forged pistons recommendations

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androo007
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forged pistons recommendations

Post by androo007 »

Hi guys,

Looking at saving towards a build on engine, what are the most recommended pistons to use? I presume a bore out to 86.5 and compression of 8.5:1?

I've read rods aren't needed until circa 500bhp - not my plan.

Just intending on freshening engine up and putting in forged pistons for a reliable 1.2 bar :thumleft:

What's the expected average price for that would you say?

Cheers
Last edited by androo007 on Mon Jan 04, 2016 12:16 pm, edited 1 time in total.
abovetherim
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Re: forged pistons recommendations

Post by abovetherim »

Now I don't know much about turbos but why would you want to bore out the cylinders?? surely just a re hone and new rings would be better for reliability as the walls are thicker and therefore stronger. I could understand if you were trying to increase the capacity (or reduce the comp ratio) to increase potential power.

I'm not knocking here, i'm genuinely interested in pros and cons of this. I can understand wanting to have forged pistons to prevent ringland issues tho.
androo007
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Re: forged pistons recommendations

Post by androo007 »

I'm the same here....it seems to be the standard from what I see as often rings gone means a slight bore is needed from last scores etc but not sure if that's a minority or majority?

I guess the shopping list would be....

Pistons
Rings
Gasket set
Oil pump
Water pump
Cambelt kit

Is it worth going the bearings and journals whilst down there
?

V interested in labour costs.
ashley
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Re: forged pistons recommendations

Post by ashley »

Definitely keep your pistons as small a diameter as your block lets you get away with, if it does need a rebore- then hopefully you can get away with 86.25mm.

CP pistons are good, but there are plenty of very good makes out there- shop on price and compression ratio. 8.5:1.0 or 8.0:1.0, depending on the state of your head- but aim to keep squish as close to stock as possible.

Pistons will generally come with rings, so you'll need to hone the bores at the very least.

Have the crank measured and inspected, then depending on what you find it may / may not be worth a polish and new mains. Definitely new big ends, no reason not to while you have it all apart, and they take some abuse on these engines.

Oil pump: measure to make sure it's in spec, and not overly worn...if it's ok I wouldn't bother swapping it out (although others will say you have to for some reason).

New water pump, cam belt and idlers, and new gaskets all round...you'll obviously need a new head gasket as well...don't go thick on this (see keeping your squish as stock as possible).

You'll also want to swap in new crank shaft oil seals (the front is prone to leaking), but these should come as part of the engine gasket kit.

I wouldn't bother with rods unless you want to go mad, but it's worth using ARP rod bolts (for the price anyway), I'd also stick ARP head studs in while you're there (although not strictly needed for your plans).

Hope that helps some :thumleft:
C35Rob
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Re: forged pistons recommendations

Post by C35Rob »

ashley has said everything you need to know there..

afaik, wossner are the only company that offer 8:1 CR pistons "off the shelf" so, depending on your intended power goals/boost pressure they may be the ones best suited to you, as the likes of CP etc supply 9:1 as standard.. obviously you can get custom CR pistons machined should you want to pay for them.
EX MR2 owner, currently on a '00 Honda CBR600 Follow me on Instagram @c35rob
Ryan S
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Re: forged pistons recommendations

Post by Ryan S »

Can only go with what Ash has said already. My pistons are Carrillos, they come with chrome rings. I would buy new as well, a friend of mine bought pistons from a member on here (who had other members vouching for him) and there was loads of bits missing including the spec sheet. Compression ratio is up in the air. I suggested going 9:0:1 (which i have went with) and everybody lost their minds, Nathan Freke is going 10:5:1 and nobody bats an eyelid. With the quality of engine management and fuels these days higher c/r is absolutely fine. However, if you are keeping the stock ecu etc wouldn't recommend it, it'd be better to go 8:5:1.

Deffo change the oil pump. For the sake of £100 for a genuine Toyota one why wouldn't you? It's so much easier with the engine out. Same for the water pump. I'd freshen up the gaskets too. Full gasket set from Toyota is cheap (around £170 iirc)

Again, check crank tolerance and fit new big ends. I had mine polished just for the sake of it. :thumleft:

Renew as much stuff as you can afford to while the engine is out. Imagine how you'd feel knowing the engine needs to come out 6 months after you've been back on the road!

Good luck with it :)
C35Rob
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Re: forged pistons recommendations

Post by C35Rob »

sheppy wrote: Nathan Freke is going 10:5:1 and nobody bats an eyelid.


I assume he is going to be running C16 or E85 though, which changes the game slightly..
EX MR2 owner, currently on a '00 Honda CBR600 Follow me on Instagram @c35rob
Hez
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Re: forged pistons recommendations

Post by Hez »

http://www.imoc.co.uk/forums/viewtopic. ... 163cd08e75

Is the relevant, i myself went with 86mm cp pistons listed at 9.0:1 however will be 8.5:1 with the standard gasket.
Ryan S
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Re: forged pistons recommendations

Post by Ryan S »

Wise words from Greame, a very knowledgeable builder. Also, the info in that thread is very useful. Somebody should knowledge base that :thumleft:
Ryan S
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Re: forged pistons recommendations

Post by Ryan S »

Rob - East Coast Imports wrote:
sheppy wrote: Nathan Freke is going 10:5:1 and nobody bats an eyelid.


I assume he is going to be running C16 or E85 though, which changes the game slightly..


What was the C/R on his last car? I don't think that was running E85. I don't know much about the last car apart from the times it ran in all honesty though :(
gnzyza
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Re: forged pistons recommendations

Post by gnzyza »

Its probably worth putting up what your power goals are, running 1.2b on which turbo? If you already have a healthy engine being clever with temp and management will you actually need to go to the expense if a rebuild.
androo007
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Re: forged pistons recommendations

Post by androo007 »

Thanks a lot for the input here guys.

Looking to therefore buy:

Oil Pump: £95.34 - TCB
Water Pump: £78 - TCB
Gasket Set: Toyota - £166 - TCB
CP Pistons (86.5mm): £480 - Can't say without it going xxxx
Big end Bearings: (TCB?)
ARP Head Bolts: £153 - H-Tune

Any pointers on where's best and cheapest woudl be really helpful as its a minefield out there.

Cheers guys

PS: My current engine is on 86k, and i drive it very gently.... as much as I trust its reliability - ringland failure will be enevitable at some point. I'd like to keep the car forever if i can, so happy to invest in upgrading the vital areas. Plus then I can be happy about running it at optimum without fearing it going POP at any moment.

Plus forging a running car is a LOT cheaper than fixing a duff engine.
Last edited by androo007 on Thu Jan 07, 2016 12:45 pm, edited 3 times in total.
Ryan S
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Re: forged pistons recommendations

Post by Ryan S »

I bought all my bits from Hurley Racing except for the gasket kit as Hurley never had it in stock. I got that from TCB. Hurley were the best on price (and the best to deal with). The pistons I got from GTSChris but I see his site is down as he's "retired". So not sure what's going on there. :thumleft:

TCB couldn't tell me the difference between the mr2 rev3 and the GT4 st205 gaskets set despite there being a £60 price difference. I ordered the st205 one :lol:
androo007
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Re: forged pistons recommendations

Post by androo007 »

Cheers Shep, yeah i noticed GTS Chris has gone somewhere.

I can't find much on the hurley racing, is it because they just dont list everything on their site?

CP Pistons surprisingly hard to find... and everyone lists the 86..5 at 9.0:1?
C35Rob
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Re: forged pistons recommendations

Post by C35Rob »

I noticed chris had 'retired' too, he sold his drag car on ebay recently, last time I was at his unit (6 months ago?) He had his daily scooby, his impreza race car, his personal Ferrari 360, and another race car - a ginetta G50 iirc, so he wasn't doing too badly for himself by the looks of it. Maybe he did retire, maybe went into another line of work? Who knows....

I see this outfit


http://www.tuningdevelopments.co.uk/pro ... ts_id=2428

Do engine build kits, tbh ive not added it up to work out if it's cheaper than buying it piecemeal yourself, but it may be worthwhile to save the hassle of getting everything individually.
EX MR2 owner, currently on a '00 Honda CBR600 Follow me on Instagram @c35rob
androo007
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Re: forged pistons recommendations

Post by androo007 »

Not a bad shout, thanks Rob. Couple of things there….

Rods – didn’t intend on doing them really – plus I’ve seen some fitters refuse any warranty if using Eagle rods – interesting that! Plus only the higher kits have the oil pump and not a full gasket set…. Hmmmm.

I price it up at about £950 for parts (450 for pistons) which seems a lot cheaper.

Cant find the water pump anywhere either....
Ryan S
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Re: forged pistons recommendations

Post by Ryan S »

Sorry mate, I meant to mention that a lot of Hurleys stuff is on ebay. Just search for an oil pump and you'll find their shop, they have far more on ebay than their actual site. Also give them a phone if you can't see things you need, more often than not they actually have the parts in stock. As I said they are extremely helpful and have been the best on price, quality of items and customer service. My entire build has been parts from Hurley save for the exhaust, clutch and pistons which were all from GTSchris :) oh, and the gasket set but TCB were around the same price (for the st205 kit) from what i remember. TCB are fine but I didn't feel they were very knowledgeable from my phone conversations with them. :-s
Nic
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Re: forged pistons recommendations

Post by Nic »

androo007 wrote:Cant find the water pump anywhere either....


I recently bought an OE Toyota water pump from TCB for a good price.

http://www.tcbparts.co.uk/rads%20&%20cooling.htm
Nic
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MR2 Rev 3 GT Turbo
androo007
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Re: forged pistons recommendations

Post by androo007 »

Thanks Nic, Shep will use hurley as a comparison, nice one

Just the pistons to locate now.... :thumleft:
J-1
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Re: forged pistons recommendations

Post by J-1 »

Who supplies forged pistons and rods in the UK?
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