How to: de-ASBO my old V8

Hello all - new owner after months of reading here, almost buying a Series 3, now plumped for 1985 90 3.5 V8.
I love it but need to do all I can to quieten and smooth the running, so the home-boss will let me keep it.


Sound Q: apart from bonnet Dynamat stickers, what are all the things I can do to reduce noise?

- are there any more engine bay sound-proofing options, like the bulkhead or inner wings?
- is it worth putting a bonnet cover over the dynamat too?
It already has standard looking two mufflers on, so exhaust maybe not the route to reduce noise.
Interior already fully carpeted, so more thinking about reducing how much noise leaves the engine bay.


Running Q: apart from elec-ign and tune up, what else will improve lumpy running?

My local mechanic is doing a tune-up (really stinks like it's running rich) so hopefully he can get rid of the heavy smell that home-boss won't be able to live with, but I wondered if there are options that will make it run smoother throughout the rev range
- is the weber conversion really a cure-all as it claims?
- would I be better putting EFi on it? is there a direct bolt on e.g. from a Disco for, such an early 90, or is it more involved like swapping the head etc?


My teenage boys are the main driver - letting them get the spanners out for simple things like swapping hard top to sticks and fitting rear half door etc, but anything mechanical will end up with the mechanic, so I can't really consider options that involve weekends with the engine in bits (live in London with no garage).

I'm looking for the most cost effective way to make it drive (and smell) in a more smooth/conventional way.
I know it will always be a 40 year old V8, but every few percent quieter and smoother will help.

Grateful for any and all suggestions.

Yes they do make a bit of noise and they do smell a touch of petrol .... glorious isn't it.

Can't remember if noisekillers still in business. They were good for sound dampening. Having a small exhaust outlet presumably twin pipes to box compared to 110 V8 twins to box noise levels would be louder anyway. A very good service and good tune up with v8s is a must. Make sure exhaust manifold outlets are tight and sealed and also plenum sealed as fuel drips into the channel. As mentioned a good service and replacement of old rubber pipes and filters to the carbs. I know on the SU later on the V8 had two small metal filters from the rockers covers can be source of gunk traps.

thanks Sax - I wonder if there's a replacement kit, of pipes/filters etec for those twin SUs...

Top priority is the spectacular smell - it's bad in the car but also even for anyone nearby.
Wife can drive most vehicles but won't stick with it if we can't get rid of the heavy fumes.

What would be a list of all the perishable bits you would replace?

SNOman said:

thanks Sax - I wonder if there's a replacement kit, of pipes/filters etec for those twin SUs...

Top priority is the spectacular smell - it's bad in the car but also even for anyone nearby.
Wife can drive most vehicles but won't stick with it if we can't get rid of the heavy fumes.

What would be a list of all the perishable bits you would replace?

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Most likely from Rimmer Brothers or John Craddocks. That's where I used get my parts from when I had a 110csw 1988. Check the filters, fuel line around the carbs inlet and return pipes. As mentioned the channel or V8 valley under plenum. Lots of problems are just simple crack rubber hoses. Also the oil filled in top of the carb pots needs changing or topping up. Worth getting a parts manual downloadable from Rave.

You can't beat the sound of an eight. It should not stink of petrol once warm, has to be an issue as above. Pipe work and lift pump, carb float and seals.
If very smelly at exhaust then timing, combustion issues. If your mechanic knows Rover V8's he should be able to sort it.

tottot said:

You can't beat the sound of an eight. It should not stink of petrol once warm, has to be an issue as above. Pipe work and lift pump, carb float and seals.
If very smelly at exhaust then timing, combustion issues. If your mechanic knows Rover V8's he should be able to sort it.

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Thanks - I really hope so as it's great fun.

Are there any specific pipes to buy, or can it all just be replaced with generic fuel line?

I dropped a line to Burley to see what refurb kit they suggest too.

SNOman said:

Hello all - new owner after months of reading here, almost buying a Series 3, now plumped for 1985 90 3.5 V8.
I love it but need to do all I can to quieten and smooth the running, so the home-boss will let me keep it.


Sound Q: apart from bonnet Dynamat stickers, what are all the things I can do to reduce noise?

- are there any more engine bay sound-proofing options, like the bulkhead or inner wings?
- is it worth putting a bonnet cover over the dynamat too?
It already has standard looking two mufflers on, so exhaust maybe not the route to reduce noise.
Interior already fully carpeted, so more thinking about reducing how much noise leaves the engine bay.

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I assume you are not just meaning a V8 rumble?

In that case no. There isn’t a huge amount you can do.

Don’t get me wrong. Some sound proofing and checking all seals and panels are in good order etc can help. But ultimately it is a modular body that is bolted together then mounts metal to metal on the chassis.

Land Rover twice massively improved the refinement levels. First answer was the original Range Rover. The second attempt resulted in the original Discovery. Both are almost identical to a Defender under the body. But use 1 piece body tubs isolated from the chassis. And both massively more refined inside.

No matter what you do, you’ll never get a Defender to match their refinement levels due to the basic design and construction.

Is this a factory V8? Does it have the LT-85 gearbox? They tend to be noisy. A refurb can help, but they will always make a bit more noise.

Not saying you shouldn’t try and improve it. But checking the doors and windows shut properly will help. The full matting system over the seat box, transmission tunnel and foot wells helps too. But as said, a stock Disco 1 will easily still trump it in this regard.

I had a V8 90 CSW and it’s the one Landy I regret selling!

As for the sound, don’t try to hide it, enjoy it! A decent exhaust system will help, not a cheap pattern one. And a heavy right foot!

300bhp/ton said:

I assume you are not just meaning a V8 rumble?

In that case no. There isn’t a huge amount you can do.

Don’t get me wrong. Some sound proofing and checking all seals and panels are in good order etc can help. But ultimately it is a modular body that is bolted together then mounts metal to metal on the chassis.

Land Rover twice massively improved the refinement levels. First answer was the original Range Rover. The second attempt resulted in the original Discovery. Both are almost identical to a Defender under the body. But use 1 piece body tubs isolated from the chassis. And both massively more refined inside.

No matter what you do, you’ll never get a Defender to match their refinement levels due to the basic design and construction.

Is this a factory V8? Does it have the LT-85 gearbox? They tend to be noisy. A refurb can help, but they will always make a bit more noise.

Not saying you shouldn’t try and improve it. But checking the doors and windows shut properly will help. The full matting system over the seat box, transmission tunnel and foot wells helps too. But as said, a stock Disco 1 will easily still trump it in this regard.

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No the V8 rumble is the main reason for picking it over a diesel from that era. Plus 1985 Jan reg means it can become a historic vehicle next year (I'm inside ULEZ).
The seller says it was a factory V8 and it's on the V5, but the VIN says not, so I need to be careful about other mods, to ensure we stay inside dvla rules for historic. Hopefully swapping the hard top for sticks doesn't count towards the dvla 'chassis points' but I might keep the hard top in case - do they ever do an inspection or is it just a case of sending off the paperwork?

The carbs - likely not seen a pro mechanic for a long time, and I'm not the man to fettle an 80's V8.
It's going to a local chap recommended by a local classic car dealer as someone solid on old engines.
Seems it already has elec-ignition so hopefully it just needs a tune and replace perishable bits, but he will pressure test the cylinders etc too.

Sounds like a plan, let us know the result. Good luck.

Could I also canvas opinion on swapping the bonnet:

>> My boys want to put a later puma bonnet on - they think the bulge looks tougher but also makes the whole truck more modern.

- My original is dented and has holes to fill from chequer plate, so I'm likely going to ebay for a bonnet anyway.
- All the fancy restorations selling for a fortune seem to have done it - does that mean the look of the later bonnet is more desirable?
- On other hand, I quite fancy a bonnet mounted spare which goes well on the original bonnet...

What's the general feeling on putting the later bonnet-with-bulge on?

Bonnet is personal choice. But in my own view I’d say no. The bulge is only there as the Ford Puma diesel engine is so tall. Also don’t see why you’d want to make a classic look modern.

As for the body changes. All the answers are on the .gov site. It is very easy to read and understand.

SNOman said:

Hopefully swapping the hard top for sticks doesn't count towards the dvla 'chassis points' but I might keep the hard top in case

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The body style should not alter the vehicle status as only the chassis is structural/linked to the vehicle ID. I swapped my sereis III from a hardtop to a soft top.

SNOman said:

My boys want to put a later puma bonnet on

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Your boys need to look in the mirror and have some stern words with themselves!

SNOman said:

they think the bulge looks tougher but also makes the whole truck more modern.

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Definity does not look tougher, makes it look more modern and therefore not as good as the old ones, it is a classic vehicle embrace that rather than trying to make it something its not. It also makes it look more like a pavement process, might as well fit alloy wheels and a metallic paint job while you are at it! Do you think a bonnet bulge would make mine look "tougher", I beg to differ:

SNOman said:

My original is dented and has holes to fill from chequer plate

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I know it divides the room a little but if you already have the holes for chequer plate I would fit chequer plate back to it. It allows you to stand on the bonnet to access the roof (same as the wing tops) and although not original was fitted to so many vehicles it is not an issue unless it is fitted to side panels to hide corrosion. I would hoever advocate for painting chequer rather than leaving ti silver. Mine is black but colour is up to you, have seen body matched look quite effective on older vehicles. but painting eliminates the glare and reflection form silver ali.

SNOman said:

All the fancy restorations selling for a fortune seem to have done it - does that mean the look of the later bonnet is more desirable?

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Because all of the "fancy" restorations are targeted very specifically at the Chelsea tractor brigade rather than the classis car market and their desirable characteristic is to make it looks as new and shiny as possible (see my above comment about a pavement princess). Currently in this faction a defender is the trendy must have accessory but in a few years when it is out of fashion these restoration will be difficult to sell and not valued as they are not original and difficult to return to original.

SNOman said:

On other hand, I quite fancy a bonnet mounted spare which goes well on the original bonnet...

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I like a bonnet mounted spare and have one on my series but they are a long way form practical. they significantly reduce visibility even with the original 7.50 tyres, as soon as you put larger modern tyres on it is even worse. It makes lifting the bonnet very heavy and also makes it difficult to remove the spare when needed. It is personal choice but is not really a practical option for every day driving.

I’d either keep the original bonnet as above or replace with the same. The bulging bonnet does nothing to enhance a Landy in my opinion. However, it’s your Landy so go with what suits. Just be wary of where you buy a puma bonnet. There are lots of puma defenders being stolen so make sure you don’t buy a stolen one…

If the v8 is noisy then an overhaul will do wonders. New timing set, new camshaft. Check the rockers and lifters for wear and operation.
If it's smelly while driving then you have an exhaust leak somewhere. Doesn't have to be much

Knappster said:

I’d either keep the original bonnet as above or replace with the same. The bulging bonnet does nothing to enhance a Landy in my opinion. However, it’s your Landy so go with what suits. Just be wary of where you buy a puma bonnet. There are lots of puma defenders being stolen so make sure you don’t buy a stolen one…

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Indeed and if you do buy one make sure you keep the old bonnet to replace yours when it gets stolen.
Infact make sure you fit a pedal lock, steering lock, alarm, immobiliser while you are at it.

SNOman said:

>> My boys want to put a later puma bonnet on - they think the bulge looks tougher but also makes the whole truck more modern.
<snip>

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It's a worrying sign.
Later in life they will be swayed by girls with breast augmentation, brow lifts and large botox bills.
Later on, as a defence mechanism for making the initial choice in their formulating years, they may dye their hair and desire a 'man bun' along with requesting beard wax for christmas.
They will likely reach a point where Gynecomastia surgery is seroiusly considered.

You can stop all this .... say no to a bonnet bulge.

Haha - brilliant. I guess we're only a few miles from Chelsea, but a very different budget
Looks like I'll get to keep the old bonnet - maybe add a spare-carrier later, when I've replaced the huge tyres with more standard.

Is it difficult to straighten the old ally bonnets?

I heard it's harder for a panel beater to get straight lines again, but I don't want to use filler.
Currently has a strange metallic silver covering the original slate grey, so we'll paint it eventually anyway.

Depends how badly dented it is. I’d have thought it should be fairly easy to straighten. Not that it’s hard to find a used one.

The Puma ones are a lot heavier, I think they are steel skinned.