Buildcraft combustion Engines have only two ways to cool it...
First water... That will be consumed pretty quick and BC Pipes are mostly not able to keep up (thats a reason why people yell we need bigger pipes),
The Second and Painfull way is Liquid ICE. If you got to the point where you got easy access to the materials it is a extremly powerfull coolant. It is a couple 1000 times better then water.
So now here is liquid Coolant. You need Lapis lazuli to create it and it is not that easy to get access to and it takes a little bit of time.
I added it already in my 1.6.4 version and suggest that it is keeping up the half time of liquid ICE (Number of Water = 0,0023. Liquid ICE = 10) I would say 4-5 would be perfect for LiquidCoolant.
And The TE3 Liquid Cryophium or something i would give him the same number as liquid ice because its the same thing just another name...

this is an IC2 thing to fix, there is a coolantRegistry in the BC api, other mods (or something like BC compat) should register the coolants there

There is (was? I haven't tested with recent builds yet, but it was functional in 1.6) also a 3rd way, which is Ice Blocks themselves. Put them in CE's inventory and it'll cool the CE (Combustion Engine) down.

And I wouldn't say BC Pipes are "mostly" not able to keep up. I would say BC Pipes are "slightly" not able to keep up IF you have a dozen of Combustion Engines.
I do not know about you, but its been more than a year since the last Combustion Engine blew up on me, so I would say the pipes have done pretty good job (and this was before the pipe quantity upgrade in BC 6.2). Also, the fluid pipes have received quite a buff in capacity since 6.2 for your information.

@raga combustion engines use min 1mb water every tick.
And my engines do not blow up because i use liquid ice as coolant or biomass engines from foresty.
Note Liquid Ice is needed maybe 1 mb per minute or something. Maybe even more.

And because i am now the coder of IC2 Classic i will make a compatiblity xD.
1.6 for the win!

@raga and ICEBlocks count as water! And to create ICE blocks it takes also a lot of time!
If you do not use IC2 Compressors with snowballs and 20 overclocker upgrades.
Also it reduces the amount of lag because you have to run less machines :)

my Engines do not blow up because I use water.

Moved.