need help completing my 383
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need help completing my 383
alright well i emailed lloyd elliott to get help with my cam and basically my whole situation, but here's where i'm sitting right now...
i have basically a complete bottom end with the following parts...
eagle cast crank, scat i beam 4340 rods, speed pro hypereutectic pistons, plan on ordering arp main studs and the rods came with arp bolts, and my heads were also done locally by larry woodruff (along with all the machine work)
my builder told me that the lt1s that he had built spark knocked really badly when he would bump the compression up, but i'm almost positive it was because they weren't tuned correctly (if at all), so he ordered me a set of cometic gaskets at .051 thick to put the compression right at 10.5:1, which he said he thought would be safe just running pump gas, but i figure i can get some more power with a little higher compression and just wanted some opinions on where to go for that route
secondly, i have two sets of rocker arms, the SA lt4 hot cam kit gm 1.6 rockers and a set of crane gold NSA 1.6's for 7/16 stud, but i was browsing on jegs and summit and i saw that the crane golds have a setup for specifically lt1's and then another small block setup, which i'm guessing is just a wider body... can i run the standard small block rockers with stock height trimmed valve covers or even a taller set, or can i get by with running these at all? i feel like i want the added insurance of NSA
also, i was thinking about going with something along the lines of the gm847 cam, or even a custom ground cam through LE, so for my basic setup what injectors would i be safe running?
thanks
i have basically a complete bottom end with the following parts...
eagle cast crank, scat i beam 4340 rods, speed pro hypereutectic pistons, plan on ordering arp main studs and the rods came with arp bolts, and my heads were also done locally by larry woodruff (along with all the machine work)
my builder told me that the lt1s that he had built spark knocked really badly when he would bump the compression up, but i'm almost positive it was because they weren't tuned correctly (if at all), so he ordered me a set of cometic gaskets at .051 thick to put the compression right at 10.5:1, which he said he thought would be safe just running pump gas, but i figure i can get some more power with a little higher compression and just wanted some opinions on where to go for that route
secondly, i have two sets of rocker arms, the SA lt4 hot cam kit gm 1.6 rockers and a set of crane gold NSA 1.6's for 7/16 stud, but i was browsing on jegs and summit and i saw that the crane golds have a setup for specifically lt1's and then another small block setup, which i'm guessing is just a wider body... can i run the standard small block rockers with stock height trimmed valve covers or even a taller set, or can i get by with running these at all? i feel like i want the added insurance of NSA
also, i was thinking about going with something along the lines of the gm847 cam, or even a custom ground cam through LE, so for my basic setup what injectors would i be safe running?
thanks
Last edited by squeals99; 03-13-2011 at 05:51 PM.
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and for a real post, I would go with the main bolts that were installed when the machine work was done, the reason for that is that arp studs (for sure) and bolts (possibly) grip differently and would make it so the main caps to be align honed again
do a test fit on the rocker arms and valve covers, and i would go with 36 or 42 lb injectors, not 100% sure on what one out of those two
do a test fit on the rocker arms and valve covers, and i would go with 36 or 42 lb injectors, not 100% sure on what one out of those two
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yeah i dont have the NSA rockers yet, but this friday i'm pickin them up from a guy i work with and ill check from there, but i dont have valve springs yet either so just didnt know if anyone had any experience with these
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valve springs are based off of the cam used, so until you have the cam, its all speculation on what springs are gonna work for it. it depends on lift, rocker ratio, ramp rates and probably a few other things,
best bet on that is to figure out what cam your gonna use then contact the manufacturer of the cam and ask them what springs are recommended for the cam and get those.
and i would run a thinner head gasket (impala .o26 compressed thickness) i believe 10.5 is right around stock compression and that you are good up to 11.5-12.0 to one on pump gas
message me on fb if you wanna chat about this
best bet on that is to figure out what cam your gonna use then contact the manufacturer of the cam and ask them what springs are recommended for the cam and get those.
and i would run a thinner head gasket (impala .o26 compressed thickness) i believe 10.5 is right around stock compression and that you are good up to 11.5-12.0 to one on pump gas
message me on fb if you wanna chat about this
#6
I would go with a cam that Lloyd recommends. Have him get you some springs too. Make sure you install the springs to proper height. Yes you can bump up the compression. 10.5-1 is almost stock. Always run good gas in your never put shitty 87 in it. With good gas and a proper tune 11-1 is very easy to do with an LT1. Some guys go way higher than that with aggressive cams on pump gas.
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yeah i always run 93 in it, even before this whole deal happened and the car was basically stock... but would the head gaskets that are provided in just a standard felpro complete gasket set suffice, or do i need to go another route? i thought .051 was pretty damn thick lol
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you will need to get different ones this link has part numbers for different gaskets and such
great link
http://www.lt1engine.com/tech/common...-part-numbers/
great link
http://www.lt1engine.com/tech/common...-part-numbers/
#10
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You've got some serious issues to iron out.
That Eagle cast crank has to go. Use it and you're asking for trouble. There are far more failure stories than success stories with that crank - they break WAY too easily. If you're going to be doing it, do it right and get a FORGED piece.
10.5:1 compression is a step BACKWARD. You can easily have a streetable 383 closer to 12:1 compression. Mine is running at 12.7:1 with no problems. As long as you have a good tune there's no reason to run at such a low compression (and using such an expensive gasket). Regardless of what your engine builder says, tell him you want more compression. It is ALL in the tuning.
For injectors, take your estimated flywheel HP (N/A) and multiply it by .07. That will give you a good indication of your injector requirements.
That Eagle cast crank has to go. Use it and you're asking for trouble. There are far more failure stories than success stories with that crank - they break WAY too easily. If you're going to be doing it, do it right and get a FORGED piece.
10.5:1 compression is a step BACKWARD. You can easily have a streetable 383 closer to 12:1 compression. Mine is running at 12.7:1 with no problems. As long as you have a good tune there's no reason to run at such a low compression (and using such an expensive gasket). Regardless of what your engine builder says, tell him you want more compression. It is ALL in the tuning.
For injectors, take your estimated flywheel HP (N/A) and multiply it by .07. That will give you a good indication of your injector requirements.
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so whats a good forged piece that won't break the bank? i already had all this balanced already, so i really don't want to basically just throw this crank out and do it all again if ya know what i mean, but i also know what you mean about the crank i have, and i researched before hand about it and i was kinda disappointed when i saw the box that he gave me when i went to pick it up lol
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4.030 bore, 3.75 stroke, .039 compression height head gasket, .027 (non zero decked block), 5 cc piston (dished), and 54 cc cylinder heads (stock lt1 unshaved)
I got 11.76 to 1 compression ratio using
http://www.rbracing-rsr.com/compstaticcalc.html
anyone see anything wrong? and these specs are off of part numbers he gave me. other than the cylinder head cc (google)
I got 11.76 to 1 compression ratio using
http://www.rbracing-rsr.com/compstaticcalc.html
anyone see anything wrong? and these specs are off of part numbers he gave me. other than the cylinder head cc (google)
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So now I'm looking at a forged crank... thinking maybe of going with forged pistons also... are srp forged pistons a decent set to go with? Or you think I'll be alright with just the hyper ones I have? Prob won't spray it ever but I just can't make up my mind now Lol
#17
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Howards track smart,there is someone having a special on them over on racing junk.If you do forged pistons make sure they are 2618 instead of 4032 that way you can spray it if you want later on.Get the crank first so you can get the target bob weight for the balance then you can order your pistons.The CP bullet line looks pretty good,lots of different choices at a decent price.The track smart is 100% usa made.