Just wondering what people opinions were on standard vs eagle vs XYZ?

Limitations, build quality etc..

Cheers

You probably need to tell us what your ultimate goal is, ie, what boost you want to run and whether you are going for a standard or forged rebuild.

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And budget Dan

Arrow make nice rods as does Carillo but neither come cheap

FWIW if you use Eagle get them weighed. There's a lot of talk about their crankshaft being poorly balanced so I wouldn't want to fit their stuff without checking...

I believe ultimate goal is high 300 / low 400 BHP. Forged build being done by TB developments. Tim is suggesting Eagle rods for the higher end of the power range, or standard otherwise.

My own thoughts:
I've never heard of either conrod or crank failure on these cars. There are plenty of forged engines out there running standard rods, including one I heard of where the builder had stamped markings in with a cold chisel - that engine was running quite a bit of power and driven very hard for a lot of miles.
Looking at the physics - increasing RPM will increase both tension and compression stress on the rods in order to accelerate the pistons up & down faster. Increasing boost / torque will only increase the compression stress.
Standard rods are an H shape which is very strong in compression. Unless I'm mistaken, Eagle rods are flat, therfore relying on stronger material properties.

I would personally question whether Eagle rods will offer any significant gain for an engine which is only going up to standard RPM.

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You goals would appear similar to mine. If I were doing it all again I think I would go with standard rods.

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1996 ST205 UK

Chris has summed it up well. For now I'll be keeping standard turbo and going for the same 330-350 bhp. However in the name of future proofing to an "end goal" I'd like the engine good for high 300 - low 400s.

Boost for now will be 1.2 / 1.3bar depending on further research/mapping. The turbo Tim would recommend for my end goal was a 3071r if I recall correctly which made Andycaca 350bhp @ 1 bar. Point being I don't think I'd be pushing more then 1.5 - 1.6bar? to reach that figure with said turbo?

The car is my daily driver but also gets some abuse on weekends on track and autotests.

Think I may end up with standard rods with ARPs in then.

Thanks for input thus far.

Don't think i've been on here for a while but seeing this thread interests me I thought I'd join in.

Not sure if you mean XYZ as "anything else" but there is actually a company called XYZ that does make conrods lol, there cheap Chinese rubbish and they also do suspension and big brake kits, few UK traders selling there rubbish as there own but thats another story. Anyway conrods

The best off the shelf conrod i've seen or used is Pauter, there stupidly strong but alot of the time you just don't need that strength setup as there very expensive. The best conrod i've ever used was a forged alluminum custom made unit i had done for our 900+bhp drag car about 4 years back where made by BME, extremely light and extremely strong and guess what, extrmely expensive haha. for people who don't know BME make all the conrods for the 9000bhp topfuel rail drag cars. Anyway long story short we threw a big end racing at 9500rpm and it chewed up a rod, In desperation to make an event we threw a set of eagle rods in there as there were a used set sitting around. They handled the racing fine at that event, and it became abit of a test to keep using those conrods until they broke just for test basis's. Well those conrods were still being used after multiple rebuilds when we retired the car 3 years ago. so think thats testimony to there build quality.

I recommended eagle conrods over 400bhp because i've seen a few standard conrods bend over that. Obviously you need to fit some good ARP bolts to the rods but fitting ARP's isn't just a case of dropping them straight in, you need to reem the stud holes properly and then resize the big end as the ARP torque turns them slightly oval, so by the time you've done this its only about £100 extra to use eagles. Although this has already been done for your build, but like i said if you wanted to go for additional conrods on the build i'd be happy to absorb the cost and move to a full rod if you wanted.

Mainly replying to stick up for eagle conrods haha.

With engine building nothing it taken for granted, so everything is weight balanced to 1/3 gram at my shop and never had an issue. In the past 3-4 years i've been building a forged 3sgte of some description 1 ever 10 days for the past 7 months straight, and was busier the 2 years before that. Estimate over 350+ engines over the past 3-4 years with 70% running eagle rods, everything from road cars to flat out track, drag and a couple of 200+mph cars never had a rod failure or issue. So i rarely use anything else when it comes to uprated conrods unless a customer says they want something else.

One thing to note is there so alot of copies about at the moment i've seen springing up. A customer supplied me a set of these Ebay rods, they look idential but measurements and balance was all over the place so that should be noted.

with a few of my engines i've done the GT3071r with a small 0.63 ar exhaust housing was making 450bhp at 1.5bar boost pressure and very fast spool. This is perfect for your goals i believe. If you want more i can certainly supply a GT3076r setup which i normally see 500-530bhp without going silly on the boost

Tim
TB Developments

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Hi Tim, good to see you on here.

You mentioned experience of standard conrods bending at over 400bhp. Were the engines concerned running higher rpm? And what sort of boost?

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If at first you don't suck seed, try drier grain.

Thanks for the input Tim. No, I was not aware XYZ were a real company lol, sounds a bit generic




I'll be back one day for the GT3071r. Low 400's is fine thanks, dont tempt me for more lol.

Wasn't trying to knock them. Just pointing out that they do seem to have some balance issues with 4G63 stroker cranks which would make me want to double check the matching of their conrods. As you say this should be part of a professional rebuild anyway so it's not a major deal. More a point of interest

In an engine that might spend quite some time sitting at the redline I would consider rods personally. The weight reduction should relieve quite a bit of stress from the rod bolts

Can't say I'd really lose sleep one way or t'other though

i will admit i have only come across this twice, one was running 380bhp and had a boost spike, stop redline. all 4 were badly bent almost looked like a bore lock so not totally convinced on that one but no evidence of a bore lock. the other one was 450bhp and again normal redline 1.5bar boost, was used heavily and had ARP bolts fitted and developed a little end rattle, took it apart and there was a slight twist on all 4 pistons and heavy skirt rubbing, and find again all 4 were very slightly bent and twisted but nothing like the first one.

Tim
TB Developments

ps animal66, the turbo kits i do produce are the same from for all the GT30 and GT35 range anyway so 700bhp GT3582r is also on that list

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lol i was just sharing my own personal experiences with them. while talking to dan about this he had said that the eagles weren't liked on the DC, so not overly bigging them up just saying i've not had any bad experiences and couldn't see any point of going to say pauter for triple the cost

Tim
TB Developments

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Another vote here for the Eagles... stock rods can be bent!

As for weights, I recall that my eagles were with in 1g between all 4 rods...

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Kris
95 ST205 - slept for 10 years, now waking up...
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Turbocharging - the replacement for displacement

I think there quality control on the eagles is 3 gram between rods, but when I use these in a build everything including the rods is balanced within 1/3 gram

Tim
TB Developments

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