My LS1 just spun a bearing so i figured i would build an LQ4 to make better numbers. My question is since the LQ4 is gonna get new rings and bearings since its already gonna be in short block form what else do i need to do to to the internals to make 11.1 compression. Use flat top pistons? I know the heads can be milled to bump up the compression but im not sure if i want to mill a set of heads to have my cam options pretty limited after that. My car needs to pass smog since im in CA anyways so i will probably put in a TR224 but who knows. So if you guys can help me out with the compression question that would be great.
__________________ 99 Trans Am, TSP 1 7/8 Long Tube Headers, TSP X Pipe w/ Bullet Mufflers, LS1 Motorsports Lid, SLP Mass Air, Textrallia OZ700, Synergy Motorsports Built T-56
Blew up motor, oh well time to build the LQ4 so everyone will only see my
Def gonna need flat tops. Whatever compression depends on piston choice and combustion chamber size. Smaller combustion chambers for a given piston will yield higher compression. You need to find a piston to match whatever heads you decide to go with. I would suggest 243 castings vs the 317's because it's the same exact head but the 317's have a larger 72cc combustion chamber while the 243's have 64cc (I think).
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Bought from: 02blutb
Sold to: matthimself456
i was probably gonna run the PRC stg 2.5 ls6 heads. or the PRC 215 heads that texas speed sells since they are in my price range. does anyone know what a good set of pistons would be? and is it worth buyin forged ones? i want to run a 100 or 150 wet shot on the car but it was to my understanding that the lq4 internals are pretty strong? my goal is to have a low 12 second 1/4 mile car on street tires(12.1 or 12.2's) but have a car that hauls ass on the freeway
__________________ 99 Trans Am, TSP 1 7/8 Long Tube Headers, TSP X Pipe w/ Bullet Mufflers, LS1 Motorsports Lid, SLP Mass Air, Textrallia OZ700, Synergy Motorsports Built T-56
Blew up motor, oh well time to build the LQ4 so everyone will only see my
who makes or sells a good set of forged flat tops? are the rods strong enough to last? i mean a set of eagle h beams are no too much so maybe i should get some. but if the stockers are fine than ill stay with those.
__________________ 99 Trans Am, TSP 1 7/8 Long Tube Headers, TSP X Pipe w/ Bullet Mufflers, LS1 Motorsports Lid, SLP Mass Air, Textrallia OZ700, Synergy Motorsports Built T-56
Blew up motor, oh well time to build the LQ4 so everyone will only see my
who makes or sells a good set of forged flat tops? are the rods strong enough to last? i mean a set of eagle h beams are no too much so maybe i should get some. but if the stockers are fine than ill stay with those.
stockers are pressed fit pins, so will have to use replacement pistons on stock rods, other than that will need aftermarket rods and pistons.
mite as well go with forged rods,pistons on stock crank
stockers are pressed fit pins, so will have to use replacement pistons on stock rods, other than that will need aftermarket rods and pistons.
mite as well go with forged rods,pistons on stock crank
could the stock crank handle lets say a 200 shot?
__________________ 99 Trans Am, TSP 1 7/8 Long Tube Headers, TSP X Pipe w/ Bullet Mufflers, LS1 Motorsports Lid, SLP Mass Air, Textrallia OZ700, Synergy Motorsports Built T-56
Blew up motor, oh well time to build the LQ4 so everyone will only see my
If your just gonna do a 224 cam, look at my setup... I'm right at 11.2:1 compression with an LQ4 and a 224R cam... My heads are milled to 59cc with the stock dished pistons. Runs great!
.060 =375ci with stock crank
4.06 bore x 3.622 stroke = 375ci
thru stock ls6 intake/bbk 85mm tb
was there anything that needed to be done to the stock crank and stock rods to have them work with the 375? sorry for all the questions. im just tryin to weigh out all my options
__________________ 99 Trans Am, TSP 1 7/8 Long Tube Headers, TSP X Pipe w/ Bullet Mufflers, LS1 Motorsports Lid, SLP Mass Air, Textrallia OZ700, Synergy Motorsports Built T-56
Blew up motor, oh well time to build the LQ4 so everyone will only see my
was there anything that needed to be done to the stock crank and stock rods to have them work with the 375? sorry for all the questions. im just tryin to weigh out all my options
nope, the pistons are made to be pressed to stock rods, engine was align honed for proper spec, rods were honed with arp bolts, tq plate honed,decked .006. just basic machine work.
speed pro pistons pressed to stock rods, 1/5/1.5/3.0mm rings. i assembled the engine. using clevite bearings, cam bearings were installed by machine shop. and i assembled the rest, degreed cam etc.
pistons and rings are less than 400$
Def gonna need flat tops. Whatever compression depends on piston choice and combustion chamber size. Smaller combustion chambers for a given piston will yield higher compression. You need to find a piston to match whatever heads you decide to go with. I would suggest 243 castings vs the 317's because it's the same exact head but the 317's have a larger 72cc combustion chamber while the 243's have 64cc (I think).
i would not do that, it is best to have a bigger combustion chamber, because fuel will be less prone to preigniting compare to a same motor with the same CR but smaller cc heads. so i would keep the 317 heads and raise the cr with a piston. the 317 heads flow pretty well too.
nope, the pistons are made to be pressed to stock rods, engine was align honed for proper spec, rods were honed with arp bolts, tq plate honed,decked .006. just basic machine work.
speed pro pistons pressed to stock rods, 1/5/1.5/3.0mm rings. i assembled the engine. using clevite bearings, cam bearings were installed by machine shop. and i assembled the rest, degreed cam etc.
pistons and rings are less than 400$
thanks for the info NemeSS. one more thing. whats the cr on your motor? and do you dd your car?
__________________ 99 Trans Am, TSP 1 7/8 Long Tube Headers, TSP X Pipe w/ Bullet Mufflers, LS1 Motorsports Lid, SLP Mass Air, Textrallia OZ700, Synergy Motorsports Built T-56
Blew up motor, oh well time to build the LQ4 so everyone will only see my
How to get 11.1 compression in a LQ4 
