Looking to see opinions on what the best piston and rod setup would be for a big powered 2.5 build. Hoping for a reliable 600-650hp.

Been recommended Mahle 2618's but how do cosworth, wiseco, rcm pistons compare ?

Had a look but can't find any real world facts and figures

 

I'm led to believe carillo rods are one of the best @ £1k ish a set

 

Would be more worried about the 2.5 piston liners cracking on a 600bhp engine than the rods or pistons. In general anything over 450bhp on a 2.5 even with closed deck inserts is risking cracked liners.

 

 

Omega pistons and Pankl rods , these were in my WRC engine , next best rod is Arrows
Cheers Ian

 

Well my new block is currently at AS Performance getting ductile liners installed as well as cdb insert. Hopefully won't have that issue with them fingers crossed should have put that in my original post sorry

 

Excellent news. Alyn is the nuts.

 

If money is no object then sell your existing block and go an buy the willall racing cnc'd block @ £11k lol Proven to handle over 1200hp

 

Well by the time I'm finished I would probably been just as well 😂.

 

What kind of power was your wrc engine running Ian ? I heard of pankl but never seen much from them

 

Power is low for the spec on a WRC engine as they are restricted , they have a 34mm trumpet fitted into the inlet of the turbo , which reduces airflow at higher revs so you lose boost , Graham Sweet who build most of the WRC engines , recons mine was at around 330-340 hp , but they are built for torque , mine was around 500 lb ft , it was high compression engine , 11-1 comp ratio , with 2 bar of boost , with very little lag , it did have to run on 102 octane race fuel , would pull from 2k revs , but was running out of puff at around 5500-6000 revs , the last of the WRC Impreza's were leaps and bounds better , touching 360 hp and 700 lb ft from 1500 revs ! they literally had a rocket in the up pipe to spin the turbo to produce boost , amazing technology from a WW2 tank lol.

A lot of the bolts on my car were made by Pankl , they are at the top of the pile for rods , and Omega for pistons , RCM sell Omega , I have used them on various engines over the years and never had an issue.
Cheers Ian

 

Jesus that's some power figures! I remember reading the wrc engines being limited to around 350bhp but wasn't certain.

 

get one rated to 1000hp for quite a bit less from the states if your wiling to import and comes with a warranty aswell lol

https://www.iagperformance.com/IAG-S...g-eng-1452.htm

 

I did look at these and as far as I can see they are just standard ej257 blocks with a cdb conversion plate in them. Strong money for that plus some pistons and rods

 

bit more involved than that if you read it and I didn't think it was strong money for a 1000hp short block ,,, mine was similar and its not rated that high ,, even there fully blown billet block is cheaper than a uk big build lol ,, and these engines are making 1000hp all the time over in the state in everyday peoples cars (not big companies trying to promote stuff) ,,, show me one normal person even close to that number with a 2.5 over here lol

iv got a fairly well built 2.5 but its still only rated to around 650 so iv capped it at 530 to be safe and has been fine for the past 4-5 years now ,, other parts inside are rated higher (Carrillo rods 1000hp) but a build is only as good as its weakest part lol ,,, not sure why our engines in the uk can't be built with the same power figures in mind for the same sort of prices

 

are there any links to these 1000hp builds?

 

 

at sensible costs then the Mahle 2618 race piston and Carrillo rods takes a lot of beating............

have plenty of customers at 7-800 with this combo

 

who told you that?? we have been converting engines for years for most of the tuners in the UK / Europe as well as our direct customers and there are plenty of builds at 600 or so on std liners with our insert

 

Is we are just talking about the case half's, all it says in the description is converted to closed deck and honed to 99.75mm I will admit when you watch videos and go on America Subaru forums they are all running crazy power on relatively basic engines compared to how much they are modified and tuned in the uk I don't understand it.

 

For some reason, it seems that americans make the same HP at the wheels, as the UK make at the crank... People should form their own opinions of why this might be

 

 

I stand corrected then!

I'll have to look back where that nugget of info came from, but I'm almost certain it was a builder who said this. From memory I think it was Paul Finch, but I will double check this. Please don't quote me. Lol.

Also, not questioning you or your work at all, I know you've built some amazing 2.5 engines with those closed deck inserts.

Been searching and I can't find the reference to 450bhp limit yet. Will keep looking, it's annoying me now as I've seen it somewhere.

 

I posted a link to one of there builds that is rated to 1000hp and comes with a warranty lol ,,, isn't even there biggest spec build by far
The IAG Stage 4 Tuff Short Block has a power output rating of 1000BHP.

they do another extreme build and then there fully billet block

to be honest i didn't think my turbo from the states would make the power they claimed as we all consider there power figures to be high but in the end it made more than I expected by quite a bit lol so not all there figures are made up lol

 

I won't mention them on here but I know two quite bit well known engine builders that wouldn't rate a 2.5 over 450 for me when I wanted one built so iv heard the same claims,,, so clearly not all builders are able to build these to same a high standard

 

 

 

we wouldn't rate a std block over 450 either but the inserts make a huge difference, we undertake plenty of work for tuners who originally had poor things to say about 2.5's so must be doing something right...........

 

everything iv ever imported has been fine , just need to take customs charges into account with everything

 

i run with both carrillo rods and mahle 2618 pistons