You could pick up a 6.0 short block for cheap. Everything you have will swap over. Your 5.3 heads would work well on a 6.0 giving it a nice bump in compression over 317's.
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317 heads are 71 cc's your 862's are 61 cc's. I think thats a bit much! lq4's have 9.4:1 compression. I think that would bump it over 11:1Originally posted by sman View PostKinda my thoughts.
Anyone know the info to calculate the CR of an lq4 with 862's?
The problem being is that, the 862 heads have smaller intake valves. You would pick up compression but, lose flow. Not good.
862
Combustion Chamber Volume: 61.15cc
Compression Ratio: 9.5:1
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 1.89 inches
Exhaust Valve Diameter: 1.55 inches
Stock Head Flow Numbers
Chamber 61.15 cc----0.100--0.200--0.300-- 0.400--0.500---0.550---0.600
Intake 200 cc----------63 ---128----179-----210----218----221-----226
Exhaust 70 cc----------54 -- 93 ----121----145-----163----168----174
317s
Combustion Chamber Volume: 71.06cc
Compression Ratio: 10:1 LQ9 Flat top pistons
Compression Ratio: 9.6:1 LQ4 Dish piston
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches
Stock Head Flow Numbers
Chamber 71.06cc----0.100---0.200--0.300--0.400--0.500--0.550--0.600
Intake 210cc-----------66-----142-----196---228----236---238-----240
Exhaust 75cc----------59-----104-----137---155----167---173-----177Last edited by shawnc16; February 13th, 2011, 04:44 PM.-08 G8 GT DD: Rotofab CAI, HID's, Breyton Race GTS'
-86 Iroc Project: LQ4, Th400, S400, Ford 9"
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Good, im not crazy, lol. I punched some numbers in a online CR calulator and got like 11.14 or somthing, I was like, huh, I must have messed up. I guess not, haha.
Honestly thoughts were cam in the mid 230 range, move the rest of the parts over from the 5.3(minus heads as I now see) and drive it. This will be like the 3rd year in a row the motors been out of the car.1999 Camaro - 6 liters of fury.....

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Join the club! Theres a guy on here selling an lq4 complete! Pick it up! $750 complete is a pretty solid deal.Originally posted by sman View PostGood, im not crazy, lol. I punched some numbers in a online CR calulator and got like 11.14 or somthing, I was like, huh, I must have messed up. I guess not, haha.
Honestly thoughts were cam in the mid 230 range, move the rest of the parts over from the 5.3(minus heads as I now see) and drive it. This will be like the 3rd year in a row the motors been out of the car.
EDIT:
Looks like yur on top of it!Last edited by shawnc16; February 13th, 2011, 04:57 PM.-08 G8 GT DD: Rotofab CAI, HID's, Breyton Race GTS'
-86 Iroc Project: LQ4, Th400, S400, Ford 9"
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Ive got my eye on that one and one that my dads friend has, that im going to look at tomorrow night. It was supposedly new, but after some talking to the actual owner, its not new. But supposedly ridiculously clean, dont know if its a 4 or a 9 tho, and the mileage is unknown, just like my 5.3 that lasted me 2 years........
Is there any way to tell the difference between a 4 and 9 without pulling a head or peaking in a spark plug hole?1999 Camaro - 6 liters of fury.....

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As far as I know there is no actual way to tell other than looking at the piston. The ONLY difference between the two are the pistons (which is what changes the compression ratio) Unless the guy knows what the engine came out of. Chances are its an lq4-08 G8 GT DD: Rotofab CAI, HID's, Breyton Race GTS'
-86 Iroc Project: LQ4, Th400, S400, Ford 9"
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Thats basically what I was getting at. The LQ9s are pretty rare still, when ya do find em, people want stupid amounts of money for em. Good luck with it. Hopefully you get back out on the road pretty soon! My swap probably wont be done!Originally posted by sman View PostYea, im counting on it being an lq4, just because of the sheer difference in production numbers, odds are, its a 4.-08 G8 GT DD: Rotofab CAI, HID's, Breyton Race GTS'
-86 Iroc Project: LQ4, Th400, S400, Ford 9"
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LOL! Nope Im not waiting on coils. Im waiting on money haha. Im doing the LQ4 swap with a turbo as well. Trying to get my engine together as much as I can before I drop it in but, I want all the parts available so I'm not waiting around for something to show up. I actually just picked up a set of coils recently so, you dont have to tear up the garage anymore! The only thing I need now is aftermarket stuff.Originally posted by sman View PostWhat are you waiting on!
Dont tell me coils... I tore the place apart yesterday after I did the leakdown test looking for them for you, no dice. Someone must have thrown them out, pisses me off, I swear I wish I had the only key to that place....-08 G8 GT DD: Rotofab CAI, HID's, Breyton Race GTS'
-86 Iroc Project: LQ4, Th400, S400, Ford 9"
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Even a set of 243's will bump the compression and flow well. They can be had cheap. I saw a few sets go on here for around $350.
Heck even bumping the compression into the 11's with the 862's might still make more power than 317's with a better flow number but more than a full point less in static compression. You would have to talk to someone who builds engines to figure that out tho.
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I'm looking at a list of about 10 all under $1000. For only $1K though, they will have higher miles.Originally posted by sman View PostOh, id love to put a lq9 in it. Just having trouble finding one. If I could get one in the 1000 dollar range id do it no problem.
Not sure if I'm allowed to post it on here though.Last edited by TrickyTransAm; February 17th, 2011, 08:52 PM.
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