Hi i am buying a turbo kit soon for my eb, i have bought a ef motor to build as the turbo motor but was just wondering what pistons and so fourth do i need for big figures like 300rwkw?

best off getting a set of atomic rods and pistons for the BA engine.
drop straight in with about 8 to 9 thou deck hieght with a 12cc dish.

will will have to have new pockets cut for the exhaust valve

this would be the better way but the standard rods and acl pistons will be fine for that power

there are other way aswell.

like a set of 6inch long eagle small block chev rods are half the price of a set of H-beam BA rods. with some minor crank pin grinding and a different gudgen pin bush in the rod they will fit. ACL/MAHLE do a forged BA turbo piston.

the thing i have found over the past few month doing some pretty indepth reaserch into these engines is that at this point no one make a forged piston to suit the 5.88inch rod found i the pre AU engine.

the stock rod is hell strong. being a forged steel rod some minor prep work will do wonders as with a good set of bolts.

given time, enough people will be calling the piston companies and one of them will step up and make a forged pitson so suit the 5.88 rod.

at this point though the new typhoon/LPG rod is worth looking at(though i havn't seen one up close yet) as they are stronger then the rod used in the BA/F atmo and turboXR6 engine.


on a side note. it was intersting to find the ACL logo cast into the under side of my STOCK ef 6cyl pistons


My head hurts

Good info man, cheers

now theres something thats had me stumped for a long time, do you know of any alternatives for the 4l rod bolts?? cant get arp cos they are metric, AND, if you have pre ED, maybe EF rods i think it is, then you cant even get genuine replacement bolts... because the bolts were superceded to the ed> bolts, which dont properly fit the ea-eb rods...

the knurling is in a different spot, so the bolts are loose...

the only thing you may be able to do is drill the rods and fit the next closest size ARP bolt.

i have come across a lot of people over the last 18months since i was stuck with that problem when i rebuilt mine, that claim to have arp bolts in there 4l, i have asked for proof, or a part number, and never get it when the double check to find they aint got arp's

in mine i just had to re-use my old ones, like i said, i couldnt even get brand new genuine bolts

i would be delighted to know what people are using???

and for pistons, im aiming for 300-320rwkw with acl race pistons, had to use a decomp plate cos when i built the engine, i didnt factor in it would ever be boosting, and got high comp pistons. rods are std with crack testing, closed and honed and balanced. 8.4:1 comp

remembering, MRD made 460rwkw with race series pistons on std rods, and will soon be pushing them even harder once he gets the driveline/auto back in it

a well proven cheap set of pistons you may want to look into, (450rwkw) is what jmm offers... they sell a custom made, turbo specific piston set for $800 from memory, unsure if forged, think they just hypereutectic like the race series ACL.

for 300rwkw, use std rods, balanced, closed, honed, wouldnt even touch the outer surface ie. polishing, shot peening as i many people will say, peening will do jack unless done properly, and how will you know whats proper and whats not, and how will you prove you gained anything by it, and as for polishing, you can actually remove the hard outer coating of the steel, and end up making it weaker than what you started with. I think ACL make a dished version of the race piston, so get that.

if i build mine again, i will have more power in mind, like 400+rwkw, so i would definately go for a set of ARGO rods and ROSS pistons. a guy on ffau has this combo.... $3400 worth though from memory, but it would be tough. how much you wanna spend???

the sky's the limit

Would using an au bottom end work with the ba forged pistons and rods, then have the valve reliefs cut in the pistons?. I know an au block does not bolt strait into an e series but just thinking it might be an idea.

Would the compression ratio be wrong with the sohc head?.

I had 309rwkw for 50,000km on the standard pistons and rods before i blew a head gasket and changed them.

A few people use the ACL ones although not specifically designed for forced induction applications they quite an improvement over standard and should have no problems with 300rwkw.

HINT: use 3" intercooler piping

for the ARP bolts, you have to get the rod drilled to take the next closest bolt, not realy a big issue as it's quite a common thing to do.
even using a new genuine bolt the rod needs to be resized so the only extra is the machining for the bolts.

pollishing will help. because in the forging proces the rod gets inclusions in the outer of the steel. these inclusion are the weak points in wich cracks will form. polishing removes much of this and reduces the places for crack to form. it been proven many times over to work. as for removing the hard out layer, one the thing done the the forged steel escort 2L rod is to reduce the size of the small end. taking away roughly 4mm from the outer of the small end. leeaving only 3-4mm of metal. they run the preped rods to over 7500rpm and the weak point is still in the beam not the small end. you can also after polishing have any number of treatment to harden the outer even more then it was in the first place.



and $800 for hypereutectic pistons. cheap?? you have to be kiding

what is the normal price for a set of hypereutectic pistons?

well, considering they are custom made for a turbo specific aplication, and the ACL 1's are not, then id say its not a bad deal, whats the acl race worth, around the $500 mark arent they?

and, thankyou for the info re. bolts, thats what i thought may have to be done.

and, as for the extent of prepping for std rods, if you were to go to all that touble on a std set, wouldnt you be better off buying some aftermarket forged h or i beams.... i know i personally, wouldnt even consider wasting my time or money performing that to a std set of rods... either leave em std and use acl's or get forged pistons and decent rods as a pair..

Regarding Rods bolts.

Boost6 who used to frequent this forums and knew quite a bit about these engines told me to keep it a secret but since he dissapeared into thin air over a year ago he wont read this.

Use Mitsubishi 4g63 ARP rod bolts. You need two 6 cylinder set.


Everybody also needs to kiss my a-ss for giving this info.

kiss your a-ss?? that info has been posted before dude, just no-one had ever confirmed they fit.

if you search you will find that, but i dont have spare bits and pieces lying around to try them... anyone else ever tried the 4g63 bolts??

they are only cast pistons with a larger dish. ACL EB replacment pistons have a dish of 14cc.. BA turbo pistons have a dish of 12cc go check up the price

for the price of a set of I-beam rods i'd rather spend the time on stock rods.
if you need more strength then that you need top quality H-beams.
you just need to look at your inteded use and weigh up the cost.
JMM did over 400rwkw on preped EF rods.

Who on here ( other than xr6t guys ) have bent or broken a rod due to high psi and not high rpm?