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[Marks DTM Calib]

I trust they took the same amount off each head?

[Tezray]

Supposedly  

Seriously though the guy really knows his stuff and both heads appear to be the same....

[v6man54deg Geffd]

Those dowels in the head should be fitted to the block - they hold the head gasket inplace while you are re-fitting the heads.
In the factory we used to fill the bore size etchings (0 or 1) on the block with Omnifit  before we fitted the gaskets- this is the same stuff used for the front A bearing cam caps - I bought mine from ebay cheap.
The bore size markings were causing coolant leaks in the V - the markings were moved on later engines 2.6 & 3.2.
The same stuff (Omnifit) was also aplied to both sides of the head gaskets with a roller.
thats why the head gasket breaks off and bits stick to the head / block.

This process was only stopped when the metal ply gaskets were introduced.




 

Supposedly  

Seriously though the guy really knows his stuff and both heads appear to be the same....

[Tezray]

Well it looks like my rebuild might be delayed.....So of you may know that i'm a student and i'm studying Motorsport engineering and my course involves a placement year. I've managed to get a placement at a place called Grant Motorsport and speaking to Grant today i got talking about my rebuild......Anyway, basically he's offered to have my cams re-profiled by Piper for £221+VAT (normally £110+VAT per cam), gas flow+port my heads for £200 per head (normally £450 per head) and chip and and set it up on the rollers for £300 (normally £500). He estimates that my engine would then be putting out around 240-250 BHP  

The main thing that puts me off is;

A: The money (I'm a poor student!!)
B: The extent my bottom end would cope with this extra power

He said the cams alone would give me roughly an extra 20BHP, so i'm considering just getting the cams done, rebuilding her and then possibly in the future have her re-mapped. What are peoples opinions on this? Whatever happens, it's going to set my rebuild back by about 2 weeks-1 month  

In my opinion, the cams sound like a very good idea as it will feel a lot more responsive to drive but i don't think it'll upset my bottom end.....It also won't upset my bank balance too much lol

Opinions welcome  

[Martin_1962]

Well it looks like my rebuild might be delayed.....So of you may know that i'm a student and i'm studying Motorsport engineering and my course involves a placement year. I've managed to get a placement at a place called Grant Motorsport and speaking to Grant today i got talking about my rebuild......Anyway, basically he's offered to have my cams re-profiled by Piper for £221+VAT (normally £110+VAT per cam), gas flow+port my heads for £200 per head (normally £450 per head) and chip and and set it up on the rollers for £300 (normally £500). He estimates that my engine would then be putting out around 240-250 BHP  

The main thing that puts me off is;

A: The money (I'm a poor student!!)
B: The extent my bottom end would cope with this extra power

He said the cams alone would give me roughly an extra 20BHP, so i'm considering just getting the cams done, rebuilding her and then possibly in the future have her re-mapped. What are peoples opinions on this? Whatever happens, it's going to set my rebuild back by about 2 weeks-1 month  

In my opinion, the cams sound like a very good idea as it will feel a lot more responsive to drive but i don't think it'll upset my bottom end.....It also won't upset my bank balance too much lol

Opinions welcome  

If it is placement - perhaps they will let youy pay in installments

GO FOR IT!

[Marks DTM Calib]

I would just get the heads done, cams can be swapped out considerably easier then ripping heads off.....

[DmcL]

you did remember to finger some oil on the cams/followers so they turn nice and easy before oil pressure is built up when you crank her (with the plug leads off) for the first time right? suppose its not a necessity tho and you could probably get away without doing it.

[Tezray]

Martin, he said if i want he could just take it straight out of my pay!  

My main concern tbh is that all these mods and the increase in power will really upset the bottom end, especially after 158K, what do you guys think? Because the last thing i'd want to do is spend loads of money increasing the performance, only to kill the engine! lol

For the money's sake and protecting the bottom end, i was actually considering just doing the cams and then maybe further down the line chipping her.....I do see your point on getting the heads done though Mark.

Dmcl, when i rebuild her i'll give the cams, heads and followers generous amounts of oil trust me!  

It would be incredible if i did near 250bhp and fit my xe flywheel, she really would fly then  

[Marks DTM Calib]

The bottom end is pretty strong, even has a girdle for extra support.

[omegaV6CD]

Martin, he said if i want he could just take it straight out of my pay!  

My main concern tbh is that all these mods and the increase in power will really upset the bottom end, especially after 158K, what do you guys think? Because the last thing i'd want to do is spend loads of money increasing the performance, only to kill the engine! lol

For the money's sake and protecting the bottom end, i was actually considering just doing the cams and then maybe further down the line chipping her.....I do see your point on getting the heads done though Mark.

Dmcl, when i rebuild her i'll give the cams, heads and followers generous amounts of oil trust me!  

It would be incredible if i did near 250bhp and fit my xe flywheel, she really would fly then  

Hello mate,
it sounds very good offer and it will indeed be a good upgrade. I agree with your concern about the bottom end taking the power. Basically what i would do is to do a bottom end rebuilt and replace at least big end shells and mains+ thrust bearing. Also check what grade the con rod bolts are and upgrade to 12.9 grade if they are not as standard(anyway you will need new bolts). Or you can go forward with the upgrade and just take it easy and hope for the best anyway 158k is not that much.
At that level of tuning i would replace the exhaust manifolds, you could design your own manifolds using the WAVE code by ricardo, ask in your university if they have it.
 

[Martin_1962]

Some good points, shells and bolts!

[Tezray]

Thanks for all your advice, much appreciated  

I think i've decided though......Just to go for the cams for the time being and get rebuilding her. I know it would be good to get the heads done, but here are my reasons for not;

- £400 for approx. 10BHP
- Can't afford it all!  
- I didn't want to make such a big project out of the omega
- It'd set back my rebuild by at least 2-3 weeks, whereas the cams i can get done now
- I'd be very happy with the cams, my xe flywheel and a possible re-map further down the line (once the engines fully run-in and happy once again)
- The heads, block, basically everything are ready to bolt back on right now and i really want to start the rebuild! lol
- I don't want to start messing with the bottom end.....Far too in-depth, time consuming and money i haven't got.

So there's my reasons! Tbh, with the cams re-profiled, re-mapped (to run with my decat pipes) and my xe flywheel, she isn't going to be slow  

Anyway, back to the rebuild! I cleaned up all the piston crowns and had to get the rust off the drivers bank cylinder walls (thats the side the gasket went on) yesterday. Here's a before and after pic of one of the worst pistons! I actually continued to clean it up more than this and got rid of the carbon in the gaps, but you get the idea;

Dirty Piston



Clean piston  



I also removed the oil cooler and found this  :-/



It looks like rust?? The gasket on the cooler really had seen it's day and i could see where coolant had been escaping, same for the thermostat gasket. Do i just use the grey sealer on the new cooler and thermo?

Also, the cooler i removed had veins in it (like a radiator), but the new one i've got doesn't....It seems more of a 'solid' construction if you know what i mean, is this just an updated and improved cooler?

[Markjay]

I would be very sceptical about modifications' extra power claims in general. What I learnt when I used to play around with such things, is that between the 'xx bhp extra power' from the free-flow exhaust, and the various claims made about camshafts, air filters, polished heads etc, I should have doubled my engines bhp but this was far from it...

More specifically, I have some experience with cams (though not on the V6), and it goes like this:

1. Some cars have very good cams to begin with, so it is difficult to gain any substaintial improvement with 'fast road' aftermarket cams!

2. Cams don't make power out of nothing, there is usually a trade-off between low-end power/torque and high-end power - with a manual car used for racing you want the 'rally/racing' profile cam which goes into 7-8k and gives extra power, you don't care about low-rpm (sub-5k) at all. There is a distinct point with rally/racing cams when the engine 'comes-on' the cam, which can be at around 3.5-4.5k rpm, a bit like the turbo boost on a blown engine...

3. Cams which make a significant high-end gain, will also suffer from very erratic idle. On one rally/racing cam I used, it was impossible to get the engine idling without stalling unless the idle was set to 1,500 rpm. This was an extreme example though, in most cases you would just get very bad idle - feels like not all the cylinders are firing - but the engine will still run.

4. The holly grail of cams is the one that does not affect idling, and improves both torque as well as power through-out the rev-range, and allows the engine to go upward of the 7k before power peaks. However, as said before, you can only achieve this if the original OE design is not particularly briliant. If the engine has good cams to begin with, the only way to get some gain is by trading-off idling and/or low-end power/torque.

Now I don't know specifically that the V6 cams are of poor general design, but as said if they are good then it will be difficult to get an overall improvements.

Also, when using high-lift cams, you should also consider using upgraded heavy-duty lifters and followers - but in the very list renew all hydraulic lifters as a matter of course as the high lift cams are very demanding on the lifters, any 'tired' lifters can cause the valves to 'float' and burn.

And last, my experience was with Kent Cams (though collegues used Piper Cams at the time), and it was 15 years ago....

[Tezray]

Wow, some very indepth and usefull information! And as i have never changed the cam(s) on any of my engines this is all quite new to me!

I just spoke to the guy at piper and he said they'd be re-profiled to have 248 duration on the inlet and exhaust and 9.54mm lift. He also would recommend that if my engine has done over 50K (*cough* 158K *cough*  ) that a new set of lifters and followers should be used, priced at £342 for the set   The power band would be from approx. 1800-6000 rpm

So, now the question is, how the hell would i afford the new lifters and followers?! I'm starting to think about just rebuilding the bugger tbh....

[Marks DTM Calib]

Hence why I said heads.....porting is generaly of more use and can help the economy (reduces pumping losses)

You need the grey sealent on the oil cooler plate (the stuff that comes in a small mastic type tube) and pop some around the stat to block joint to.....