Your V8 conversion ?

[Not_Anumber]

Has anyone on here carried out a V8 conversion ?

Someone gave me a Rover V8 SD1 engine and a gearbox a few years ago that have been languishing in a shed waiting for time, knowledge and enthusiasm to catch up.

Ive read through the usual books but still not clear on some aspects, particularly whether there is a need to enlarge the transmission tunnel on a late RB BGT or if that mod was only necessary for earlier cars.

[Not_Anumber]

Anyone heard from Bumpa ? Im conscious he has done a V8 conversion so it would be good to hear from him and gain from his experience.

[Bumpa]

Chris, I did a conversion on my 1969 GT, finishing it in 2009. It has had a reasonable use since then and has covered about 38,000 miles with complete reliability, including a trip to southern France, trips from Scotland to the south of England, and tours round much of Scotland where we live.

Mine has the 3.9 litre engine from a 1991 Range Rover complete with hot-wire fuel injection, linked to the Rover R380 5-speed gearbox. This connects to an independent rear suspension from Hoyle Engineering with a Ford Sierra 3.14 diff with Sierra drive shafts and rear disc brakes. The front suspension is also from Hoyle and features large ventilated 4-pot brakes. I have also installed electric power steering.

Because it is a chrome bumper car I had to alter the corners of the bulkhead (firewall) to make room for the rocker box covers, alter the engine mounts to the rubber bumper type, move the radiator right into the nose as per the later cars, cut holes in the inner wings for the exhaust manifolds (headers), and I did raise the height of the transmission tunnel, although I'm not certain that was strictly necessary. The gear lever has a dog-leg welded into it below the floor to bring it up in the correct place.

Ask your specific queries and I will do my best to answer them. I used Roger Williams' book extensively during the rebuild.

Mike

[Not_Anumber]

Mike, many thanks for this. You have certainly gone to town on yours with Hoyle's suspension conversions. Looking at their site I spotted one of the owners is Gerry Hawkridge; I built one of Gerry's Hawk AC Ace replicas in the 1990s - B front and rear suspension, TR6 engine with a ported and polished head that gave some of the Cobra replicas a run for their money on a fake snake track day. at Goodwood Then family life intervened, i digress.

Im planning to do my conversion in running stages; engine, gearbox & brakes first, then run the car for a while before adding the suspension upgrades.

So, to plan the first step and start sourcing parts:

In your opinion is it worth me building up the 3.5 SD1 engine I have sitting here and then have to think about induction - or just best to buy a running 3.9 with it's donor fuel injection ? If so is it generally thought best to buy and strip a damaged donor Range Rover/ Discovery or just buy the removed engine ?

Theres a R380 gearbox on Ebay currently from a V8 LDV 400. Roger Williams' book mentions van LT77/ R380 gearboxes usually arent suitable as they have the wrong ratios but Im not clear if he meant just to avoid those sourced from the normal diesel and small petrol engined vans and that perhaps the ones used in the rarer V8 vans would have the right ratios for car use. Any thoughts that would set me on the right initial path would be very welcome.

For your steering did you cut the column and use a Nissan/ Fiat electric steering unit or did you utilise a power steering rack from a different vehicle running an electric steering pump ?

Chris

[Bumpa]

Mike, many thanks for this. You have certainly gone to town on yours with Hoyle's suspension conversions. Looking at their site I spotted one of the owners is Gerry Hawkridge; I built one of Gerry's Hawk AC Ace replicas in the 1990s - B front and rear suspension, TR6 engine with a ported and polished head that gave some of the Cobra replicas a run for their money on a fake snake track day. at Goodwood Then family life intervened, i digress.

Im planning to do my conversion in running stages; engine, gearbox & brakes first, then run the car for a while before adding the suspension upgrades.

So, to plan the first step and start sourcing parts:

In your opinion is it worth me building up the 3.5 SD1 engine I have sitting here and then have to think about induction - or just best to buy a running 3.9 with it's donor fuel injection ? If so is it generally thought best to buy and strip a damaged donor Range Rover/ Discovery or just buy the removed engine ?

Theres a R380 gearbox on Ebay currently from a V8 LDV 400. Roger Williams' book mentions van LT77/ R380 gearboxes usually arent suitable as they have the wrong ratios but Im not clear if he meant just to avoid those sourced from the normal diesel and small petrol engined vans and that perhaps the ones used in the rarer V8 vans would have the right ratios for car use. Any thoughts that would set me on the right initial path would be very welcome.

For your steering did you cut the column and use a Nissan/ Fiat electric steering unit or did you utilise a power steering rack from a different vehicle running an electric steering pump ?

Chris

Let's have a go at your questions Chris.
A 3.5 engine can be upgraded to a 3.9 by changing the cylinder liners. Whether that's worth doing I don't know. I looked on ebay and found a guy in Huddersfield who was dismantling a 1991 Range Rover. He advertised the complete engine, fuel injection and associated wiring harness with a starting bid of £500 (back in 2004 probably). I put in a bid up to £750, but was the only bidder so got it for £500. The seller was quite disappointed! You must have the associated harness, ECU and other relevant parts as these would be very difficult to replicate.

The wiring turned out to be pretty simple. I mounted the ECU in a fabricated tray under the left side of the dash and found the harness was exactly the right length to go from there into the engine bay to reach all the sensors and injectors. There are only four wires that need to be connected to the car's harness in it's simplest form. The Range Rover mine came from was an automatic, but that didn't matter, and I changed the tune resistor so it wouldn't go looking for a lambda sensor signal as I haven't fitted catalysts.

Ideally you need a speed sensor, although it does work without one but will always be in a default mode rather than learning the best settings for your car. Since I have used electronic instruments from Speedy Cables I already had installed a speed sensor fed by a standard speedo cable. I then had the pleasure of adjusting the speedo to correspond to my sat nav, so it is now dead accurate.

I originally had an LT77 gearbox from an SD1, but when the car was running I found it made a horrible whining noise. I found a bloke in Birmingham (can't recall his details at the moment - it was over 10 years ago) who rebuilt Rover boxes and he offered me a reconditioned R380 from a two-wheel drive application. I've no idea which vehicle it started life in. The lower ratios aren't ideal. First gear is too low and I rarely use it except for traffic crawling or starting on a steep hill. The change from first to second is slow and a bit clunky, but you will find that most users of these boxes says the same thing. The engine has bucket loads of torque so pulling away in second is no trouble at all. The gap between second and third is a bit wide in my opinion, but 3, 4 and 5 are fine and that's where I spend most of the driving time.

You will definitely want to change the rear axle ratio. 3.91 is much too low for an engine that isn't known for it's ability to rev. I hardly ever go above 4000 rpm. Why would you when it pulls so strongly in higher ratios. For a live axle the MGC unit at 3.31 isn't too bad but try to find one! The best is the V8 axle with a 3.07 ratio. I believe you can now get new 3.07 crown wheel and pinion sets to fit into your axle case. With the Hoyle suspension comes a Ford Sierra or Granada diff and mine is the highest available at 3.14. Obviously you need a replacement prop shaft to connect the Rover gearbox to any of these diffs.

I drove without PAS for a number of years, but with 195/60 x 15 tyres it was heavy for parking. I bought the expensive electric PAS from EZ (http://www.ezpowersteering.nl/23/Home.html). They send you a brand new upper column with the motor attached, plus all the electrics needed to work it. I installed it myself which wasn't difficult with phone help from their UK representative. The motor sits behind the centre console and is barely noticeable visually. It has transformed the car and parking is now a breeze. On the motorway at speed I suppose I could say that it is perhaps a bit too light, but that's being picky. Mine only registers the effort put into the steering wheel. The more effort you need, the more it helps, so at speed it hardly operates at all. They now make a speed sensitive model which would be an improvement. By the way, I first tried the castor reduction wedges that you often see advertised. For me they made no discernable difference and I ditched them when I fitted the PAS.

I hope that helps. Ask away.

Mike

[Bumpa]

A couple of other things. The hot-wire fuel injection kit is too tall for the MGB bonnet. I used a new RV8 bonnet but still had to shave about 16mm off the trumpet base and trumpets to get 5mm clearance. It all depends how high your engine mountings are fitted. If yours is a rubber bumper car it has the correct mountings and should be OK. Mine is a chrome car and I must have welded the new mountings on a bit higher than standard.

Oh, and it was Hartlepool, not Huddersfield! I went down with a trailer and found the vendor on a farm. He lifted the engine onto the trailer with a fork lift.

[Not_Anumber]

Many thanks that is a superb description. Did you need to replace the engine front timing cover and pulleys to provide sufficient clearance against the rack ?

What is the hot wire system you mentioned im relation to induction and bonnet clearance. Is this part of the donor car's injection system or an aftermarket unit please ?

[Bumpa]

Many thanks that is a superb description. Did you need to replace the engine front timing cover and pulleys to provide sufficient clearance against the rack ?

What is the hot wire system you mentioned im relation to induction and bonnet clearance. Is this part of the donor car's injection system or an aftermarket unit please ?

I didn't replace the front timing cover but kept the Range Rover one which has a better water pump. I did have to shave the boss off the front of the water pump pulley but otherwise it fitted between the engine and rad OK. It did mean that the alternator was bit further forward and the edge of it's fan blades just pinged the bonnet lid. Cutting 3mm off each blade sorted that! In retrospect I could have welded the engine mounts a fraction lower which would have made the job easier.

The Lucas 14CUX hot-wire fuel injection is a very simple EFi system fitted as standard to the classic Range Rover from 1990 on. see here: https://en.wikipedia.org/wiki/Lucas_14CUX

[Not_Anumber]

Thanks Mike. A Range Rover sourced engine does seem to be the best way to go all round, using the SD1 engine I have would need a change of timing cover and pulleys according to the book.