I can return Performer package!
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Elder User
Joined: Sep 2004
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From: Grain Valley Mo.
I can return Performer package!
Summit said yes.................... I think you guys are right, as long as I'm doing this I might as well get some more power. Mine is a little bit different than the 360 we worked on the other day. A 1976 truck motor, 390 +.030, stock pistons and heads. A C6 trans with a 9 in. with 3.0 gear. This is in a 53 F100. I'm sold on the RPM, the hardest part for me is picking the right cam. I don't want to change the stock converter or the high gear. It would be nice to have a little bit of cam lope. As long as I'm dreaming, how about good gas mileage. 
Wow, I must be dreaming, great power, good milage, race car idle, stone cold reliable!!!---- What cam do you guys think? I already have a HV Melling pump, and ARP shaft, and I'm going to use the Holly jets for restrictors. What else do I need? Thanks guys.......
Wow, I must be dreaming, great power, good milage, race car idle, stone cold reliable!!!---- What cam do you guys think? I already have a HV Melling pump, and ARP shaft, and I'm going to use the Holly jets for restrictors. What else do I need? Thanks guys.......
Lead Driver
Joined: Apr 2001
Posts: 6,175
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From: Texas
Wake up!!!
I think yo ualready know the answer. A cam that provides a lope at idle will not typically like your low gear ratio or a stock torque converter. Mileage can be decent with matched components. But, a bigger cam will also require valve-train upgrades (read, mo money). The main thing to consdier is your compression ratio. If you have .030 over stock truck pistons, you may have a low compression ratio, which doesn't work well with the bigger cams. Are you planning to get the RPM heads as well?
I think yo ualready know the answer. A cam that provides a lope at idle will not typically like your low gear ratio or a stock torque converter. Mileage can be decent with matched components. But, a bigger cam will also require valve-train upgrades (read, mo money). The main thing to consdier is your compression ratio. If you have .030 over stock truck pistons, you may have a low compression ratio, which doesn't work well with the bigger cams. Are you planning to get the RPM heads as well?
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Elder User
Joined: Sep 2004
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From: Grain Valley Mo.
Hi there gtex... no I don't know the answer. Let me take my tongue out of my cheek and try again. I was told on this thread that my choice of the Performer-Plus package was crap, that I should buy the RPM. Several Crane cams were mentioned to Edge for his 360. I thought maybe someone would know what would work good for my 390. I'm just a rookie but why would compression be lower on a over bored motor? It seems it would be pushing more air into the same size combustion chamber thus raising compression. Thanks............
FE "Freakin Expensive"
Joined: Dec 2003
Posts: 6,461
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From: Smith Mountain Lake, VA
Originally Posted by xfordman
Hi there gtex... no I don't know the answer. Let me take my tongue out of my cheek and try again. I was told on this thread that my choice of the Performer-Plus package was crap, that I should buy the RPM. Several Crane cams were mentioned to Edge for his 360. I thought maybe someone would know what would work good for my 390. I'm just a rookie but why would compression be lower on a over bored motor? It seems it would be pushing more air into the same size combustion chamber thus raising compression. Thanks............
Now if it had .030" car pistons put in it...the CR would be higher and might Support a nicer Cam.. What Greg was saying..A heavy Truck and a Low CR motor a Good size bump stick..your going to loose Bottom end Torque..and with Freeway Flyer's in the rearend...your gonna what all the torque you can get at the bottom end..Unless you change rear gears..
Get your CR up where you So can build some low end HP and TQ.....in a Truck..I wouldnt run anything under a 3.50 rear gear.. My F250 is on a Diet and is around 4400lbs right now with more to go...and I run 3:73's but I also turn a 33" tire too..I think Cruise at 65mph is about 2700rpm... But I dont Give a Damn about gas Mileage either...I have a 34mpg Grocery getter for that!! LOL!!
Good Luck!!
Russ
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Joined: Apr 2001
Posts: 6,175
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From: Texas
Sorry, I wasn't clear earlier. And I wasn't trying to be a smart-**** :-)
I'm usually a proponent of the RPM package. But, if you don't have the compression ratio to support a bigger cam, then it might not show much improvement. Especially in a vehicle with low gear ratio, auto tranny with stock style torque converter.
I used to push for the RPM package in most cases (and I still think the intake is a reasonable compromise allowing for future growth on a mild engine), but thanks to folks like Rusty70F100, I now realize how important the compression ratio, CR, is in building an engine. The CR is a major factor in picking a cam and a cam is a major factor in picking the rest of the engine, especially intake, heads and carb!
I'm with Russ on the gears. Trucks should not be any lower than 3.50 in my opinion. I think the mileage improvements are negligible. Trucks are so aerodynamically challenged they really needs to be a little higher in the power band. my 2 cent opinion.
So, in closing: get the Performer package for an otherwise stock truck 390! or plan on upgrading the pistons, heads, intake etc. to compliment a bigger cam.
I'm usually a proponent of the RPM package. But, if you don't have the compression ratio to support a bigger cam, then it might not show much improvement. Especially in a vehicle with low gear ratio, auto tranny with stock style torque converter.
I used to push for the RPM package in most cases (and I still think the intake is a reasonable compromise allowing for future growth on a mild engine), but thanks to folks like Rusty70F100, I now realize how important the compression ratio, CR, is in building an engine. The CR is a major factor in picking a cam and a cam is a major factor in picking the rest of the engine, especially intake, heads and carb!
I'm with Russ on the gears. Trucks should not be any lower than 3.50 in my opinion. I think the mileage improvements are negligible. Trucks are so aerodynamically challenged they really needs to be a little higher in the power band. my 2 cent opinion.
So, in closing: get the Performer package for an otherwise stock truck 390! or plan on upgrading the pistons, heads, intake etc. to compliment a bigger cam.
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From: Grain Valley Mo.
Russ, thanks for your input, I really appreciate you taking the time to explain things.
Greg, thank you too, no offense taken. Sorry to hound you guys over this Performer thing. I used that package on two motors and I liked them both. The other times I changed cams they sounded good but didn't perform well. I never even considered CR, I just assumed the cam was just to big. Now I can see that the cam was to big for the CR. Thanks again...........
Greg, thank you too, no offense taken. Sorry to hound you guys over this Performer thing. I used that package on two motors and I liked them both. The other times I changed cams they sounded good but didn't perform well. I never even considered CR, I just assumed the cam was just to big. Now I can see that the cam was to big for the CR. Thanks again...........
