Summit racing k6401 camshaft

[shovelluv]

http://www.summitracing.com/parts/sum-k6401/overview/make/plymouth

I was wondering if anyone was running this summit racing k6401 brand camshaft. Dont want too much but a little over stock. Like the specs for the price on a budget build 383 i am doing. Stock intake , headers, rebuilt 906 heads. 750dp.

 

[HT413]

Seems to me the lift is reasonable but the duration is what makes a cam 'big', not the lift. And at 298/303 adv. duration, that's a pretty big cam for a 'mild' street car - WAY over stock.

- - - Updated - - -

Specs say it is a mild bracket cam, and that's exactly what it is. Have a look at comp's magnum muscle cam, which I believe is a 268 adv duration or even the high energy cams which are a little more aggressive. the smaller high energies still have adv duration in the 250's and 260's range, which is perfect for a hot street car.

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=CTGY&Store_Code=CC&Category_Code=WDGCAMhydFTXE

 

[shovelluv]

Yeah, i see lobe seperation is 114 deg. also, little much. I do believe the factory HP cam was a 115 deg. lobe seperation with alot less duration. I think im going to go with the xe268H cam. Things i dont want.... Rich idle, low vacuum and bad low end performace. It will be used in a street cruser next summer.

 

[lewtot184]

actual duration measured at .006" lift is 280/290. they are ground on 114 lobe centers with 2 degrees of advance. they have about 10 degrees more duration at .050" and .200" lobe lift. this gives them a little more effective duration than the stock magnum cam. i have one in a stock 440 magnum and really like it. the idle is smooth, doesn't require any distributor mods, torque converters, or gears and gobs of torque. i think it's a better cam than the magnum cam for a stock type rebuild. i also believe it's a crane hp280/290, very similar to the hmv278.

 

[Meep-Meep]

The 114 LSA will give very good vacuum and drivability. From what I see in the specs you can't get hurt using this cam in your application. For a driver 383 I'd run a smaller carb like a 625 or 650. I'm running the MoPar .455 / 272 on a 112 LSA in a 440 and it's fantastic.

 

[motorparts92]

Put it in my 78 power wagon 440 after original cam wore out, MUCH more throttle response than the eco-friendly granny cam that was in it, plus it seems to use LESS Fuel!?!? Should be very street friendly and peppy, expecially for a car!

 

[MoparMitch]

I'm trying something a little different in my GTS 383 build. Using a Howards 721941-12 Hyd. It is 271/281 duration with 518/543 lift. The really cool thing is that its ground on a 112 LSA. Howards also takes maximum advantage of the .904 lifter bore. Especially with the high ramp speed of this camshaft. Howards has some pretty cool/different stuff.

 

[shovelluv]

Well thanks for all the replys, I decided to try one now and replace what was currently in my factory 383 70 rr, which was a mystery cam and only good after 2000 rpm. After i installed and broke in the new K6401 cam Sunday, I couldn't be happier! Excellent vacuum, cleaner smooth idle, excelleration and power thru the whole range of the engine. it sounds great. I am also running 1800 stall in my 727.

 

[Josh wooten]

Well thanks for all the replys, I decided to try one now and replace what was currently in my factory 383 70 rr, which was a mystery cam and only good after 2000 rpm. After i installed and broke in the new K6401 cam Sunday, I couldn't be happier! Excellent vacuum, cleaner smooth idle, excelleration and power thru the whole range of the engine. it sounds great. I am also running 1800 stall in my 727.

Was that cam have any lope sound at all cause my son is building a 440 for his 66 barracuda and bought the same cam he rebuilt complete motor using flattop pistons 1.5 rolker rockers 452 stock heads pocket ported and bigger valve springs 780 Holley carb and torquer 2 intake he wanted a lopey sounding motor and was so hoping that cam will give him what he wants

 

[lewtot184]

Was that cam have any lope sound at all cause my son is building a 440 for his 66 barracuda and bought the same cam he rebuilt complete motor using flattop pistons 1.5 rolker rockers 452 stock heads pocket ported and bigger valve springs 780 Holley carb and torquer 2 intake he wanted a lopey sounding motor and was so hoping that cam will give him what he wants

the 6401 doesn't lope.

 

[IQ52]

As to idle quality.....I would read the reviews at the bottom of this page. Everyone there has used this camshaft.

https://www.summitracing.com/parts/sum-6401

 

[Mike67]

Not sure what your sons build is ( street I'm guessing..???) but I would scrap the Torker intake, its effective rpm range doesn't match the cam. Go with a dual plane like an rpm or what ever your flavor of choice is. It will give you better low end ( where he will probably spending most of the time) and work well when above 5200.

 

[furryfrog]

That cam doesn't lope but you can tell it is not stock. I actually just pulled that cam out of my engine, I liked the cam, and it performed really well when my turbo's spooled up, with the right converter I would be very happy with this cam, but my car is a daily driver and my mpg was about 8 in the city with this cam and it ran a little hotter than I would like. Power brakes were ok with the cam. I have a comp 268h in now.

Pulled it out after a year and looks brand new, nice and easy on the valve train, was using the summit lifters as well with this cam, the whole package is good value IMHO.

If sound is important,You tube is great to hear different cam sounds, do searches for different grinds, and comp has a lot of sound clips for some of their cams.

Funny, when I was looking into this cam last year I don't think I found this thread.

 

[khryslerkid]

was using the summit lifters as well with this cam,

Hey furryfrog, I'm glad you posted. The only thing that I was concerned about using this cam, was the lifters that they supplied. The build has been finished for awhile now, just haven't fired it up yet. Glad they worked ok for you.

Is the 268 running any cooler?

 

[IQ52]

Was that cam have any lope sound at all cause my son is building a 440 for his 66 barracuda and bought the same cam he rebuilt complete motor using flattop pistons 1.5 rolker rockers 452 stock heads pocket ported and bigger valve springs 780 Holley carb and torquer 2 intake he wanted a lopey sounding motor and was so hoping that cam will give him what he wants

The minor gains on the top end by retarding that cam will have even bigger losses on the bottom. Your problem is exactly why god (lower case "g") made Whiplash ($165) and Thumper cams ($180). They are for lower compression engines that want a lope. Come on, what is the budget? We're wasting our time, we can dance around this all day long, but if we don't know what you can afford to do, we really cannot help you.

 

[furryfrog]

Hey furryfrog, I'm glad you posted. The only thing that I was concerned about using this cam, was the lifters that they supplied. The build has been finished for awhile now, just haven't fired it up yet. Glad they worked ok for you.

Is the 268 running any cooler?

yes the comp 268h (21-215-4) runs much cooler than the summit 6401, and I'm guessing 12mpg now in the city. Builds boost about 200 rpm sooner than the summit cam though of course less power above 5000rpm. I tend to shift at about 5000 rpm now, where as the summit cam would pull hard to redline at 6000rpm, was going to bump my redline to 6400 but ended up swapping the cam out. I'm keeping the summit cam, chances are it will end up back in the car someday. If it was a weekend car I still would be running it.

 

[lewtot184]

if it means anything; peak power in the 440 in my r/t with the 6401 cam was about 4800rpm with 5000rpm being a stretch. this is an engine with stock carb/intake manifold, stock exhaust, 9.3:1 compression. idle was 13" in gear (stock converter). idle was very smooth warmed up and low speed and mid-range torque was excellent. there is a 112LSA version of this cam with 5 degrees of advance out there if anybodies interested.

 

[Malicious]

The minor gains on the top end by retarding that cam will have even bigger losses on the bottom. Your problem is exactly why god (lower case "g") made Whiplash ($165) and Thumper cams ($180). They are for lower compression engines that want a lope. Come on, what is the budget? We're wasting our time, we can dance around this all day long, but if we don't know what you can afford to do, we really cannot help you.

Thats why I brought the Whiplash for my 'make do' low comp engine. The sounds is just orgasmic! Not great for power brakes tho...