ls vtec turbo build questions

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Mr JDM

New Member
ok so i have a b18b1 bottom end with a stock 81mm bore and a b16a JDM head. i would LOVE to use my stock ls rods and pistons but i know that the weak point of the rods is the bolts. i have the option to go ARP rod bolts but then have to get the rods honed to compensate for the torque on the bolt. and the price of that is 150 from my machine shop. i also heard that the clearance on the pistons to the new heads valves is too close. so i was planning to go weisco pistons with a 9.5 -1 compression. is that too high? they are avaliable from 9- 9.6... I also was curious to what ecu setup i should run. my local tuner does not tune on hondata which is gay.. pics and more questions will be posted soon!
 
that compression is not too high, but keep in mind that is just static compression. that is not factoring in the difference in heads

when they sell you a set of pistons, they assume that you are using the stock head and not that of a vtec, which will raise your compression

ditch hondata and go with a free program, crome etc.. you wont regret it
 
thank you for the help. any other comments/ suggestions? is there such thing as a compression calculator?
 
Stock B18B1 is 9.2:1. I was seriously contemplating doing a LS/VTEC and I learned a few things. I ended up changing my mind but this is what I know about the build. I think that B16 pistons (new and 0.5mm bigger for re-build) with your LS rods shot peen'd (or but aftermarket). That should clear with the right head gasket (I think B20 but don't quote me....buy the conversion kit and it comes with it) ARP bolts on rods and head. And new rod bearings that are in the tolerances (Honda OEM has many diff. size bearings). I think is a very important aspect of the build b/c spun bearing is the most common reason Frankenstein going snap, crackle, pop. Then Micropolish and balance the LS crank, run a different oil pump (type R) Lots of ECU chip options that have proven results for a LS/VTEC just find someone to tune it and buy what they like tuning with.
 
I'd have the whole bottom end balanced, which is why I suggested you have the machine shop assemble the bottom end in the first place.

It'd be best if they could balance the clutch and flywheel with the bottom end, especially if you have an aftermarket clutch and flywheel. The clutch tends to be the most out of weight on the whole bottom end assembly. Take the crank pulley as well. A good balance is always helpful with longevity and also creates a smoother running engine.
 
i have never heard of "balancing a clutch", but that is pretty interesting ill look into that. but i actually have just bought a b20b block that is fully built with low comp. (9 to 1) so i will start posting pics after i get it. the block is balanced along with a 84.50mm bore. it should be fun! both LS blocks i have are up for sale now and mint cond. PM me or page message if anyone wants one
 
has anyone tuned on crome?? sorry if i misspelled crome*.. my local tuner said they like to tune with that program and i have heard some great things about it but also some bad things
 
Its a good program from what I know and its all in the programing and tuning of the car (fuel ratios mostly)
 
^^ How do they go about balancing the clutch? Interesting
They will weigh it out and check for imperfections, I'm not exactly sure how it is done but they will also put a mark on the clutch and when you install it you need to tighten all the bolts with that side up (there will be a mark on your flywheel to match it up with). My guess is they probably put it on something and turn some revolutions and see if it's out of balance. My clutch disc has a couple holes drilled in the yellow part (dust shield, i guess?)
i have never heard of "balancing a clutch", but that is pretty interesting ill look into that. but i actually have just bought a b20b block that is fully built with low comp. (9 to 1) so i will start posting pics after i get it. the block is balanced along with a 84.50mm bore. it should be fun! both LS blocks i have are up for sale now and mint cond. PM me or page message if anyone wants one
nice, should be a good build
has anyone tuned on crome?? sorry if i misspelled crome*.. my local tuner said they like to tune with that program and i have heard some great things about it but also some bad things
my car is tuned on crome, made 320 at the wheels and its been running fine with no problems since
Its a good program from what I know and its all in the programing and tuning of the car (fuel ratios mostly)
exactly, CROME is a very well known program. almost all tuners that you run into will use it or are familiar with it.
 
CAFROG i want your EH3!!!!!

Thanks man. Its a labor of love lol. I'm trying to get it BAR'd in CA. I just need a P30 USDM ECU.

Once its BAR'd. I'm going to take the bottom end out (and keep it) So I can try to build a LS bottom that will last more then 25,000 miles (have yet to hear of that..) But what do you expect out of a bottom end that is asked to rev 2,000+rpm's higher then it was designed for.
 
Laskey is a good guy. He has helped me a few times. I would say his is pretty wise.

I could see balancing the clutch (to be in sync with the flywheel) althoguh it seems werird that they aren't balanced already.
The flywheel is something that is balanced on its own and I figure it wears out evenly (unless abused with a burnt out clutch)
 
Its not a good idea to balance the bottom end with a clutch and flywheel assembly. Here is a good article to read that dicusses this issue.

Laskey Racing Online Store

thats cool and all, but my ACT clutch was out of balance, as was the flywheel

i dont believe he balanced them actually on the end of the crank
ill have to ask him about his precise process. ive had no problems with my car and it does feel a lot smoother
 
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