Engine builds suck.

[Skylar]

Hey,

I bought this S14SR a week ago or something and bought it knowing it needed a rebuild. I was hoping to just give it new bearings, check everything and reassemble. NOPE. We're assuming the injector in no.4 chose to slack off and make cyl. 4 run lean causing some sweet detonation. That lead to an exhaust valve saying goodbye to some of itself and the head couldn't stand all the mayhem and melted a little. That piece of the valve decided to hang around for a while in the combustion chamber chillin out and leaving some marks on the piston. No prob, got a new head BUT the bore's 2 thou out of round. This is where you guys come in, Has anything seen anything like this where a bore's distorted from detonation?

Onto fixing the problem. I really wanted to leave standard size pistons in but with the bore being that out of round(nissan specs bore ovaling to less than 0.6 thou), I really should go oversize. Nissan's oversize pistons are only available in 0.2mm over not the regular 0.5mm/20thou bigger. I don't want to do forged 86.5mm pistons as I don't need an 600hp motor and $$$. How do ya'll feel about putting in one 86.2mm piston and leaving the rest at stock? This way I can cut costs this time and still do 86.5mm on the next rebuild. Either that or reassemble with standard size piston in no. 4 and be prepared to tear it down in the next year or so and be a little down on power, not that I'm shooting for race wins or anything. Just a stupid street car.

Your thoughts?

[slide86]

bore and re sleeve??, i believe this is what was done on number 4 if my gze

should bring it back near to factory spec ready for a hone

[Skylar]

Woah! Why didn't my machinist tell me about this?!

Funny you brought that up as I was just reading about sleeving SR's, but for 90mm bore but didn't click that I could just sleeve to 86mm.

[munki]

find a in spec block perhaps or as slide86 said a re-sleeve?

[KENut]

Not many people will let you buy just one piston. Plus thats kinda dodgy

Why not just bore all 4 to 86.2mm? Would save hassle and cost later on.

[Nikkojoe]

Not many people will let you buy just one piston. Plus thats kinda dodgy

Why not just bore all 4 to 86.2mm? Would save hassle and cost later on.

Mainly for the fact that he wants to not spend a lot of money on a shitty nissan. If he needs/wants to later he will go 86.5mm on all 4.

It's just cause nissan do a mild oversize only. His current pistons are like 86.018 (no.2 size) and this will be 86.2mm.


IMO bore and re-sleeve. Chances of finding a good block for cheaper than the machine work seems to be hard

[Skylar]

Not many people will let you buy just one piston. Plus thats kinda dodgy



This is my dilemma. I know it's dodgey but it still seems alright to me since the motor will have the ring gaps set and have good compression on all cylinders. And it's not like i'm ruining the motor by doing one at 86.2. I can always do 86.5 later.

On another note, it took me a few months to find this current motor and dude still wanted 300 for this motor with damaged head. Nissan world seems to have crazy pricing compared to here. One bloke wanted 450 for an S13SR block and crank. Good news is I found a block last night so going to pick it up and take to the machinist and have him check it on the bore gauge. If this block is no good either then I'll talk to machinist about sleeving.

[KE70]

It's good that you found a new block but I wouldn't advise you using one different piston unless its the same weight as the rest, balance issues?

failing that you could just get a custom carved piston made from wood? lol

[slydar]

i wouldnt bother with the engine at all. start again.

[Skylar]

I appreciate your input but can you elaborate as to why you said that. Is the block damaged beyond use?

KE70: I asked the machinist about the different weight of the bigger piston and he said it would be fine.

[ke70dave]

i would be very wary of using different weight pistons. and i would be very wary of an engine builder that is ok with the idea...

the thing i would be worried about is the different forces on your crank, i think it would cause the whole engine to become unbalanced, which it will jsut rattle itself to peices.

to be honest im kinda with slyder, you may be better off buying another block that you can reco. try your luck again.

[toygt]

300zx vg30dett std pistons are 1mm oversize for sr20det and are easy to get as you'll get four out of a blowen motor
and takes it nearly 2.1

i have some i could sell i'm wanting 100 kiwi for them plus freight

[FAST EDDIE]

good turbo blocks are hard to come by thats why they are so expensive, single pistons on teh other hand shouldnt be my engine builder has heeps because most people when rebuilding will put forgies in. look around

[slydar]

usually the cost of machining is a lot anyway. without knowing the history of the engine, youve already found its pretty fucked and been through a bit. you could end up spending a lot more money.

someone mentioned good turbo sr blocks are expensive. if thats the case then maybe its worth persevering. but thats a bit different than a 4A.

[Skylar]

The block is well useable, I just have to bore it to 86.2/86.5/87/sleeve for 90mm which is the problem. If I could get a set of pistons and rings for 200 bucks like a 4a, i woulda bored it without thinking about it. For 86.2 it's $820 for 4 pistons and rings and 980 for 86.5/87 forgies. Then bore+hone on top.
The block is pretty clean inside and water pump openings have no pitting/corrosion.

New block has a thou of wear but is round and "much better than your other block".
Eddie, feel like getting me a piston or the number of your engine builder? I need a 54C (GTiR/S14) in grade 2 or 3. I'll give a few workshops around here a call to see if anyone has one. I can get another piston new from Nissan but it's $125.

Looking into this VG30 piston business though.

[munki]

looked to the US for piston sets?

[FAST EDDIE]

lewis engines man

[--Redwork--]

Holly CRAP.. 980 for forgies.. Where the hell are you shopping....???
Friend buildt his SR for $1700 in parts.. JE pistons Eagle rods Tomie HG ARP Head Studs ect..
Sounds like you getting ripped hard man..

And sleeving is EXPENSIVE.. I doubt a machinist will sleeve a SR block the way they do old cast iron engines..
You said you were looking at the 90mm sleeves the other day.. You realise that it there's not many ppl that can install those sleeves in Oz as lots of ppl have tried but the sleeve moves and fucks the engine..

Just over bore it and fit some Forgies.. Aries pistons are cheap as if you look around... Shouldn't be much more than 550 for a set.

[Skylar]

Eddie, Cheers. Will give them a call on monday.

munki, where am I looking? Looked at Enjuku, full-race, p2m, summit, anyone else I should be looking at in particular?

Yeah, I know 980 is way too much. Spoolimports seem to have a decent deal on rod+pistons and rebuild packages.

I wasn't really looking into doing 90mm. Thread about it popped up on the local S-chassis forum so I looked at it. There does seem to be guy who knows how to sleeve motors though.

As much as I want to get pistons, if I do pistons then I'll do rods as well and costs spiral out of control.

Currently, I'm going with getting a piston for the new block and hone + re-ring, for now. Probably build something again later, for revs.

[--Redwork--]

Doing the rods really isn't needed..

Pistons a Good Head Gasket, eg tomie or Cosworth ARP head studs.. Thats ALL the parts required for a strong bottum end.. Everything else ppl tell you that you NEED is just BS..
You not bulding a 600hp drag car.. rods, bigger oil pumps, mains studs ect are simply not required..
There are so much BS floating around. Its annoying.. There is a comon rumor that SR blocks arn't much good over 400hp. TOTAL BS.. I have a friend who's car make 600hp atw through a 5500rpm auto.. EG MASSIVE hp loss and has done for years on a stock block that is still good.. His brothers car made 440atw with only minor work pistons/rods/HG/Studs.. no cams. no trick head work. No fansy secret tricks.. On 98 pump fuel.

[Skylar]

I don't mean to sound arrogant but since you know enough about the SR, where's the limit of the stock S14SR rods in terms of revs? Any preference of forged piston brands?

[--Redwork--]

Most SR's don;t make much power over 7500 unless they're stupid HP engines.. your usuall small cams and 2871 sized turbo SR will only ever need to rev to 7500 at most.. Stock rods are fine for this...

And its revs that has more of an effect on rods than power... So keeps the revs safe and your engine will live long and happy..

Pistons.. I use JE in my engine because they have the valve reliefs in then where almost all others don't//
But almost all of the affter marcket pistons are fine... Cp. Aries. Wiseco ACL.. all will do the job fine.. Just the prive varries..
I saw a sponser on NS selling JE's for under $600 a set the other day..
Hit up SR-NRG or STR180E on NS... they both know lost about SR's.. especially SR-NRG,, he deals with SR almost exclusivly.

[Skylar]

You dodged the first question like a politician and didn't really answer it. haha.

I know revs put strain on the rods and that it'll be happy at factory rev-limit and live longer but 7500rpm sounds boring. Turbo I have is plenty big and power should stay up there for a little more after peak power. I seen a few SR's revved to 9k but unsure if they had built motors or not. Probably did.

[--Redwork--]

To RELIABLY push past 8000rpm regularly you would fit rods...
But you can have a big turbo and still not need big revs.. The heads/cams don't flow well enough to support big RPM..
My friends car I mentioned with 600+ whp doesn't turn his much over 8000 and my own old NA race car made no difference in times when I shifted at 8000 or 8800...
End of the Day SR's don't like to rev really hard... Reguardless of what parts you fit... Even Josh Cootes mentall 180 drift car doesn't turn his past 8000 so I doubt anyone with a mild engine would ever need to rev harder than that unless they were trying to break it on purpose..

And none of this has touched on the fact that SR's love to damage valve train components at sustained high rpm without lots of money being spent..
But this too can be avoided by NOT REVING PAST FACTORY REDLINE..

[Skylar]

Last few questions.

Your NA race car, stock block or built?

When you say high rpm and reliable valvetrain stuffs, are you talking just solids or solids combined with Naprec rockers or shaft mounted rockers ala VE head? HLA's will survive 8.5k, the JIC S15 was running to 9k on HLA's but I wouldn't feel comfortable revving that high on hydros.

[--Redwork--]

My race engine was Stock SR20ve pistons. Eagle rods. stock block and crank. Head was heavily ported with solid lifters and 314deg cams.

Aftermarket rocker arms arn't needed.. I don't know a single person who's used aything other than stock factory rockers...
I personally don't trust HLA at all...
The cost of converting to solids is waay cheaper than rebuiilding your head when a rocker fails from valve float..
And its seems alot of ppl don't know this but the STOCK lifters can be converted to solids. no need to spend epic dollars buying a tomie solid kit.

[Skylar]

Yeah, I'm measuring out my 2 sets of rockers + the 5 or so in the S13SR head I got to establish a baseline of what the solid piece needs to be and what to do in terms of shims whether it be tomei, HKS or mattback style.

Which solids did you use?

[--Redwork--]

Which solids.???
I used the stock HLA.. they get dissasembled, the hydralic component is modified/removed (not sure) so its solid and then reasembled and shimmed to the right heights like a normal Solid lifter..

[Skylar]

That's tomei style. They're the only one that do solids that way. All the others adjust clearance at the lifter pivot. Did you get the right clearances using standard size Nissan shims? I didn't think you could, which is why tomei sell their own size shims.

The hydro piece in your solids were probably removed but they coulda left them in to reduce the amount of metal needed in the solid piece but that's me being real picky and trying to reduce production costs.

[--Redwork--]

I have no idea how they went about shimming it... I never asked..
I just gave my head to them and It came back all done.. I was super happy just to ba able to screw the engine together finally and never thought to ask exactly how they went about doing it..