12V V6 on aftermarket ECU

[CorseChris]

Here's the power run...

The motor has 9.5:1 pistons (which I thought was S spec, but when I looked at the CarDisc the other day it said 10:1 was S spec). Cams are C&B 'mild road'. Everything is new, valve clearances checked and adjusted as needed a few days before the RR session when I did the first service/head re-torque etc. Valves are new & standard, but I did have a 3 angle valve & seat job done. Inlet is standard, although I did do some gentle port matching to remove some nasty steps. Exhaust headers are standard cast, rest of system is same bore pipework into a fairly small 'silencer' box and then out in the same size tubes again. I think (but don't know for sure) that the silencer is just a simple perforated pipe, so shouldn't be restrictive....but might be I guess. I did a cold & dry cranking compression check while doing the service and it gave 15 bar/220psi. Cam timing was absolutely spot-on. I bypassed the throttle body water jacket to reduce charge heating and use an oil vapour catch tank to avoid octane reduction from oil fume.

It didn't run that smoothly on the Motronic and had a habit of pinking (pinging) unless I ran it on 97RON AND fitted the 'red' plug. This did make me suspect cam/crank timing at first but I double-checked that.

I guess it is what it is, and that's that. As I say, absolute power accuracy isn't in any way guaranteed with a RR, but I think it's close.

It would have made 200 on 97RON and a couple more degrees timing no doubt, but that's just fiddling the numbers!

I recall being dissapointed some years back when getting a Rover V8 mapped. It was a 4.2 with a mild cam and CR lift and it only made 226bhp/250ftlb. Makes the Alfa 3.0 look pretty good.

Interestingly, both the Rover V8 and Alfa V6 12V respond really well to boost. We'll see how mine does.

[junglejustice]

Well, since you're planning on "blowing" this thing, its probably a good thing - 9.5:1 is a good starting point for static CR and blower!

[CorseChris]

I was always hedging my bets on this motor...I wanted a basically good aspirated setup that I'd be happy with should the supercharging not work out for some reason. I'm aiming for about 8psi of boost with air/water charge cooling. Depends how it goes. I figured a short overlap cam was the thing so went for the mild C&B cam and had originally intended on stock CR, but was told by the supplier that they only had the 9.5 pistons in stock, which they told me was slightly higher CR than normal..and I believed them.

CarDisk shows the 91-93 car as 9.5:1, 183bhp, 191ftlb, the S as 10:1, 200bhp and 195ftlb. I'll take these as accurate as they are the shop manual of course. 198bhp and 208ftlb on stock CR doesn't sound so bad now. The C&B mild cam is very similar to the S cam spec I think.

Greg was edging me toward a much lower CR and more boost, which would yield more power ultimately of course, but it wouldn't give me an easy route back to aspirated if I didn't like it or it doesn't work. You might wonder what's not to like about more power and torque...but it's the potential for noise and problems with the installation that might make the choice. Hope not, but I didn't want to end up down a dead-end. Maybe a mistake, but that's the way I chose to do it.

Anyhoo, as you say, a good place to start for some mild forced induction. Plenty of capacity in the injectors I used 360cc/min @ 3 bar. I might look at a twin injector setup as we had trouble getting the injection rate low enough at idle - had to run it slightly richer than ideal to stop the injectors shutting off. There might be some useful gains in cooling to be had from injecting some fuel into the plenum perhaps, then reverting to just stock injectors in the inlet runners for lower demand areas. As long as this is done at higher revs/loads it should be OK I think. I could probably get away with 3 or 4 of the bigger injectors rather than using all 6. Mm, time for some sums I think. 3 would be easier to install than 6.

A friend over here is using 2 sets of injectors on his V6 with bike TBs that have 220cc injectors. It's set up to use the stock injectors until they reach about 85% then it switches over to both sets. Works really well.

[slyalfa]

That is very close to what EA (software sim) shows for a S spec (If I entered all the stuff right?)
I did this a long time ago.

[CorseChris]

Interesting. Looks a lot like the S numbers from the data, but it suggests a higher revs for max power figure than is seen in real life...but close none the less. That extra half point on the CR makes all the difference doesn't it.

[CorseChris]

It's been a while...but I've been slowly moving this along. The fabrication of all the main parts is now complete, I just need to fit the air/water charge cooler pre-rad, header and pump etc, then off we go. I've also decided to go for water/methanol injection as I've been getting concerned (paranoid) about detonation on the relatively high (for supercharged) CR I'm using.

I'm using a bike TB for the blower bypass valve for a number of reasons, not least being that the OEM bit wouldn't fit in my car!

More pertinent to the orignal thread, I converted from batch to sequential injection a while ago. I wasn't happy with the control at very low demand (due to the big injectors) so going sequential was a zero-cost thing to try. I just had to add a few wires and a cam-angle sensor. I modified the base of the original distributor (which I had previously removed as it's running wasted spark) to take a crank trigger from a Lancia Thema Turbo and this is working well. I probably should have wired it up like this the first time round, don't really know why I didn't. Overall, this has made a big improvement to fuel control at light loads and I've been running for a while now with a large chunk of the map set to lean AFR and the ECU working adaptive, so it's gradually tuning itself in as I drive. On a run in the countyside the other week I got 27.7 mpg (imperial) which isn't too bad I reckon. Of course, all this will go out the window once the blower is on....but it keeps me amused...

More anon once I've got all the bits bolted on. I intend doing a 'boost' check by running it up off-load to see just what it produces. Fuel-wise I'll put a simple +50% @ 7psi into the MAP table.

[CorseChris]

Finally some shots of the bits....on the carpet, not the car though

Inlet is part of the Ford SuperCoupe casting with part of a 164 plenum grafted on, The throttle body goes here, with the IACV attached to the side and working in the normal way. Outlet is part of the Ford with some 2 3/4" pipe, plus the elbow is where the bypass valve fits. This connects back to the short stub of 2" pipe on the inlet 'lump'. I'm using a 40mm bike TB as the bypass valve. I don't think it's apparent on these shots, but the outlet casting has '3.8' script cast into it for the Ford it came from - I tweaked this to read 3.0 Sad, ain't I!

Cooler is the core of a Jaguar XK cooler grafted into a cut-down 164 plenum.

It's all the size & shape it is in order to fit in the Stratos rep.

With hindsight, an in-line cooler would probably have been better.....

Having had a critical look at it, and following advice, I'm now going to do per-port water injection as this is the only way I can see to get even feed to each cylinder without risking problems of it wetting out in the cooler etc. Another good reason to go for an in-line cooler and retain a stock plenum.

[Greg Gordon]

I like that intercooler design. It's very clever, and space efficient. I think it will offer good cooling and a low pressure drop. I can't understand exactly where you are putting the throttle and or bypass valve(s) but with more pictures it will probably become clear.

[CorseChris]

Hi Greg,

The first picture shows the blower inlet 'stub'. This adapts the old Ford OEM inlet casting that mates to the blower inelt with the 164 TB, so my throttle plate is pre-blower.

I'll do some more pictures once the whole thing is assembled. Some of those shots do look a bit 'objet d'art' don't they! Or perhaps familiar objects from unfamiliar angles

I understand that the core I've used works well on the Jaguar, so figured the demands of half a 4l motor running more boost than I intend would be similar to an entire 3l

[Greg Gordon]

It all makes sense now! I am glad you are putting the throttle pre-blower. That eliminates the need for a second bypass valve, and with this project it doesn't really add any complexity. The crinkle finish powder coating looks great.

Looking to see what some factory engineers did, as you did with this intercooler is almost always a good starting point. They have a large budget and a lot of brainpower to throw at these problems. I always look to see what they did. In this case I think your intercooler solution is brilliant. Not too expensive, very effective and most importantly it fits.

It's funny you call this a "tribute car" I think with a supercharged Alfa V6 in there, the original street versions of the Statos will be paying tribute to your tail lights.

Greg

[CorseChris]

....some of the parts assembled onto the car now.....

I've put some tape over where the TB fits so it's hard to make out.

There is a 90 elbow that goes from the end of the blower output pipe to the inlet of the charge cooler/plenum. Still on the stock plenum at the moment. next step is to couple up the drive belt, make sure that's straight & true, then see how much boost it gives.

Out of curiosity, I connected the bypass valve vacuum line to the engine and fired it up. Quite surprised (but pleased) at how long it stays in bypass - I think this is going to give a really smooth transition on/off boost.


....getting closer......

[Greg Gordon]

I like it, although I am not too crazy about blue hoses with white lettering on a green car. I would have preferred black, silver, or green hoses.

Greg

[ToonRboy]

Are those just bolts going into the valve cover holding the blower on there? If so, I doubt it'll hold. The packaging is quite good. Hat's off for the fabbing "outside-of-the-box". Obviously a challenge given the space constraints. I can see the fins of the intercooler through the ports on the plenum - what's the cooling medium?

I think a big turbo installed down low would have been a wiser choice. On vehicles in this configuration, you have a lot of open space under there beneath the "bonnet" in the rear. 'Course that would entail an elaborate custom exhaust (6 into 1 or dually if you wanted). One thing for sure the top of the engine would be much cleaner and accessible. You'd have to find space for an intercooler as well (Thunderbird SC, or Buick GN?). But definitely do-able given the skill displayed.

Cool car & BTW, nice torque curve. You could drive that thing half-way 'round the world and never come across another!

[CorseChris]

Greg, When I built it, black was an extra cost, long delay option only available on selected sizes...and I'm impatient!! Now of course, I've found a supplier that's local, cheaper, and carries stock of most colours. I've chosen black for all the pipe work associated with the cooler circuit at least! Sadly, the lettering seems obligatory regardless of supplier - they never miss a marketing oportunity and the darn stuff won't come off. I don't much care for the bright blue myself either TBH, but it does the job.

ToonRboy, the valve cover is made from billet and is 25mm thick, relieved as needed to clear the valvegear etc. That's not obvious from these shots though. You can just make out the edge on the first of the 3 shots. The blower fixings are M10 thread inserts that go 20mm into the billet so I'm pretty happy they will hold...time will tell though! Turbo - well, it's been done with one of these. A friend had the same car with a twin-turbo setup that worked very well, but he went through many, many problems to get it working right. He had to sacrifice quite a large chunk of space from the trunk area for the rear turbo, and the front one was a real mare to get at! Certainly, a single turbo setup would be a better option for packaging than the twin. I don't really know why...but I never wanted to go turbo on this car, plus, I've always had a hankering to play with a blower - again, can't really say why that is!

The cooler core is from a supercharged Jaguar. I've still to add the pre-rad, pump, header tank and associated plumbing, plus the water injection kit...so it's getting pretty full in there.

No doubting that I've made the thing quite hard to work on now though. Changing the plugs on the front bank means removing the blower and everything connected to it. Far from ideal, but there simply wasn't anywhere else it could go without doing serious chassis mods or removing the A/C compressor. That's something I'll not do - this is a road car (so I want it reasonably comfortable), and even a hint of sunshine turns it onto a sweatbox without the A/C. The oil filler had to go as well - I'll use the cover over the oil pump drive for top-ups.

Space-wise under the 'hood' isn't as good as it might seem from these shots. The upper limit of usable volume (assuming you don't want to see out the back) is defined by that diagonal chassis brace + 2" more or less. There is about 2" above the level of the plenum at the back. As it is, I can still see OK in the rear view mirror, although the blower outlet has taken a chunk out of it.

The other brand of this kit has a flat deck built in to the rear cover (as per the original car) so the upper limit is top of plenum + roughly 3" all the way from front to back and left to right.


Unlike many of the Hot Rods you guys have over there, that have a fantastic clean look under the hood....whenever I open this up I usually think....strewth...how much crap have I squeezed in there.....

[Greg Gordon]

That valve cover mounting system is pretty unique. I never thought of that. Once it's all dialed in I think it will work well, and the hassle involved with a spark plug change won't occur too often. Hopefully you won't have many initial problems. Initially go with spark plugs one heat range colder than stock.

Historically Lanica (and Fiat) rally cars have been supercharged. The only one I can think of with a turbo was the Delta S4 which also had a supercharger. So if for no other reason than sound or historical purposes, I think on this car the blower is the way to go.