My Katech 416 update

[lazerlemonta]

Can these 416s be spun to 76-7700? Very nice street car power Clark. The cam in that thing is very mild for a 416. It should drive like a dream with that awesome torque curve!

[Katech_Zach]

Originally Posted by lazerlemonta

Can these 416s be spun to 76-7700? Very nice street car power Clark. The cam in that thing is very mild for a 416. It should drive like a dream with that awesome torque curve!

We do not suggest that. Building a shortblock for those types of RPMs would have to be requested prior to purchase.

[lazerlemonta]

Thanks Zach. I spin my SBE LS3 7650 but i have the valvetrain for it. Only reason I was asking is the X1 intake likes a cam for RPM.

[acammer]

Zach - what is the practical RPM limit for Clarkstars short block? It might help inform the camshaft he ends up with. I still think that something in that ~235*/~255* range would make a ton more than what's in there now and still be pretty well mannered in a 416. I would think the bigger displacement might shift the range for the X1 down a bit - but it definitely is gonna want make power out to and into the 7k+rpm range.

[zz430camaro]

If you were just looking at piston speed, a 376 at 7000 rpm is the same as a 416 at 6338. Kinda gives you perspective.

[zz430camaro]

Originally Posted by lazerlemonta

Thanks Zach. I spin my SBE LS3 7650 but i have the valvetrain for it. Only reason I was asking is the X1 intake likes a cam for RPM.

Clarkstar used to spin his to over 7k regularly and spun a rod bearing.

[Clarkstar]

Originally Posted by zz430camaro

Clarkstar used to spin his to over 7k regularly and spun a rod bearing.

I've read the stock bearings aren't designed to be spun that high.... some don't have any problems. I was less fortunate...

[Katech_Zach]

Originally Posted by zz430camaro

If you were just looking at piston speed, a 376 at 7000 rpm is the same as a 416 at 6338. Kinda gives you perspective.

Originally Posted by acammer

Zach - what is the practical RPM limit for Clarkstars short block? It might help inform the camshaft he ends up with. I still think that something in that ~235*/~255* range would make a ton more than what's in there now and still be pretty well mannered in a 416. I would think the bigger displacement might shift the range for the X1 down a bit - but it definitely is gonna want make power out to and into the 7k+rpm range.

We do not spin that shortblock more than 7000rpm. With that said, that is what we suggest the limit is. If you are constantly beating on the rev limiter with any engine, you can only assume that it's life will be shortened. Obviously you can spin the shortblock faster, but you have to understand that it will decrease the life of the engine depending on how hard you run it. This is not advised.

Power depends on a lot of variables, but I would imagine increasing the intake/exhaust split from his existing cam would help up top.

[acammer]

Originally Posted by zz430camaro

If you were just looking at piston speed, a 376 at 7000 rpm is the same as a 416 at 6338. Kinda gives you perspective.

Good way to look at it. 10% more piston speed is very significant, 7000 on a 416 feels like 7700 - puts it sharply in perspective.

Call the GPI boys and let them get you where you wanna be.

[Freddy G]

I'm in the same boat, and looking for a 415/416 short block. Motor blew up after a lifter swap. Looking for the shortest lead time as possible.. Looking between CNC motorsport and texas-speed. Any suggestions base on your research and purchase experience? Thanks

[christianchevell]

Hey there! First engine I built was a stock cube ls3 with the 235/239 cam from tsp it used to be .639/.623 and 112 lsa for mine and it ran like a raped ape up top, I got with CAI and headers hfc 491 hp and 448 torque on a mustang with it....TSP redesigned as the required .675 springs were pretty stiff and the stiffer the spring the more brittle … You went with the LOD intake and the torque stayed the same and the HP went up and you should have gained most likely about 40 ft lbs had you a shorter runner intake....

Sure you gained lots of HP but ….. down low you lost out on torque that helps move you right off the bat. I also would say you should have gone with Stroker cam, the TSP cam is more a of a NOS friendly stock cube deal. Just for example I playing it safe now because my wallet caught on fire went with a mild .613/.578 cam motion cam in the 620s 114+4 more for just picking up torque and taking it easy until someday I can afford some GPI heads and cam etc....,( daughter had to be in neuroscience no shi…)…

SO heres my engine, 428 ...11 to 1 milder cam stock intake, CAI, headers ,HFC....lost a little HP gained torque all across the board and I feel it is a much stronger engine than the 235/239 engine and feel it down low its torquey... Someday things will change for me.... only a couple more years and I will have cash again as paying off college is not all I am paying off..... I will go stroker cam and its a toss up between the Airforce and a LOD intake with it being made for a ls7's heads dependent.... I have stock gmpp ported cnc ls3 heads. And this is on a Mustang tuned/done up by a LS guru. Crappy on the ink... I gained all across the board for power averages and the torque is about 375 at 2250 much more off the bat and all across the board, HP at only 476 a 15 hp loss off a much more aggressive cam but the deal is being stroked and with the right LSA I gained lots of torque...You feel the torque it launches you, it chirps and shreds and gets fishy.... And makes it nice for a daily driver for now.... the AFR on this just started to read late, the printer low on ink but hey my averages both in HP and especially torque went way up meaning I made a much more powerful engine just from stroking with a much milder cam. So I am at 483 ft lbs and 476 HP, My average power and low reading on my HP is higher also so its a basically stronger all around engine....

You have a engine just basically racing to the top for HP just what the cam wants, it out performed the Nightfury when everyone was using them a lot and my dyno may look a lot like yours had I not gone with a new cam and gone with the stock intake. I will show you my old graph, it ran great but as I said my engine and car feels faster making use of torque with this heavy chevy a lot. And someday I will go with a better intake and some bigger heads and most likely not go FI because its my daily, but I have yet to see the LOD making any torque just HP as that's what a long runner does, the MSD can make both so someday its the more likely choice for me because only making some top end HP is not a winner, winner ,chicken dinner for me as torque wins races, HP is based off it and shows how efficient the engine is way high up there but you have to get there first and moving a heavy chevy is why they go to mega torque converters etc getting it up in the power band, and for a daily I prefer to be in the band for torque without having to rev at every stop light..... thus a manual for this fun ride.
And a tunnel ram type set up benefits mostly from a real aggressive race only type cam... and can be beneficial for racing that's once your rolling its all about staying up top...

And anyway heres the old stock cube tsp 235/239 cam engine.... it made Hp right up to the end....
So just to show this old dogs knows his tricks I gained a avg. 32 ft lbs up from 409 to 441 and on avg. I gained 26 hp going from 359 to 385, not dang bad for loosing HP to gain torque with a milder cam...and I have 20 more hp and 40 more ft lbs right off the bat. And I am just playing it safe ..any car is a collection of parts, if you make them for a purpose they can be completely different and vastly different in types of performance yet still fun!!! that's what's great about hot rodding how dull would things be if we were all the same! So think about what I did for an example and my parts to help in your future if you want to learn from a old dog...… Good Luck!

[Clarkstar]

Making progress... nw 102 tb and Airaid MXP intake. DSX flexfuel sensor is on too..... just gotta get to the tuner.

[christianchevell]

Well good for you it looks nice with the black and white combo...…… Expect it to make mega HP and hopefully the torque will not disappoint yet I know just as with my engine a dedicated stroker cam would be better.....but I am waiting to do the whole GPI things after the daughter gets her Neuroscience degree...… really...LOL

[Bo White]

Not sure how I missed this but I love the fact you showed the difference between your SBE build and new build on the same dyno. Also it having the same top end parts is a bonus on the comparison between SBE and 416