The definitive gsr engine build article

[boosted hybrid]

I just did an engine assembly last week with the 3/8" arp's, I remember the torque spec was 48 ft/lbs, i believe the stretch was in the mid 0.0050"s....if I run across the sheet I'll post up the spec.

[m1ch431_g]

3/8" ARP 2000
43 ft. lbs. TORQUE
.0055" - .0059" ROD STRETCH

got it off the sheet supplied.

so I could use my teeth to tighten the rod bolts & as long as the stretch bolt gauge measures to within specs it will be fine right?

been followin' this thread to help me build my 1st motor
picked up a bolt stretch gauge
and wasnt sure on whether I should shell out a lot of cash for a torque wrench.

[hotaccord243]

hey boosted hybrid,
i saw a book you were pointing at when i was reading this i was wondering what book you were using? great right up by the way it was wonderful,
devin

[boosted hybrid]

It was a Haynes manual. Get a Helms! Haynes sucks in comparision.

[prayr]

what are the dangers in re-using main/rod bearings?

also what hp level do you think the SRP pistions are rated for....

plan is turbo ls...my goal and belief is i will reach over 300hp....

i plan on installing internals while the block is still in the car...and not removing the crank because i just don't have everything it would take to do so...if i take precautions can i hone cylinders with drill/hone?...

[Lans~]

great info. I'm actually using this as a guide in my 1st engine building.

But excuse my ignorance, regarding the piston to wall clearance. Isn't 3.209" the bore diameter needed to get a clearance o 0.003? So if you're aiming for 0.0031 shouldn't it be 3.2091 instead of 3.2121?

I'm sorry if I'm mistaken, but that's how it looks like on my cp pistons spec sheet.

[Whitey]

I was reading through this and I noticed you said nothing about getting the rotating assembly balanced. I thought it was a necessity to get everything balanced if your putting in rods and pistons.

[boosted hybrid]

great info. I'm actually using this as a guide in my 1st engine building.

But excuse my ignorance, regarding the piston to wall clearance. Isn't 3.209" the bore diameter needed to get a clearance o 0.003? So if you're aiming for 0.0031 shouldn't it be 3.2091 instead of 3.2121?

I'm sorry if I'm mistaken, but that's how it looks like on my cp pistons spec sheet.

You are correct, the piston to wall clearance is built into the bore diameter, so you would shoot for 3.209. What i had measured in the picture was correct, for some reason i had posted that.

I was reading through this and I noticed you said nothing about getting the rotating assembly balanced. I thought it was a necessity to get everything balanced if your putting in rods and pistons.

I dont balance the rotating assembly when building turbo engines. The pistons are within a gram of each other, as well as higher quality rods. The cranks are balanced very well from honda. The only thing that would need to be balanced is the flywheel/clutch assembly.

[Whitey]

I dont balance the rotating assembly when building turbo engines. The pistons are within a gram of each other, as well as higher quality rods. The cranks are balanced very well from honda. The only thing that would need to be balanced is the flywheel/clutch assembly.

What about Eagle rods and JE pistons?

[boosted hybrid]

Look at the eagle spec sheet for the rod weight tolerance. I think its 2-3 grams.

[Corey]

Very good Article. i have looked over this thread a few times.

I just wanted to add when using micrometers, dial bore gauges and measuring clearances on the crank and block to make sure the temps are all the same. When using the Micrometers, touch only the plastic part, Don't touch the crank when taking measurments, etc

I've seen measurments change as much as five tens of a thousands by measuring in different temps.

Don't quote me on this but I think 68 degrees is a standard temp for taking measurments.

[Speedracer228]

Great write-up! I had to read it a few times to mostly understand everything. Ive always wondered what went into building up a shortblock like this the RIGHT way, and this pretty much answered everything I had questions about. :thumbup:

[project dc2]

i had a question

i built my motor using this article.


used ACL bearings. GE sleeves. eagle 3/8 rods, CP pistons. .017 top ring gap .015 middle ring gap i believe.

i plastigauged everything and it all checked out.

when i installed the piston i had to twist the rod a little and it ended up my end gaps being on the thrust points making my leakdown test turn out like shit.

my dad pulled the head off and redid the piston for me while i was at school and put it back in. and said he went 5 lb over stock specs cuz he didnt know what torque specs the eagle rods were supposed to be at ( fucker didnt ask me)


SO anwyays

im sure you've read i made 400 WHP and 355 torque on the GT2871R

i felt a major loss in power after a few days on a pull on the freeway.,

oil good, oil pressure good, no water oil mix. boost good, connectors good.

anwaysy after testing and what not i spun a bearing


what causes spun bearings? to loose of a clerance or too tight?


so how do i measure what thicknesses etcc i need to go with now? and i can reuse the ACL bearings on cyl 1 2 and 4 right ?


more detailed description on how the whole ordeal went through

http://honda-tech.com/zerothread?id=1046098&page=16


thanks

[Johnmay19]

Too tight will cause a spun bearing(oil starvation of the bearing). Just measure the old bearing use plasti-gauge then figure what bearing size you need for the reccomended clearance. Do not reuse the bearings. Plasti-gauge all the bearings to prevent another spun bearing. This time go with all honda bearings. Good luck.

[boosted hybrid]

The bearing spun due to lack of oil clearance, most likely due to the over tightening of the rod bolts.

The gap on the rings sounds a little to tight. I always use the following to figure out ring gap:

Cylinder Bore*0.006"=Top ring gap.

Add another 0.004" to the top ring gap to get the secondary ring gap.

Ring placement is critical to ring seal. Its hard to get the rings 100% right when you are using a ring compressor installing them, but its something that takes practice and experience in getting right.

Def. dont reuse the bearings. I would have the crank and rods inspect on the journal surfaces if you spun a bearing. Make sure you measure the journal bore on the rods to see if they are still true after spinning a bearing.