themselves it would be lunacy to then write-off these gains with ITB's that were not optimised.We started discussions with a UK company that makes custom ITB's who is based close to Martin and went through a discussion that led to a CAD model, once that was signed off we went for a rough 3D print, then a higher resolution one which went to the flow-bench, and once that was signed off we ok'd the final design.
I would warn - these are designed for our application, and whilst they can of course be bolted to a stock 3.4 (or indeed 3.6) the question of whether they'd give gains on a stock engine is one that we have not looked at answering. They'd sound excellent, of course.
The main issues with an ITB conversion is that the M96 has negative crankcase pressure so needs a fair amount of vacuum which can be tricky with ITB's as I understand. The mapping is clearly also an issue but there are various ways around that such as aftermarket management or a piggy back system.
Excited to see this motor come together!
Agree with the others that this is a very interesting project and I believe your goals are right on target.
Does Baz have any interest in offering a rebuilt based on learnings from this project ( Ie higher capacity with more character and top end. ) Or is this going to be a one(Or two) off.
Does Baz have any interest in offering a rebuilt based on learnings from this project ( Ie higher capacity with more character and top end. ) Or is this going to be a one(Or two) off.
I think it’s far too soon to even think about that - we don’t know whether these engines are going to perform as hoped yet- total* humiliation may still be a couple of Dyno pulls away.
If the engines don’t turn into 250kg of high speed confetti then we still have to prove that they work in the cars, will handle a trundle to the Alps and then set your trousers on fire through the mountain passes- so much still to do before that sort of question could even be asked.
/*Expensive humiliation at that
If the engines don’t turn into 250kg of high speed confetti then we still have to prove that they work in the cars, will handle a trundle to the Alps and then set your trousers on fire through the mountain passes- so much still to do before that sort of question could even be asked.
/*Expensive humiliation at that
Edited by Dammit on Thursday 21st January 14:41
james.a.c.911 said:
Hi Dammit - super interesting threat and well beyong my technical/ mechanical understanding.
I have an engine that was rebuilt with latest IMS bearing, better cams and flowed head amongts other things. It produced about 340bhp on the dyno before being run in so i think some real gain over stock. it really comes alive above 5000rpm where it feels a lot livelier than before.
Although i need to get the brakes to a place i am happy with first, i was wondering if there are any bolt-on engine mods that you think could add some power? induction or exhaust (i have 200 cell cats but standard manifolds)
Based on conversations with Wayne at Chip Wizards who has tuned a lot of these engines in different configurations a lot of modifications (especially to the intake side) end up costing you power - not a huge amount, but Porsche designed the whole system to work together in a highly integrated fashion, so a change that makes sense on examination of the individual part may upset the balance of the system, if that makes sense?I have an engine that was rebuilt with latest IMS bearing, better cams and flowed head amongts other things. It produced about 340bhp on the dyno before being run in so i think some real gain over stock. it really comes alive above 5000rpm where it feels a lot livelier than before.
Although i need to get the brakes to a place i am happy with first, i was wondering if there are any bolt-on engine mods that you think could add some power? induction or exhaust (i have 200 cell cats but standard manifolds)
We're checking everything on the flow-bench, so we know whether it's a step forward, a step backward or no change - but we're not doing that with a largely stock engine, so I'm afraid I can't recommend anything to you.
I also have the 200 cell X-pipe on my stock engine and I will say it *sounds* great, so I don't care if it's costing me 10bhp. Hopefully it's giving me 10bhp, but we've not examined that, so we don't know.
I’m running 200 cell X-pipe cats (with switchable sports back boxes) and I’m pretty certain that it has lost something in the mid range. Maybe a tiny gain up top. Despite this I love that it sounds silly when I want it to (and quiet when I don’t) so can’t bring myself to swap back to standard cats. I have been considering taking it to Chip Wizards but wasn’t sure whether it’d be a waste and/or Wayne would just tell me I’m an idiot for fitting those cats 
A question for those who might be reading this with a lot more ECU knowledge than I have - the thinking was to use Syvecs, but I am unsure what model would be best, and I admit I don't understand the difference between Life Racing and Syvecs and why one would choose one over the other?
When considering an ecu, you need to think about what features you want. Drive by wire, single wideband or one for each bank, how many inputs you want to add (oil pressure, oil temperature, etc), what outputs you want to control (a/c compressor, tach signal, electric water pump, exhaust valves, etc). Then you need to think about canbus support
Ideally make a list and see what suits your needs best. No point buying something expensive with features you won't use.
The other consideration is who is going to be wiring it up and tuning it. Most tuners will tune anything but some stick to what they know.
With regards to the M96 Cup engine build, have you thought about ditching the mechanical water pump for an electric one?
Ideally make a list and see what suits your needs best. No point buying something expensive with features you won't use.
The other consideration is who is going to be wiring it up and tuning it. Most tuners will tune anything but some stick to what they know.
With regards to the M96 Cup engine build, have you thought about ditching the mechanical water pump for an electric one?
Dammit - I assume, because I know how thorough you all are, you've already seen this?
https://verbotenmotorsport.myshopwired.co.uk/scave...
https://verbotenmotorsport.myshopwired.co.uk/scave...
I'm afraid you give me too much credit - I wasn't aware of this product until I saw your post. Very interesting!
It's reassuring that we're not the only people who believe that this is a key vulnerability/required fix for the M96 (as well as Porsche I suppose, but of course they don't make the dual-stage pumps anymore).
It's reassuring that we're not the only people who believe that this is a key vulnerability/required fix for the M96 (as well as Porsche I suppose, but of course they don't make the dual-stage pumps anymore).
We have been running engine simulations recently - something we've done quite a lot of over the course of this project as we can't afford to make 10 intakes, 10 exhausts, then run every combination on the engine Dyno to see what works best.
This one is the final sim that we've used to specify exhaust manifold primary lengths and internal diameter, these are now being made by a very pleasant chap in Silverstone.
Also, because if you looked up "feature creep" in the dictionary it would reference our engine project, we're making a complete exhaust now (this was never the original plan), we always intended on making a true equal length manifold, but given the (surprisingly large) diameter that we need for the primaries and what that then meant for where the flange had to be, we've had no choice but to do as a minimum manifold and cats, so we thought we may as well go the whole hog.
This one is the final sim that we've used to specify exhaust manifold primary lengths and internal diameter, these are now being made by a very pleasant chap in Silverstone.
Also, because if you looked up "feature creep" in the dictionary it would reference our engine project, we're making a complete exhaust now (this was never the original plan), we always intended on making a true equal length manifold, but given the (surprisingly large) diameter that we need for the primaries and what that then meant for where the flange had to be, we've had no choice but to do as a minimum manifold and cats, so we thought we may as well go the whole hog.
Dammit said:
We have been running engine simulations recently - something we've done quite a lot of over the course of this project as we can't afford to make 10 intakes, 10 exhausts, then run every combination on the engine Dyno to see what works best.
This one is the final sim that we've used to specify exhaust manifold primary lengths and internal diameter, these are now being made by a very pleasant chap in Silverstone.
Also, because if you looked up "feature creep" in the dictionary it would reference our engine project, we're making a complete exhaust now (this was never the original plan), we always intended on making a true equal length manifold, but given the (surprisingly large) diameter that we need for the primaries and what that then meant for where the flange had to be, we've had no choice but to do as a minimum manifold and cats, so we thought we may as well go the whole hog.
I mean, you should definitely try to monetise some of the development you've put into this. I would love to see some cool upgrades for the 996.This one is the final sim that we've used to specify exhaust manifold primary lengths and internal diameter, these are now being made by a very pleasant chap in Silverstone.
Also, because if you looked up "feature creep" in the dictionary it would reference our engine project, we're making a complete exhaust now (this was never the original plan), we always intended on making a true equal length manifold, but given the (surprisingly large) diameter that we need for the primaries and what that then meant for where the flange had to be, we've had no choice but to do as a minimum manifold and cats, so we thought we may as well go the whole hog.
Bottom end is going together - an exciting moment (for me, anyway!):
We've been doing a lot of thinking about the exhaust system, what's absolutely certain is that we need to make our own manifolds as nothing available off the peg is going to match our requirements.
One possible route forward would be to use an OTP GT3 cat section and silencers with our manifolds, as the diameter of those should work. More thinking to be done.
We've been doing a lot of thinking about the exhaust system, what's absolutely certain is that we need to make our own manifolds as nothing available off the peg is going to match our requirements.
One possible route forward would be to use an OTP GT3 cat section and silencers with our manifolds, as the diameter of those should work. More thinking to be done.
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