stepper motor v8 question

[henry-john]

Hi, I'm about to buy a twin plenum from an old rover SD1

now it has the "old" flapper type injection and stepper motor etc...

can I make this plenum work with a newer steppermotor from a hotwire 14SUX?

will it fit?

kind regards and sorry for the silly questions :-)

[Hybrid_From_Hell]

twin plenums can be a nightmare to keep set up / get set up

Is yours a proper one or a home made jobbie ?

Anyway the flapper system had an extar air valve, the hotwire a 4 wire

stepper, and no they are completely differing systems

IMHO this will be troublesome enough to get running nicely, your 1st advisable route is to bin all

the flapper bits and go Hotwire, better still would be to bin all the flapper bits, buy hiotwire

injectors inlet manifold and oplenum and go Megasquirt

Post up a piccie of the plenum that way can identify what it is

Nige

[henry-john]

Post up a piccie of the plenum that way can identify what it is

Nige

this is it...

http://cgi.ebay.co.uk/ROVER-SD1-TWIN-PLENUM-INJECTION-INTAKE-MANIFOLD-TVR-/180556117251?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2a09fbb503#ht_871wt_1139

I wanted it to convert it to hotwire... is this possible?

no home jobby i think....

was my best idea to give the 5.0 some more air...

[henry-john]

as donorparts, got a complete 4.6 out of a P38 incl ALL WIRING

and a complete 14sux hotwire 3,9 engine INCL complete wiring

from all of the above, could I make this twin plenum work with hotwire? (and later MS)

[Hybrid_From_Hell]

OK

OK

I would suggest

Use the 4.6 Block Pistons, sump and timing cover heads etc

Use 3.9 Inlet Manifold Trumpets and a 72mm plenum a la : http://www.v8developments.co.uk/72plen2.png

Use the 3.9 AFM wiring and ECU if you have to, better would be to squirt it - personally

I would bin the GEMS Bits and defo not use them

he twin plenum as the ebay one my look bling but suffered problematic wear in spindles and set up

often needs to be redone all the time, the wear makes relaibility and smoothness an issue, it was

as with many this BL a bit of an exotic bodge if I recall done for the racing teams, they are

collectable, but IMHO For all the wrong reasosn

A 72mm plenum will do fine, use hotwire injectors and if money is spare go for a Hotwire V8 ev Trumpet and inlet manifold

a la : http://www.v8developments.co.uk/inlet2.png and http://www.v8developments.co.uk/tbase2.png the bits at 1st

galnce with your Double plenum don't look diff to standard ?

May be wrong, but would need much closer inspection.

The flapper injectors are Bosch, hideously expensive, and the AFM and ECU Noahs cast offs, a bit pile of trouble, and will

under fuel a 5.0 lump, as will a 3.9 ECU too, but that can be ERPOMed if you mad enough to go that route

Nige

[henry-john]

d if you mad enough to go that route

Nige

mad enough

will probably first eprom the thing, (normally got an ECU WITH the engine)

and MS is on the list, but will come over when I got the cash

first of all, now I'm looking to re-use the TVR headers and downpipe to get a better gasflow than the original so called spaghetti headers....

thx nige!!

always a big help.... next time I'll PM you instead of asking here

thx

HJ

[Hybrid_From_Hell]

EPROM will be from memory £300-£400 will still be a bodge

Why waste the money ?

Sell all the bits you don't need and with that and what you'll save EPROMing mapping etc

you'll have enough to squirt it ?

Seriously think !

Your not going to get an off the shelf chip for a 5.0 4.6 headed 3.9 72mm plenum big trumpeted ported

inlet system off the shelf, to make it work you'll need rolling road time, VERY Expensive - ie £100 hr

is not unknown for kit and Guru to get it sorted, and count on a few hours

NOTE : You and others should ALWAYS ask here, and not via PM< others will find the above of

some use, and inctrease knowledge base, after all LR4x4 is the Tech LR / 4x4 Forum,

Nige

[Range Rover Blues]

I'd ask RPI about a chip, £340 IIRC and they are programmed by Mark Evans who also sells them directly if you can contact him. Modifications including Bosch pintle injectors/naughty cams, 5.2 rebores, BVH and sports exhausts are all common enough for the chip to be programmed to suite. It does after all have limited learning ability.

Serious tuners bin the disk style injector because raing the fuel delivery pressure makes it harder for the injector to open so they inject less fuel. They were fitted becasue they are quiet.

One of the big limits to the hot wire is the AFM diameter, they can be rebored or replasced with P38 meters and agian the chip needs programming accordingly.

TVR can wring over 300BHP out of the hot wire system. Its a very simple system, it fires in banks rather than being a fully sequential system so it can't mathc later EFi for emissions or economy but it is simple and easy to maintain, plus it's well understood by tuning companies.

Out of interset what sort of power are you getting form the 5.0 litre and what mods have you done already>

[Hybrid_From_Hell]

Ah RPI

Not the bestest reputation from a few V8ers here

always wondered if the company name is an anagram

Nige

[Range Rover Blues]

Then ask JE Engineering, John Eales was the guy LR asked to develop the 4.2 in the first place.

[FridgeFreezer]

TVR can wring over 300BHP out of the hot wire system

TVR's marketing department can certainly wring 300bhp out of 200bhp

£350 for a chip to bring a 20 year-old system closer to being right, or a similar amount for MS which can be tuned exactly to your engine and loses the airflow meter, works with any injectors you choose - then again, with it set up properly tuning bodges like raising the fuel pressure, fitting bigger injectors etc. needn't be done in the first place.

[Hybrid_From_Hell]

Then ask JE Engineering, John Eales was the guy LR asked to develop the 4.2 in the first place.

[ Extreme anorak Mode on ]

John USED to work for JE Engineering,

then he "Left" .... setting up his own company 'JED' John Eales Developments.

You'll find he "Reacts" slightly differently if you mention both companies

[/anorak mode off and back in cupboard ]

[Range Rover Blues]

Hang on, EFi without a mass air flow meter? how does that work then?

[FridgeFreezer]

Hang on, EFi without a mass air flow meter? how does that work then?

http://en.wikipedia.org/wiki/MAP_sensor

As used on the Freelander.

[Range Rover Blues]

Another reason not to buy a freelander then. That's how (one of the ways) that EECIV works in limp-home mode when the MAF sensor is bust. It's an incredibly comlicated, inaccurate way of measuring MAF which is after all the thing you need to know.

[Bowie69]

That or MAP + air temp (therefore density)

MAP sensors are a tenth of the price of a MAF, I know what I would rather have.

[FridgeFreezer]

Another reason not to buy a freelander then. That's how (one of the ways) that EECIV works in limp-home mode when the MAF sensor is bust. It's an incredibly comlicated, inaccurate way of measuring MAF which is after all the thing you need to know.

I have to say you're not exactly convincing me on your vast knowledge of these sorts of systems - a lot of cars use MAP sensors, have done for years. Some use both MAP and MAF. Many aftermarket systems use MAP sensors.

Are you sure you're not thinking of Alpha-N, which only uses RPM and throttle position and works the maths out from there - not ideal but sometimes useful on engines which are so lumpy you can't get a stable airflow reading.

MAP sensed systems are not complicated, they're pretty simple really - certainly the maths is no harder one way round than the other. MAP sensing has the advantage that the MAP sensor doesn't have to be in the airflow and can also be pretty small & robust. As for accuracy, if you're asking the question then I would think hard about how accurate a MAF sensor can ever really be - the flapper type is just horrible, the hotwire types are effectively measuring air flow by sticking their finger in the air and seeing how cold it gets, doesn't sound like the ultimate formula for accuracy in my book.

I should point out that I'm not saying either is better than the other - mainly because car manufacturers themselves seem to use both in pretty equal measure and both seem to work prefectly well.

My personal view is that MAP makes a lot of sense in an off-road car as the sensors are more robust, can be remotely mounted (FL one is inside the ECU) and not in the direct airflow where ingested crud could harm them.

[Range Rover Blues]

Flapper sytems are voumetric air flow, not mass air flow. To calculate gravimetric air to fuel ratio you need to know the mass of air and fuel. Air is compressable whilst fuel is not, so unless you know the mass of air you have to know both volume and density because pressure and temperature change the relationship between the 2.

I learned that much whilst getting my degree in this stuff.

I'd agree that MAF are more prone to damage than MAP which is one reason the later still get used, but "sticking your finger in and seeing how cold it gets" is a very accurate way of measuring mass flow, seeing as the amount of heat energy absorbed by the passing air is directly proportional to the mass of air traveling past.

Far more intersting is the Karman vortex meter, as used on the Mitsubishi Evo IIRC, and the cold wire mass air flow meter as used by Holden.

[FridgeFreezer]

Hang on, EFi without a mass air flow meter? how does that work then?

I learned that much whilst getting my degree in this stuff.

Not sure what your degree's in but I'd assume it can't have been modern engine management systems if MAP sensors are new and scary. I've always heard flapper/hotwire referred to as MAF. Although the flap itself can't measure density, that's calculated from the air temperature sensor just as it is with MAP systems.

[Range Rover Blues]

I keep making the mistake of coming in here wihout my handbag!

My degree is in mechanical Engineering and Automotive design, I used to build and test engine management systems as part of my job. Flapper system measure volumetric flow, so they are called VAF meters.

[FridgeFreezer]

Flapper system measure volumetric flow, so they are called VAF meters.

They may be VAF meters but the system as a whole is MAF, as you said, you need to know the total amount of air not just the volume or pressure.

[Hybrid_From_Hell]

I always remember a quote poked at me years ago re a "Qualifications" row at work Old boy in the corner piped up with "Guys who made the Titanic - they all had qualifications and Noah had none:lol: " Nige

[FridgeFreezer]

I should say, before this thread goes totally off into the weeds, that I'm not after a handbag fight - but when you come out with sweeping statements like "MAP = rubbish" on the internet, someone's going to question you

Oh and I have a GCSE in art.

[V8david]

Oh and I have a GCSE in art.

Brilliant.