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Finally an answer to MOPAR performance valve springs

18K views 24 replies 10 participants last post by  SickToo 
#1 ·
i just got off the phone with a mopar performance parts specalist concerning these performance springs .im going to use them in my 6.4 cam swap in my 5.7 and saving $$.
google this P5160074 mopar performance spring kit. perfect for my build . then google this mopar part number 68277306AA. yup ! was was right this is the same spring used in P5160074. the difference is the kit is $230 and the same spring sold individually is $5.00 x 16 is $ 80 . $150 saved . i never could understand the ridiculously high cost the other guys sell, not to knock them but way overpriced .a simple cam swap like the 6.4-5.7 or even the comp 270,274 they would be fine but dont quot me on those. thanks for reading.

also im researching the confusion on the true part number on the beefy newer hellcat lifters .i have 2 different part numbes on those as well. 5038784AC and 5038787AC chime in if you have the answer big price diff .im close to an answer ,will post when i sort it out .
 
#5 ·
Factory rods. The oems are plenty strong enough. The 5.7 and 6.4 uses the same rods.if they can handel 392 cam which they do with no issues np in 5.7 with a 392 cam. I change my rods with oems about 30k ago cause i had about 80k on my original's and i was replacing the valve seals so i figured they were cheap enough.
I could not find an direct answer on the lifters.
I just got the
5038784AD they are much cheaper i paid
$ 325 for all 16 including racks
The
5038787AC
Are like $55 for 1 lifter
And are on national back order and seem to be disappearing .
They both fit 05 and up and both are listed for a hellcat. Go figure i have no idea whats going on with them and nobody at any of the dealers do either.
Im done with those dam things ? besides no way was i paying over $900 for the 87 ones.
 
#6 ·
Factory rods. The oems are plenty strong enough. The 5.7 and 6.4 uses the same rods.if they can handel 392 cam which they do with no issues np in 5.7 with a 392 cam. I change my rods with oems about 30k ago cause i had about 80k on my original's and i was replacing the valve seals so i figured they were cheap enough.
I could not find an direct answer on the lifters.
I just got the
5038784AD they are much cheaper i paid
$ 325 for all 16 including racks
The
5038787AC
Are like $55 for 1 lifter
And are on national back order and seem to be disappearing .
They both fit 05 and up and both are listed for a hellcat. Go figure i have no idea whats going on with them and nobody at any of the dealers do either.
Im done with those dam things [emoji2957] besides no way was i paying over $900 for the 87 ones.
Yeah i mean a nice set of Johnson lifters are around $700 i think.
 
#9 ·
no these are not factory 6.4 springs .these are "mopar performance springs" P5160074 .they will work on the 6.4 but need shims. they cost around 230 .but i found out they are they are the same as this number 68277306AA sold individually . at 4.50 a spring.
if you google the part number you will see.
they work fine no issues. i used my 5.7 rods,retainers and locks. they say can be used .in my opinion its a waist to spend any more for all that .its only a 6.4 cam nothing extreme . besides the 5.7 uses the same as the 6.4 . same ,rods ,retainers ,locks . so not sure why you would have to go beefier ? the 6.4 makes more power .
my engine is done 6.4 cam in my 5.7 , all i did was cam ,new lifters,bbk shorties, and a good tune. i have a wide band so my tuner guy was easily able to dial it in.
engine runs very strong now. above 4k wot wow ! it pulls hard all the way up to 65k . seems to want to keep going ,but i dont push it. rev is at 65k but i shift around 63k . its night and day compared to my 5.7 cam.
 
#14 ·
my engine is done 6.4 cam in my 5.7 , all i did was cam ,new lifters,bbk shorties, and a good tune. i have a wide band so my tuner guy was easily able to dial it in.
engine runs very strong now. above 4k wot wow ! it pulls hard all the way up to 65k . seems to want to keep going ,but i dont push it. rev is at 65k but i shift around 63k . its night and day compared to my 5.7 cam.
yours confirms what I've said for several years - put that cam in the 5.7 and its a different animal, yet will live in day to day traffic with great drivability.

Its even better to lose that WOT dip that you get ~ 3.5K with the stock 5.7 cam
 
#20 ·
This thread was very helpful for me thanks for posting up your findings. I’m doing a 6.4 swap in a 5.7 and I’m using this info to help complete the job.


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