hey guys.
I am about to start a full rebuild for my EDxr6 to handle a supercharger. I want to know which is the best engine to get to rebuild- EB,ED,EF,EL,AU,Tickford??? etc.

I have been told that AU engine would be the best but why? also been told that tickford blocks are made of slightly better material?? Any input would be great guys. The aims of the engine are to be very strong and I will be doing alot of head work for flow. I am wanting to keep my inlet manifold as it is on gas research.

Thanks a bunch

tickford blocks are the same

Au engine has a few nice features - slightly longer rods and more crank support. Apparently the rods are not as strong as e-series though.

If your going all out with some low comp pistons its not really going to matter what block you start with. Id just look for anything with good bores so you wont have to take much out when you rebuilt.

AU engines are much stronger in comparison with the E-series engines....and the AU engines don't seem to blow a head gasket easily such as the ES engines....

thats moreso to do with the fact the AU ran the steel shim head gasket. a Eseries donk with the AU gasket (assuming the block and head are nice and flat) wont eat headgaskets either. If your going nutso, any engine will do.

Why? What do you base that on? I'm not saying your wrong, just interested to know why...
Blowing of the headgasket is to do with the different type used between the two, not because of the block.

As for which head to use matey, I've been told the 94DT Tickford head found of EF's and that is the way to go, but if your having work done to it then I guess it won't matter. Prolly just stay away from hybrid head as lack of cam choice.

Yep thats right - the e-series head gasket problem had everything to do with the type of head gasket used. Put an E-series head gasket on an AU and youll have the same problems, put an AU head gasket on an E-series and problem solved.

As for the AU's being much stronger - They do support the cranks better but how many SOHC's have failed because of lack of crank support. With 7 main bearings the crank has always been well supported. Pistons are not really an issue because if you are seriously rebuilding it you will be going aftermarket anyway. That leaves the rods, and as I said above even though the AU's are longer (marginally better geometry) they are apparently weaker in turbo applications.

If I was rebuilding an engine for a forced induction I would get any SOHC, rebuild with EA ACl race series pistons (11cc dish) and get the bottom end balanced - thats it. This will be not only bloody strong but also cheap. To take the next step your looking at forged pistons which will cost more that a rebuild with EA ACL's on there own. Then you need a 6" rod so your looking at xr6t or better. The cost will quickly blow out.

It all depends on how much power your chasing.

au head gaskets were improved. try using the graphite ones i have found them to work well. i was told that the EL series one heads were the best of the lot but the blocks are much the same

in a different topic, arm79 said that the EL Hybrid blocks were the best, prolly easier than fitting an AU one in as you won't have to grind the K-frame or anything.

Fitting the charger up should be your first step. I'd really like to see this. I have toyed with the idea of an EATON M90, mounted in place of the air con compressor. A little concerned about the clearance around the engine mount and air inlet at the back of the charger but i *think* it would fit.

All these mods will revolve around the charger being a viable fitment option. This will involve quite a bit of fabrication, some of it straight forward, some of it a right pain. And yes you will have to spend alot of money up front on the charger even if it doesn't work out. Better to find out after $1k of spending than after $6k of spending though. This is not necessarily cheaper than a turbo fitment....

HEADS: In a boosted application the Tickford head is not necessarily a better starting point, especially if its been decked/shaved. You're just pissing money away for wank factor. Much better to focus on getting any other casting tarted up with a decent port job by someone who actually knows what they are doing and can prove their results on a flow bench. Unless you get that tested how do you know what you've paid for? 6BOOST has reccomended to many people to hunt down an early EA CFI head and remove the swirl chamber for the greatest chamber volume. Others like GMDESTROYA have had more success with AU cast heads in getting higher flow rates. Its up to you what you want to spend and what you want to achieve. Personally i would favour the later cast heads with more attention paid to tuning in place of lower chamber volume for lower comp....just select the right dish piston to accomodate it.

ROD LENGTH: The whole debate about the 6 inch rod combo is really neither here nor there....you are only going to gain a slight increase in max rpm. I wouldn't base a choice on rod length.

ROD STRENGTH: pffft they are all stock rods. I don't care if you are talking about XR6t rods or LPG rods which are THE SAME THING only the XR6t rod has a floating pin. The weak points are going to be the bolts. ARP don't do a metric bolt. Maybe SPS do? But my machinist has found that a stock rod can be reamed for ARP bolts from an AMC Rambler. In any case you are better off going to the after market for some big H beams.

PISTONS: Next up from this would be looking at piston choice. ACL Race series....yeah sounds good, pity they are a s**t piston. Spend the money on something else. There are plenty of aftermarket piston and rod combos for the XR6t now. Spend the money once.

CRANK: Suprised nobody mentioned this one. EF and EL have a fully counterweighted crank. Others do not. However the aforementioned crank support AKA "CRANK GIRDLE" of the AU is a worthy consideration. I would trust an AU bottom end over any other.

MANIFOLD: BBM does make a difference even in boosted applications, well worth considering and yes Gas Research fits straight on.

Your Supercharger location has to be factored in. I have no idea where you want to fit it but you may have to sacrifice air con and i doubt it would fit with an ED style manifold. again look at BBM or possibly a custom plenum.

IGNITION/ENGINE MANAGEMENT: Ok if you keep a stock ecu you can probably get away with 6 pounds. Just have a look at your ignition options to back off the timing a bit. No idea how much the M90 can feasibly and reliably run.

Hope this helps..... keep me posted and if you have any particular questions, shoot me a pm.
Aaron

thankyou heaps for that info aarron. i am thinking of just going an eb-ed block and head for simple fit etc. as said before no-one has ever heard of a crank failing because of not having the AU's extra support. i would like to rebuild an engine before going S/C simply because my current engine is tired to can kill two birds with one stone. I will be getting ARP rod bolts fitted to my stock rods- the machinest knows how (302 bolts i think). what is involved to prep my rods? realisticaly this should handle 250rwkw reliably?

oh also i have been told for this much power (250rwkw) that forged pistons are not needed. was told that your clearances etc are up the creek when cold due to forged pistons expanding etc. remember i want this engine to RELIABLY handle 250rwkw.

Rod length and strength do come in to play. Im wouldnt say go for a 6" rod for more rpm - just for more piston choice if your not going for ACL's (which have shown time and time again that they are up to the task). Fact is, if you go for a 5.88" rod and want forged pistons then good luck finding them. Go a 6" rod and your fine.

And according to others on this forum xr6t did not get floating pins - only the F6 did. In either case Ive seen these stock rods pull 600rwhp oh the dyno, and the top 3 turbo 6's I know of (all 400rwkw+) are using factory rods.

few quotes from the forum...







What makes them a s**t piston?

more quotes...







EF has a 12 counterweight crank, EL has 8.



yeah the BBM is the best they have, but unfortunately the BBM mechanism doesnt give any gains in forded induction.

I would still experiment with the supercharger location to be sure it will work before spending one cent on a de-comp engine build. I made that mistake with a 250 crossflow and never got around to the turbo so essentially i had an excellent engine with low compression....

Even if you can just get a loan of a charger to dummy it up and identify any fitment issues and tackle the bracketry.

btw i just saw you are in Geelong.... i'm from Little River. Go speak to John at Johnny Dyno engines in Edol St Nth Geelong. Its where i usually get all my stuff done and is the reference point for the ARP bolts. The blokes at North Geelong Engine Reconditioners are top guys too.

Aaron

yer i have spoken to those guys. ur info is very helpful but do you realise there are vortec blower kits already available for ed? so i already know a blower will fit. any other input guys?

was thinking of using my standard rods with arp rod bolts. what needs to be done to the rods for prepping? or would it be better to go for some prepped BA egas rods with arp bolts? much stronger?

Jesus, I wouldn't be suprised if this is jim and brendon mock in disguise lol, what do you guys do for a livin?