The V8 Owners Forum -

Can I use the later 10 bolt head gaskets on the earlier 14 bolt cylinder heads of my Rover v8, provided I just nip up the omitted outside 4 head bolts?

I use my 14 bolt heads on my 10 bolt block,
So with that logic,I can't see a problem !

stroprock wrote:Can I use the later 10 bolt head gaskets on the earlier 14 bolt cylinder heads of my Rover v8, provided I just nip up the omitted outside 4 head bolts?

If you use 10 bolt gaskets they may well not even have the holes for the outer bolts so you can't even fit them. (Maybe the gasket does not cover the holes?). My 4.6 setup is like this, I'm running a 4.6 block with heavily modified 14 bolt heads. Even on a 3.5 lump I would not fit the outer bolts (well not torque them up), they just put a side load on the heads which causes the head gaskets to blow in the valley area of the engine.

sidecar wrote:Even on a 3.5 lump I would not fit the outer bolts (well not torque them up), they just put a side load on the heads which causes the head gaskets to blow in the valley area of the engine.

This is what I have heard. So it sounds like I can go ahead and buy a set use Elring 10 bolt gaskets. Thanks guys.

Yes you can.

Chris.

You will lose some CR but a 0.5mm skim will sort that out and its a good idea to skim the heads anyway if they have never been skimmed since they left the factory.

The outer row of bolts arent needed.

The Elring gaskets are the larger 94.4mm bore size for the 3.9. Can I use these on a 3.5 with 89.9mm bore?

stroprock wrote:The Elring gaskets are the larger 94.4mm bore size for the 3.9. Can I use these on a 3.5 with 89.9mm bore?

Er, no!

The fire ring on the gasket has to be at the edge of the bore otherwise you will end up pockets of mixture that either never get burn't or they detonate which is no use either.

sidecar wrote:

stroprock wrote:The Elring gaskets are the larger 94.4mm bore size for the 3.9. Can I use these on a 3.5 with 89.9mm bore?

Er, no!

The fire ring on the gasket has to be at the edge of the bore otherwise you will end up pockets of mixture that either never get burn't or they detonate which is no use either.

Ideally yes...but really not that critical.

Even on the smaller 4.8 and 5.3 LS engines, people still use the much larger bore LS9 gasket with no ill effects.
Likewise some of the EJ22 based Subaru builds. Few make gaskets for these, so they use the much larger bore 2.5 gaskets, again with no problems.

stevieturbo wrote:

sidecar wrote:

stroprock wrote:The Elring gaskets are the larger 94.4mm bore size for the 3.9. Can I use these on a 3.5 with 89.9mm bore?

Er, no!

The fire ring on the gasket has to be at the edge of the bore otherwise you will end up pockets of mixture that either never get burn't or they detonate which is no use either.

Ideally yes...but really not that critical.

Even on the smaller 4.8 and 5.3 LS engines, people still use the much larger bore LS9 gasket with no ill effects.
Likewise some of the EJ22 based Subaru builds. Few make gaskets for these, so they use the much larger bore 2.5 gaskets, again with no problems.

Why do what can only be described as a bodge when you can get good composite gaskets with the right bore size.

sidecar wrote:

stevieturbo wrote:

sidecar wrote: Er, no!

The fire ring on the gasket has to be at the edge of the bore otherwise you will end up pockets of mixture that either never get burn't or they detonate which is no use either.

Ideally yes...but really not that critical.

Even on the smaller 4.8 and 5.3 LS engines, people still use the much larger bore LS9 gasket with no ill effects.
Likewise some of the EJ22 based Subaru builds. Few make gaskets for these, so they use the much larger bore 2.5 gaskets, again with no problems.

Why do what can only be described as a bodge when you can get good composite gaskets with the right bore size.

Because on powerful applications, composite gaskets are crap. MLS on the other hand hold lots of power.

The GM LS9 is a very very good gasket, and being GM, it's cheap. It's better than the other MLS gaskets intended for the correct bore size, likewise the Subaru applications.

I agree that yes ideally you would use the correct size gasket for the head/bore in use if they are available

But when you dont....it really doesnt seem to make any odds even on engines pushing 300hp+ per litre.

Obviously gaskets should be available for the RV8 in the correct sizes and most will not be very high powered builds to need anything special either

stevieturbo wrote:

sidecar wrote:

stevieturbo wrote: Ideally yes...but really not that critical.

Even on the smaller 4.8 and 5.3 LS engines, people still use the much larger bore LS9 gasket with no ill effects.
Likewise some of the EJ22 based Subaru builds. Few make gaskets for these, so they use the much larger bore 2.5 gaskets, again with no problems.

Why do what can only be described as a bodge when you can get good composite gaskets with the right bore size.

Because on powerful applications, composite gaskets are crap. MLS on the other hand hold lots of power.

The GM LS9 is a very very good gasket, and being GM, it's cheap. It's better than the other MLS gaskets intended for the correct bore size, likewise the Subaru applications.

I agree that yes ideally you would use the correct size gasket for the head/bore in use if they are available

But when you dont....it really doesnt seem to make any odds even on engines pushing 300hp+ per litre.

Obviously gaskets should be available for the RV8 in the correct sizes and most will not be very high powered builds to need anything special either

I know that MLS gaskets are good but the OP is talking about using 3.9 COMPOSITE gaskets on a 3.5 engine not an LS engine and that is what I'm refering to. You can good comps that are made for the 3.5 so why stick 3.9 gaskets on it?

You can get MLS gaskets for the 3.5 lump but unless the OP is going to supercharge/turbo charge or use alot of NOS then they are OTT...
http://www.burtonpower.com/parts-by-bra ... 6-040.html