Engine rebuild

Engine rebuild

Author
Discussion

Never you mind

1,399 posts

56 months

Wednesday 12th December 2018
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4321go said:
I used ceramic coated bypass pipes supplied by BHP. Pretty easy to fit and retain the original lambda sensors. About 16,000 miles now and no issues with spurious engine warning lights. I already had an OEM Superleggera exhaust fitted (brand new and £155 on eBay from a scrap metal merchant who didn’t really know what he was selling; thankfully, all the rest f you missed it!!). Decatted, the noise is ABSOLUTELY EPIC (feel free to comment, Lambodave!). And it shoots blue flames that you can actually see in the rear view mirror at night!!!

MoT? Yes, you need cats to pass........
Flames you say... woohoo

Mines done 18K and just out of warranty so a decat sounds like a good way to go but is it a bit droney at motorway speeds?




Krikkit

15,702 posts

125 months

Wednesday 12th December 2018
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The decat pipe should make minimal difference to the sound at constant revs if properly sized - the error is often that they get replaced with hollowed-out sections that look like OEM cats which just act like a huge resonator, presumably to maintain the fantasy of still having a cat, rather than putting a bit of straight pipe in.


4321go

Original Poster:

480 posts

131 months

Wednesday 12th December 2018
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Nope, they’re proper bypass pipes; a constant diameter from headers to silencers.

As for “little or no difference” to the sound? The various stages from standard to SL back boxes to SL + decat went from boring to loud to EPIC. If you haven’t looked down a catalytic converter before, then you’ll be amazed at just how much material they contain. I’d say that at each stage the volume doubled. And the timbre is soooooo much better! Somebody commented recently that when they were following me, they turned off their radio for the entire trip (30 miles or so) just to listen to my exhaust note. It’s that addictive!

I’m in my late forties and commute 55 miles each way, both early in the morning and late at night. I don’t necessarily want LOUD and certainly don’t want a drone. I was a little worried that at each stage it’d be more than I could live with, and certainly, when I first heard it post-decat I wondered if it was too much. That lasted about a week.

But you can still hear the radio, albeit turned up a couple of notches, and you can still hold a conversation, with a ditto re volume. It’s close to open pipes and liveable-with on the day to day commute. As for the top of the rev range!! Wouldn’t swap back for all the tea in China.

IMI A

6,792 posts

145 months

Wednesday 12th December 2018
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Brill thread. Is there any scope to upgrade these engines a bit when rebuilding?

4321go

Original Poster:

480 posts

131 months

Wednesday 12th December 2018
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Yes. Anywhere from stock 500bhp to twin-turbo 1500bhp. It’ll be returning to everyday road duties, so the latter is impractical and pointless. And if Ricky rebuilds the engine to absolute bog-stock OE and only achieves the former, I suspect that he’ll be deeply upset with himself!! But I doubt that it’ll end up completely bog-stock.....

Watch this space.

IMI A

6,792 posts

145 months

Wednesday 12th December 2018
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Subscribed! wink

Krikkit

15,702 posts

125 months

Wednesday 12th December 2018
quotequote all
4321go said:
Nope, they’re proper bypass pipes; a constant diameter from headers to silencers.

As for “little or no difference” to the sound? The various stages from standard to SL back boxes to SL + decat went from boring to loud to EPIC. If you haven’t looked down a catalytic converter before, then you’ll be amazed at just how much material they contain. I’d say that at each stage the volume doubled. And the timbre is soooooo much better! Somebody commented recently that when they were following me, they turned off their radio for the entire trip (30 miles or so) just to listen to my exhaust note. It’s that addictive!

I’m in my late forties and commute 55 miles each way, both early in the morning and late at night. I don’t necessarily want LOUD and certainly don’t want a drone. I was a little worried that at each stage it’d be more than I could live with, and certainly, when I first heard it post-decat I wondered if it was too much. That lasted about a week.

But you can still hear the radio, albeit turned up a couple of notches, and you can still hold a conversation, with a ditto re volume. It’s close to open pipes and liveable-with on the day to day commute. As for the top of the rev range!! Wouldn’t swap back for all the tea in China.
Sorry, when I meant no change I meant it shouldn't be boomy at particular revs etc. There should just be more noise with pops and bangs etc where the cats haven't removed it. smile

br d

7,084 posts

170 months

Wednesday 12th December 2018
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Brilliant thread. And I've always loved your plate.

I normally put about 7K a year on a supercar and thought that was using it properly, you sir are a legend!

4321go

Original Poster:

480 posts

131 months

Wednesday 12th December 2018
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br d said:
Brilliant thread. And I've always loved your plate.

I normally put about 7K a year on a supercar and thought that was using it properly, you sir are a legend!
Thank you, but.....

I got lucky with the plate. Many years ago now, I saw it advertised in one of the weekend broadsheet’s motoring supplements and made a cheeky offer. I paid less for it than the original purchaser had paid the DVLA for it at auction!

And given that the average UK driver covers 8000 miles per annum, 7000 miles in what’s probably a second (or third) car seems like pretty proper usage to me!

Spindoctor

532 posts

144 months

Wednesday 12th December 2018
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Most interesting and useful thread in this neck of the woods for a long time, thanks for doing it. My Gallardo is only in its early 30s mileage-wise and has averaged just a couple of thousand a year in my 5 years of ownership (love driving it, lack of time).

Do you re-fit the cats when its MoT time? Or is it best not to ask...?

I remember someone on here once saying these cars start to fall apart after 30k miles. Hope they've tuned in to this thread.

200Plus Club

6,531 posts

222 months

Wednesday 12th December 2018
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Spindoctor said:
Most interesting and useful thread in this neck of the woods for a long time, thanks for doing it. My Gallardo is only in its early 30s mileage-wise and has averaged just a couple of thousand a year in my 5 years of ownership (love driving it, lack of time).

Do you re-fit the cats when its MoT time? Or is it best not to ask...?

I remember someone on here once saying these cars start to fall apart after 30k miles. Hope they've tuned in to this thread.
Brand new sports cats and perhaps replace them at every 50k miles as an insurance policy if you are keeping it would be my suggestion.
Not sure of lifespan of most cats but some I removed were turning to dust when knocked about on a track day car I had. They had 95k mikes on them and were very brittle and loose in the casing

hyphen

10,282 posts

34 months

Wednesday 12th December 2018
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GG33 said:
Looking forward to future posts on this thread..

GG
+1

Great thread OP, and respect for putting on the miles daily.

LamboDave

39 posts

70 months

Wednesday 12th December 2018
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Just to confirm the decat and exhaust combo on the car in question sounds incredible. There is no noise I’ve heard a car make that comes close to the sound of that V10. Addictive is the word I’d use. I’m looking forward to the results of the rebuild as much as the OP.

Dr G

13,735 posts

186 months

Thursday 13th December 2018
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I can't add anything more than saying I'll follow with interest; have only heard good things about RE performance.

4321go

Original Poster:

480 posts

131 months

Thursday 13th December 2018
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LamboDave said:
Just to confirm the decat and exhaust combo on the car in question sounds incredible. There is no noise I’ve heard a car make that comes close to the sound of that V10. Addictive is the word I’d use. I’m looking forward to the results of the rebuild as much as the OP.
I didn’t decat my car with the intention of making it louder; I did it in the hope of eaking-out a few thousand more miles from an engine that I knew would need rebuilding eventually. And I can claim no responsibility for engineering the resulting exhaust system. What has resulted has been a lucky outcome! The combination of the harder-edged sound of the 5 litre engine, the Mk1 Superleggera silencers and the cat bypass pipes just happenes to produce an exhaust noe that I think is awesome.

LamboDave WAS responsible for engineering some of it (at least for managing to fit the SL exhaust to the standard coupe frame; in great Italian supercar tradition, it wasn’t a straight swap-over!!) He also advised me that I might find the decatted car TOO loud. We were both surprised with the results!!

Without removing his superhero mask, LamboDave (who’s real name may or may not be Dave biggrin ) has driven several Lambos every working day for the last 15 years, so if he too thinks that it sounds increadible..............

Cheers (may-or-may-not-be) Dave!

Edited by 4321go on Thursday 13th December 17:40

Superleg48

691 posts

77 months

Thursday 13th December 2018
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Mine is an SL2 with an OEM Super Trofeo Exhaust fitted. It has about 18,500 miles or so. I would like to learn more about decatting, including MOT implications / work arounds. Who can I PM to discuss further options etc...or would be happy to discuss on this thread or start a fresh thread. I don’t want to derail 4321Go’s engine rebuild thread.

Or is it something I need not worry about just yet in terms of risk?

It is not really sound Improvements I am looking for, since the ST Exhaust is already fairly epic more preserving the engine from the risks highlighted earlier.

LamboDave

39 posts

70 months

Thursday 13th December 2018
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I wouldn’t worry about it on the later LP spec engines, the catalysts are completely different from the early type. I’m also sure they are integrated into the manifolds so not such an easy swap. Unless you have a running issue which causes the catalysts to overheat, they shouldn’t fail.

todea20

122 posts

77 months

Friday 14th December 2018
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LamboDave said:
I wouldn’t worry about it on the later LP spec engines, the catalysts are completely different from the early type. I’m also sure they are integrated into the manifolds so not such an easy swap. Unless you have a running issue which causes the catalysts to overheat, they shouldn’t fail.
Mine is a 2009 Lp so i shouldn;t be worried about this problem? Coming now to 15k miles

LamboDave

39 posts

70 months

Friday 14th December 2018
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As stated on this thread and many others, the Gallardo and Murcielago have been known to suffer from catalyst break up in rare cases. As far as I am aware and from personal experience, I have not heard of or seen a failure on an LP series engine. If I was lucky enough to own one I would not be worried about changing out the catalysts especially at low mileages.

ElanS

52 posts

15 months

Friday 14th December 2018
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LamboDave said:
As stated on this thread and many others, the Gallardo and Murcielago have been known to suffer from catalyst break up in rare cases. As far as I am aware and from personal experience, I have not heard of or seen a failure on an LP series engine. If I was lucky enough to own one I would not be worried about changing out the catalysts especially at low mileages.
That's good to know. I was thinking of decatting my LP560 with 23k miles but I think I will hold off until later.

I would be happy if I managed to do half the mileage the OP has, well done!