ld9 086 head swap - Performance Forum

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ld9 086 head swap
Tuesday, November 10, 2009 3:20 PM
I race a 97 ld9 car. ( circle track) Have secret cam swap done and have been doing well. Have been reading about the 086 head swap. I have to stay naturally aspirated. Would like to bump up compression and add the eagle rods. What do you suggest swap to 086 head or not? If so what cams to use and also what pistons to keep clearances. Also how about head gasket? Thanks in advance.

Re: ld9 086 head swap
Tuesday, November 10, 2009 5:55 PM
086 head, 9:1 CR LD9 pistons(rated with stock head), slightly thicker head gasket, HO or W41 cams.....that would be nice.


"Never argue with an idiot. They'll drag you down to their level, then beat you with experience!" -Anonymous
Re: ld9 086 head swap
Tuesday, November 10, 2009 5:58 PM
Make sure you have valve pockets for the HO cams for clearance...





Re: ld9 086 head swap
Tuesday, November 10, 2009 6:45 PM
Valve pockets?










~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
Re: ld9 086 head swap
Tuesday, November 10, 2009 6:47 PM
swap heads and see what you run. i believe the biggest cams you can run with the 086 is the secret cams with stock pistons.



Re: ld9 086 head swap
Tuesday, November 10, 2009 7:03 PM
if you wanted bigger cams than secret cams what pistons and cams would you recommend
Re: ld9 086 head swap
Tuesday, November 10, 2009 8:35 PM
HO cams with the wiesco 9-1 pistons, youll need custom valve pockets cut in as said above. you will end up with somewhere around 10.5-1 compression.



Re: ld9 086 head swap
Tuesday, November 10, 2009 9:05 PM
bore block .080 over and do 2.3 oil pump conversion with custom oil pump pickup relocation aluminum block to relocate oil pickup to fit inside stock pan so officials do not know.

wiseco domed pistons with valve reliefs, .080 over. and eagle or crower rods.

086 head with machined combustion chambers, sivalves.com ss valves and bronze/magenese valve guides.

cometic head gasket with custom larger fire ring positions to compensate for .080 over bore.

gutted and re-balanced, cross drilled and re-chamfered crankshaft with center main cap strengthening braces.

HO or W41 cams, intake cam modded with hex drive for use with 2.4 power steering. use 2.3 exhaust cam tower, have 2.4 intake cam tower lifter bores opened to 35mm. sealed power lightweight 35mm lifters.

ho 2.3 crank pulley, md ld9 aluminum alt pulley powdercoated black to look stock. GM ac delete pulley. GM egr delete plate.

ho intake manifold and smg or OEM polished/powdercoated and bored 60mm throttle body.

ho exhaust manifold port matched and collector ported. 3" mandrel bent downpipe.

ford brown top injectors and use hp tuners with a custom dyno tune.

enjoy lapping everything out there









Edited 1 time(s). Last edited Tuesday, November 10, 2009 9:07 PM


I must confess... I feel like a monster!
Re: ld9 086 head swap
Wednesday, November 11, 2009 3:04 AM
What if I wanted to swap an 086 head onto a stock 2.4? Slightly thicker headgasket and its possible on a stock bottom end?



Re: ld9 086 head swap
Wednesday, November 11, 2009 4:10 AM
gtpsunfire wrote:What if I wanted to swap an 086 head onto a stock 2.4? Slightly thicker headgasket and its possible on a stock bottom end?

depends on cams.



PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
Re: ld9 086 head swap
Wednesday, November 11, 2009 4:48 AM
jmarks82 wrote:Make sure you have valve pockets for the HO cams for clearance...


You will be fine without valve relief's with .410 lift cams and .074 headgasket, and more lift or thinner HG then you will need them

WHITECAVY wrote:Valve pockets?


my LG0 11:1 pistons with valve reliefs








Jason
99 Z24 Supercharged
157hp/171tq - NA
190hp/170tq @ 6psi

LG0/LD9 for Life

Re: ld9 086 head swap
Wednesday, November 11, 2009 5:08 AM
With the 086 head, LD9 block and bottom end, AND HO cams you will need valve reliefs. You could run LO cams and should be fine. But notice LO pistons dont have valve pockets and HO pistons do. Idk maybe the thicker head gasket would help...





Re: ld9 086 head swap
Wednesday, November 11, 2009 5:23 AM
jmarks82 wrote:With the 086 head, LD9 block and bottom end, AND HO cams you will need valve reliefs. You could run LO cams and should be fine. But notice LO pistons dont have valve pockets and HO pistons do. Idk maybe the thicker head gasket would help...


I would agree with the first part if a stock headgasket were being used.




Jason
99 Z24 Supercharged
157hp/171tq - NA
190hp/170tq @ 6psi

LG0/LD9 for Life
Re: ld9 086 head swap
Wednesday, November 11, 2009 5:32 AM
raf (dohc tuner) did an 086 head with ho cams on wiseco dished pistons with custom valve reliefs.

far as i know the car runs and runs well...



I must confess... I feel like a monster!
Re: ld9 086 head swap
Wednesday, November 11, 2009 5:51 AM
Valve RELIEFS ok hehe, thats what I know them of, thanks J.











~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
Re: ld9 086 head swap
Wednesday, November 11, 2009 2:00 PM
If I use a wiesco pistons 9:1 and a HO cams with thicker head gasket would I be alright or rather us stock gasket with valve reliefs?
Re: ld9 086 head swap
Wednesday, November 11, 2009 5:24 PM
Stock LG0 Pistions have Valve cuts...

So do my Flat tops (once more, LG0\W41 Enigine)

So yes, you would need them with this head on a LD9

Chris




'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

Re: ld9 086 head swap
Wednesday, November 11, 2009 6:37 PM
Are there certain pistons i can buy with valve cuts in them or need machine work? Also what intake would be good HO Or LO or something else?
Re: ld9 086 head swap
Thursday, November 12, 2009 2:39 PM
CUSTOM.

Chris




'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

Re: ld9 086 head swap
Tuesday, March 08, 2011 8:03 AM
ok so if you just put a 2.3 head on a ld9 with secret cams you wouldnt need a thicker gasket or differetnt pistons or valve reliefs?
Re: ld9 086 head swap
Tuesday, March 08, 2011 8:37 AM
You would be fine, it has been done lots of times.




Re: ld9 086 head swap
Tuesday, March 08, 2011 8:53 AM
see the thing with the piston to valve clearance is its tricky... you cant just think of it in terms of thousandths of an inch. you also need to factor in valve timing events and stroke.

i firmly believe its over thought and we worry about it just a little bit too much around here. from what i have read its a good idea to have around .080 piston to valve clearance (for ur specific valve timing event and stroke). in my findings our engines have well over .100, which is plenty.

you would think the LD9 has more clearance due to the smaller cams and different position of the valves in the combustion chamber... but thats wrong. the LD9 actually ends up with less piston to valve clearance than a quad 4 due to the longer stroke. the quad 4 has LOADS of clearance due to its smaller stroke. from what ive read and heard... up wards of around .200 in a stock configuration.

take my LD9 im building for example, wiseco non valve relief cut dished pistons (aka the 9:1's), decked block .005 and with a piston rock of .002, adds up to a total of .007. with a stock thickness head gasket (around .050), and .020 cut off the deck of the head using HO cams i had .130 of clearance.

is it a good idea to measure everything urself on ur engine? yes, 100% absolutely. confirm what you have, it never hurt anyone. valve reliefs are a good idea for peace of mind and added security say ur float a valve, etc...



If it takes forever.... I will die trying. Underdog Racing
Re: ld9 086 head swap
Tuesday, March 08, 2011 9:23 AM
People have run the secret cams in this setup several times. A guy or 2 says they have run HO cams in this setup with stock pistons but offer no proof but word of mouth and no running engine to proove it. I agree with what brad said above. However the 086 valves are bigger and sit physically closer to the piston. So I would imagine it has less than .130 clearance. However with a .074 thick head gasket assuming a stocker is .045 (I think it is but am not sure) that's gives .029 extra room for lift. So sectret cam intake lift is .365 plus .029 is .394 that you know your safe at that lift. I would be willing to bet there is enough room for the .410 lift of ho cams. Compression would still be pretty high I'm sure.



Re: ld9 086 head swap
Tuesday, March 08, 2011 9:09 PM
There is no issue with a HO exhaust cam. I've done it, but had a bad 2.3L cam tower with too much clearance between the timing cover, so it constantly leaked oil. I've never tried the HO intake. Just an fyi, 2.3L HO pistons come factory with reliefs only on the intake side, which should give a good indication that the intake has less clearance on a symmetric piston face (i.e. one with no reliefs).




I have no signiture
Re: ld9 086 head swap
Tuesday, March 08, 2011 9:39 PM
the w41 pistons come with 4 valve reliefs...

and brian, the reason it leaked oil between the tower and the housing, you sure it wasnt the little soft plug in the end that was leaking?

Whalesac wrote: Just an fyi, 2.3L HO pistons come factory with reliefs only on the intake side, which should give a good indication that the intake has less clearance on a symmetric piston face (i.e. one with no reliefs).


LOL or it could mean GM was just trying to play it safe.



Edited 1 time(s). Last edited Tuesday, March 08, 2011 9:40 PM


If it takes forever.... I will die trying. Underdog Racing
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