7A hitachi ecu re-progammeing

[goodall]

I'm currently designing a new intake and exhaust for a 7A for a light weight lotus 7 type replica. since i am changing the dynamics of the engine significantly, I will need to change the map, i am also considering removing the maf or fitting a larger one. Is there any open source information or flashers for the hitachi ecu, seems most stuff I have looked at on the web is for bosch. Anyone got any pointers?

Or would be best getting a cheap ecu set up like mega squirt?

and if anyone asks I know its a hevay engine for lotus 7

[S2central.net]

I know where the main maps are on the 7A and can tweak them real-time with my emulator but you'll need wideband lambda on that thing so that mixture on WOT can be monitored - sounds like an ace project BTW.

Oh the 7A ECU is NOT 'flashable' at all - tis a good old DIL chip in there...

The only issue I have is that I haven't unlocked the secret of a checksum sequence on the 7A chips - I've had a few cracks at it - so it will probably store a stupid fault code about that but thats not going to affect running etc

Lotus 7 with a 7A lump has a certain appeal - fair play for doing something different - is it up and running yet ?

[20Vcqdriver]

Send PM with e-mail address and can send article on fitting larger MAF and of the install of an SMT6 piggy back ECU. You'll also need 034 uprated injectors, but 200bhp is achievable with these simple upgrades. Al extra power however will be at the mid to high rpm which would suit a track car!
Also see http://www.20v-sauger-tuning.de/
Much of this has been covered already... http://www.s2forum.com/forum/showthr...ight=7A+tuning

[goodall]

So the stock ecu seems be from consencous fairly useless from the other thread, I had forgot about that thread and I had posted in it everything. However the way you have changeing the maps Paul sounds tempting for will save me having make a harness and cost a ecu, can the 7A ecu be tweeked for useing a widenand for the lamda on the engine seems been replaced with a second hand one which makes feel mostlikey stuffed almost aswell.
I have all the parts ready and am meant to be getting a chassis of a fella for free however I need design the suspension and steering and make body pannels. However I have got the engine mated up to a ford sierra gearbox. I'm asking about the ecu as I'm planning on designing the tunned intake and exhaust for my final colledge project, so may be able get a free dyno pull paid for but I'll need a ecu to do that

[S2central.net]

That thing will fly on a stock 7A engine... with aftermarket ECU, custom loom and such you could probably extract the max from it. Depends if you want to go to all that hassle for a potential extra 20-30bhp - plus you'll need the wideband lambda gear to do that on aftermarket.

I can tweak the 7A chip in real-time... I'd imagine most gains are going to come from ignition timing as the MAF will compensate for any extra / cold air that you are breathing - just needs a tweak on WOT fuel map. The Hitachi injectors are famous for being a bit useless, so changing to similar size Bosch / Siemens ones would be a good upgrade - this shouldn't require any major change to fuel map when running closed loop with active lambda, but again might need a tickle on WOT to get nice mixture.

I can do hot switchable maps on the 7A as well - so should be easy to test new settings on a dyno if you have one at your disposal... Really need the car to be on the road for realtime tweaking though first to confirm all the maps do as expected, but could be done on the dyno at a push.

[GazzaG60]

a couple of options. smt6 as mentioned to emulate maf signals.

is the 7a batch fire.

if so there is potential to fit a digi-1 harness from a G60. it uses dizzy control and a map potentiometer thats tweakable too so map can be altered like a mixture screw. id sens sns an email and ask.


gettin ggood hp is not an easy task from NA. some vag cars can do it. namely a 2l 16v abf motor will make 170hp with a chip and system. its detuned to sell vr6. this is the tall block but most of the gains are from the management.

cams will be needed for 200hp id expect at a sacrifice of low end power and torque. with NA the engine power is practically defined as is and you can shift the torque up or down the rpm range but not really gain too much without an oil well in the back yard to fund you.

on the inlet front there are really nice pieces from racecraft with nice cut flanges and oval stock. i made one. with help from a mate using the bottom 2 inch of the 16v manifold, 2 inch of a subaru impreza sport inlet for the oval to round transition and jenvey trumpets. ill put it on my avatar so you can take a look as i cant post pics. its no work of art but i like it. first attempt. my mate will use it on 16vt 4x4. clearing the alternator on the valve is the challange to an extent.

[S2central.net]

7A MPI is sequential injection

[goodall]

If switchable makes could be used that would be useful for comparing if I made any improvement with my intake or not, even if results may be slightly skewed. If i keep the audi ecu you will more likely be getting a call for a live mapping session, since you know what you are doing and are relatively local, thats if you want to do a live run in a sub 500kg 200ish bhp space frame as will need to be running before its finished :mischeif:

As for the injectors I was planning on using bosch injectors as was going to design and make a intake manifold plate and fuel rail meaning any injector can be considered.

how much are jenvey trumpets and how thick are they? I'm guessing must be thick enough for welding to? I was looking about on the net yesterday for oval stock for was thinking if were to just crush a piece of tubing the cross sectional area would decrease and cause abit of turbulence, however if done a gentle enough angle could be advantageous. What throttle did you use on the custom intake? I have been looking at mustang/sho ford v8 and honda type R bodies both of which I would imgaine would flow about the right amount

Cams are currently out of the question due to funds, unless the stock ecu can be mapped meaning may be able get a pair of schrick cams with that potential money. Any more info on smt6?

Im hoping for a 400bhp/ton sort of area meaning low 4 secs to 60 and low 12 maybe high 11 quarters. I'm using the diff out of the 90 the engine has come from so the lock can be used keep both wheels moving on launches. however for all that not for track itll be set up to be at home on B roads

[S2central.net]

400bhp/ton go-kart with 5cyl warble has to be a laugh... getting traction if it rains will not be though - LOL.

I'll have a look for suitable Bosch injectors - budget for a variable FPR and FP gauge for good measure as another tweak for fuelling if their is some nonsense inside the ECU maps which make it hard to perfect at WOT.

[S2central.net]

After some searching - this is useful info - http://www.audiworld.com/tech/content_eng83.html

Reverse engineering the numbers we get 300ccpm at 3bar for that injector - 0 280 155 931 - which is from surprisingly exotic source in shape of the GM V8 LS1 engine - the same one that spawned the alternative coilpacks for AAN/ABY.

Looks like 034 have a nice kit sewn up with alloy adapters and the right O-rings to make these injectors properly plug and play on the 7A engine... http://www.034motorsport.com/product...roducts_id=329 - Like most things from 034 they aren't cheap, but they aint horrendous... do NOT waste money the wiring mod though - that is a stupid price.

[S2central.net]

The OFRM for 7A engine clearly states 100-120ml in a 20s injector test with 4bar FPR...
Thats 330ccpm average spec at 4bar (havent found other source yet), but the LS1 injectors will be blowing a theoretical 346ccpm at 4bar so that is in the zone alright. Monsieur Carlier will have done his homework !

[goodall]

So vette injectors are the ticket. I might be able get set second hand with any luck from america along with a nice big throttle of a v8, i guess could get all 8 injectors and would be sure get 5 equally flowing ones. I'm assuming here the parameters for throttle opening on the map can be adjusted for a different pot on the throttle?
As for the adaptors ill only need them if I get lazy and reuse the oem fuel rail (more than likely, if honest)

[S2central.net]

You'd be wise to retain the OE throttle pot - or carefully choose one that closely matches values. Don't forget the 7A also uses a WOT switch on there too. I don't think the throttle body is going to be a big restriction for you - and would advise improving that item before taking on something too radical.

I can help dig up throttle pot spec if you wish.