How/where would you get an engine built ?

[simonbuk]

Purely out of interest how/where would you get a new engine built, future proofng it for some more power ?

As far as I'm aware there aren't any specialists to go to discuss an engind build.

You can't buy a new head or crank ? Cams ? Thought I read somewhere on here that the cranks have some special coating on them and once damaged can't be repaired ? As you can't buy them new what would you do ?

Just thinking that if my premium bond numbers came up, how to spend it ?!

[Fredjohn]

Simon
I think crankshafts are still available: provided they are the same as the 1991 Isuzu Impulse 1.6 turbo, then Rock Auto can supply and it includes the main bearings.

But I know nothing about Isuzu in detail: it may have been modified for the Elan application Or again it may not.....

Pistons (std and o/s), rings and main bearings are all listed and priced on SJ Sports Cars' website. Does that = available?

As for rebuild, you would need to talk to one of the Lotus specialists like SJ or Paul Matty or the many others (!) to see who they use/recommend.

Having said that I am sure someone will be on here in due course to further illuminate your musings..

[lotustonybassplayer]

SIMON IF YOU DO A SEARCH FOR FAVERSHAM. ESM HAD HIS ENGINE REBUILT AT A SHOP THERE

[simonbuk]

Yes, this is the thread. Interesting and not too bad at 2K I guess ? This would be to build it back to standard of course.

viewtopic.php?f=80&t=20542&p=261436&hilit=Faversham&sid=57191d8890ffd97eaf51f10b4bf675d0#p261436

[Brit-Car-Nut]

I am NOT trying to discourage anyone, BUT, I have been helping a friend locate the parts needed to do a rebuild - and as of now, there are no pistons, rings or bearings available in any sizes from Lotus.

They are all active numbers in the current price book, but stock is gone and apparently not available from Isuzu. Checking with SJ Sportscars gives the same answer. No Longer Available. They have them listed because Lotus has them listed.

Most suppliers like Rock Auto don't understand the Turbo has a forged crankshaft, con rods and pistons while the NA had cast parts and what you will get is a cast crank if you buy from them. Same with the pistons on rock and on the sellers on eBay. Rings are the same between the models, so they can be purchased from several decent suppliers. Con Rods are currently on the Special offer list at Lotus, so if you think you will need them in the future, grab now.

Turbo Camshafts are obsolete although the NA ones are still listed with a price.

Robbie C. Blair's "RobbieTheRobot.com" website still lists ROSS custom Forged Piston Assemblies but he doesn't answer emails or take phone calls.

I called Ross directly and they will still make pistons to order but the price will be higher than what is quoted on Robbie's site unless you are prepared to buy 5 sets or more.

The lesson here is DON'T hurt your engine! Overheating is a real disaster as it will cause all of the parts to twist, stretch or shrink which will cause horrible tolerances and you will end up with collapsed pistons, scratched bores and warped heads.

Standard bearings and rings can be purchased and Lotus still has the correct gaskets for the Turbo engine, but that may change without notice any day.

If you want a FRESH engine, rebuild it BEFORE damage or wear cause the dimensions to be out of specification. The chances of finding a rebuildable core at a breaker is enormously low and you will probably find that what you scrounge is as bad as what you already have.

[simonbuk]

Wow - sounds like turbo engined cars (ie most!) will be in trouble in the future - if not now.

We'll all be rebuilding to n/a spec !!

What was I thinking about that crankshaft coating or was I imagining it ?

[simonbuk]

Theres these pistons available but they seem bloody expensive !!

http://www.ebay.co.uk/itm/LOTUS-ELAN-M1 ... MAEXnIuNmA

[Brit-Car-Nut]

Crankshafts are usually CAST, Forged, Nitrited or Tuftrited.

Nitriting and tuftriting are "coating" processes but mostly now banned due to the chemicals needed to do the work.

Repaired crankshafts can not be "coated" .

The NA Crank is the same part number as the Turbo, so finding a NA core might be helpful since they are less likely to be "slap worn out", but the block will need some parts transferred like the piston cooling oil jets.

The NA head is the same casting as the Turbo but will require that you use the Turbo head gasket.

[Brit-Car-Nut]

Theres these pistons available but they seem bloody expensive !!

http://www.ebay.co.uk/itm/LOTUS-ELAN-M1 ... MAEXnIuNmA

BTW, the listing is for .5 and 1.0 oversize, not standard 80.00mm bore.

Pistons (even Standard Size) from Lotus were more expensive than those when you added the "not included" rings, grudgeon pins and locks

[dapinky]

Here's my 2p worth on this.....

..... as others have said, beware of ANY replacement crankshaft - the Lotus one you already have is forged and toughened/coated after the bearings are polished to size. Some (good) engine builders will be able to machine them down a size and get them recoated (which isn't a coating, but you know what I mean!) - but unless you have had a major disaster, you won't ever need to do it.

I am yet to see a crank which is damaged beyond reuse (but I'm sure it WILL have happened somewhere) - usually, just a set of new standard-size bearing shells is all you will need. Again, as well as the usual suspects for getting them, any engine builder will be able to buy them - they aren't always model-specific - and they aren't always very dear.
(I paid about £45 for both main and big end shells).

I was lucky in that I got into a 'group buy' on Isuzone forum for a set of forged pistons at a slight oversize - they came from USA and were made by the same company that Robbie the robot uses (and also Phil at SW Lotus, that the ebay link is to). Whilst I got them at a 'group' rate, even getting one set machined in USA was cheaper than SWL (obviously, as they need to make a profit) - and at the time, the $/£ rate was more favourable to us in the UK. I think they came in at £450ish including all shipping, duty, VAT etc - with rings and gudgen pins/clips.

I wanted oversize, but again, unless you've had a disaster, usually it will get away with the OE pistons, new rings and a bore hone.

As for cams - they don't seem to wear too much (again I got a pair many years ago from Lotus aftersales for a stupid price of £2 each because no-one ever needed to buy them).

The cam followers are Isuzu parts, but NOT for the Impulse 1.6 (can't confirm, but common belief is that they were from the 1.8 engine) - I'm sure they wouldn't be hard to source if needed (but probably NOT needed).

If you have a good engine at the moment, but want to future-proof it a bit before it suffers major wear/failure - you may well just need a set of crank shells, piston rings and some work on the valve seats/guides/seals.

I am just collecting the parts together for the day of major failure whilst they are/were available, but i have a spare engine with 130K miles on it that I will re-build with all these bits, swap them over, then refresh the one in the car with (hopefully) just shells and rings. It's a job I've been planning for a number of years, and will get done when I get round to it.

As for the machining, there is a company in Bristol who i have used for many years (Price Brothers at Avonmouth) - I will give them the block/crank and the parts, and let them do the bore machining and fit the bits together for me, so I just have to do the head and rebuild it.

[Brit-Car-Nut]

Dave, I agree completely except that I have been collecting parts for a while and I have 6 or 7 engines currently and a couple of them have spun cranks, cams and horrible scoring in the bores. I didn't pay a lot for them and there are some other parts to scrounge, but I have seen some really screwed up engines. I also have the brand new engine that was on the podium (in the open chassis) during the introduction of the M100 in 1989/1990. I am STILL not sure it is a Turbo or NA. There is a turbo bolted to it but it isn't brand new. It could be a test turbo and the engine could be a Turbo model but I have yet to find an engine number on the block. It does have the Lotus logo on the valve cover.

I also have one of the "mule" test engines from the "drive around" testing done in the late '1980s and early 1990s. It is basically an Isuzu Turbo (the valve cover doesn't say Lotus and there are numerous external temp sensors all around as well as a fuel pressure regulator with a gauge port. It appears to be custom made and I have never seen another one in all of my searching for obscure and interchange parts.

I also have a couple of Crank Kits from a major supplier that are what they listed for the Impulse Turbo but inside the boxes are CAST cranks. You can't trust a crank re-grinder to know the difference between NA and Turbo.

Oil pumps are another conundrum: it appears that the NA and Turbo use different pumps but the only thing different in the break-down is the spring for the relief valve.

[simonbuk]

This ones out of curiosity - I know that Isuzu are a Japanese arm of GM. The engine looks very similar to a Vauxhall engine of the 90's so must have some DNA in there ? If so the dimensions should be similar ?

[lotusflasherman]

Purely out of interest how/where would you get a new engine built, future proofing it for some more power ?

Here's my 1p worth...

On turbo engines 'engine rebuilding' and 'more power' are not necessarily related. More power, in some quantity, can be obtained by simple changes to the induction system - EMU chips to run higher boost on existing turbos, bigger turbos to run even more boost with their own engine management system and different exhaust systems to get the gas away. Obviously not something to do on a high mileage, half-knackered engine or it may soon be completely knackered, but OK on low mileage or recently rebuilt engines.

On the rebuild side ...not a lot to be gained by 'blueprinting the engine' or flowing oil and waterways to reduce internal losses, and overbore piston sizes are a 'service option' allowing a block to be rebored for further use. There is such a nominal increase in capacity, a couple of % at most, that power increase will not be significant.

There is a thread here about installing the 1.8 engine, which will make a difference, but it started in 2012, stalled, restarted for a few months in early 2016 and nothing heard for almost a year. 4XF1 project.

[dapinky]

John,

I don't doubt that many engines could be damaged - I am probably lucky in that i have only found/worked on ones from fairly well looked after Elans.... And agree that you can't trust some people to know the subtle (or not-so-subtle) differences between turbo & NA bits.

As an aside, do you know of any current listings for the oil pumps? - when i last researched it all (probably a year or more ago), and we ascertained that the difference was in the relief spring, everyone who I found stated that the item wasn't in stock...... and I failed to follow it up as I wasn't in any desperate need.

[Brit-Car-Nut]

Like you, I stopped looking but a pump will be needed for my friend's rebuild so I will again start the search and report my findings.

[clemo]

The crank on an N/A is made of cheese .
My bottom end went and the engine shop Re worked it . They went below tolerance and hey presto i needed another engine rebuild.
We had all the literature required but it just didn't work .
Even back then an NA crank was as rare as hens teeth . Luckily Paul matty had a new one on his shelf.
I did see one in a lotus aftersale a few years back .
The top end was redone with rock autos parts . all the photos went with the car when i sold it . Cost me over £2000 back in 1999.

[Scott]

Hello.. I have done an engine rebuilt last year which with parts and labour cost me 2.500 euro. I have been using as many OEM as I could find and then I used aftermarket. Anyway, you can upgrade to larger forged pistons ours are 80.5 and you can get 81mm or 81.5 I think. That increases the pressure in the engine so you can get more power. But for me, there is no reason to buy that pistons if you're not drag racing. Elan were designed to run daily and race at the weekends and not been buzzy Fiat Uno's. Try to understand that you can easily upgrade the car by increasing turbo boost through Everest chips and getting a larger stainless steel exhaust. You can get your car 220-240 bhp and it will be veeeery enough. In the end Elan's ability is cornering and not drag racing. Enjoy your car withing a circuit.
In the end you only got 1.6 liters but bulletproof Japanese engine. You cant go less than 5.5s 0-60m

[lotusflasherman]

... you can upgrade to larger forged pistons ours are 80.5 and you can get 81mm or 81.5 I think. That increases the pressure in the engine so you can get more power.

Disagree with that bit ..Going from 80.5 to 81.5 increases the piston area by only 2.5% so small increase in power BUT you've used up all the future re-bore allowances. Any wear on those bores and you'll be searching for a new block ... not really 'future proofing'. If a rebore is needed because they are oval or barrel shaped it's best to go to 81.0, if possible, leaving the 81.5 for the future.

Agree with the rest as it's sort of what I said earlier .... Boost is King .. concentrate on induction and exhaust improvements ...

[Brit-Car-Nut]

Since forged pistons are NOT available from any normal source, it would be helpful if you posted where you found some.

2.500 euro was/is a LOT of money for an engine rebuild but a fair amount of that was for labor. Did that include removing and reinstalling the engine or was it just for the machinist's part of the job?

There are a LOT of Chinese suppliers showing listings for replacement pistons for the Turbo Impulse, but their pistons are CAST, not FORGED. Are you really sure you got FORGED pistons?

Also, the Standard Bore is 80.0mm not 80.5mm and anything up to 80.030mm is considered Standard. Isuzu/Lotus do not recommend or offer pistons above 81mm as cylinder sleeve thickness is a concern.

Currently, only one company is offering custom FORGED pistons and they cost almost $250.00 EACH!!!! BEFORE shipping and handling.

Engine Bearings are also a huge issue. Since the Forged Crankshafts were very hard to keep absolutely the same size, there were odd oversized bearings that could be purchased to compensate for an odd sized journal. I believe all of the special Isuzu bearings are now obsolete from Lotus AND Isuzu.

Any grinding or even polishing of the crankshaft will remove all or at least some of the coating, thus the special bearing assortment.

The cost of all of the normal parts to rebuild the engine using Isuzu or Lotus parts far exceeds the 2.500 euro you said you paid for the entire rebuild, so it would be helpful if you could show what was actually replaced vs reused.

[lotusflasherman]

You're right BCN! Bore is 80mm nominal, with + 0.5 mm & +1.0 mm overbore available. Just took Scott's numbers but still don't know where the 81.5 came from.

To rebuild an engine doing all the cleaning down and proper checks (e.g. Plastigauge) as you rebuild is quite time consuming so if you are not doing it yourself you can expect a big labour bill.
If it's not big, it's probably just been bolted together without checking anything. Might be fine ... but might not .