RV8 3.9 Timing Cover on a 4.6 Block

General Chat About Engine Build

Moderator: phpBB2 - Administrators

garrycol
Getting There
Getting There
Posts: 347
Joined: Thu Jul 16, 2015 2:47 pm
Location: Australia

RV8 3.9 Timing Cover on a 4.6 Block

Post by garrycol » Thu Apr 11, 2019 8:13 am

I am wanting to put a distributor on a 4.6 block which has a 4.6 Crankshaft and 4.6 Camshaft.

I have a 3.9 timing cover and would like to put that on the front of the 4.6 so that it can drive a distributor. So three questions:

1. I assume a cam shaft with a dissy drive is required. I did hear somewhere that there is an adaptor that can go in but I have only heard of that once and assume this is not the case and a new camshaft is needed.

2. The 4.6 crankshaft has a shorter front end than a 3.9/3.5 crankshaft and I understand an adaptor is needed so the crank pulley can bolt up with the thicker timing cover. Does anyone have dimensions of this adaptor? or where they can be purchased.

3. Other than the camshaft and crankshaft extension, are there any other issues to be considered?

Thanks

Garry



User avatar
stevieturbo
Forum Contributor
Forum Contributor
Posts: 3550
Joined: Sat Nov 18, 2006 6:22 pm
Location: Northern Ireland

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by stevieturbo » Thu Apr 11, 2019 10:46 pm

Is there a necessity for a dizzy ?

Modern crank based ignition is easy to do.
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

garrycol
Getting There
Getting There
Posts: 347
Joined: Thu Jul 16, 2015 2:47 pm
Location: Australia

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by garrycol » Fri Apr 12, 2019 1:43 am

I suppose you are thinking megajolt and trigger wheels etc - not keen on these as there is no expertise locally.

If you have other off the shelf options I would be glad to consider those - I already have the timing cover, dissy and cam just not the crankshaft spacer.

Cheers

Garry

unstable load
Top Dog
Top Dog
Posts: 1211
Joined: Mon May 04, 2009 6:53 am

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by unstable load » Fri Apr 12, 2019 4:23 am

What vehicle is it for?
Can't you use the GEMS/Thor flywheel or auto drive plate with it's built in trigger setup and the OEM engine ECU?
Cheers,
John

garrycol
Getting There
Getting There
Posts: 347
Joined: Thu Jul 16, 2015 2:47 pm
Location: Australia

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by garrycol » Fri Apr 12, 2019 7:30 am

The engine is a Landrover 101 - it has a 3.5 manual flywheel. It is a project not running.

It currently has a trigger wheel, Edis 8 (in default) and coil packs - it has virtually no spark and cylinders 1 and 6 (wasted spark pair) have no spark at all - not the spark plugs as they are new and work fine, the leads are OK - the issue is in the trigger wheel (not sure I have that right), the sensor, edis 8 module or the coil packs.

I am currently pulling it all back out and rewiring it to see if that is an issue - unfortunately I am not familiar with this kit where I am with dissys etc and there is no local expertise on megasquirt and megajolt in my area.

Other than the wiring I do not know how to test the Edis module or the coil packs.

Unless the Motronics ECU is heavily modified they do not work in isolation from the donor vehicle .

Thanks

Garry

DaveEFI
Forum Contributor
Forum Contributor
Posts: 4075
Joined: Fri Feb 26, 2010 4:27 pm
Location: SW London, UK

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by DaveEFI » Fri Apr 12, 2019 8:52 am

If the trigger wheel and sensor are already fitted (correctly) the difficult bit is done. To check this, turn the engine to TDC. The sensor should line up on the 5th tooth anti clockwise (looking at the front of the engine) from the missing one. Set the sensor gap to 1mm and check it is +/- 0.5mm on other teeth (say every 9th tooth) to check the wheel is centred.

Here's my drawing of the EDIS 8 schematic. If it's not too good as a JPG, PM me with your email and I'll send a PDF which is much better quality.

Image

Generally EDIS is pretty reliable and long lasting. You may have to try swapping the sensor connections if you still don't get a decent spark, and everything else is OK.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y

garrycol
Getting There
Getting There
Posts: 347
Joined: Thu Jul 16, 2015 2:47 pm
Location: Australia

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by garrycol » Fri Apr 12, 2019 10:53 am

Thanks Dave - I already have those diagrams.

One possible issue is that I cannot get the sensor closer than 2mm from the trigger teeth. Originally I could not get it closer than 5mm with the standard mounting brackets bolted to the correct holes on the engine block. I have I have modified the standard mounting by elongating the holes and got to 2mm. As well as checking the wiring tomorrow I will re-calibrate the trigger wheel and the sensor - unfortunately the engine never had TDC marks and I calculated where it should be using one of the recommended methods but maybe the TDC mark I determined is not totally correct but should be within 5 degrees.

Cheers

garry

DaveEFI
Forum Contributor
Forum Contributor
Posts: 4075
Joined: Fri Feb 26, 2010 4:27 pm
Location: SW London, UK

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by DaveEFI » Fri Apr 12, 2019 12:56 pm

I've not experimented with the sensor gap, but the spec I have is from 0.5 - 1.5mm (0.030-0.060") So generally just set it to 1mm, and check it is OK on other teeth. If you still have trouble getting a reliable spark, try swapping the VR polarity.

Lots on the MS forum will say not to use EDIS. Starting with a clean sheet, I'd likely not either. But since you already have it, no reason why it won't be fine on a low revving unit like the 4.6. It's worked just fine on my Vitesse engine for many a year - although since I have the MS upgrade bug, I'm going to go MS3 and sequential everything using active coils, when I fit my new engine.

If going for a blower, wasted spark may not be ideal, though.

FWIW, I don't know of anyone who has fitted MS to a Thor manifold. Likely because the Bosch system works just fine - unlike the earlier Lucas. But can't see any problems in doing so - I've got a complete Thor manifold etc here. And it has better idle control than the earlier systems.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y

SuperV8
Guru
Guru
Posts: 776
Joined: Tue Jul 07, 2009 11:25 pm
Location: West midlands

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by SuperV8 » Fri Apr 12, 2019 1:03 pm

It currently has a trigger wheel, Edis 8 (in default) and coil packs - it has virtually no spark and cylinders 1 and 6 (wasted spark pair) have no spark at all - not the spark plugs as they are new and work fine, the leads are OK - the issue is in the trigger wheel (not sure I have that right), the sensor, edis 8 module or the coil packs.
So is has a weak spark on all but cyl 1 and 6?
What ECU is triggering the EDIS module?
Dax Rush 4.6 supercharged V8 MSII

User avatar
stevieturbo
Forum Contributor
Forum Contributor
Posts: 3550
Joined: Sat Nov 18, 2006 6:22 pm
Location: Northern Ireland

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by stevieturbo » Fri Apr 12, 2019 3:12 pm

There really isnt anything on a basic crank based ignition setup that needs any expertise. It should be very easy for most anyone to get it up and running, especially the likes of megajolt etc.

They are just easy systems

If budget permitted, then there are Aussie based makers of various ecu's where local support should be easy, but there shouldnt be any real need to go that far if indeed you just purely want ignition control.
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

DaveEFI
Forum Contributor
Forum Contributor
Posts: 4075
Joined: Fri Feb 26, 2010 4:27 pm
Location: SW London, UK

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by DaveEFI » Fri Apr 12, 2019 3:37 pm

Although it's pretty much for DIY electronics types, the Speeduino project is interesting, and has an Oz following. And is very low cost, being based on the Arduino. Not sure if it could be used with EDIS for ignition only, but would guess it could.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y

DaveEFI
Forum Contributor
Forum Contributor
Posts: 4075
Joined: Fri Feb 26, 2010 4:27 pm
Location: SW London, UK

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by DaveEFI » Fri Apr 12, 2019 3:48 pm

SuperV8 wrote:
Fri Apr 12, 2019 1:03 pm
It currently has a trigger wheel, Edis 8 (in default) and coil packs - it has virtually no spark and cylinders 1 and 6 (wasted spark pair) have no spark at all - not the spark plugs as they are new and work fine, the leads are OK - the issue is in the trigger wheel (not sure I have that right), the sensor, edis 8 module or the coil packs.
So is has a weak spark on all but cyl 1 and 6?
What ECU is triggering the EDIS module?
EDIS is a (nearly) stand alone system. It will produced a fixed timed spark (10 BTDC, as a limp home feature) with no external ECU.
The EDIS module sends a tach signal (PIP) to the ECU, and the ECU then sends back a control signal (SAW) to the EDIS module which does the timing advance.

This simplicity is why it is (was) so popular for non OEM use, as it decodes the crank trigger into a simple pulse to send to the ECU - often what trips people up with MS, etc. It's also pretty bomb proof.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y

garrycol
Getting There
Getting There
Posts: 347
Joined: Thu Jul 16, 2015 2:47 pm
Location: Australia

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by garrycol » Fri Apr 12, 2019 11:10 pm

SuperV8 wrote:
Fri Apr 12, 2019 1:03 pm
So is has a weak spark on all but cyl 1 and 6?
What ECU is triggering the EDIS module?
It has no spark on cyl 1 and 6 and weak spark on the rest. EDIS is operating in default mode so no ECU is attached.

SuperV8
Guru
Guru
Posts: 776
Joined: Tue Jul 07, 2009 11:25 pm
Location: West midlands

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by SuperV8 » Mon Apr 15, 2019 7:22 am

DaveEFI wrote:
Fri Apr 12, 2019 3:48 pm
SuperV8 wrote:
Fri Apr 12, 2019 1:03 pm
It currently has a trigger wheel, Edis 8 (in default) and coil packs - it has virtually no spark and cylinders 1 and 6 (wasted spark pair) have no spark at all - not the spark plugs as they are new and work fine, the leads are OK - the issue is in the trigger wheel (not sure I have that right), the sensor, edis 8 module or the coil packs.
So is has a weak spark on all but cyl 1 and 6?
What ECU is triggering the EDIS module?
EDIS is a (nearly) stand alone system. It will produced a fixed timed spark (10 BTDC, as a limp home feature) with no external ECU.
The EDIS module sends a tach signal (PIP) to the ECU, and the ECU then sends back a control signal (SAW) to the EDIS module which does the timing advance.

This simplicity is why it is (was) so popular for non OEM use, as it decodes the crank trigger into a simple pulse to send to the ECU - often what trips people up with MS, etc. It's also pretty bomb proof.
Yes, Thanks Dave for making my point clearer - I understand this, I was referring (maybe to simply) to control signal when I mentioned about the ECU trigger. So currently this install would be just running a fixed 10deg advance.
Dax Rush 4.6 supercharged V8 MSII

User avatar
ChrisJC
Top Dog
Top Dog
Posts: 4613
Joined: Mon Nov 20, 2006 1:13 pm
Location: Northants / Cambs
Contact:

Re: RV8 3.9 Timing Cover on a 4.6 Block

Post by ChrisJC » Thu Apr 18, 2019 8:22 pm

You can fit the 3.9 timing cover on the 4.6 block. From memory you need:
- Countersink one of the crossbolts and fit the same type of crossbolt as that found by the starter.
- Change the camshaft for one that will drive a distributor
- Fit a spacer ring over the crankshaft nose after fitting the pulley as it's longer.

I think that's it.

Chris.
--
Series IIA 4.6 V8
R/R P38 4.6 V8

Post Reply

Return to “Engines Area”