Bits to get for engine?

[billoddie]

Hi guys.
I have the chance to purchase some engine parts atm, but want to make sure i get only those I really need.
As you know, I have a stock 1996 3.9 that is to be the basis for a rebuild of sorts.
Which of the following parts would/could be useful for this motor?
1.Hotwire Injection system...with airflow meter, computer and loom...rising rate fuel pump.
2. Mallory ignition system
3. four litre forged cosworth pistons
4 Rocker shafts
5. Head gaskets.

Presently I am inclining toward the rocker shafts/gaskets as definates.
The Mallory ignition I think I would like as long as it offers benefits over and above the stock electronic dizzy (35d8) ??
I dont know much about the hotwire injection, but I think I will need to obtain at least a stock computer/loom anyways, so maybe it could be a good buy...again if it has clear benefits above and beyond the stock system.
Also, where is the airflow meter on these things? Is the hotwire one a worthwhile upgrade?

The Cosworth pistons are high com items, and means the motor would require a rebore for them to fit...does the motor require one anyways as part of a rebuild, or just a hone?

Suggestions in parts suitability appreciated thanks.

 

[harveyp6]

My two cents worth.

The Hotwire system is a good idea, (but I would have thought your engine would be fitted with that already), I'd forget the Mallory, and the Cosworth pistons, (as the 3.9's can have liner problems as standard so reboring and hence thinning the liner could make that a lot more likely). I never rebore V8's, if they need more than a hone I throw them away and start with another one. The running clearances are too critical and getting someone who knows that to rebore them can be difficult.
Rocker shafts and gaskets are normal rebuild items so I'd have those.

 

[billoddie]

Hi Harvey.
Thanks for your reply.
My main problem here is that I know very little about engine bits and pieces, and find it all a little confusing atm (hotwire 14cux vs flapper...10 bolt vs 14 bolt...torque to yield headbolts blah blah blah :shock: ) so mine very well may have the Hotwire.
From what I can gather, It seems i am missing the ECU, and the airflow meter...will investigate a little more.
In regards the Mallory...could you tell me why you would leave it? I will
Appreciate your feedback.
Oh, the chap also has a new SD1 camshaft...is that a good choice? My main aim is torque/midrange...

 

[quattro]

It all depends on how much he wants for this stuff.

The 3.9 and 4.0 have the same bore and stroke, so I would have thought the pistons would fit, but they really aren't necessary for a mildly tuned engine. I certainly wouldn't rebore it.

The Rover electronic dizzy is a very good distributor, and designed for the engine. The Mallory, although renowned for its quality, is more of a general purpose one. Is it an electronic one, or dual point? If the latter, then the SD1 one will outperform it. Sparky came with a twin point Mallory and I binned it for the SD1 electronic one. It made a tremendous improvement.

After reading upon the EFI it seems to be generally accepted that the Hotwire system is better than the flapper, and a lot better at that. Does it come with a carb set up as well, or just the EFI? Will you run it with the Rover ECU, or megasquirt?

Richard

 

[billoddie]

Hi Richard.
Im willing to spend $500...so whatever that will get me.
The chap is moving house, so he is a motivated seller..(he really wants to get rid of the short motor with the Cossie pistons, coz its a bit of a lump to move about i guess).
I can get a Rover ecu for about $65, so the Megasquirt would have to offer advantages that are clear and defined for the extra $$$.
Im not planning to run a carb setup...i want to keep it all simple and reliable.
Just a matter of getting everything lined up in terms of where to spend $$$.

 

[quattro]

I'm not really sure what you have there Bill.

You say that you have a 3.9 motor to rebuild, but then there are 4L Cossie pistons on offer, but then a 4L short motor with Cossie pistons.

Do you have the complete 3.9, and then a separate Hotwire EFI system as well?

Does the engine already have a distributor, and the Mallory is an extra? and is it a twin point?

If he is that 'motivated' offer him the $500 for the lot and then put what you don't need on ebay

Richard

 

[billoddie]

Yeah...bit of a hotchpotch.
I have a stock 3.9 to rebuild from 94 Discovery (I think...maybe 96)...its minus ECU/air meter/airbox
He has various bits and pieces suitable to what I need...but also has a 3.5 short motor that has been bored to 4.0 litres with Cosworth forged high comp pistons. Also has a complete Hotwire inj system and Mallory hyfire ignition.
SD1 camshaft...headgaskets...rocker gear...and a box of sundry items.
Its a matter of picking and choosing what i want/need.
(Which can be entirely different)

 

[quattro]

Ok got it LOL

Forget the bored out 3.5, that sounds like a whole bag of worms :shock:

If you already have a Hotwire system, just ask him for bits you need, but if you have a flapper system on your 3.9, go for the Hotwire.

I know nothing at all about the Hyfire system so cannot comment on that. Does the 3.9 have a distributor, or is the ECU running the igntion?

Is the SD1 camshaft for the 3.9 or a 3.5?

Richard

 

[corazon]

Mallory hyfire is the equivalent of MSD 6al capacitive discharge ignition boxes, can be used as a form of electronic ignition when retaining points.
But can also be used with fully electronic ignitions as an amplifier
Sounds like you have too many options Brenten!
Jim

 

[billoddie]

Ok...this is what I have

 

[billoddie]

So...I'm a bit confused.
It seems I DONT need an ecu...just the dizzy cap and that plastic thing thats a bit smashed.
I need the airbox and airflow meter (?) I think.
Or should i get the whole new Hotwire system and junk the dizzy way?
Chap wants $400 for it (its new)...I want to pay 300. (Cost 1100 apparently...from TR Spares)

 

[corazon]

Brenten, you're still gonna need an ECU to control the fueling.
Depending on how cheap you can source one, it might make more sense to get the complete system and resell some of what you have/keep as spares..
Jim

 

[billoddie]

Hi Jim.
I can get an ecu for $65.
I assume I will still need an airflow meter...if so, its about $95.
Whilst I would like the new and complete Hotwire system, as it transpires, it seems the bits i need wont cost too much anyways.
Thanks for clarifying things guys...as Jim said...too many choices.