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need some help and some brainstorming. I've looked at threads for the last week on this concern and can't find what I'm looking for. Any help would be appreciated. Looking for lost power and torque. Old setup was 243, LS6 intake, vrx4 cam. New is tf 220, dorman ls2, vrx4 cam. If I compare to the rest of the internet, I think I'm down about 30-50whp. The curve is the same, just low in my opinion. The only comparison I have is a c5z with just a cam made 430/390. Same dyno and tuner that I was on. Anything look out of place here. I appreciate and input and ideas, thank you!
What cc are the heads? I'm not familiar with that intake but using a fast 102 for example and say you left them at 64cc I would expect at least 430+. If they were milled to 59cc then I would expect between 450-470 on 93 octane
I'm planning on going to the track next wedsday. I did a cranking compression test and got results of 145-150 psi. Not sure if that tells me anything. Thanks
I did have it tuned, yes. Not sure what fuel pressure is at WOT. 36lb an hour injectors. Not sure if I could log those since I don't have software but I may be able too. What kind of values would I be looking for?? Thank you!
Borrowed the scan tool from my work and logged some things. I don't know what they mean tho. Basically from 2500 to 6500 the MAP is at 14 psi. MAF starts and .19 lbs and climbs to .49 lbs by the end. No knock retard and spark was 26 degrees. Does any of this help? Thank you in advance.
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
do you have headers??... if I'm reading the graphs right you went from about 375/360 to 400/375 by swapping heads and intakes?... or did you lose power after swapping heads/intakes?
Is the yellow line on the graph before you installed the heads?
little details like push rod length, using the right springs and so on can add up, are you using the springs that came with the heads? I think their for heavier roller rockers but I could be wrong, what rocker arms are you using?
I'm running the tfs 215, the tfs heads are good heads and make good power, the 220's are very close power wise
what throttle body are you running, ls2, if your still running the stock one that could be choking it down, do you have aftermarket air intake
do you have headers??... if I'm reading the graphs right you went from about 375/360 to 400/375 by swapping heads and intakes?... or did you lose power after swapping heads/intakes?
I have 1 3/4 inch stainless works headers and x-pipe. 375/360 was cncd 243's and LS6 intake. 400/375 was tfs and dls2. Thank
Is the yellow line on the graph before you installed the heads?
little details like push rod length, using the right springs and so on can add up, are you using the springs that came with the heads? I think their for heavier roller rockers but I could be wrong, what rocker arms are you using?
I'm running the tfs 215, the tfs heads are good heads and make good power, the 220's are very close power wise
what throttle body are you running, ls2, if your still running the stock one that could be choking it down, do you have aftermarket air intake
I measured for pushrod length and put in tfs 7.500. Using stock rockers with trunnion upgrade. Using an ls2 throttle body. And o have a black wing. Thanks!
IMO, the only unfamiliar item is the Dorman intake. Might try swapping the LS6 back in and see if you get the power back. Also, do you know the duty cycle of the injectors or did you install larger?
Last edited by vettenuts; Jul 8, 2017 at 07:39 AM.
IMO, the only unfamiliar item is the Dorman intake. Might try swapping the LS6 back in and see if you get the power back. Also, do you know the duty cycle of the injectors or did you install larger?
unfortunately, I sold the intake already. Oops. I have 36lb injectors. Thanks.
Power curve
