wondering what a rough est. of a compression ration would be on a ld9 with 456 head
roughly 11.37 but that was calculated using 99plus pistons, it would be slightly less for the older LD9s. You can get away with this on premium pump gas and HPtuners to adjust for knock. I ran like this for quite a while with my 086 head.
What head is the 456 head?
IIRC, it's the next best thing you can get to the 086 head.
i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
The 456 head is the late 94/95 2.3 head. The ones from 95 accept the 2.4 water neck. In stock form they outflow the 086 until lift passes .350. Its is also said they can be ported to flow as much as a ported 086.
When you say 2.3 you mean which one? LO?
The only head for those years...the 086 was the LO/HO head for I believe 89.5-92, 753 was GM's replacement for the cracking 086 and is also a good head.
its going in my 95 z untill my h.o motor is done im gonna run 99 2.4 with 456 head secret cams walbro 255 and little bigger injectors fow now any one around the PA area with hp tuners gonna need get knock taking care of also a question anyone try run the 2.3 crank in a 2.4
That would de-stroke the engine to a 2.2 and you would need bearing spacers because the 2.3 crank is smaller than the 2.4 mains.
how did your car run on that setup? i am running 99 pistion
I had a 01 bottom end and stock 2.4 cams, custom header, full exhaust, and HO intake with 57mm throttle body. It ran great. The only reason I took the head off was because I will be using it on another more powerful 2.4.
Its what was in my car already...plus I didnt mind the extra compression.
ANY IDEA WHAT A ESTIMATE HP RATING WOULD BE
just an FYI the 456 head is basically the worst over all head for the 2.3L Quads. They say a 456 to an 086 head swap does wonders on the 94 &95 quads. So on a twin cam you should get the same gain from 456 to 086.
jake sheeran wrote:just an FYI the 456 head is basically the worst over all head for the 2.3L Quads. They say a 456 to an 086 head swap does wonders on the 94 &95 quads. So on a twin cam you should get the same gain from 456 to 086.
Wrong, ported it flows damned near the same numbers as the 086. Also stock for stock the 456 outflows the 086 up until .350 lift, the 2.4 cams have .354 lift.
i did reasearch the 456 head which is ported and having the secret cam swap put in
with the 456 head are the head gasket the same as 2.4?
I ran a felpro 2.4 head gasket just matched the head to the gasket there are pics on here somewhere showing what to match and what not to. search 086 swap.
