Nice. I've got 100 miles on my 347. Comp cams 31-238-3 flat tappet seems to make it streetable and lively. Shame its started to wipe cylinder 8 inlet lobe. I decided to pull the inlet off to check how it's wearing in and there's a wierd spirally pattern around the edge of that one lifter that doesn't match all the others. I used comp break in additive, oil change after 30 mins 1500-2500 rpm run time. Quality zddp oil. Spring pressures 145lb, not coil bound, stem seals have clearance, correct length pushrods all flowing oil and spinning. Importing this stuff into the UK Costs a fortune, takes weeks and I have no idea if I have a job or not due to lockdown so that's that. I don't have another £500 to spend on another cam, lifters, timing cover gaskets, oil, break in additive and filter. Gutted. I'd love to know if comp cams and lifters are USA made or Chinese as that will certainly sway my next cam purchase decision.
@@martinellul1604 sold a spare 4 cyl engine I'd been tripping over for years, bought new same spec comp cam. I cheaped out on lifters when I was doing the build, the suppliers listed standard or premium. I went premium this time, the ones with circlip retainers. I did the inner spring thing as you advised and now after break in and a few road miles it's silent. Phew. Glad I caught it before any swarf went through the bearings.
Hello Richard, thanks for all the good information you always bring us. I'm a big fan. What do you think about Comp Cams Thumpr cams( all 3 variants) for a roller 347 sbf? Thanks for everything and keep up the good work. Jo
Love these Comp "stroker" cams ... Yet Motor Trend has an article from a few years ago using XE266 to 282hr cams.... And the output on a 347 was in the same ballpark. 266 favoring overall torque, and 282 top end. So why do I need an XFI cam to make about the same power curves as an XE-HR??
On my 3:49 the camshaft I am running is a Howard cam it is 239/241 due. 581 lift 110 lobe separation 106 Centerline I noticed on the Comp Cam it had a 114 lobe separation do I need a wider lobe separation for the 347 or 40 over which would be 349 .Now with this camshaft same everything else quarter mile my car runs 5 miles an hour slower ET is there but my mph is off any help would benefit I did have a Comp Cam and it was 112 lobe separation duration and lift was pretty close to the Howard
Is there some formula for figuring out when duration is matched to the new larger cubic inch stroker. I'm building a 471 mopar, my cam choice is a howards solid flat with 260 in & 264 exh duration at .050 Lift numbers are 616in & .620 exh. I'm just trying to figure out what my extra 71 cubes does to tame it down? Would it be like 10 degrees or ??? Let me know Richard, thanks man !
@@Moparmaga-1 10.5 to 1 and a $2800 port job performed by Hughes Engines on a set of Engine Quest cast iron Magnum replacement heads. I used a Magnum block with a set of AMC flat tappet solid lifters. Scat forged rotating assembly with a set of custom forged dish pistons made to Hughes Engines specs. The pistons had a quench pad that had a positive deck height and had to be machined to fit the Magnum heads. These pistons with that quench pad was the key to making the HP this engine made.
@@bigboreracing356 I have 11.5 compression & my trick flows are cleaned up (cnc tool ridges) flow 30 cfm over advertised. 355 cfm, yet to assemble & Yet to dyno. I'm copying another guys build that ended up making 750, I'm a couple things different, no roller & no 5k oiling system.
Once you cross the 600hp line in the sand...they dont last too long....i split 2 late model blocks right down the center...before i picked up a (new) Boss 302 block...
![Дон ДОН, Алаудинов и СБЕЖАВШИЕ из под Курска ахматовцы 😁 [Пародия]](http://i.ytimg.com/vi/dEfCf5IK26Q/mqdefault.jpg)
I wonder about the very wide LSA. As per David Vizard.
Good old nitrous, always good for big torque. 👍🏻
Nice. I've got 100 miles on my 347. Comp cams 31-238-3 flat tappet seems to make it streetable and lively. Shame its started to wipe cylinder 8 inlet lobe. I decided to pull the inlet off to check how it's wearing in and there's a wierd spirally pattern around the edge of that one lifter that doesn't match all the others. I used comp break in additive, oil change after 30 mins 1500-2500 rpm run time. Quality zddp oil. Spring pressures 145lb, not coil bound, stem seals have clearance, correct length pushrods all flowing oil and spinning.
Importing this stuff into the UK Costs a fortune, takes weeks and I have no idea if I have a job or not due to lockdown so that's that. I don't have another £500 to spend on another cam, lifters, timing cover gaskets, oil, break in additive and filter. Gutted. I'd love to know if comp cams and lifters are USA made or Chinese as that will certainly sway my next cam purchase decision.
Need to remove inner valve spring for cam run in
@@martinellul1604 sold a spare 4 cyl engine I'd been tripping over for years, bought new same spec comp cam. I cheaped out on lifters when I was doing the build, the suppliers listed standard or premium. I went premium this time, the ones with circlip retainers. I did the inner spring thing as you advised and now after break in and a few road miles it's silent. Phew. Glad I caught it before any swarf went through the bearings.
@@chasevans7171 Awesome, great to hear
Makes a strong case for drain plug and oil filter magnets👍👍😎
Hello Richard, thanks for all the good information you always bring us. I'm a big fan. What do you think about Comp Cams Thumpr cams( all 3 variants) for a roller 347 sbf? Thanks for everything and keep up the good work.
Jo
Love these Comp "stroker" cams ... Yet Motor Trend has an article from a few years ago using XE266 to 282hr cams.... And the output on a 347 was in the same ballpark. 266 favoring overall torque, and 282 top end. So why do I need an XFI cam to make about the same power curves as an XE-HR??
I installed a XE266HR-12 and used 1.7 rockers, which helped increased lift and duration and lessen lobe seperation on a 390W
What’s the best 347 stroker kit to get that would last longer?
On my 3:49 the camshaft I am running is a Howard cam it is 239/241 due. 581 lift 110 lobe separation 106 Centerline I noticed on the Comp Cam it had a 114 lobe separation do I need a wider lobe separation for the 347 or 40 over which would be 349 .Now with this camshaft same everything else quarter mile my car runs 5 miles an hour slower ET is there but my mph is off any help would benefit I did have a Comp Cam and it was 112 lobe separation duration and lift was pretty close to the Howard
What are the specs on the heads?
Try this with a 248 cam!!
Is there some formula for figuring out when duration is matched to the new larger cubic inch stroker.
I'm building a 471 mopar, my cam choice is a howards solid flat with 260 in & 264 exh duration at .050
Lift numbers are 616in & .620 exh. I'm just trying to figure out what my extra 71 cubes does to tame it down? Would it be like 10 degrees or ??? Let me know Richard, thanks man !
I built a 408 Chrysler and used a flat tappet cam from Hughes Engines similar to your cam.
It made 575 HP.
You will make the same power at a lower RPM
@@bigboreracing356good to know what compression & heads did you have ?
@@Moparmaga-1 10.5 to 1 and a $2800 port job performed by Hughes Engines on a set of Engine Quest cast iron Magnum replacement heads.
I used a Magnum block with a set of AMC flat tappet solid lifters.
Scat forged rotating assembly with a set of custom forged dish pistons made to Hughes Engines specs.
The pistons had a quench pad that had a positive deck height and had to be machined to fit the Magnum heads.
These pistons with that quench pad was the key to making the HP this engine made.
@@bigboreracing356 I forget what those things flow ? 300 or so cfm?
@@bigboreracing356 I have 11.5 compression & my trick flows are cleaned up (cnc tool ridges) flow 30 cfm over advertised. 355 cfm, yet to assemble & Yet to dyno.
I'm copying another guys build that ended up making 750, I'm a couple things different, no roller & no 5k oiling system.
So what's the secret? Call comp?
That's not a secret ;)
Didn't think a 302 block could handle that much hp?
It cant handle supercharged pressure.
Once you cross the 600hp line in the sand...they dont last too long....i split 2 late model blocks right down the center...before i picked up a (new) Boss 302 block...
Cant go past 549 hp on stock 302 block or it will split up the middle 😎
@@GJ-DT
I heard it was 546hp....🙂
Frankie Ford i heard it was 540HP
I love to make zex to ze ladiez
why talk with your hands so much put your hands down please you’re making me nervous