Head Gasket vs Head change

Post by **craptiger** » Fri Oct 01, 2004 2:26 pm

I need to change the head gasket on my 1300 marina engine (don't know what year I'm afraid) and was wondering if now might be a good time to look at replacing the head? I've heard the one in the metro has bigger exhaust valves and so would give better performance?

Is it worth looking into changing the head? Will the extra work be worth it in terms of performance gain? Or should I just change the gasket and leave well alone?

I'd be very interested in anyones thoughts on this. I have a very limited budget and ideally someone will come up with a way I can get a massive performance boost for very little money (in my dreams - ha ha!)

Thanks.

B

Post by **Kevin** » Fri Oct 01, 2004 2:45 pm

A different head on its own may not give that much of an improvement as it will need a carb needle change and poss manifold to get a significant gain, however if you dont have an unleaded head a metro or mini head would be the cheapest way to go unleaded.

Is it worth looking into changing the head? Will the extra work be worth it in terms of performance gain? Or should I just change the gasket and leave well alone?

What extra work if you are having to change the head gasket anyway.
The only extra bits might be for the heater valve and bypass hose if you get a much later head as the holes are blanked off.

Post by **craptiger** » Mon Oct 04, 2004 9:49 pm

so will any head pretty much fit on then? (within sensible reason of course!) Are there any age-ranges for metro heads that anyone can give me off the top of their heads? It's a marina engine 1300 but I don't know any more than that I'm afraid. I'm worried that I might buy a head and it not fit.
As for manifolds etc. I already have a heated inlet manifold and metro carb with appropriate needle so shouldn't need to change too much there.

Post by **Peetee** » Mon Oct 04, 2004 10:37 pm

Some 1300 heads have two additional holes for cylinder head studs. While not impossible to fit, it would be almost certain that you would have to remove the engine and strip down the block to fit the additional studs required. Best avoided then! I have this awful suspicion that all the larger valve heads have these additional studs. The difficulty is that both the cyclinder heads had the same 12G940 casting number.

Visually it's quite easy to see the bigger valve head as each pair of inlet and exhaust ports almost touch. While you are looking, check this area thouroughly as it is here, in the narrow bridge between ports, that hairline cracks can develop.

Post by **bigginger** » Tue Oct 12, 2004 11:12 am

Further to this, I've got a Maestro head that I'd like to fit to a marina 1275, but it has a blanked off hole where the heater valve/tap fits. Is drilling the hole out diy-able using a pillar drill, or do I have to pay someone to do it for me? Any advice on carb-needles etc would also be much appreciated! BTW, I've had a quick scan of the articles on the site, but couldn't find any on head swapping. Is there anyone out there who could compose one to live here permanently for the benefit of ignoramuses like me? Compatability, machining (that valve, whether the block needs to be pocketed for bigger valves atc etc would be invaluable! I'm sure the info's out there somewhere, but it would be nice if it was collated (by someone who actually knows what they're talking about, or I'd do it myself)
and put here. Just a thought...

Post by **Cam** » Tue Oct 12, 2004 11:30 am

bigginger wrote: Is drilling the hole out diy-able using a pillar drill, or do I have to pay someone to do it for me? Any advice on carb-needles etc would also be much appreciated!

Yes, it's DIY-able. I had the same problem when I fitted my modified Metro head onto an Ital block.

What state of tune is your engine?? also what carb/filter/exhaust system are you using. If you can give us as much info as you can about the engine then we can advise (roughly) on which needle to use. Of course a rolling road session will set things up properly.

If your engine is pretty standard with a Maestro head and 'normal' Maestro/Marina/Ital inlet/exhaust manifolds and exhaust system and you are using a HIF44 carb with a paper filter in the plastic housing then a BCZ needle should suit.

Post by **bigginger** » Tue Oct 12, 2004 12:06 pm

Cheers - the motor's not in any state of tune at the mo.I took it out to re-build ( 1st pic below) 'cos it was belching fumes and a) my environmental sensibilities kicked in, b) I reckoned it was enough to fail it an MOT and c) I'm probably going to put it in the othe P/up when it's done, along with a Ford type 9 and the 'scort axle (pic 2 below) possibly built to same sort of spec as yours, cam <gazes with hero worship in his eyes> All a bit of a pipe dream - I've never re-built an engine B4 and want to while I can, but all my time's taken up at the mo with welding in new tie plates and inner wings + fitting 1098 into the black skip to get through MOT and get my daily driver back!

regards

Post by **Cam** » Tue Oct 12, 2004 2:54 pm

possibly built to same sort of spec as yours, cam <gazes with hero worship in his eyes> All a bit of a pipe dream - I've never re-built an engine B4 and want to while I can

I know you are MORE than capable of doing that because you are a Ginger and are capable of anything!!

Just make sure that everything is clean (REALLY clean), have the right tools, follow the manual and get the best quality parts then there should be no problems.