C5Z 430" build thread... ERL, PRC, SRD, DLRE.
#62
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Those small bore PRC 265's do have a 62% exhaust ratio, so in order to capitalize on the LLSR cam, I would imagine a larger exhaust bias is necessary to get it to carry into the upper rpms available with such a combination. The MSD and larger headers/better exhaust will help.
If I remember right, you were having trouble with valve float preventing you from even seeing what the current combination is really capable of in the upper rpms.
I wouldn't be so hasty to change cams or say the cam is incorrect until it is tested with the MSD and better exhaust, with the valves under control.
If I remember right, you were having trouble with valve float preventing you from even seeing what the current combination is really capable of in the upper rpms.
I wouldn't be so hasty to change cams or say the cam is incorrect until it is tested with the MSD and better exhaust, with the valves under control.
#64
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Those small bore PRC 265's do have a 62% exhaust ratio, so in order to capitalize on the LLSR cam, I would imagine a larger exhaust bias is necessary to get it to carry into the upper rpms available with such a combination. The MSD and larger headers/better exhaust will help.
If I remember right, you were having trouble with valve float preventing you from even seeing what the current combination is really capable of in the upper rpms.
I wouldn't be so hasty to change cams or say the cam is incorrect until it is tested with the MSD and better exhaust, with the valves under control.
If I remember right, you were having trouble with valve float preventing you from even seeing what the current combination is really capable of in the upper rpms.
I wouldn't be so hasty to change cams or say the cam is incorrect until it is tested with the MSD and better exhaust, with the valves under control.
NAVY made some nasty power! Where did I go wrong?! Lol
#65
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All of that back and forth turned out to be ignition wiring on the dyno? Weren't you chasing what you thought was valve float for months? Either way, I am glad it is straightened out. I don't know why I thought this was LLSR, I specifically remember thinking that the ~.630" lift cam is getting danger zone close to stock rockers' ability to maintain proper geometry, but Martin definitely knows more than I do. And stock rockers [generally] mean you're using a hydraulic cam.
You will probably see it carry further with your larger headers. 1-3/4" headers on the engine dyno choke your 430ci motor way more than they choke NAVY's 394ci motor. It's not a matter of what you did wrong, sir. For one, there will always be someone better. And secondly, NAVY's combination is just incredibly well matched through and through. He has lower bearing speed, thinner rings, higher rod ratio, just a whole lot right about his particular setup.
Just wait until you get your 430" tuned with the intake and exhaust the cam was spec'ed for. I am sure you will not be disappointed.
You will probably see it carry further with your larger headers. 1-3/4" headers on the engine dyno choke your 430ci motor way more than they choke NAVY's 394ci motor. It's not a matter of what you did wrong, sir. For one, there will always be someone better. And secondly, NAVY's combination is just incredibly well matched through and through. He has lower bearing speed, thinner rings, higher rod ratio, just a whole lot right about his particular setup.
Just wait until you get your 430" tuned with the intake and exhaust the cam was spec'ed for. I am sure you will not be disappointed.
#66
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All of that back and forth turned out to be ignition wiring on the dyno? Weren't you chasing what you thought was valve float for months? Either way, I am glad it is straightened out. I don't know why I thought this was LLSR, I specifically remember thinking that the ~.630" lift cam is getting danger zone close to stock rockers' ability to maintain proper geometry, but Martin definitely knows more than I do. And stock rockers [generally] mean you're using a hydraulic cam.
You will probably see it carry further with your larger headers. 1-3/4" headers on the engine dyno choke your 430ci motor way more than they choke NAVY's 394ci motor. It's not a matter of what you did wrong, sir. For one, there will always be someone better. And secondly, NAVY's combination is just incredibly well matched through and through. He has lower bearing speed, thinner rings, higher rod ratio, just a whole lot right about his particular setup.
Just wait until you get your 430" tuned with the intake and exhaust the cam was spec'ed for. I am sure you will not be disappointed.
You will probably see it carry further with your larger headers. 1-3/4" headers on the engine dyno choke your 430ci motor way more than they choke NAVY's 394ci motor. It's not a matter of what you did wrong, sir. For one, there will always be someone better. And secondly, NAVY's combination is just incredibly well matched through and through. He has lower bearing speed, thinner rings, higher rod ratio, just a whole lot right about his particular setup.
Just wait until you get your 430" tuned with the intake and exhaust the cam was spec'ed for. I am sure you will not be disappointed.
#67
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FRiCK
You should reach your performance goals for less than 1/2 what I
Have in my Engine when all is said and done. Seriously though
Save yourself the time and expense and have Tony port your
MSD before you put it on the first time. You have a very good
Power & torque curve which will only improve with the 1 7/8"
LTs, MSD, & NW 102.
You should reach your performance goals for less than 1/2 what I
Have in my Engine when all is said and done. Seriously though
Save yourself the time and expense and have Tony port your
MSD before you put it on the first time. You have a very good
Power & torque curve which will only improve with the 1 7/8"
LTs, MSD, & NW 102.
#68
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Frick, given that you are rocking a 'vette, have you considered a set of those sexy AFE/PFADT tri-y headers and X-pipe? Besides the fact that they cost more than a mortgage payment, I honestly think the scavenging would help the exhaust side of those heads quite a bit. I'm really good at spending other people's money, though.
#69
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Updating this because I'm bored. Motor has been on the garage floor, fogged with wd40. I'm back on the project! I recently sent my heads to Venom Racing Engines for a freshen up. He opened the throats from 89% to 90.5%, cut a new (improved) valve job from what came from TSP, exhaust guides were a tad tight and intakes were in spec (heads have about 8k miles on them), we also went ahead and knocked .033" of the heads for compression ratio of 12.5:1, got some .040" cometics to tighten up my quench a bit at .041"... for fuel we've got watered down 91 here in CA, so I'll also be using straight meth alky inection.
Also went ahead and ported my MSD after lot of reading and such. It came out pretty awesome for zero dollhairs invested lol... the MSD is atrocious from the factory and it's no surprise to me these things pick up huge from clean up, the injector was spraying at a wall...
After I get the heads back from Venom I will be getting the car put back together and in for a tune. For the tune I'll be using Nate at Starkweather performance in Turlock, best in Nor Cal as far as I'm concerned. Fingers crossed for a legitimate 620-640hp/540-550tq rw and plan on pulling it to 7200ish.
Also went ahead and ported my MSD after lot of reading and such. It came out pretty awesome for zero dollhairs invested lol... the MSD is atrocious from the factory and it's no surprise to me these things pick up huge from clean up, the injector was spraying at a wall...
After I get the heads back from Venom I will be getting the car put back together and in for a tune. For the tune I'll be using Nate at Starkweather performance in Turlock, best in Nor Cal as far as I'm concerned. Fingers crossed for a legitimate 620-640hp/540-550tq rw and plan on pulling it to 7200ish.
Last edited by FRiCK; 02-18-2018 at 04:22 PM.