Engine rebuild

Engine rebuild

Author
Discussion

4321go

Original Poster:

480 posts

131 months

Monday 18th February
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mike01606 said:
The cats are actually quite close to the engine. Valve overlap and exhaust tuning cause pressure waves in the exhaust system... particles can 'ride' these waves back into the cylinders.
I wrote above that I’m a one finger typist. You wrote that in the half-hour or so it took me to write and tweak my later reply wink

mike01606

495 posts

93 months

Monday 18th February
quotequote all
4321go said:
I wrote above that I’m a one finger typist. You wrote that in the half-hour or so it took me to write and tweak my later reply wink
A great thread and if you need to borrow any extra fingers and toes to add it all up at the end (as you'll definitely need more than one) give me a shout laugh

It's come to me now 'reversion waves' is the phrase I was trying to think of....

4321go

Original Poster:

480 posts

131 months

Monday 18th February
quotequote all
“Mmmmmmmm....... Complicated.........” (best said à la Homer Simpson):

http://www.formula1-dictionary.net/exhaust_road_pe...

The Surveyor

6,776 posts

181 months

Monday 18th February
quotequote all
4321go said:
mike01606 said:
The cats are actually quite close to the engine. Valve overlap and exhaust tuning cause pressure waves in the exhaust system... particles can 'ride' these waves back into the cylinders.
I wrote above that I’m a one finger typist. You wrote that in the half-hour or so it took me to write and tweak my later reply wink
Thank you both, just the explaination I was after. thumbup

crimbo

1,260 posts

172 months

Tuesday 19th February
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Great vid on insta in there page going round and explaining the engine.

Thom

1,691 posts

191 months

Tuesday 19th February
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Thanks for the informative thread.

Is the block originally using Alusil or Nikasil-plated bores, and what will you be using for the rebuild?

thatdude

2,034 posts

71 months

Monday 4th March
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Any updates for this? I find this kind of content fascinating.

4321go

Original Poster:

480 posts

131 months

Monday 4th March
quotequote all
thatdude said:
Any updates for this? I find this kind of content fascinating.
Fear not; I won’t just randomly abandon the thread! The block and heads are away, being machined. Progress should be relatively swift when they’re back in Ricky’s hands.......

thatdude

2,034 posts

71 months

Tuesday 5th March
quotequote all
4321go said:
Fear not; I won’t just randomly abandon the thread! The block and heads are away, being machined. Progress should be relatively swift when they’re back in Ricky’s hands.......
Great stuff, would love to see some more pictures.

Is there any servicing being done for the transmission?

shalmaneser

3,652 posts

139 months

Tuesday 5th March
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facinating thread; and so good to see a car like this being use properly!

kindai

48 posts

8 months

Tuesday 5th March
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crimbo said:
Great vid on insta in there page going round and explaining the engine.
Got a link?

Thanks!

THE DOBIE

44 posts

148 months

Thursday 7th March
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ricky.rep said:
Morning All,

Thank you to everyone for the kind words, it means a great deal what people think and I work extremely hard to make sure everyone leaves happy.

Also, thank you to the OP for trusting me with his lady and as such the work we are about to undertake.

I won't hijack the thread, and am certainly happy to comment on another thread regarding this topic, but just wanted to clear up some of the decat conversation.

For anyone owning a Pre LP (5.0 engine) Gallardo then there is the risk that the catalysts will start to decay along their joining face with the outer metal pipework. When this happens (especially if on the front face which is especially common on mapped cars) then the engine will draw this material back in on overrun as the induction stroke begins and the exhaust valves have not fully closed. This will then put ceramic material in the bores that gets caught between the piston crown and cylinder walls. Think of it like a grinding paste, over time it destroys the rings, bore coating and eventually the skirt, which removes piston support and causes them to rock and as such the circle self perpecuates.

This is not an issue on the later LP engines which is the same engine as the 5.2 V10 Audi R8, the catalysts are in the headers and I have pushed these headers to 900bhp on our twin turbo conversions with no issues.

For those with the 5.0 pre LP engine then the catalysts are fairly simple to fit, the worst part being the exhaust clamps normally snap and they are quite costly. We use Larini units that have a full decat and a sports cat option for those carbon footprint conscious owners.

If you go full decat and you are running Campi ecu's with the larger oblong throttle bodies, you have a very high chance of no engine warning light coming on once decatted (had a few later ones pick it up but not many). If you have Bosch ecu's with the more conventional looking throttle bodies, you WILL get an engine warning light on and it will need mapping out.

In all honesty, a good map on these once decatted is quite essential. It frees up so much power.

I will keep updating the OP on progress, we are still in a "pricing and planning" stage at the minute.

Any questions please let me know, I would be happy to answer them.

Kindest regards Ricky
REPerformance
Ricky
Im running de cat pipes and a LOC 2 none silenced exhaust pipe work on my Gen 1 you mention a good map is essential after a de-cat do you find the A/F ratio over lean ? do you have you any example power graphs/ A/F ratios for before and after re map.

Durzel

7,655 posts

112 months

Thursday 7th March
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I had 30k less miles on my similarly aged Civic Type-R (not a fussy one smile ) before I sold it. 100k on a Gallardo daily driver - mad props.

And Ricky sounds like one of those sadly rare beasts who you know is passionate about their work and aren't satisfied unless they've done the best they can. Basically a dream company to deal with.

Edited by Durzel on Thursday 7th March 21:09

crimbo

1,260 posts

172 months

Friday 8th March
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kindai said:
Got a link?

Thanks!
Sadly the stories dissapear after 24hours but if you follow them there will probably be more

Trev450

5,751 posts

116 months

Friday 8th March
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THE DOBIE said:
Ricky
Im running de cat pipes and a LOC 2 none silenced exhaust pipe work on my Gen 1 you mention a good map is essential after a de-cat do you find the A/F ratio over lean ? do you have you any example power graphs/ A/F ratios for before and after re map.
You would probably be better off contacting Ricky directly as he doesn't come on here often. ricky@reperformance.co.uk

ricky.rep

4 posts

21 months

Wednesday 27th March
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Hello All,

Sorry the lack of input, I have been in Australia looking after a client.

Attached is a picture showing what I found inside the downpipes of a 2008 Gallardo with low mileage that is in for decat and a remap.

Scary stuff.



In regards to 4321GO, the exhaust manifold nuts were great fun!

They are copper K nuts that leave a large portion of the stud expose, which of course corrodes.

Then, as the nuts are only copper, as soon as they bind on the corrosion they round off quicker than Theresa May vote backfiring!

But anyway, we got those off. The only other major issue was both oil pipes were seized solid so one had to be cut and the other split when we put some force on it with a spanner. Expected as they both run along the underside of the car and are exposed.

At the minute the internals are on order, the block and heads are with my machinist and I am left with the job of cleaning everything until it all arrives.

I have taken provision measurements but until the block has been machined I cannot do my final bearing calculations just in case we have to line hone the mains.

I am not on here too often so if anyone needs me please feel free to drop me an email on ricky@reperformance.co.uk

It is only me at REP so I will always get back to you as quick as possible.

Kindest regards Ricky

4321go

Original Poster:

480 posts

131 months

Wednesday 27th March
quotequote all
It just so happens that I chose this afternoon to pop round to Ricky’s for the first time in about a month. I knew that he had nothing new to show me yet; I just fancied a cuppa and a natter.

As regards my car, Ricky assures me that the specialist parts are in hand. The CP Carrillo pistons are not a stock item, they’re made to order and are almost ready for shipment from the States. Same goes for the valve train. And the block and heads are still away with the machinist. So no photo updates today.

But as regards the photo above.....

It’s not my car, but another 5.0 litre Gallardo that Ricky is de-catting. What you are looking at is the flange at the end of the fight-hand exhaust header. The right hand cat attaches to this and the plates of the catalyst sit about 3 inches away from this flange. Inside the hole you can see a bundle of tubes. Actually, you’re looking at about two and a half of the five individual headers that sit within the two halves of the pressed-steel manifold (ie, each of those inner pipes is connected to an individual cylinder’s exhaust port). The white “crumbs” sitting in one of those pipes is debris from the disintegrating cat! Ricky tells me that this is a low mileage car!!

He posted that post whilst I was driving over. I arrived just as he was removing the second cat, so I was able to witness the same debris sitting within the other manifold.

If you have a 5.0 litre Gallardo, thing seriously about de-catting...........

thatdude

2,034 posts

71 months

Thursday 28th March
quotequote all
ricky.rep said:
Hello All,

Sorry the lack of input, I have been in Australia looking after a client.

Attached is a picture showing what I found inside the downpipes of a 2008 Gallardo with low mileage that is in for decat and a remap.

Scary stuff.



In regards to 4321GO, the exhaust manifold nuts were great fun!

They are copper K nuts that leave a large portion of the stud expose, which of course corrodes.

Then, as the nuts are only copper, as soon as they bind on the corrosion they round off quicker than Theresa May vote backfiring!

But anyway, we got those off. The only other major issue was both oil pipes were seized solid so one had to be cut and the other split when we put some force on it with a spanner. Expected as they both run along the underside of the car and are exposed.

At the minute the internals are on order, the block and heads are with my machinist and I am left with the job of cleaning everything until it all arrives.

I have taken provision measurements but until the block has been machined I cannot do my final bearing calculations just in case we have to line hone the mains.

I am not on here too often so if anyone needs me please feel free to drop me an email on ricky@reperformance.co.uk

It is only me at REP so I will always get back to you as quick as possible.

Kindest regards Ricky
Expensive vehicles or cheap vehicles, exhaust headers are a pain to get off. My old suzuki SV650 motorcycle needed new exhaust gaskets, and my friend ended up grinding the nuts down and then peening them off, leaving the stud pretty intact and very much usable. Took a few hours, mind!

With regards to corrosion and fighting it off, a common practice among some motorcyclists (those ones who ride everywhere all year) is to coat things in a product called ACF50. It does very well at keeping corrosion at bay, might be something worth looking into for items that are exposed and prone to corrosion and potential failure (or just making potential future jobs like this difficult!)

4321go

Original Poster:

480 posts

131 months

Thursday 28th March
quotequote all
I use ACF50 myself to protect the otherwise weather-protectionless chassis of my Lotus Eleven replica (ok, a tarted-up Westfield Eleven!). The only thing that stands between the steel frame and suspension parts and rampant corrosion is paint. And the aluminium panelling is completely exposed. So after a thorough chassis wash, I give everything a light rub-over with the oily, pink fluid. The good thing is that it isn’t sticky and doesn’t attract a build-up of gritty gunk. The bad thing is that it’s a very penetrative lubricant, so you have to be careful not to get too much into the wrong place. Nicely lubricated rivet joints are not an engineering ideal!

Sadly, it wouldn’t have any effect on the exhaust manifold nuts, inaccessible with the engine in situ, after 100,000 miles. I expect that Ricky will reassemble with a smear of Copperslip and the hope that it won’t be him disassembling them in the distant future.......





Edited by 4321go on Friday 29th March 16:58

thatdude

2,034 posts

71 months

Friday 29th March
quotequote all
That is a lovely car 4321go, do you use it often (and what else have you got that's interesting?)

I think with exhaust studs, the best preventative action is to clean them after every drive! I glanced at the ones on my current motorcycle (yamaha FZ1) and they look minging. Hopefully that wont have to come off (but if it does...might as well put on Akrapovic titanium headers / downpipes!). Another issue is that with the heat cycles the metal gets hard spots and such. I dont know if copper slip does anyhting to help but it certainly cant harm (and hopefully you wont have to do all this again...)

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