Z350 heads on VQ30DE maxima ???
11-18-2009, 10:01 AM
#1
Member
Thread Starter
Join Date: Aug 2007
Posts: 293
Z350 heads on VQ30DE maxima ???
hi everyone
I'v got heads from a dead Z350 VQ35de engine . does it fit on VQ30DE maxima block 100% without any problems ?
I tried some invistegtions . I installed VQ30 internal intake that the pats comes with the injectors and feul rale . its fit 100% perfctly. and if we said that using 3.0 chain cover on 3.5 engine to make it fit on 4th Gen that mean 3.5 heads fits on 4th gen 3.0 block .
ok now I need suggestions and more investegations .
my goal is to use it for turbo .
thanx
11-18-2009, 11:35 AM
#2
hi everyone
I'v got heads from a dead Z350 VQ35de engine . does it fit on VQ30DE maxima block 100% without any problems ?
I tried some invistegtions . I installed VQ30 internal intake that the pats comes with the injectors and feul rale . its fit 100% perfctly. and if we said that using 3.0 chain cover on 3.5 engine to make it fit on 4th Gen that mean 3.5 heads fits on 4th gen 3.0 block .
ok now I need suggestions and more investegations .
my goal is to use it for turbo .
thanx
The 3.5 bore is larger - check valve and head clearances on 3.0 block.
Verify water passages will work w/3.5 heads on 3.0 block.
You will need 3.5 head gaskets to clear chambers.
Inner cover needs a couple of holes drilled out for 3.5 heads.
Valve covers need to be 3.5 - won't clear 3.0 UIM.
Coils need to be 3.5 to mount - won't clear 3.0 UIM.
3.5 heads have extra cam sensor holes - plug with sensors?
NOTE: some of these things may be wrong - others will advise.
Good luck...
11-18-2009, 05:43 PM
#3
one of the things i remember reading about putting 3.5 heads on a 3.0 block are that the compression will be raised. Also, due to the shape of the combustion chamber on the 3.5 heads, the likely hood of detonation due to those two issues is much higher. I don't think you'll want to use them since you want to use this for a turbo build. You would need a thicker head gasket (there's a cometic one for the 350z that may work) and reshape the combustion chamber. Free stuff is great, but I personally wouldn't take the risk on a turbo build using the 3.5 heads when the 3.0 heads flow well enough as is.
11-18-2009, 05:52 PM
#4
one of the things i remember reading about putting 3.5 heads on a 3.0 block are that the compression will be raised. Also, due to the shape of the combustion chamber on the 3.5 heads, the likely hood of detonation due to those two issues is much higher. I don't think you'll want to use them since you want to use this for a turbo build. You would need a thicker head gasket (there's a cometic one for the 350z that may work) and reshape the combustion chamber. Free stuff is great, but I personally wouldn't take the risk on a turbo build using the 3.5 heads when the 3.0 heads flow well enough as is.
11-19-2009, 03:13 PM
#6
Member
Thread Starter
Join Date: Aug 2007
Posts: 293
I have 3.0 cometic head gaskits . I combared the 3.5 headgaskit with my cometic and they are the same . but my cometic is thick . that means 3.0 gaskit works . and also I bought custome made pistons for 3.0 from CP so I dont think I have to reshape the combustion chamber .
about what grey99max said
to do the frist two issus I have to open 3.5 engine but as i said befor if the head gaskit are the same that mean the water passage is the same . am not 100% sure but this is by logic .
about coils and covers they will be 3.5 .
what about the air intake ? 3.0 intake holls has the eag shape but 3.5 is circle.
as I said befor 3.0 inner intake fits on the heads but the upper wont becouse of the hight of the head cover .
so if I want to use 3.5 air intake I have to buy new injectors right ? but are 3.5 injectors good for turbo up to 14 psi ?
about the sensors I have to plug them .
ok gusy . mooooore investegatios needed
about what grey99max said
to do the frist two issus I have to open 3.5 engine but as i said befor if the head gaskit are the same that mean the water passage is the same . am not 100% sure but this is by logic .
about coils and covers they will be 3.5 .
what about the air intake ? 3.0 intake holls has the eag shape but 3.5 is circle.
as I said befor 3.0 inner intake fits on the heads but the upper wont becouse of the hight of the head cover .
so if I want to use 3.5 air intake I have to buy new injectors right ? but are 3.5 injectors good for turbo up to 14 psi ?
about the sensors I have to plug them .
ok gusy . mooooore investegatios needed
11-20-2009, 07:13 AM
#7
I have 3.0 cometic head gaskits . I combared the 3.5 headgaskit with my cometic and they are the same . but my cometic is thick . that means 3.0 gaskit works . and also I bought custome made pistons for 3.0 from CP so I dont think I have to reshape the combustion chamber .
about what grey99max said
to do the frist two issus I have to open 3.5 engine but as i said befor if the head gaskit are the same that mean the water passage is the same . am not 100% sure but this is by logic .
about coils and covers they will be 3.5 .
what about the air intake ? 3.0 intake holls has the eag shape but 3.5 is circle.
as I said befor 3.0 inner intake fits on the heads but the upper wont becouse of the hight of the head cover .
so if I want to use 3.5 air intake I have to buy new injectors right ? but are 3.5 injectors good for turbo up to 14 psi ?
about the sensors I have to plug them .
ok gusy . mooooore investegatios needed
about what grey99max said
to do the frist two issus I have to open 3.5 engine but as i said befor if the head gaskit are the same that mean the water passage is the same . am not 100% sure but this is by logic .
about coils and covers they will be 3.5 .
what about the air intake ? 3.0 intake holls has the eag shape but 3.5 is circle.
as I said befor 3.0 inner intake fits on the heads but the upper wont becouse of the hight of the head cover .
so if I want to use 3.5 air intake I have to buy new injectors right ? but are 3.5 injectors good for turbo up to 14 psi ?
about the sensors I have to plug them .
ok gusy . mooooore investegatios needed
Using the 3.5 heads will drop the CR slightly. The FSMs for both engines show the combustion chamber volumes, I think.
The 3.5 intake head ports are a lot different from the 3.0 manifold ports - lots of turbulence, even if you can make that work.
The head gaskets should have the larger 3.5 cylinder bore size - otherwise the edge of the gaskets will be sitting out in the combustion chamber and glowing in the dark = detonation. Cometic gaskets may work - dunno.
The water openings in the 3.0 block must match up to the 3.5 heads and gaskets openings.
If the water ports line up OK, you can use the 3.5 heads, LIM and UIM manifolds, fuel rails and injectors. This way, all the ports match. There will be lots of injector choices. This would be a good time for cams.
11-20-2009, 10:45 AM
#9
BTW this is probably the worst hybrid idea of the bunch.
11-20-2009, 02:39 PM
#11
I only say that because of the combustion chamber inefficiencies that might be created. No one knows for sure how well they will work together so you might shut all of us doubters up eventually. Either way, good luck.
Thread
Thread Starter
Forum
Replies
Last Post
MikesChevelle
5th Generation Maxima (2000-2003)
4
08-06-2015 11:36 AM