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tips, technology, tools and techniques related to vehicle driveline components

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MGBV8
Carl Floyd
Kingsport, TN
(3471 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: MGBV8
Date: May 26, 2016 10:19PM

Did that apply only to the later Rover V8s, Jim, or maybe the 3.9L & up when it was bored to 3.7"?

[Quote]Rover, seeing the motor as its salvation for an aging product line, found that sand casting the block and installing press-in sleeves, (rather than cast in place), at a later point precluded any production problems or costs, but the beginning of longevity issues. This is where the liner issues began. In the Rover mass production techniques, the outer wall of the liner design was changed from a very coarse finish to a fine polished finish, for an easy mass production press fit. The thermal bonding in the cylinder cast in place assembly process, was eliminated completely. This allowed the smooth external walls of the new liners to provide easy installation but allowed the smooth walls to thermally expand at different ratios under the laws of dissimilar materials.[/quote]

[landroverforums.com]


MGBV8
Carl Floyd
Kingsport, TN
(3471 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: MGBV8
Date: May 26, 2016 10:29PM

Back to Dave (RDMG)

Land Rover has been accused of knowing about it & lying to cover it up.

This has been an issue for quite some time. That is why "Top Hat" liner have been discussed & used in England for long time, now. The hotrodders figured out how to fix it as the Rover V8 is the SBC of the UK.

[www.v8forum.co.uk]


mgb260
Jim Nichols
Sequim,WA
(1914 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: Rover 4.6 V8 Triage
Posted by: mgb260
Date: May 26, 2016 10:41PM

My Guess when they went to the newer style cross bolt block. The sleeves I've seen do look pretty smooth. This would be an interesting experiment. Pressure test a block first. Heat block and remove liners. Hone aluminum cylinders for .003 fit. Wire brush sleeves to roughen up. Use Loctite on cylinders. Cool sleeves. Turn over sleeves. Press in. Torque head down with used gasket to set sleeve. Basically install as a repair sleeve as you would in a iron block. Still not a good idea to overheat any aluminum block with iron sleeves.



Edited 1 time(s). Last edit at 05/26/2016 11:16PM by mgb260.


Moderator
Curtis Jacobson
Portland Oregon
(4372 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: Moderator
Date: May 26, 2016 11:37PM

BOPR V8s have their share of problems, but IMHO Des Hammill has done our community a disservice by exaggerating them.

Caution! Alarmist warnings cause anxiety and despair.


RDMG
Dave R
Northern Virginia
(103 posts)

Registered:
04/07/2016 08:29PM

Main British Car:
1979 MGB 4.6L Rover V8

Re: Rover 4.6 V8 Triage
Posted by: RDMG
Date: May 27, 2016 06:53AM

Jim B,

Your recommendations and experiences with the 215 then the 300 are very informative. I think I'm on the same path, except the pick-a-part closest to me doesn't have any trees or brush surrounding the land rovers! Same hills though.

I'm now at a point where I need to weigh the cost-benefits of liners in a rover block vs rebuilding a 300. At the end of the day, once all the "might as wells" of putting in 96mm liners, new pistons and rods, a 300 crank, and 300 heads into a Rover block has been done, I'll basically have a slightly lighter, much more expensive, Buick 300 with a Rover EFI and bellhousing bolted to it. Since acquiring a complete Buick 300 is the cheapest way to get the heads, crank, and front cover for that expensive Rover engine, I'll also have a spare Buick 300 block in the corner of my garage.

Carl and Jim N,

Interesting articles, and I didn't catch the significance of the tapered ends of the liners in the rover blocks. Grasping that issue now, it really doesn't seem wise to invest much time in fiddling with gaskets on a block with my somewhat troubled history, unless I commit up from to re-linering the block. I expect it's very likely the last round of head bolt tightening cracked the block, or that the next round will. I can't understand why Rover engineers would sign off on the idea of tapering the liner ends. It appears that may have been done to only the final years of production? The TTY bolts seem to be a mistake too.

Jim B,

Elsewhere on this site, you've mentioned "wet sleeves," as a risk that people with Rover over-bores have to accept. What are the issues there? An overbore increases the odds of cracks behind the liner, but as long as the coolant goes no further, all is well, I think? I've seen a Turner Engineering flanged liner for sale with silicone o rings at the bottom. Hopefully that would be the ideal solution? I priced the sleeves and the install costs at about $2500 for a bare block. About $200 more for oversize liners (same bore, thinner sleeve, no o rings).

Dave


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5627 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: BlownMGB-V8
Date: May 27, 2016 10:05AM

Dave, any year 300 gives you everything except the heads and 4bbl intake. The '64 4bbl with the aluminum parts is getting hard to find but the later iron engine is still fairly common. TA heads are expensive at about $2500 complete, half that bare but the best heads you'll find, look at Dan's flow testing results. That's where I'd spend my money. (But obviously I didn't since I mounted a blower... but the heads weren't available then.) Smaller chambers than 300, might be good with low compression pistons though. Worth looking at if you plan to use cast pistons. Iron heads will also work quite well and you can upgrade when you are able. You'll pick up another 50 lbs but it won't matter. The iron heads have very good ports compared to any stock aluminum heads. They are huge by comparison, possibly flowing nearly as much as the ported TA heads.

On the intake you have a number of options. You can use a BOPR intake if you fit a lifter valley pan and use spacer plates at the ports. I think TRS sells those parts but they aren't hard to fabricate. Stock 4bbl intakes show up every now and then, as do stock aluminum 300 heads. According to Mikey, the stock aluminum 4bbl intake puts the carb at the same height as the BOPR if I understood him correctly. Using the Rover EFI with spacer plates may result in hood clearance issues, so a scoop or bulge may be an issue you'll need to deal with. Thankfully a quality glass hood is available to solve that problem.

The bell and flywheel are cheap and available. Use BOPR headers and engine mounts, 300 water pump. The guys that have them really like these engines.

That Rover crack, in the photos I've seen it runs horizontally and it's obvious from looking at where it is that deformation of the deck and stud boss is the reason for it. Proper design would have the stud boss tapering down past the end of the hole to blend with the cylinder wall. Seems pretty obvious they didn't do that, but just truncated it below the hole. All metals deform when stressed and that is a high stress location. Cast does not take deformation well and is prone to cracking. So it doesn't take a lot to see what is happening there.

The chamfer on the liners was in the category of "Very Bad Ideas". I would agree that the chamfer probably was intended to go down, not up. Somewhere there was a mix-up.

The wet liner comment had to do with very large bore Rover engines, which begin to approach Dixie-Cup status. An engine designed for wet liners tends to be heavy. Either the deck is reinforced, the studs go all the way to the bottom of the water jacket, or both. The liner cylinder does nothing to add rigidity or stability to the engine block, unlike a dry liner engine. So when you remove most of the liner enclosing bore material you substantially weaken the block and deck, without any very practical means of getting that strength back. Everything then flexes more, and the big bore engine has a short lifespan. We had one guy on here build one of those and apparently it didn't make it past the dyno testing stage because we haven't heard any more about it. I hope I'm wrong about that but I have my doubts.

Any kind of flex is a bad thing in an engine block. For aluminum to resist flexing forces the remedy is to use more material. This makes the block heavier, and this is the reason the Chevy LS block is as heavy as the iron 300 block. So for a given strength, often the weight advantage of aluminum is much less than you'd think. The iron Buick block has been proven up into the 700 hp range, well above what the BOPR is capable of. This means it is more rigid, more stable, and more reliable at any power level. The deck height increases by 9/16".

Jim


Dan Jones
Dan Jones
St. Louis, Missouri
(259 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: Rover 4.6 V8 Triage
Posted by: Dan Jones
Date: May 27, 2016 04:42PM

Not sure where you are located (I'm near St. Louis, MO) but, if you decide you want to go down the Buick 300 path, I have a disassembled 1964 Buick 300 that I'd sell. I also have bare and rebuilt 1964 aluminum 300 heads and matching 2 and 4 barrel intake manifolds. I might even be persuaded to sell the ported Buick 300 heads (1.775" intake and 1.5" exhaust Stage 1 Buick V6 valves, roller rockers with shaft end stands) and matching Huffaker single plane intake.

Dan Jones



RDMG
Dave R
Northern Virginia
(103 posts)

Registered:
04/07/2016 08:29PM

Main British Car:
1979 MGB 4.6L Rover V8

Re: Rover 4.6 V8 Triage
Posted by: RDMG
Date: June 01, 2016 08:26AM

Dan,

I'm not on the market for a 300 yet, but will reach out if I get there!

Jim B,

Regarding the de-stroked 300, would using the small-chambered TA Performance heads solve the piston/rod problem? They would reduce combustion chamber volume quite a bit, perhaps permitting more piston/rod combos?


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5627 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: BlownMGB-V8
Date: June 01, 2016 10:09AM

ON one hand it helps, on the other it hurts. The lower volume, as you say, gives options. But, it also means you have to either move the piston down in the bore which means no squish area, or you have to use a piston with a large dish. Common dish is around 13cc, you'd be looking at something around 35cc I think.

Jim


MGBV8
Carl Floyd
Kingsport, TN
(3471 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: MGBV8
Date: June 06, 2016 05:26PM

Just another observation on the Rover liner issue.

Over the years, I have not heard any issues with the Rover 3.5L engine. I think this whole mess started when they took out more aluminum to insert a larger diameter liner for the 94mm/3.7" bore engines (everything but the 3.5L). I guess there was enough meat in the block for the 3.5, but not really enough for a bigger bore.

Sure is nice to have a Buick/Olds 215 with a cast-in cylinder. :)


pcmenten
Paul Menten

(242 posts)

Registered:
10/08/2009 10:40AM

Main British Car:


Re: Rover 4.6 V8 Triage
Posted by: pcmenten
Date: June 06, 2016 06:04PM

Hi Carl.

I was recently thinking along the same lines - my Olds block has cast-in liners, so, in spite of its smaller bore, feels like a safer bet than the 4.0 I have sitting in the corner of the shop. I'm thinking a 260 stroker Olds is the way to go for now.

Someone mentioned vibration caused by low rod/stroke ratios. I'm wondering if that vibration can be balanced. I realize that the vibration is proportional to the engine speed, and that it occurs somewhere around 45 degrees ATDC. I suppose balancing it means calculating the moment of the force at some average RPM, such as 2200, and using that in the calculation of the counter-balance forces. A good excuse to brush up on calculus and physics.

Paul


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5627 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: BlownMGB-V8
Date: June 07, 2016 01:05AM

The cast in liners are a very good thing, however that really doesn't make the BOP engines any more reliable IMO. From what I have gathered the Rover castings *may* be denser and therefore have more strength in areas like threads where the Olds and Buick blocks really do fall short. I have yet to see an Olds or Buick block that would comfortably take full torque on either the head or main bolts without at least a feeling that the threads were pulling or stretching, and that's not a feeling you want to ever get when putting an engine together. Every time I built one of those engines I had to stick to the low end of the torque specs.

So while I agree with Carl's assessment of Rover engines and their troubles, I do not feel the US versions have any real advantage. In fact, the 3.5L Rovers could very well be the most reliable of the lot, but if building for power that isn't saying much.

Which again explains why I went to the iron block. First there is the bore size: 3.750" standard and a .050" overbore is generally going to be OK. (sonic check the walls) The threads will not pull out and torque will be firm and positive, a wonderful improvement. Then there is the possibility of stroke increases or decreases. For this you pay a weight penalty of 80 lbs. Big deal. You're at the same weight as a 5L SBF swap. Plus maybe some fiddling to get the intake you want. But all BOPR heads fit so that's a big plus.

I'm still convinced there is a rather large cross section of owners who value the corporate stamp of legitimacy, in that MG installed Rover engines so any MGB with a BOPR has a direct connection with implied factory approval. That is right and proper and as it should be. Not to denigrate any other engine conversion, but only the BOPR V8 fits this category. However, the 300 is the same engine. It has an iron block, somewhat taller decks, and a 1 piece intake rather than using a valley pan but is otherwise identical, and most people would not be able to differentiate between the two without a magnet. (Interestingly, the Australian P76 version also had taller decks.)

Jim


MGBV8
Carl Floyd
Kingsport, TN
(3471 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: MGBV8
Date: June 07, 2016 10:48AM

Well, the Rover blocks are reported to be heavier. I have a bare Rover block that I can weigh. Anybody have a bare Buick 215 block to weigh?

I don't buy the denser, stronger Rover casting. i had no problem pulling the threads out of one of my 3.9 Rover blocks when torquing the ARP head studs. They let go right at 50-55 lbs.


roverman
Art Gertz
Winchester, CA.
(2901 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: Rover 4.6 V8 Triage
Posted by: roverman
Date: June 07, 2016 11:16AM

I made a "test coupon", from a 215 block. It tensile tested higher than what aftermarket, T356 blocks were . 215's density is grater than Rovers, because they were semi-permanent mold vs sand cast. roverman.


waterbucket
Philip Waterman
England
(66 posts)

Registered:
07/30/2011 01:08PM

Main British Car:
1978 MGB GT

Re: Rover 4.6 V8 Triage
Posted by: waterbucket
Date: June 07, 2016 03:57PM

The Rover block question is not as simple as it has been made out, there were considerable numbers of block/liner failures in these engines. As I understand it the 3.5 gave no problems at all and the same with the 4.2 but they started with the 4.0 and 4.6 engines. The bigger bore of these engines left very little metal behind the liners, the bores were ultrasonically tested for thickness and were graded accordingly. I think a dab of paint was put on the valley to distinguish the three thicknesses, 4.0 engines received the thinnest and medium and the 4.6 received the thickest and mediums if needed. The idea being that the longer stroke could cause the liner to shift so all thick bore walls went to the 4.6.
That was not the only problem that the Range Rover had, the top coolant hose was prone to airlocking, causing the engine to overheat and this in turn caused the liner problem. Of course the vast majority of owner did not know or understand the overheating problem and the engine then got its bad reputation.
If you read the information to the top Rover V8 engine modifiers they will confirm that their replacement top hat liners will cure the problem of liners, but it should not have existed in the first place. It is typical of the engineers/ management that lasted for the best part of four decades where cars were released for sale before sufficient testing was performed on them. There was virtually no car made by the Leyland group where the motoring press and the public were not critical of the quality. Those of you in the USA were spared the Allegro whose new owners were told not to jack it up or the windscreen could pop out!



MGBV8
Carl Floyd
Kingsport, TN
(3471 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: MGBV8
Date: June 07, 2016 06:09PM

]quote]As I understand it the 3.5 gave no problems at all and the same with the 4.2 but they started with the 4.0 and 4.6 engines[/quote]

The 3.9, 4.2, 4.0, & 4.6 all had the bigger 94mm bore. Glenn Towery had first hand issues with the 4.2 block.


waterbucket
Philip Waterman
England
(66 posts)

Registered:
07/30/2011 01:08PM

Main British Car:
1978 MGB GT

Re: Rover 4.6 V8 Triage
Posted by: waterbucket
Date: June 08, 2016 04:20PM

I have now found the reference from Des Hamill's book "how to power tune rover V8 Engines". He states that in 1993 Land Rover were aware of the problems with the variation in wall thickness in 4.2 engines and later 4.0 and 4.6. The wall thickness of the bores varied between 2.1 and 3.0 mm. After 1997 blocks were given one of three grades blue minimum of 2.2, yellow 2.5mm and red 2.8mm a daub of the appropriate colour was put onto the valley of the block. Until 1997 4.0 engine were made from 2.2mm to 2.5mm blocks and 4.6 engines 2.5mm and above. after 1997 4.6 engines were only made from red blocks ie 2.8mm and above unless there was a shortage of thick walled blocks. Some pre 1994 blocks left the factory with as little as 1.2mm of wall thickness.
He also states that in the P38a Range Rover a combination of top radiator hose failures and a coolant running temperature caused the rise in the number of failures.
I think a conclusion could be drawn that if you have a sound 4.0 or 4.6 and control the water temperature then there should be no failures. I also accept Curtis's remark that Des Hammill exaggerated the problem, but that problem must be real otherwise we would not have so many companies offering different liner solutions in the UK. Obviously with the increasing age of these cars (the youngest is now 14 years old) the majority of them are long since gone to the scrap yard.
Philip


RDMG
Dave R
Northern Virginia
(103 posts)

Registered:
04/07/2016 08:29PM

Main British Car:
1979 MGB 4.6L Rover V8

Re: Rover 4.6 V8 Triage
Posted by: RDMG
Date: July 20, 2018 04:45PM

Reviving an old thread, but I posted some more details on my bargain 4.6 on my build page, and thought you guys might be interested.

Iím still not certain if the block is cracked, but Iím totally certain the engine needs to be completely disassembled and cleaned, with new bearings all around.

Next step is a pressure test, hopefully this weekend.

The head bolt holes are shot, and will need helicoils or time-serts all around, but that might be the *only* defect in the block casting. The new gaskets didnít appear to be leaking, and the liners all seem to be in place. All cylinders still have clear cross-hatching too.

The front cover gasket was prob the factory original, and it was in terrible condition. there were suspicious sludge ďtrailsĒ on the outside of the block near the front cooling passages too.

I may be a hopeless optimist, but itís still technically possible that coolant was entering the crankcase at the front cover, and that the block isnít cracked behind a cylinder, and that the head gasket replacement didnít correct the problem, and that the questionable decision by the mechanic to torque all headbolts again likely ruined his ability to cheaply repair it.

The oil filter pieces are a mystery though, to me anyway.


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5627 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: BlownMGB-V8
Date: July 21, 2018 10:28AM

I think Phillip's comment that by now most of the 'bad' engines have been recycled is valid and even more apt when applied to the 215's which also had porosity issues. You never hear of that these days because those engines are gone. However that doesn't mean one won't occasionally show up.

Carl, please do weight your bare block. I weighed several 215 blocks and they came out to 60 lbs. Precise actual should be within a pound or so of that, with the main caps and bolts. If as you and Art say the metal is not more dense then certainly sand casting would have added more metal. Another oddity is that I have heard of some Rover head bolts being torqued down to as high as 90 ft/lbs. That strikes me as very odd given your and my experience.

I completely understand the desire to build a light engine. However, bear in mind these were never expected to last even 100K miles. At the time of their design expected engine life before unacceptably high oil consumption and other issues was around 50-60K miles. Warranties, when they did begin to appear, were for about half that. Timing chains regularly failed at 30K. Modern engines, designed for 200K+ are engineered for great rigidity in the block and other components. This minimizes distortions and harmonic vibrations that cause wear and other failures, and that's one of the biggest reasons for the increased service life, along with cleaner gas and better oil. Buick addressed this problem by switching back to cast iron and their subsequent engines became renowned for exceptionally long service life despite their remarkably light weight for a skirted block. Rover did not really address the problem, stretched out their production run with band-aids like the cross bolted block, and eventually replaced the engine with something more reliable.

What I find very interesting is that the iron block Buick and the Rover *are the same engine*. The only fundamental difference is the material they are cast from. Anyway, I can say from working with both that Buick's choice was the right one. From an engine builder's perspective the iron block is so far superior to the alloy one that they simply are not even in the same League. Yes, you do take an 80lb hit on the weight. But it is SO worth it.

Jim


Bland
Tim Bland
Oregon
(8 posts)

Registered:
01/22/2017 11:15PM

Main British Car:
1980 Triumph TR8 Rover 3.5

authors avatar
Re: Rover 4.6 V8 Triage
Posted by: Bland
Date: July 23, 2018 01:05PM

I have bare Buick and Rover 215/3.5 blocks that I can weigh tonight.

Tim Bland
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