New or used block for stroker kit construction?

[kokkolanpoika]

Hi folks..

Simple question.. Witch one is best construction for +5300-5500cc stroker kit?
New top hat liner block?
2nd hand cracked block witch has top hat liners in it? Pressure tested and its ok?

I hear that new one is better, but i cant hear good reason why..
I think new top hat block can also be cracked?
Top hat liners mean that you cant ever get water in the cylinder? but what about bottom end? Is there any possibility to get water in the bottom end?
What will make guarantee to seal the bottom end? Some glue?

[katanaman]

I assume your on about a Rover engine?

you wont get a new top hat block, you would have to buy a new block and get the work done which will be an expensive route. There may be some tuning shops that will do this right off but the cost will be the same at the end of the day. For that CC you will have to go top hat anyway as it will be beyond the standard bore so your looking at a second hand block and get liners in it. Bottom isn't a problem as the waterway is well away from there so it should seal without problems. They leak out the top because the waterway is so close.

By the time you get all that lot you could have used a better engine to start with and saved a lot of money, something like an LS engine. Stroker kits that size just doesn't make any sense on a Rover engine given the cost and reliability problems.

[kiwicar]

Mike

[Paul B]

Mike

Unless it is for some class restricted racing, why build a mega buck Rover motor that is running on the ragged edge, when the same, or more, power is avaliable from several other sources for probably less money, and will happily do 100,000 miles without a teardown?

[Wotland]

Hello Timo,

May be an cheap option : look Rene Winters website http://www.roversd1.nl/sd1web/ increase capacity Pt1 section

He has installed or knows someone who has installed an Buick 340 in SD1

With spacer you can always use your siamised plenum system RV8

[kokkolanpoika]

I assume your on about a Rover engine?

you wont get a new top hat block, you would have to buy a new block and get the work done which will be an expensive route. There may be some tuning shops that will do this right off but the cost will be the same at the end of the day. For that CC you will have to go top hat anyway as it will be beyond the standard bore so your looking at a second hand block and get liners in it. Bottom isn't a problem as the waterway is well away from there so it should seal without problems. They leak out the top because the waterway is so close.

By the time you get all that lot you could have used a better engine to start with and saved a lot of money, something like an LS engine. Stroker kits that size just doesn't make any sense on a Rover engine given the cost and reliability problems.

Thanks, yes it is an rover engine, and i stay with rover engine. Because swapping/change bigger like LS1 engine is not possible in Finland.. Thanks for stupid LAW...

I have got 2nd hand 4,6block/engine 1 liner is loose, also i have got top hat liners and block is in the machine shop now. And they fit new liners in it near month?. They do the work inc boring/honing to suit 96mm pistons for 460£ inc vat. (and its not first rover engine what they do..) And liners cost me about 233£ inc vat.. engine about 200£ inc vat + heads....
+ stroker kit £££££????

Good to hear that water "cant" go to the bottom end so easily.. One RPI guy/worker say that new block is mutch better option.. But he dosent say good reasons yet.. He is a sales man..

[katanaman]

One RPI guy/worker say that new block is mutch better option.. But he dosent say good reasons yet.. He is a sales man..

Because they will have new blocks they want to sell you!!

Many many tuners would rather use old seasoned blocks rather than new castings. Whether there is a genuine advantage to this or not I have no idea.

By the way what usually happens with liner problems isn't that the water gets in the bores. The compression gets into the waterway over pressurising the system which then blows the water out the expansion tank or some other weaker joint.

[HairbearTE]

This question pops up from time to time on here. There are many who prefer a good used (seasoned) block for the basis of a performance build and for many engines so would I. In the case of the rover engine however I would have to say If you can afford to use a new block as the base then do so.

[minorv8]

Seasoned blocks have gone through thermal cycles that relieve residual stresses from casting process (there are usually stresses which appear during solidification process). When these stresses are relieved the block may distort slightly and play havoc with tolerances. When a seasoned block is used for hi-po engine, it is machined and blueprinted and the tolerances are spot on.

I don´t know whether this is such an problem for an aluminium block. Getting a new 4,6 litre blocl should guarantee that there are no issues like reputed lean mixture / high load scenario that were said to be the root for liner problems in Range Rovers.

Timo, I would check the block when the shop has removed the old liners to check if there is a crack in the block. E-mail me for more info.

[Paul B]

Seasoned blocks have gone through thermal cycles that relieve residual stresses from casting process (there are usually stresses which appear during solidification process). When these stresses are relieved the block may distort slightly and play havoc with tolerances. When a seasoned block is used for hi-po engine, it is machined and blueprinted and the tolerances are spot on.

This is more prevalent with cast iron than aluminium, as it ages and moves about like wood. When I was a machine shop apprentice we had to make a marking out block, from cast iron, which had to be dead flat. We cast them as one part of the job, roughed them to size on the miller, then left them outside in the rain in a pile for a whole year, all rusty and scabby, before machining them to size.

The longer they are left the better, but obviously we had limited time.