9 replies to this topic

[tomgale]

I'm planning a new engine, changing my 998 to a 1098 and I purchased a +20 A+ block and 1098 pistons. but when I got it it turns out the bearing caps have gone AWOL at some point in its life, I know these are matched to the block, and it isn't much good without them.

 

so my options are (if they're even possible)

 

1- acquire new bearing caps and line bore the block to suit them

    pros- can use block with correct 1098 number, didn't waste money on it, can sell my 998 after

    cons- who would even sell caps separately?, can line boring the block to suit new caps even be done?

 

2- take my current 998 block out, re-bore it to +20 to suit pistons, build engine on that block

     pros-re-boring is probably a more common operation? easier to get done?, can keep car's original engine number (though at the wrong displacement)

     cons- have to have the engine out of the car for much longer, annoying as its my only vehicle.

 

so, what Im asking is, if option 1 is possible, how does it compare cost wise to option 2?

 

thanks! 

[Carlos W]

Line boring is quite expensive I believe.

 

Reboring is likely to be cheaper

[dean]

option 3. find another 1098 engine and rebore it. would be the cheapest way, plus you keep the 998 in your car and your car on the road. 

[ACDodd]

The 998 and 1098 blocks are the same. Simply fit the 1098 crank and pistons into the 998 block. Rebore the 998 to fit the +0.020" pistons.

 

AC

[tomgale]

anyone know roughly the price difference between a rebore and a line bore? if its only 50 quid or so I'll probably go with the line boring, I know the blocks are the same but being without a car for a few weeks would be a huge pain in the arse. as for option 3, my brothers clubman estate's engine is on the desk at the moment, I could borrow his block then give him mine, but his isnt A+ whereas all the transfer and primary gears ill be using are, is this a problem?

[Cooperman]

Rob Walker Engineering of Witney, Oxon., can line-bore main bearing caps.

You could call him for a price.

[dean]

line boring.

 

http://www.robwalker...inereaming.html

 

cylinder boring

 

http://www.robwalker...der_boring.html

[Carlos W]

I'll keep that 1275 block with the caps missing at that price

[The Principal]

If you need new bearing caps you will need to have the thrust faces machined too, last time I had steel caps with line boring and thrust faces machined by Gosnays cost me best part of 500 excluding the steel caps. New caps are available via MED or Swiftune incase your lottery numbers come up.

[tomgale]

yeah, thats... a lot. dont suppose anyone has a +20 998/1098 block lying around? ;)