Nisif

Last week I spun a rod bearing in my stock block ls turbo setup. The engine was completely stock except for arp head studs. I managed 50,000 hard miles on the set up laying down 260 whp/240 tq on 14 psi with a t3/t4 50 trim.

I'd like to keep the same turbo setup and the stock head but rebuild the bottom end and increase the boost to obtain close to 350 whp.

I'd like to shoot for at least another 50,000 miles after the rebuild. I'm looking for recommendations on the build. I feel confident running on stock sleeves at that hp level with a good tune but am undecided about the pistons and rods. I'm planning on keeping the bore at 81mm, possibly 81.5 if an overbore is needed.

Do I need forged pistons and rods? Not sure if I can get away with shot-peening the stock rods and upgrading to arp rod bolts. And whether or not the stock cast pistons will blow ringlands at that power level...

Are they're aftermarket cast pistons available that will hold up to the power level?

phaphon

eagle rods amd cp pistons

Spawne32

iTrader: (3)

manley rods and supertech pistons

DDTECH

What's your budget.

wantboost

iTrader: (2)

i've always tried to use manley rods and cp pistons where possible on most of my builds... can't beat the quality and attention to detail that Manley puts into their products

MR.johnson

I ran the cheap supertech pistons to over 600 HP with eagles. Still looked like new when I pulled them out.

dcmatt

iTrader: (7)

Let your budget dictate. If you can afford it then go for it. That way when you're ready to squeeze a lil more out of it you'll be able to with the forged internals. I have to say that 50k on stock internals is pretty good.

blackeg

yeah 50k is solid. 81.5 is probably going to come recommended as there could be some out of round or something after that many miles of boosting it up

Ls vtec turbo

How do I get to a ls vtec turbo forum new to this website

Ls vtec turbo

need to talk to someone that know a lot about them

dcmatt

iTrader: (7)

nevermind realized you're not the OP. make your own thread with your question in this forum if its forced induction related. if not try all motor forum.

Nisif

I agree, I definately got my money's worth out of the stock engine. A few cross-country trips and countless passes at the drag way amongst its lifespan made it an interesting budget build.

I can afford to build the motor to the max but I don't want an all-out drag car. The whole concept of the car is that it's still a budget build and I don't want much more than 350whp out of it. I'm concerned after 350whp I'm going to worry a lot more about drivetrain problems, ie: replacing transmissions, cv axles, etc.

I'd like to see an easy 11.5 sec pass with 350whp but still own a remotely practical street car. I ran a best of 12.3 at 110mph with slicks so 11s shouldn't be an issue with nearly 90 more addition hp.

With that said: I'm considering the following, And would like to stick below a $1000 rebuild budget because I think it can be done with all machining work and new parts, bearings, head gasket with a stock head:


1) Running aftermarket cast pistons. I've looked into Nippon and YCP aftermarket cast pistons. I'd prefer cast if they can retain the power (which I've heard that they can) because they're cheaper ($200 or less per set of 4) and retain characteristics of a oem engine, ie: no knock upon start ups, less oil consumption (dependent on tolerances), tighter piston to wall clearances.

Link(81.5mm, YCP brand preferred amongst what I've researched compared to Nippons)
>>>http://www.ebay.com/itm/YCP-Honda-Ci...7dbfba&vxp=mtr

Link (81mm, Nippon brand, ideal bore size if I can run them after checking cylinder out of round, slightly cheaper than the above)
>>>http://www.ebay.com/itm/Nippon-Racin...8f16d7&vxp=mtr



2) Buying Eagle Rods. Safe bet and affordable. A little heavier than stock rods but I don't plan to rev the **** out of the engine. 7200 rpms max, which it won't make power at that level with a stock head and cams but I may need to carry out a gear or two to make a good pass at the track. Found a new set online for $285 shipped.

Link (hopefully these aren't counterfeit...suggestions needed)
>>>http://www.ebay.com/itm/230843336937...84.m1438.l2649


So far I ordered a set of ACL bearings. Upon disassembly, 3 of the 4 rod bearings have "green" thickness sized oem bearings. And 3 main bearings are green, the other 2 are brown. Whichever journals that don't lie in spec after the rebuild (after measurements) with standard acl bearings I'll buy the approriate sized thickness OEM bearing.

I'm trying to find a store that offer a variety of different Nippon or YCP cast pistons. So far, I've only been able to find ebay sellers that offer a certain bore size or dome height that may or may not fit my needs for the build. I'm dropping the block off tomorrow at the machine shop and hopefully I can retain the stock 81mm bore size if the cylinder walls aren't too out of round.

dcmatt

iTrader: (7)

Some people have put down some respectable numbers with the nippon pistons. Most of what ive seen was with b16's though. GEN2LS did like 400 with the hi compression nippon's and E85. And I remember Nasty Garage saying hes built a few b16's in the 400+ range. both stock rods with arp rod bolts if im not mistaken. Probably better off going 81.5mm though. I'd have the machine shop measure before you make your decision. And really they should have your pistons in hand before starting machine work to make sure you get the proper P2W clearance. Are you still on a LS tranny? GSR tranny would have a lil better gearing for the track for sure. You may like the LS for daily duty though. How bad was the crank scored?

Nisif

If I can get away with running stock ls rods with upgraded arp rod bolts I would. Although B16s have a shorter rs ratio which puts less stress on the rods...I think I may be walking a fine line with ls bottom end with stock rods and expecting at least 50k miles at 350 whp.

And yes, I'm running a stock cable ls (ys1) trans. It peaks out now at the top of 4th in the quarter mile with 22" slicks but is very practical and affordable for a dd.

Sidenote: I'm actually rebuilding a spare high mileage bottom end block that doesn't have any damage or spun bearings with a clean unscathed crank. (should of metioned that earlier). The current bottom end with the spun rod bearing is still in the car. Haven't assesed the damage yet, but I didn't run it long after hearing the rod knock.

Nisif

A build or rather Re-build thread is always better with pics...

For viewing pleasure...dyno post of the original setup and a low-res cam phone vid of the stock block setup:



http://youtu.be/tE3aDNrZO1M

LightningTeg

That looks like fun. Dont worry about drivetrain until you get into the 500+ range

dcmatt

iTrader: (7)

Nice pass. Bigger slicks will get you a Lil more breathing room on the gearing. If your planning on keeping the head stock id look into arp rod bolts. With a stock head you wont be revving to the moon. Rpms is usually what kills rods. Eagles are alwYs a safe bet though if you can get em.

wantboost

iTrader: (2)

cast pistons... meh
some people have had good luck with them, others not... tune has to be conservative because cast pistons can't take knock like forged pistons.... nor very high cylinder pressures.. they crumble
go forged the first time and do it right

Nisif

I'm considering forged pistons now. I've read good review on Supertech pistons and they're relatively inexpensive...I can get a set for a little under $400. My only concern is that the lowest compression piston they offer yields 9.6:1 on a ls engine. I was shooting for more for around 9:1. It'll be tuned on 93 octane, but I'd like to play it on the safe side.

wantboost

iTrader: (2)

you'll be fine... thats not very high and you'll get better off boost performance and fuel mileage due to increased efficiency... ever point you drop in compression is like a 3% drop in efficiency

Nisif

I spoke to my tuner yesterday and he recommended no more than 9:1 compression ratio if I want a conservative tune on pump gas. I'll lose some out of boost response but I'd also like to stay on the lower side of cr in case I later install a b16 or gsr head which will increase compression at least a half point.

Nisif

I was content with the use I got out of it. Going with an 81.5 bore...saw the dyno numbers in your sig. What's your build setup?

wantboost

iTrader: (2)

If you're running 93 octane you could run up to 10:1 at your 300hp power goal without issue... you don't need to be THAT conservative... hell if you had really really god tune you could run up to 11.5:1, Tony The Tiger has done almost 400hp on 11.5:1 cr on pump gas without a problem