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JJB Serenity

V8 Conversion

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Hi all,

How big a job is it swapping a 200tdi with a v8 in a 1992 Defender?

I'm pretty much a novice so need to know:

What engines are available/best to go for and are there any restrictions?

Whether the gearbox and transfer box need changing? If so, am I limited to an auto or is it possible to fit a manual?

What else needs changing (I'm guessing the fuel pump, fuel tank, fuel lines)?

Whether its worth the cost or better just to buy a truck already fitted with a V8?

Anything else I should know?

Thanks chaps, probably been covered before but when I search I just come across posts from a technical pov and I need to know some of the basics first.

And in case you are wondering why I want to do this, I've had a baby recently so may get a 110 or a Disco with a diesel for day to day driving and just use Serenity for fun.

Cheers,

JB

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Things to be changed , engine , gearbox, exhaust, engine mountings , radiator , probably seatbase, mod bulkhead , gearbox tunnel, propshafts, fuel pump, modify wiring, air filter, .

Engine is any rover V8 , inc TVR , etc . gearbox can be auto or manual, if manual 380 or LT85 . Transfer box ratio will probably require changing as well. Brakes will also need a bit of upgrading for safety . Insurance costs ? HTSH

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It's a lot of work ! For a novice it's a tall order, but not impossible.

Budget on a weeks work to do the swap as quite a bit has to come apart. All the V8 manual /auto options will fit as the componets are standard lengths without chaning the position of the transfer box and therefore the props can stay the same.

I suppose the biggest question is why you want to spoil a tidy diesel 90, if that is yours in your avatar ? If you really want a V8 then 110 V8's are cheap enough now. Original 90 V8's are rare so are expensive, but there are plenty of conversions.

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One of my friends has a VERY nice condition original v8 90 for sale, ill en-quire on price for you :ph34r:

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Cheers guys, yes sounds like a lot needs doing and I'd need help. Because I've got a kid now I can't justify two 90's and a v8 110 would be too costly to use day to day. I love my 200tdi and my truck is in great condition, the engine has years left in it I think but I really love v8's. Hmmm...

Dirtyninety, is it a station wagon?

Thanks folks

JB

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the men in white coats will be along shortly.. dont worry you will be safe soon....

on a serious note, its a lot of work, but it has been done before and everything you will need is readily available which makes it a lot easier.

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Don't let the naysayers put you off if you really want to do it! I converted my 90 from 2.25 petrol to 3.5 v8 back in 2008 and its been (mostly, until last week or so- see my pinging thread in the international forum) excellent ever since, which is great as its my everyday commuting vehicle :D

Heres my installation from 2008:

http://www.v8forum.co.uk/forum/viewtopic.php?t=4483

I would say that you need to write a list of everything you expect to have to do, then sit down and write it again. Literally walk yourself through doing the job step by step. Even changing petrol for petrol I had a lot of fiddly things to do! Also, do some reading on v8forum too for general v8 info.

I would also say don't bother with carbs - after running MS controlled ignition for some time I finally got rid of the carbs a couple of months ago- the difference is amazing!

I used a "longstick" LT77 from a Range-rover and this means that my engine sits in the factory v8 position, this means no mods to the bulkhead which is nice as it looks better and is less effort too :) Also means that factory v8 hoses etc all fit too.

Fuel wise, I have a side tank of the "two hole" type. I used a modified Range rover in tank pump PRC8318 and the separate sender. If going injection make sure you use injection rated fuel hose...

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Depending on the year, you may not need any bulkhead work - Series conversions require bulkhead work, early Defenders were V8 anyway so it fitted, dunno about later ones.

You can bolt the V8 to your existing drivetrain with a conversion plate, or swap in a V8 gearbox (but it'll need to be Defender to keep the sticks in the right place). Keep an eye on what bits are used for when you need a new clutch etc.

All sorts of scare stories about the bigger V8's but they all give a useful boost in low-down torque over a 3.5. P38 / Disco2 lumps (4.0/4.6) have better bottom ends and numerous other things (oil pump, serp belts, no dizzy, 10-bolt heads).

EFI is worth ~20% more numbers over carbs, I'd say Megasquirt'n'EDIS is the path of enlightenment for waterproofing, reliability, and MPG - buy the whole kit from Nige to save faffing.

Go electric fan, existing rad may be up to it but more is better. Oil cooler built-in is worth having but not essential (I've never run one). You may need a remote oil filter (ThinkAuto).

Apart from that, blah blah blah, have a read through the Series forum for all the discussion as it's been covered plenty before.

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Hi guys, I purchased my D90 converted to a 4.2 liter and I believe an LT77 (reverse is in the top left) I have two issues:

It is very high in torque, nice when off roading but I do not do that too often. 

It revs high when the car is stationary, if I lower in it'll turn off.

What would you do to lower the rev?

Would you consider changing the differential or a gear inside or even the gear?

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4 hours ago, moeyou said:

Hi guys, I purchased my D90 converted to a 4.2 liter and I believe an LT77 (reverse is in the top left)

Would you consider changing the differential or a gear inside or even the gear?

How many RPM is the engine doing at 70 MPH in top gear?

If the engine is doing around 2700 RPM, it will be okay. Possibly the conversion from diesel to V8 was just the engine, leaving the transfer case untouched. The diesels often have a 1,4:1 ratio in the TC. V8's manual transmission mostly run with 1,2:1, automatics a 1,003:1 ratio.

If there's no tachometer in your 90 you might have peak underneath at the TC, on the back of LT230 cases is a sticker with the ratio.

image.jpeg.945b1c144e9e680e18548cec35378fef.jpeg

Mind you, it is possible to change the ratio, fitting different gears inside. Leaving the sticker on the outside you still have no clue what's going on in there. RPM's the best way to check for proper ratio.

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You need to adjust engine idle but by the sounds of it, timing could be out. Is the vacuum line in the dizzy ok?

 

a defender v8 drives much better with a 1.4 box from my experience 

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