PistonHeads.com Forum

ZRP Forged Conrods

Author
Discussion

Tango13

4,854 posts

100 months

Thursday 29th December 2016
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Most of the blokes I've worked with in engineering have always referred to 'Verniers' as 'very nears' and only used them for checking they're not mis-reading a micrometer by half a turn.

One of these with a rod anvil would be a far more useful piece of equipment.

https://www.cromwell.co.uk/shop/measuring-and-test...






Mignon

265 posts

13 months

Thursday 29th December 2016
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227bhp said:
Seriously, thanks for taking the time to post, i'm still chuckling from the other thread linked to too hehe
Yeah, that bloke Pumaracing eh? He had a right pop at the OP on page 2. They should have banned him, lol.

Boosted LS1

16,600 posts

184 months

Friday 30th December 2016
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Definately, what an utter tool.

Edited by Boosted LS1 on Friday 30th December 09:53

PeterBurgess

560 posts

70 months

Tuesday 3rd January
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As promised some pics of one of the MGB cheapy rods.


Pics 1 and 2 point of max ovality each side of rod.





Pic 1



pic 2









cheap rod, each side different thickness.



Robson/Farndon rod sections are the same.

Peter




Blackened areas where oil has got behind bearing and burned because of ovality. Shiny bit each side of cap split only area on size.

Apologies for edits, the pics were all over the place!


Edited by PeterBurgess on Tuesday 3rd January 15:12


Edited by PeterBurgess on Tuesday 3rd January 15:14


Edited by PeterBurgess on Tuesday 3rd January 15:15

227bhp

5,788 posts

52 months

Wednesday 8th February
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Op never came back.....

Some pics of the cheapo rods, can't really find fault with them, though I can see a bit of a different design feature to the ones in the previous post.
All within .2g of each other and everything centralised, at least they label the caps unlike some others. I remember a thread from just over a year ago now where the poster may have got them mixed up or wrong way round...








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e21Mark

Original Poster:

9,490 posts

97 months

Wednesday 8th February
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Apologies - missed replies.

Engine builder checked rods and although not overly impressed he did say they were within tolerance. He also said they were pretty heavy. Anyway, am just waiting to get the newly built engine back now.

stevieturbo

12,711 posts

171 months

Wednesday 8th February
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At Autosport there were a few places with rods, was surprised ZRP werent there though.

Some of the nicest visually were from Italian RP

They werent the cheapest, but certainly not that expensive either and visually very nice.

http://www.italianrp.it/indexeng.html

Wiseco also had some nice looking rods...but holy feck they were heavy.

227bhp

5,788 posts

52 months

Wednesday 8th February
quotequote all
stevieturbo said:
At Autosport there were a few places with rods, was surprised ZRP werent there though.

Some of the nicest visually were from Italian RP

They werent the cheapest, but certainly not that expensive either and visually very nice.

http://www.italianrp.it/indexeng.html

Wiseco also had some nice looking rods...but holy feck they were heavy.
Thanks for the link, some good parts in there, it's a shame there are no weights in the catalogue. Probably ZRP have no need to go any more....
What did you think to Autosport? Everyone you speak to says it's not that good anymore and it gets smaller every year. I didn't go as it's our busiest time of the year so couldn't really take a day off and with a few exceptions it is often the same old stands every year. I was talking to the ARP rep the other day and he said he'd heard nothing but good things about ZRP too.

e21Mark

Original Poster:

9,490 posts

97 months

Wednesday 8th February
quotequote all
Are forged rods always going to be heavier?

Also, how is the added weight likely to impact on running/performance? (If at all)

Boosted LS1

16,600 posts

184 months

Wednesday 8th February
quotequote all
stevieturbo said:
At Autosport there were a few places with rods, was surprised ZRP werent there though.

Some of the nicest visually were from Italian RP

They werent the cheapest, but certainly not that expensive either and visually very nice.

http://www.italianrp.it/indexeng.html

Wiseco also had some nice looking rods...but holy feck they were heavy.
I only pick them up one at a time ;-)

stevieturbo

12,711 posts

171 months

Wednesday 8th February
quotequote all
227bhp said:
Thanks for the link, some good parts in there, it's a shame there are no weights in the catalogue. Probably ZRP have no need to go any more....
What did you think to Autosport? Everyone you speak to says it's not that good anymore and it gets smaller every year. I didn't go as it's our busiest time of the year so couldn't really take a day off and with a few exceptions it is often the same old stands every year. I was talking to the ARP rep the other day and he said he'd heard nothing but good things about ZRP too.
I thought it was very good, but then it depends what the expectations are before going. TBH if I was to go next year I'd just go Thursday and Friday, as I have far less interest in the other ste and the more interesting stuff is on the trade days.

Some rod pics from the show.

The Subaru Wiseco's were something insane like 610g, the Italians around 530 I think. Carillos for comparison are around 535g too.
Even in the hand, the Wiseco's were very noticeably heavy compared to anything else.


https://postimg.org/gallery/31ttbzlrg/














photo host

227bhp

5,788 posts

52 months

Wednesday 8th February
quotequote all
e21Mark said:
Are forged rods always going to be heavier?

Also, how is the added weight likely to impact on running/performance? (If at all)
Heavier than what? Presumably OE...
There is no rule, it depends on how advanced the originals were and well, how cleverly designed the new ones are too, as I think I pointed out earlier the ones we fit on 80s/90s stuff are a big improvement on OE, but you're going to have to go some way to beat a top end late model Honda or similar rod. It's down to design and material strength, the more expensive you go generally the better they get.
Scales are cheap on Ebay, get busy.
They are both forged btw, lol, you wouldn't have a cast rod, billet maybe....

Boosted LS1

16,600 posts

184 months

Thursday 9th February
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^ That said, I recently opened up a 1974 Pontiac 400 engine. It had cast rods inside. I thought they'd been phased out in the 50'ies.

227bhp

5,788 posts

52 months

Thursday 9th February
quotequote all
Boosted LS1 said:
^ That said, I recently opened up a 1974 Pontiac 400 engine. It had cast rods inside. I thought they'd been phased out in the 50'ies.
Cast rods yikes

We had a modern engine apart the other day and it was interesting how they'd managed to make sure each cap went back where it came from. I don't know what it's called, or how they do it, but the mating surfaces look like a piece of cast which has been snapped (like the surface of a rough stone), clever stuff.

stevieturbo

12,711 posts

171 months

Thursday 9th February
quotequote all
227bhp said:
Cast rods yikes

We had a modern engine apart the other day and it was interesting how they'd managed to make sure each cap went back where it came from. I don't know what it's called, or how they do it, but the mating surfaces look like a piece of cast which has been snapped (like the surface of a rough stone), clever stuff.
As the name implies...cracked cap.

Very common these days

What is ore surprising is this video would imply that if you buy a brand new rod from a dealer..it is uncracked. Either that or the new halves were securely mated together ( which is part of the reason for doing the cracked cap, if you get them to fret or move something has went badly wrong !! )

https://www.youtube.com/watch?v=UaatYvC6T-w


https://www.youtube.com/watch?v=QlVrDJBiqd4

Boosted LS1

16,600 posts

184 months

Thursday 9th February
quotequote all
227bhp said:
Boosted LS1 said:
^ That said, I recently opened up a 1974 Pontiac 400 engine. It had cast rods inside. I thought they'd been phased out in the 50'ies.
Cast rods yikes

We had a modern engine apart the other day and it was interesting how they'd managed to make sure each cap went back where it came from. I don't know what it's called, or how they do it, but the mating surfaces look like a piece of cast which has been snapped (like the surface of a rough stone), clever stuff.
Chevrolet have been doing that since 1998 at least. I first came across it on the ls1 engines. They also use powdered metal forgings. The rods are a near identical weight. Clever stuff.

rachaeljf

6 posts

156 months

Thursday 27th July
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Hello all, a question for buyers of Maxpeeding rods - did your rods have machining marks like these?

227bhp

5,788 posts

52 months

Thursday 27th July
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Yes that's normal for Chinese rods, I think it's one of those features which sets them apart from the top end stuff.
Whilst it isn't a great finish it doesn't seem to do any harm.

rachaeljf

6 posts

156 months

Thursday 27th July
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Really? That's remarkable. I see stress raisers there that could severely curtail the life of these rods. Thanks for the info, much obliged!

227bhp

5,788 posts

52 months

Thursday 27th July
quotequote all
rachaeljf said:
Really? That's remarkable. I see stress raisers there that could severely curtail the life of these rods. Thanks for the info, much obliged!
If they were failing there it would be an issue, but they don't. Most of the time they're over specified (in terms of design and material) so a bit of poor finishing like that has no effect lthough it really depends on the end use.