390SE on the rolling road - at last
Discussion
So a two year wait to eventually get a session with Mark Adams and Tornado Systems for the 390SE and a good day was had. Engine itself is in rude health with no issues. Started the day with 213bhp and finished with 247bhp once AFM and fuel mixture was all set correctly. The car has been transformed. No more low rev shunting. The engine pulls from low revs in all gears and just revs its nuts off without hesitation. A top day and also amazingly interesting. The 900bhp Dodge Charger was something to behold.......
Sounds great - we could probably all do with this. What adjustments were made we want all the gen on it... On the graph, what is the really wiggly line?
Just think, when you get that 10kg of dirt off the rear the acceleration will be even better!
Just think, when you get that 10kg of dirt off the rear the acceleration will be even better!
Edited by adam quantrill on Friday 9th February 19:48
Yes, tell us a little more please Keith. How long did it take? How much did it cost? What part of the country are they in? I am considering a rolling road and reset on my 400SE. Although it runs well without hesitation, the idling can sometimes be erratic and it’s never had a tune during my ownership. I once had a 350SE with a Mark Adams chip and it performed really well. Do they still do that to increase performance? I’d be very interested. Cheers.
Tony. TCB.
Tony. TCB.
253 Nm of torque to be precise. Although car ran okay previously it never felt right with bugger all low end power delivery below 2500rpm and horrendous fuel consumption (12 mpg!). Mark suggested a few more horses are available with the larger Jaguar AFM. I managed to pick one up and a previously modified Tornado ECU for £70. Mark lives about 20 miles from me so the other year I did drop off the AFM and ECU for him to check. The ECU was mapped to suit the larger jag AFM, standard injectors and V8 developments Stealth camshaft.
I've run a standard ECU and AFM since I had the car but today involved a 10 minute swap over of the ECU and larger AFM and then a half day setting it all up. Basically Mark charges while he works on the car but he had lots of other things to keep himself busy while Mike, the owner of Shropshire Automotive in Shrewsbury, did the power runs to get lambda and hydrocarbon levels more acceptable.
Basically they went through the ignition system, injectors, timing etc with a fine tooth comb, ensured everything was working as it should. They then do a few power runs and then compare each spark plug to ensure that they are all received the same mixture. If an injector has a poor spray pattern they can tell from the spark plug supposedly.
Once they were happy with the basics it was a number of power runs to set the fuel pressure correctly (started at 45psi but was brought down to 36psi). Then it was a matter of fine tuning the AFM for both mixture at tickover and then mixture throughout the rev range to get the optimum internal spring setting. Hydrocarbons started at over 2000ppm (MOT failure figure is 1200ppm!) but by the end of the session we were down to around 1000ppm.
Excluded the new battery, as the bloody car died on their forecourt with terminal battery failure!, total cost was just over £550. That was for basically all afternoon on the rolling road, several power runs, 4 hours of Mikes time and 2 hours of Marks time.
The car is utterly transformed. It now pulls like a train from very low revs (600rpm), revs pick up at a ridiculous rate and the engine sounds as sweet as..... Seriously well impressed.
I've run a standard ECU and AFM since I had the car but today involved a 10 minute swap over of the ECU and larger AFM and then a half day setting it all up. Basically Mark charges while he works on the car but he had lots of other things to keep himself busy while Mike, the owner of Shropshire Automotive in Shrewsbury, did the power runs to get lambda and hydrocarbon levels more acceptable.
Basically they went through the ignition system, injectors, timing etc with a fine tooth comb, ensured everything was working as it should. They then do a few power runs and then compare each spark plug to ensure that they are all received the same mixture. If an injector has a poor spray pattern they can tell from the spark plug supposedly.
Once they were happy with the basics it was a number of power runs to set the fuel pressure correctly (started at 45psi but was brought down to 36psi). Then it was a matter of fine tuning the AFM for both mixture at tickover and then mixture throughout the rev range to get the optimum internal spring setting. Hydrocarbons started at over 2000ppm (MOT failure figure is 1200ppm!) but by the end of the session we were down to around 1000ppm.
Excluded the new battery, as the bloody car died on their forecourt with terminal battery failure!, total cost was just over £550. That was for basically all afternoon on the rolling road, several power runs, 4 hours of Mikes time and 2 hours of Marks time.
The car is utterly transformed. It now pulls like a train from very low revs (600rpm), revs pick up at a ridiculous rate and the engine sounds as sweet as..... Seriously well impressed.
Sounds good...Timing does reveal some hidden horses...Your fuelling was definitely too high at 45psi..thats more 450 territory..I know when mine was running badly lean I seemed to of had higher revs but once it was set correctly I lost higher revs but definitely gained low down grunt...
That cam sounds a good investment..Well done for sticking with it....
That cam sounds a good investment..Well done for sticking with it....
The power is about right but that fuelling curve has never seen mapped! It's all over the shop, a mapped fuel curve is just that, a curve, not a sawtooth wave.
The fueling can't really be mapped on a 4cu anyway as it's not an eprom but you can alter;
Air density correction slope
Air density correction offset
Throttle enrichment %age threshold
Full throttle enrichment %
Afterstart enrichment taper time and %age
Pumpshot pulsewidth
and that's about it. Doing any of the above requires opening up the ecu and soldering new component values in/out. I suspect the OP has had a very expensive full days worth of adjusting the fuel pressure regulator and some supporting theatre.
mrzigazaga said:
Your fuelling was definitely too high at 45psi..thats more 450 territory
Not true if we're talking the flapper system. The absolute max pulse width on a 4cu is 10ms, and to make 270lb/ft on the standard 105 injectors and a 10ms PW you need 55 psi +/-3.The fueling can't really be mapped on a 4cu anyway as it's not an eprom but you can alter;
Air density correction slope
Air density correction offset
Throttle enrichment %age threshold
Full throttle enrichment %
Afterstart enrichment taper time and %age
Pumpshot pulsewidth
and that's about it. Doing any of the above requires opening up the ecu and soldering new component values in/out. I suspect the OP has had a very expensive full days worth of adjusting the fuel pressure regulator and some supporting theatre.
baracus said:
Not true if we're talking the flapper system. The absolute max pulse width on a 4cu is 10ms, and to make 270lb/ft on the standard 105 injectors and a 10ms PW you need 55 psi +/-3.
The fueling can't really be mapped on a 4cu anyway as it's not an eprom but you can alter;
Air density correction slope
Air density correction offset
Throttle enrichment %age threshold
Full throttle enrichment %
Afterstart enrichment taper time and %age
Pumpshot pulsewidth
and that's about it. Doing any of the above requires opening up the ecu and soldering new component values in/out. I suspect the OP has had a very expensive full days worth of adjusting the fuel pressure regulator and some supporting theatre.
Thank you for your positive contribution. Mark previously has adjusted the ECU to match my engine components. He did admit that this entailed soldering alternative resistors into the circuits. As far as I am concerned the car is totally transformed and given feedback from several other fellow Wedge members who have had similar experiences for me this is money well spent. If you'd like to discuss further then more than happy to meet up at the next BBWF face to face,The fueling can't really be mapped on a 4cu anyway as it's not an eprom but you can alter;
Air density correction slope
Air density correction offset
Throttle enrichment %age threshold
Full throttle enrichment %
Afterstart enrichment taper time and %age
Pumpshot pulsewidth
and that's about it. Doing any of the above requires opening up the ecu and soldering new component values in/out. I suspect the OP has had a very expensive full days worth of adjusting the fuel pressure regulator and some supporting theatre.
I also note that this is your first contribution in 151 months. You may not be aware that we try to all offer advice and share our experiences on this forum. My experience today has been extremely positive. I'm keen to understand your Wedge related experiences or alternatively your expertise in the wonders of the Rover fuel injection systems. There are several experts on this forum who would be keen to learn from your wisdom. Do you have a website or proven experience in this field, as Mark Adams can clearly demonstrate?
KKson said:
I also note that this is your first contribution in 151 months. You may not be aware that we try to all offer advice and share our experiences on this forum. My experience today has been extremely positive. I'm keen to understand your Wedge related experiences or alternatively your expertise in the wonders of the Rover fuel injection systems. There are several experts on this forum who would be keen to learn from your wisdom. Do you have a website or proven experience in this field, as Mark Adams can clearly demonstrate?
I lost my other account with several hundred posts so reverted to this old one. I can let everybody know exactly which transistors and resistors to change if you'd like.It still stands that that ecu isn't mapped;- 11:5 afr down below 3000rpm is far far too rich, your losing 10-15 lb/ft below 3000 due to that. From that graph your fuelling is good above 4400rpm.
I only add this as i was hoodwinked by someone installing and twidling with a FPR for half a day ( not MA i might add) and as a result i had to learn how the ECU system worked to get it right.
Edited by baracus on Saturday 10th February 01:40
baracus said:
The power is about right but that fuelling curve has never seen mapped! It's all over the shop, a mapped fuel curve is just that, a curve, not a sawtooth wave.
The fueling can't really be mapped on a 4cu anyway as it's not an eprom but you can alter;
Air density correction slope
Air density correction offset
Throttle enrichment %age threshold
Full throttle enrichment %
Afterstart enrichment taper time and %age
Pumpshot pulsewidth
and that's about it. Doing any of the above requires opening up the ecu and soldering new component values in/out. I suspect the OP has had a very expensive full days worth of adjusting the fuel pressure regulator and some supporting theatre.
Ahh okay...My 350i flapper doesn't like it anything over 38psi..Over a year she became very lean..not sure if thats wear on the AFM spring?..It has been adjusted up and all good now though.mrzigazaga said:
Your fuelling was definitely too high at 45psi..thats more 450 territory
Not true if we're talking the flapper system. The absolute max pulse width on a 4cu is 10ms, and to make 270lb/ft on the standard 105 injectors and a 10ms PW you need 55 psi +/-3.The fueling can't really be mapped on a 4cu anyway as it's not an eprom but you can alter;
Air density correction slope
Air density correction offset
Throttle enrichment %age threshold
Full throttle enrichment %
Afterstart enrichment taper time and %age
Pumpshot pulsewidth
and that's about it. Doing any of the above requires opening up the ecu and soldering new component values in/out. I suspect the OP has had a very expensive full days worth of adjusting the fuel pressure regulator and some supporting theatre.
Thanks for the info...
Ziga
Something not adding up here. With the standard AFM and standard ECU in order to get the mixture correct I had a fuel pressure of 45psi. Mark Adams did say that he'd modified the replacement ECU to allow longer injector opening time so that fuel pressure could be reduced. At 45psi the HC's were through the roof. The fuel pressure was progressively dropped until the HC and lambda were where they should be and this corresponded to a fuel pressure of 36psi. After a 90 minute drive home the plugs look absolutely spot on colour wise.
Anyway everyone is entitled to their opinion. The engine had a very thorough point by point check as they went through the various components, HT system, injector performance, camshaft timing, compression check, engine vacuum check, AFM track condition, AFM voltage output across the full range of operation etc. This was before they adjusted the AFM for idle mixture and mixture across the range.
I'm more than happy with the results.
Anyway everyone is entitled to their opinion. The engine had a very thorough point by point check as they went through the various components, HT system, injector performance, camshaft timing, compression check, engine vacuum check, AFM track condition, AFM voltage output across the full range of operation etc. This was before they adjusted the AFM for idle mixture and mixture across the range.
I'm more than happy with the results.
mrzigazaga said:
Ahh okay...My 350i flapper doesn't like it anything over 38psi..Over a year she became very lean..not sure if thats wear on the AFM spring?..It has been adjusted up and all good now though.
Thanks for the info...
Ziga
Yes Ziga, the stock settings should be ballpark correct for the 350i as the engine in that is effectively the same as the rover sd1, so stock calibrations are correct.Thanks for the info...
Ziga
Increased pressure is for the more powerful engines i.e. the 390se. Initially i believe TVR intended to use higher flow injectors (237cc/min) from the Jaguar Xj6 series 3 4.2litre to get sufficient fuelling, however supplies of these injectors dried up (somewhere around 1985) so TVR reverted to the stock range rover injectors (190cc/min). Only around 20-30 390se's out of 100 odd had been built by the time they started using standard RR injectors, so chances are most SE's don't have the uprated injectors.
You can't get enough fuel to achieve 270lb/ft 275hp on 190cc/in injectors on stock fuel pressure, so an increase to the fuel pressure to 55psi gives an effective injector flow rate of 235cc/min where New Fuel flow= SQRt (55/36)x190cc
baracus said:
You can't get enough fuel to achieve 270lb/ft 275hp on 190cc/in injectors on stock fuel pressure, so an increase to the fuel pressure to 55psi gives an effective injector flow rate of 235cc/min where New Fuel flow= SQRt (55/36)x190cc
Makes sense...I have noticed that having an adjustable FPR made a noticeable difference to the responsiveness of throttle opening and also at WOT...Mine made 184 bhp and 220ftlb a couple of years ago which is not too grim for a 30 year old stock 350i..I had the FP set to 41psi WOT..although this gave 2 horses more it caused over-fuelling, and a flat spot at anything over 50mph in 4th.. so now sits happily at 38-39psi WOT...I have seen some Wedges with various upgraded ECU's...from Haltech...Vip-tech..through to MS2..I have to say they ran the sweetest idle which was at least 100rpm lower than recommended....I might go that route if I ever change the cam and fit some big valve heads...porting...polishing...Maybe some rifled/helix-coiled vaned inlet ports ..Maybe a minute bit of latency of the outlets....Not too much though...
...Sound like a proper cannon banging that throttle down...Mind you I know how expensive forced induction is so maybe just pootle around as is for a while...
Thanks for the knowledge...
Ziga
Glad you finally got sorted Keith, even more so with the finished result! that's one strong wedge. Mike's rolling road doesn't exaggerate figures either in my experience.
Do you have pocketed pistons to go with that Stealth Cam or can you get away without having them?
Great results anyway!
Steve H.
Do you have pocketed pistons to go with that Stealth Cam or can you get away without having them?
Great results anyway!
Steve H.
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