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Hey guys, finally got everything I need to start putting this thing together. One problem though, I started taking apart the rb30 and when I took the head of, there was signs of a blown HG and rust in the bores. That scraps my original plan to use stock internals and it looks like someone cracked a bunch of raw eggs in the rad and this shit is all through out the block.

My plan now is to get the block acid dipped, decked and honed and then put it back together again. I cant afford forgies so I was wondering what would be the best upgrade to do internally? like should I go with upgraded pistons? or stronger rods instead?

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if you have a running engine in the car currently, save for the forged pistons.

may as well do it while its all apart.

if you need it, find another 30 bottom end in better condition and use that for now.

will probably end up cheaper then the machine work.

and slowly build the 2nd motor on the side.

Have a look at simons14's car. I think he is at over 400rwkw on e85 on untouched bottom end, and definitely gives it a hard time. Kinda makes it hard to justify a rebuild! he has a build thread.

Edited by superben

OK so my mind keeps changing with this thing lol. I called an engine reco place and they told me to clean it its going to cost me $60 and to get it decked $88. They will also check if it needs a rehone.

I think I might just freshen up the bottom end with new rings and bearings and save some dosh for a good clutch.

If your building for a track car, you need at minimum to blueprint the motor is your half serious about doing something to it and helping it survive.

At minimum it will need to be decked, honed maybe bored, and possibly have the crank bore alignbored, before we go into pistons and bearings, let alone rods.

With a standard rebuild at minimum you need new rings, bearings, and if the bores are good just a hone.

There is not much difference in work if the rust is not deep as a hone will clean it out, either way you need to acid dip your block to clean it no matter how clean or dirty it is, one speck of grit and its all over.

All in all if it adds up to too much and you dont want to spend, buy a VL Runner and leave it alone, hopefully it will last long enough till you save up a bit.

If you do want to change something on a stock bottom end in a track car, concentrate on oil pump, a bigger sump and breathers and if funds allow look at rod bolts and pistons over rods if short on cash in the order listed.

Yeah I already have an N1 oil and water pump but when I saw the shit that was in the block, it made me think that even if I did buy a running rb30 I dont know what the previous owner has dumped in it. Im not going to bolt brand new stuff on an engine based on what the guy I buy it off tells me. The guy I bought this engine from told me it had under 200,000k on it and he only took it out of his VL because he bought an Rb25 for it. I don't think so.

I always thought getting it honed and bored were the same thing? If it needs it ill get it done and ill ask the the shop what else I need to do.

Still tearing this thing down and so far im feeling pretty good about putting it back together. I have the work shop manual and its helped me out a ton.

And yeah, mainly track car. I would love to see 500hp from this thing but ill be happy with what ever the tuner does as he would know best.

Edited by Gameboy

Honing takes a little metal off, it does make the cylinder slightly larger. what it basically does is to produce a new finish on the bore for the rings to bed into, new rings need a particular finish to bed in properly.

Bore is to make the cylinder larger, this guaranty's you will need new pistons, its used when the old bore finish is too worn or out of round so they need to go wider, this is done by boring and then a hone finish is applied afterwards for a ring bed in and seal.

You can just hone a old bore and use the old pistons if the cylinders are still in reasonable condition, a little bit of rust can be taken out however the person doing the job needs to check your piston skirt width and then finished bore diameter and then calculate if your still OK with clearances, too much bore clearance leads to piston slap and compression loss.

Any machinist workshop can just look at the block, see the condition of the bores, measure them up and then measure your pistons and give you a idea if you need just a hone or a bore and new pistons.

Edited by GTRPSI

If it were I. I would do as The Mafia said. In the long run will last longer and will give you a better compression ratio. If planning on running e85 you want atleast 9.1 comp IMO. Save a little longer.

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