Hey hows it going i just bought a 2.4 LD9 short block and im getting a cylinder head soon but i was wondering where do i need to start when i start building this motor. I plan on making it a performance motor so i was curious should i start with rebuilding the cylinder head (cam, lifters, port polish, and ect) or should i start with the block (.30 punch, forged pistons, rods, ect) what are some pointers i should know about shaving the head and other things. sorry im new to this tuning thing any info at this time would be much appreciated!
start whereever you want either way your going to have to do it all but what I did was start with deciding the head and cams, the I went for pistons, but I am hoping you know what your doing as asking a question like that is doubting it. anyways read read and read some more all the answers can be found...I have posts, Zyaaa has posts, Paul T has posts, but those are mainly n/a, reading is your friend
"As I lay rubber down the street, I pray for traction I can keep, but if I spin and begin to slide, please dear God protect my ride." -Amen
Oh i know what im doing its just that i thought there was a specific sequence to where i need to start i just recently dropped a 2.4 (regular) in my z24 i love it and im sure these LD9s have a lot of potential im not trying to build this thing quick i just wanna do it over time. I went to pick n save yesterday and found me a 2.3 exhaust cam (out of a 90 grand am) got it for 20 bucks so why not right lol but what im doing is gathering the parts then once i have everything i need imma send it to a motor specialist to put it together and i can put in the motor myself
I would say if you bought a short block take your time and do it right. What are your goals for the engine? Daily driver, street/strip, full race? all that dictates where to start and how much you want to dive into. Are forged rods and pistons stronger? yes, which means more abuse can be taken. In our engines are they lighter? Yes, which means less power made will be lost because the engine doesnt have to work so hard to turn. Are they necessary for a peppy daily driver? no. I do recommend the 2.3 oil pump swap no matter what. you'll need to take into consideration what compression you want. Are you staying N/A or planning on boosting eventually? do you want to get away with low grade pump gas or be limited to premium? Is the head and /or block surfaces straight? This will determine if the head or block should be shaved/decked/milled whatever you may call it, unless you wish to do so purely to raise compression.
The head, cams, and valvetrain are also an important part of an engine build. But again your total goal for the engine and budget are factors here. If your going through all of this keeping the stock cams is silly in my opinion. Will you be sticking to the mild secret cams(cheap easy drop in but wont make a ton of power), a bit more aggressive HO or W41 cams(will need cam tower mods, power steering hex installed in cam, 35mm lifters, better valve springs), or something a bit more such as old crane cams or one off custom grinds(also need same stuff as HO cams)
Port and polish, valves, springs will all also be determined depending on goals for the engine.
my goal with this car i would say is street/strip i mean i wont be driving it everyday thats what my other cavy is for but i plan on also boosting this motor
I would then probably start with the bottom end then. Since it isn't a daily driver I vote high compression 10.5-11ish range(premium gas required). Get your head and block checked to see if they need decking before buying a head gasket or pistons. I would probably look up a compression calculator on google, it'll ask you for all kinds of details that you can use in deciding what combination of parts to use. Forged rods and pistons probably would be good. Probably stick to HO cams/springs and 2.3 35mm lifters. Have a 2.4 cam tower bored to the 35mm lifters and hex added to the HO cam. For head a good but not crazy port and polish and SS valves will probably work well.
I guess id stay with ld9 valves. You can go with 1mm over sized valves. They are lighter than the2.3 valves. Also if you get a good angle grind on them they will breath a lot. Get your towers bored out for 35mm lifters and us 2.3 springs and find some ti retainers, get some ho cams from northern auto parts. Send them in and have them reground to yyour specs. Or find some hg2 cams. Have your crank lightend and balanced, have your head ported and polished or send it to me ill do that for you. Then have it taken to a machine shop to have it decked and. Cleaned. Gett some of the adjustable cam gears a rons header. Choose your pistons size and desirable cr. Clevit bearings, coatings if you want them. Youcan get hptuners. . You should have a reasonably strong motor.
Zs Z wrote:I would then probably start with the bottom end then. Since it isn't a daily driver I vote high compression 10.5-11ish range(premium gas required). Get your head and block checked to see if they need decking before buying a head gasket or pistons. I would probably look up a compression calculator on google, it'll ask you for all kinds of details that you can use in deciding what combination of parts to use. Forged rods and pistons probably would be good. Probably stick to HO cams/springs and 2.3 35mm lifters. Have a 2.4 cam tower bored to the 35mm lifters and hex added to the HO cam. For head a good but not crazy port and polish and SS valves will probably work well.
10.511 on a turbo thats going to be a pain to tune, the rest I basically agree with, but I never went for oversized valves with my build. stayed stock as I am N/A, oversized would be great for the turbo though. Biggest thing is don't cheap out or you will regret it, oiling system was not mentioned, upgrade to the 2.3 oiling system (your bearings will thank you). I would say go about 9-10 max compression for the turbo build, there are a few guys here with monster turbo builds that you can ask about, going n/a there are alot of us that can lead you places. boost cheaper (to extent), n/a more respectable
"As I lay rubber down the street, I pray for traction I can keep, but if I spin and begin to slide, please dear God protect my ride." -Amen
AJ B wrote:Zs Z wrote:I would then probably start with the bottom end then. Since it isn't a daily driver I vote high compression 10.5-11ish range(premium gas required). Get your head and block checked to see if they need decking before buying a head gasket or pistons. I would probably look up a compression calculator on google, it'll ask you for all kinds of details that you can use in deciding what combination of parts to use. Forged rods and pistons probably would be good. Probably stick to HO cams/springs and 2.3 35mm lifters. Have a 2.4 cam tower bored to the 35mm lifters and hex added to the HO cam. For head a good but not crazy port and polish and SS valves will probably work well.
10.511 on a turbo thats going to be a pain to tune, the rest I basically agree with, but I never went for oversized valves with my build. stayed stock as I am N/A, oversized would be great for the turbo though. Biggest thing is don't cheap out or you will regret it, oiling system was not mentioned, upgrade to the 2.3 oiling system (your bearings will thank you). I would say go about 9-10 max compression for the turbo build, there are a few guys here with monster turbo builds that you can ask about, going n/a there are alot of us that can lead you places. boost cheaper (to extent), n/a more respectable
Oops I missed the Boosting part haha. I agree with what is said above. unless using low boost I would definitely recommend the forged internals.
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hey i really appreciate the advice imma take a little bit of what everyone said and put it into play and ill post photos and stuff i got the exhaust cam as a start but im not trying to get it done quick i wanna stretch it out considering money plays a major part lol
