Are you all seeing an influx of over cammed combinations?

General engine tech -- Drag Racing to Circle Track

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digger
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Re: Are you all seeing an influx of over cammed combinations?

Post by digger » Sat Oct 28, 2017 6:58 pm

Which factory Honda NA engine would that be ?

Seems like others do vvt type systems that appear to work better , atleast the engines seem to have more VE low to midrange

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Re: Are you all seeing an influx of over cammed combinations?

Post by joe 90 » Sat Oct 28, 2017 7:27 pm

That was just numbers pulled from a 1.6 mivec.
Honda VTEC makes near enough the same.

If you take a look at Mtsubishi's flagship N/A, the Evo Pajero, that's 400 ish nm from 3.5 litres.

84 ft lbs per litre.

So if it was a 6 litre V8, that would compare to 500 ft lbs, again all the way from idle to 8000 + RPM

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Re: Are you all seeing an influx of over cammed combinations?

Post by digger » Sat Oct 28, 2017 7:57 pm

joe 90 wrote:
Sat Oct 28, 2017 7:27 pm
That was just numbers pulled from a 1.6 mivec.
Honda VTEC makes near enough the same.

If you take a look at Mtsubishi's flagship N/A, the Evo Pajero, that's 400 ish nm from 3.5 litres.

84 ft lbs per litre.

So if it was a 6 litre V8, that would compare to 500 ft lbs, again all the way from idle to 8000 + RPM
looked and didnt find any factory versions of 6G75 with that torque figure let alone 6G74. 4G9 is 77ft-lb at 7000rpm

same with honda, one of the k24W7 was 76ft-lb/L. other systems besides vtec and mivec were doing better than that in the 90's at the low rpm to. so yet to see where the honda makes 80ftlb/l from idle to 8000rpm

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Re: Are you all seeing an influx of over cammed combinations?

Post by joe 90 » Sat Oct 28, 2017 8:11 pm

6G75 mivec isn't a race engine, much lower HP per litre.
It's a different mivec system, SOHC and intake only....for marketing purposes to make customers think it's a race engine.

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Re: Are you all seeing an influx of over cammed combinations?

Post by Fireonthemountain » Sat Oct 28, 2017 10:15 pm

stangbuilder wrote:
Fri Oct 27, 2017 7:22 pm
Well as i said im 62 and have had so many hot street cars i really lost count.Many sbc@ bbc.honestly this is my first ford. not that it really matters.For a FYI.This is my first EFI deal.. No shit i will never run a carb on the street again..racing thats another story. This car had a carb on it that was highly tuned Put Efi on it. Its really hard to find anything wrong with Efi

starts better cold@ hot
response is second to none
gas mileage
lap top tune. The tuning is everything most old hot rod guys dreamed about You think about it you can do it.

Downside cost.....
I would say cost and dependability once its not factory EFI. Other that that they can be awfully sweet. I have had EFI since the 90s and had the electronics fail more than once without driving it that many miles. Its not practical for me anymore to have something that unreliable. I am 7 years older than you, so I picked up a "Street Demon" 1904 to replace it. Basic, and should be easy to tune and highly reliable. Should be easily tunable, to midas gas mileage or then back to stun in a few moments with just a change of rods and flapper tension. Almost as easy as a laptop or maybe easier.

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Re: Are you all seeing an influx of over cammed combinations?

Post by Adger Smith » Sun Oct 29, 2017 2:31 am

I've had guys come in the shop wanting a cam that "loafs".
so I sell'em one...
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Re: Are you all seeing an influx of over cammed combinations?

Post by Mark O'Neal » Sun Oct 29, 2017 3:53 am

Rick Finsta wrote:
Fri Oct 27, 2017 7:35 am
Mark O'Neal wrote:
Fri Oct 27, 2017 4:56 am
There is a distinct reason why I chose to run the 3/4 race cam instead of the 1/2 race.
Being asked if you have a 1/2 or 3/4 cam in your car is like being asked to play Freebird when you're on stage. You think it is just an industry joke until it happens to you.

Sure....now. But they were standard engineering terms when I was a kid.......50 years ago.

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Re: Are you all seeing an influx of over cammed combinations?

Post by stealth » Sun Oct 29, 2017 12:40 pm

Mark O'Neal wrote:
Sun Oct 29, 2017 3:53 am
Rick Finsta wrote:
Fri Oct 27, 2017 7:35 am
Mark O'Neal wrote:
Fri Oct 27, 2017 4:56 am
There is a distinct reason why I chose to run the 3/4 race cam instead of the 1/2 race.
Being asked if you have a 1/2 or 3/4 cam in your car is like being asked to play Freebird when you're on stage. You think it is just an industry joke until it happens to you.

Sure....now. But they were standard engineering terms when I was a kid.......50 years ago.
Was a much simpler time.....miss those days
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man.

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Re: Are you all seeing an influx of over cammed combinations?

Post by Orr89rocz » Mon Oct 30, 2017 8:26 am

It seems hard to overcam an auto trans lsx deal. More cam may not make more power but most good tuners can get them to drive fine.

Back in the day guys werent as good on average. Car drivability suffered. But the big cam cars set record et's. Like the old trex cam in a stalled stock ls1. 10 sec cars when gutted.

Ls3 stuff can be overcammed since there heads have large valves and ports that do flow alot. Big window area with relatively mild intake lobe cams. You can make 600+ hp out of stock ls3 heads and intake on a 400+" street ls based block with just a mild low 230's duration hyd roller. Going alot bigger doesnt yield as much return. 5-8 hp with 5-10 more deg duration and a loss of midrange.
A big cam for a cathedral port smaller valve head imo would be giant in a ls3 type large valve head. Stock cube ls1-ls2 can work great with 240 deg cams, really rev up. 240 on a stock cube ls3 is way big

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Re: Are you all seeing an influx of over cammed combinations?

Post by Frankshaft » Mon Oct 30, 2017 9:56 am

Speaking of ls, I have combos figured out for various combos. Recently, 2 buddies, I did a set of 243 heads, and got him my cam. He already had long tube headers, a nice exhaust, ls6 intake, and a yank 3500 converter with 3.23 gears. His buddy wanted me to do the same for him, but he couldn't find a set of 243's for me to port, I lost my source for cheap cores. So anyhow, he bought a set of cnc Prc heads from texas speed, and got a cam from them. It was 12 more at .050, with more lift. He also got a msd atomic intake, has 3.73 rear gears, and a 4200 converter. Same good tuner tuned them both. They both went to the track on same day. The more radical combo, went 11.29 at 121. My combo, went 11.32 at 120. My combo is getting 3.73 rear gears and a fast lsxr intake. These are both 100% stock bottom end 5.7 ls cars. With about 80-90K on them. Drivin to the track. My combo got 26 mpg, the other combo got 19-20. My combo had complete bone stock interior, he let the tranny shift itself, etc. The other car had passenger seat out, rear seats out, skinny front runners, etc. Weighed nearly 200 lbs less. My combo will easily be a 10 second combo when he gears it, and adds the intake and bigger throttle body and runs skinny front runners.

Whats the point, obviously my combo/heads work better. Is the other cam to big? Heads don't work as well? Combo or both? 12 more at .050, more gear, more converter and lighter, its .02 quicker, and 1 mph faster, against a car that has less gear, lower rpm stall, and a smaller cam. It will be a 10 second car this spring. The only way the other car is going 10's is nitrous.

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Re: Are you all seeing an influx of over cammed combinations?

Post by Orr89rocz » Mon Oct 30, 2017 1:35 pm

Theres a chance the gears and intake wont do much for you as well. Depends

Is the other combo shifting correctly for the power band

What did the dyno curves look like?

Do cars weigh the same?

Could be the bigger heads big cam setup on same shortblock is just too big for the compression and cubes. But it should be reving alot higher with its powerband

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Re: Are you all seeing an influx of over cammed combinations?

Post by FC-Pilot » Mon Oct 30, 2017 3:16 pm

Rick Finsta wrote:
Fri Oct 27, 2017 7:35 am
Mark O'Neal wrote:
Fri Oct 27, 2017 4:56 am
There is a distinct reason why I chose to run the 3/4 race cam instead of the 1/2 race.
Being asked if you have a 1/2 or 3/4 cam in your car is like being asked to play Freebird when you're on stage. You think it is just an industry joke until it happens to you.
I just spit my drink all over my computer. LOL Being a gear head and a musician (or as much of a musician as a drummer can be anyway) I loved this post.

I always say "if less is more, just thing how much more "MORE" would be".

Paul
"The latest tests prove exactly what my money tells them to prove".

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Re: Are you all seeing an influx of over cammed combinations?

Post by Frankshaft » Mon Oct 30, 2017 4:08 pm

I have my own line of cams. Monday night special is the mildest cams, Wednesday night special is a bit more "lumpy", then we skip to Friday night special, a bit lumpier yet, then the ultimate is the Saturday night special. Combine that with an Alabama boss hog tq converter matching the day, and you will be unbeatable. I had a Sunday night special, but they didn't sell, so I pulled that from the line up.

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Re: Are you all seeing an influx of over cammed combinations?

Post by bigpoppapreston » Mon Oct 30, 2017 7:15 pm

You guys are killing it with those LS builds and especially with the stock bottom end combinations. Impressive. How much hp are you putting down with those stock shortblocks?
I'm have a modest budget so those builds look great to me. I need to have my build tuned, but i have a 300c with a stock bottom end except for rings, bearings and arp bolts...i have shaved 6.1 ported heads, (363cfm at .650") ported 6.1 intake, 230/238 @.050 595/593 cam, 1 7/8" long tube headers, 25% underdrive pulley, estimated 11.5:1 compression, 55lbs injectors on E85.
I have pictures and a small video clip of it running. Wouldnt doubt it'd make more than 450hp to the ground once all sorted out.
Check it out on my Instagram page @ jerveypreston_fit45
-Poppy

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Re: Are you all seeing an influx of over cammed combinations?

Post by Belgian1979 » Tue Oct 31, 2017 6:09 am

Camming an engine is dependant of what the end goal is and what the type of engine is that you have. If you have a big engine with loads of torque low down that stays 99% of the time in a low rpm range where you need lots of torque, it's easy to cam an engine for that.
If you want a race engine that stays 99% of the time at high rpm, it's easy to cam an engine for that.

The issue comes when you have to make a combination between low and high rpm and on top of that get good fuel economy. That requires ingenuity on the architecture of the engine. In my book VVT is a good solution.

However bean counters in oem's might see this differently for different reasons.

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