alperx

Hi guys

I have an LS/VTEC with a stock B18c1 gsr head and my friend has got a Civic b16a2. Both are with wiseco low cr pistons with t3/t4 turbos with cast manifolds. There are no leaks in the exhaust systems.

The thing is, his b16a2 makes so little noise, while my ls/vtec makes so much noise coming from the engine. They both run well at around 14-15 psi.

What can be the noise sources on my ls/vtec ?
Any ideas ?

OneBadTurboCRV

Most likely you have a mechanical problem, isn't it obvious? There is essentially no differences other than oil squirters on the B16 that would change anything. Are you also sure the PTW clearances are exactly the same? There is nothing anybody will be able to tell you without a video of some sort. This is a pointless thread.

alperx

engine is revving 8000s with t3/t4 57 trim turbo for more than 10.000 miles.. what can be mechanical problems like ?
I just changed injectors, filter, manifold, etc. nothing inside.

how can I get a clue about the ptw clearances for both engines ? by measuring compression ? or anything else I may not know ?

I dont think videos really reflect the real sound, but this is a small video. the sound is the same from the beginning - since I did not had the chance of comparing with a b16a2 or any other vtec around since I live in a small village

Charlie Moua

iTrader: (3)

mechanical...

no engines are identical such as p2w.
ask the engine builder who put both blocks together.

if it's just "slapped" together... then you won't know what the specs are....


BTW are both 81mm pistons?

dc2lsvtech

Seems like it's just the ticking of a normal Vtec head you could adjust your valve lash to see if it quiets down or if you guys have different pistons flat top pistons seems to be quieter a lot of times..

alperx

ls/vtec has 81.5 mm
b16a2 has 81mm

both have the same sleeves built by the same builder.
I don't think we have the specs of those..

ls/vtec has a bit lower compression. (-12cc flat top)

la/vtec has these pistons : http://hondamarketplace.com/showthread.php?t=2664960

OneBadTurboCRV

Then what is this question even about? You have two differently built engines with different strokes at that. The answer has and will be mechanical differences. I have no clue why you would think all engines would sound alike. They all have their own "personality"...

alperx

well, when one of them is like sewing machine even at idle, I tried to find the reason but couldnt, so I just wanted to ask..sorry for that.

DirtyDA9

^^ then swap in a sewing machine. Might lose some ponies, but you will obtain the desired sound.

alperx

I guess u never knew how a sewing machine sounded. that's why u mix up the engines.

jimbo slice

If I had to guess I'd say two things: P-t-W clearance is probably too big and the valve lash is too loose. Don't forget... I'm just guessing

alperx

can valve lash be too loose in a stock gsr head ?

if I measure the compression in the cylinders, can a "guess" be made about the ptw clearance ?

OneBadTurboCRV

Of course valve lash can be too tight or too loose. You need to just take your car back to somebody who knows what they are doing. It is really that simple. Valve lash is of the basic necessity on these engines.

Also, there is no way you could possibly tell piston to wall clearance by a compression test. Take it to someone.

Muckman

iTrader: (2)

Does it sound better after it warms up?

alperx

well, a little bit. not very much it differs.

alperx

Thanks I'll try that valve lash thing.