Omega High Compression Pistons

[courtenaynova]

As the title says...

I want to know what the difference is between NORMAL pistons and the Omega High Compression pistons. Are they worth investing in if the power gains are good???

Please dicide for me...those who have them....cuz I dont wanna keep ripping my engine apart changing pistons to see the differences.

Most greatful chapps...you really must come up to Birmingham for a cup of tea....It is really nice to get out of London Charles...Your butler seems charming, and I must say that your new sheep skin rug is just smashing!

[mikeoxford]

i think there a total waste of money rob you mooooooooooooooose :lol:

[mikeoxford]

but then again you know i aint got a clue regarding it cos we all ready chatted about it

[mikeoxford]

just thought id make you think ooohhh wow weeeeee 4 replies :lol: :lol: :lol: :lol:

couldnt resist me old mucka :P

[Nova Modder]

hmm...
wont the high pressure just give you knocking issues??

and OI i go into b'ham daily... my college is there.. bleh :roll:

[Tazzy]

what college do you go to nova modder?

and Mike, lol, ive now figured how you come to have uch a lrge post count, you must forget to put something in a post so you make another post to say what you originally forgot? surely? :lol:

[Nova Modder]

mathew boulton

right in the city center, its right near digbeth coch station

[Aragorn]

to fit omega pistons u will prolly need a rebore as the pistons are prolly bigger

the rebore in itself will raise compression since your squeezing more air into the same sized area (head volume)if u wanna increase the compression further then u can adjust the dish on the pistons or skim the head

[mikeoxford]

what college do you go to nova modder?

and Mike, lol, ive now figured how you come to have uch a lrge post count, you must forget to put something in a post so you make another post to say what you originally forgot? surely? :lol:

lol sometyhing like that

nah

hands up i post some crap

no more than micky etc :lol:

at least three quaters of my posts are good!!!!

[Ste_Nova]

try half

[mikeoxford]

try half

:o

im telling my mommy

[CP]

Omega pistons are typically used in:

1. High compression N/A engines
2. Forced induction ( turbos etc) engines.

The reason being that the physical forces in these engines are so severe plus very much hotter that normal pistons cant take the pace. These engines are also prone to detonation which is a piston killer

Omega pistons are forged which is the manufacturing process which has the most to do with making them tougher.

Only really necessary in turbo lumps and very highly tuned N/A engines.

[courtenaynova]

I know about forging....as I have worked in the F1 dept at Cosworth Racing...and C.A.R.T

So C.P...All I am going to do is run some beefy cams, worked head, L&B bottom end.

Would you reccomend Omega Pistons or keep my standard ones????

Cheers Matey


Rob.

[big_steve_x]

hmmm, i've been looking at this too, i'm going to go down the stupidly tuned 20xe route, anyway, i'm after power at high revs, as the car won't be for daily use. i spoke to qed, and they do some nice race cams etc, anyway, they said you need deep pocketed pistons, in other words expensive things (which they also sell) anyway, i've heard things like this can cause detonation, so, how can this be prevented in such a high compression ratio engine?? are they any fuel additives or anything like that? does it mean the sngine needs re-building more than normal or anything like that?? give us all the pro's and con's if you can mate.

thanks!

[Ben (lurk75)]

Not worth the ?475 unless your spending nigh on 2k on the rest of the engine.

[mikeoxford]

keep the standard ones rob, money is best spent elsewhere

[_Ben_]

I'll have a set of 87mm *slightly* used Omega pistons for sale shortly. Will obviously need a full set of rings though... pending further inspection (endoscope didn't reveal any nasties on the surface).

Not sure if its been mentioned but these pistons have really deep valve pockets which means you can run quite tight valve timing/. I doubt you'll get much benefit from just changing pistons.

RE: detonation issues, I'm pretty sure that running the correct map would be a good start. Shouldn't get any detting issues with an off the shelf set up like QED supply. High revving engines will always mean more frequent rebuilds. I wouldn't say its as bad as you would think tho, you're not looking at replacing everything every 20k. Assuming you dont do 20k miles at 8k rpm!! You wont be able to do that anyhow as the world would run out of petrol.

[nova---chris]

Im glad someone pointed out that the pistons have a deeper valve pocket.
Also alot more wearing than a standard piston in a modified engine.

With certain cams and kits you have to have these deeper pocketed pistons.

i run accralite pistons in my own engine. these are virtually the same as omega. My car now runs with a 11.8.1 according to the catalogue. but possibly a little more means the heads been skimmed ect.
detonation galore then i take it? wooooo

:twisted:

[big_steve_x]

what damage does detonation do to ya engine?? i've been lookin at the QED420 or QED450 kit, its about ?2500 so i don't wanna buy somethin that will blow me engine up, lol.

[CP]

Detonation is an explosive force that "erodes" the valves and pistons primarily.
The more high powered you have your engine and the greater compression pressures you apply the worse the effects. The worst case scenario would be something like a high horsepower dragster running NOS and not getting enough or any fuel in with it. In this case the engine can melt in a few seconds as tho you had fired a large oxy acetylene burner at the pistons and burnt a hole in them.

Its a major hurdle to getting high horsepower reliably out of engines

[Stuart]

i shall acquire some photos of the pistons that died in an engine i built and then other students mapped (with detonation).

mmm missing bits from piston crowns, yummy