I’m building a 383 stroker and I’m at a point where I need to choose the cam. I only have an Apple laptop and I don’t want to spend $150 to run a Windows emulator and another $150 to run engine simulation just to pick the cam. Could someone partner with me to run the calculations?

To be clear, I have no interest in “this cam worked for me”. I want help to choose the cam based on the components I already have. Only reply if you have the software, know how to use it, and are willing to help.

I promise I’ll give you credit and sing your praises.

BTW, already tried Comp; never responded, dead end. I trust the people here more than some employee of a vendor.

This is for the Frankenstein 69 project.

 

Are you putting a better flowing plenum, runners and base on the L-98? That is going to determine everything.....
What is your expectation of the cam? Idle quality?
I don't have software.....I have experience.

Jebby

 

Well, Ive got the following:Core: '88 L98 block, diamond bored to 4.030 and deck shaved .005"

crank: SCAT 9-350-3750-6000-L

SCAT 6" forged I-beam rods

Probe 4.030 flat-top forged pistons for stroker, part 12337-030

190cc Street Heads, Straight Plug w/heat riser, 74cc

=> Heads: AFR 190. 74cc chamber, straight plug,
Flow chart:

.200 .300 .400 .500 .550

Int 135 213 253 276 279

Exh 110 158 190 207 211

Matching with a Muncie M20 (‘70 I think) and rear is Dana 44 w/ 3.08 ratio

Intake is an Eddy Performer RPM and planning an Eddie AVS2 800cfm w/ manual choke.
Have Hooker long tube headers (1.65” OD) and dual 3” exhaust all the way back.

Dont plan to race, just street performance, cruising Grand, Sunday driving. Don’t mind a rough idle but don’t want to have to shift at 4500, so probably a mild-to-hot. I intend to set redline at 6400.

Thanks, Jebbysan.

 

That's a pretty basic build that's been done a gazzillion times. A couple hours on You Tube would come up with a ton of real life dyno tests with varying cam comparisons. Nothing too complicated with this build.

Otherwise...if that's not appealing...I suggest you buy the software you like and have at it.


JIM

 

This is my recommendation......
Hydraulic Roller Camshaft & Lifter Kit; 1955 - 1998 Chevy 262-400 2200 to 5800 Howards Cams CL110255-10 | Howards Cams

I used this on a 385ci earlier this year and it pulls like a train.....sounds very nice....not too radical......with an Air Gap and 750hp you would see 460hp and 500 ft/lbs. torque if you set this up at 10.5 to 1......
The mentioned 385 small block used a Dart 180 head that I went through and cleaned up each port on......and it used a Performer EPS intake that I cut the divider down a bit.....Street 750HP.....1 3/4" headers......
We went with a 1.5 rocker on this but on your I would use a 1.6 for .544/.565 lift.......the AFR heads stall a little higher and the port size is bigger......I went with a small port on this to make very high average torque starting off idle.....it is a beast.....700r4 trans.
The AFR heads will be a little peakier......the 6400rpm is spot on.....our 385ci revs to 5800-5900......don't stare at peak power numbers......

I was under the impression you were going to use the TPI runners and EFI.......the Air Gap flows about 5 times more air than that thing so right choice......

Jebby

 

Thanks @Jebbysan Do you think the AVS2 800cfm is too much for this? I’m really interested in the AVS2 line because of the annular flow booster but the choices are 600 or 800. Would that cam push it enough to keep velocity high enough? Also, my headers are 1.65… any concern there?

 

The headers are on the edge......but save the 800 Edelbrock for a truck and use a Holley HP...preferably the 750 Classic HP......the Edelbrock is not properly suited for anything over 400hp, doesn't like vacuum lower than 12 inches on the street and needs a regulator to hold 6psi or it will blow the needles.......
There is a reason why when you see all these engines on a dyno that none of them use an Edelbrock carb......I stopped using them 10 years ago.....just not a good choice for anything that makes power.....and the fact that they came out with a Race carb in the vane of a Holley pretty much says it all.......
I have made Edelbrocks work on different engines....the 66' in the avatar photo had one that I tuned perfectly......but it took a lot to get there.....
At 400+ horsepower you are moving some air.......you need a mixer that is suited to moving that much air........the Classic HP fits that bill......one of the most versatile crabs made.

Jebby

 

But I thought we weren't going to use "personal experience" in any of this stuff...just computers??

There's a few folks here which could help you if you wanted it.....

Jebby is steering you right. Edelbrocks are great low HP street carbs. I just went through one this last week on a mild build. They start instantly and drive well.....but the Holley is the hands-down favorite for power.


JIM

 

Just curios Jebby, why is it you recommend a cam with split duration with good AFR head that have a great intake to exhaust flow ratio? Not disagreeing with it, just want to understand the logic.
What would you think if that cam was was 282/282, 230/230 @ .050 on a 108 LSA?

 

that is exactly what I recommend to people as well. I had a 650AVS on my c3 for years, recently switched to a Holley.
edelbrock beats it in starting easy and simple driving, but the Holley for actual power.

 

Those are advertised cam lobe degrees and the accepted bench mark in engine building is duration @ .050 which is what those numbers are......
Throw all of those calcs away.......they do not take in account the biggest factor of making power which is VE...(volumetric efficiency).......different heads and combos will have dramatically different VE......this is how I roll......getting the number to 100% or better is the goal......I have a fuzzy knowledge of what it takes compression and flow wise to make good VE after doing so many combos.......it makes for a seriously torquey setup that pulls all the way to the top.....massive acceleration.......
You see...racing numbers also requires you to have a perfect gear split and ratio to keep the engine on the boil......torque negates that to a degree....so you can run higher gear ratios and still pull hard.......
I believe in small heads, large-ish cams and smallish carbs on the street.......good 180cc heads flow very well but make kick *** velocity in the port.....a larger cam takes advantage of this while the VE and the high compression ratio makes up the difference in torque.......
The guy who had me build the 385 had the same AFR 195cc Competition heads.....I talked him into a Dart 180cc.......damn thing breaks them loose past 80mph at just about any start speed......that's torque baby......
A member here BKbroiler....has a 383 with Vortec heads on it ( I believe Vortecs are 170cc's) with a nice cam, intake and a worked Q-Jet for deadly consistent 12.1 second 1/4 miles on slicks.....it could go 11's with some work, but he is afraid to lose consistency as he bracket races......the point is that it has a small, good flowing head on it....and it will show you a sliver of air under the front tires on takeoff.....that's torque baby.....
On the street....you want good power with High Average Torque......it will put a smile on your face everytime....they sound good, and you do not have to run them even 6000rpm......

Jebby

 

I would think that is a 280H Magnum...LOL.....
The split isn't that much......4 degrees.....with 1 5/8" headers and full 2.5 exhaust...the added exhaust duration and lift is nothing but helpful.....
I like this cam a lot.....it is one of my favorite street grinds now.....

Jebby

 

LOL, was just going back to delete that message... math is tweaking my head! Thanks for the explanation, I think I understand now! Thanks for your help, Jebbysan!

 

It is, just on a 108 LSA instead of a 110.

 

Since we're looking at past combos.....we had fun building this 400" one for a magazine project. It was a plan to just select parts and bolt them together with no tweaking (which killed me!) using parts from the DART engine packages. We used an all forged bottom end in an SHP block and a set of their as cast 200 cc heads. These were actually their early design..not the newer ones. Definitely not where AFR CNC heads are...but they did work.

We used a tight lash solid roller cam 248/248@.050 on a 109 LSA and lift went over .600" with the 1.6 rockers. There was a LOT of strategy in this came. I spent over an hour with Billy Godbold at Comp going through various lobes basing it on "where" the restriction would be. It wasn't the carbs....it would be the tiny intake. The only way to get more air is more duration. Same on exhaust side..."where" is the restriction? Manifolds? Headers? Mufflers? Which mufflers because they act different. Etc etc. This one uses an "intake" lobe on both intake and exhaust side for the better ramp rates. We could have done it with a hyd roller also..but the owner likes the solid lifter sound.

We tested it with 3 carb/intake setups. Since it was destined to go into a pretty much original '61 283/270 HP car with hubcaps...we first tested it with a heavily ported/welded 283 2x4 intake using WCFB carbs. Tiny intake even after porting it to within an inch of its life. We had to add metal to top of the runners (and then disguise so no one notices) to cover the intake ports in the heads. Then we threw on a Dart dual plane and 750 Holley and then a Weand low rise single plane with the 750 Holley.

It is in the car with a TKO 5 speed and 3.08 rear gears. It runs killer and is easily drivable.

JIM

 

Another one I put together for my best friend is a 388". He found some used as cast Dart 220 cc heads. He didn't want to take the time to port them at the time...so we just put it together. This one is using that same Weiand low rise single plane and Holley 750. We used another solid roller...but this time we knew we'd have 1-3/4" headers and a more aggressive driver. Similar lobes...a hair bigger on a 108 LSA along with 1.6 rockers.

I swear the thing will literally idle away from a red light with a 4 speed and 3.36 gears. I was actually surprised how docile it drives. Yet it will pin you in the seat like crazy.

He only took it to the track once...on BFG street radials and literally off the street with capped pipes, air filter etc... and as you can imagine it spun all the way through 2nd with him peddling it. He crossed the line in 3rd gear...and still ran 12.0's at 116+ MPH. With some traction and some tuning it's a low to mid 11 second car easily. Some gears would really wake it up....in fact he's got 3.70's in it now and it's a rocket. He drives it like this every time he gets behind the wheel...and has been for more than 10 years.

I'm not scared of "BIG" heads on the street. My 555" has heads folks have said are way too big...yet it made 742 lb ft on pump gas and 871 HP. Drives like a baby.

JIM

 

You made that power through manifolds? Tell me more....that is a large cam to have no scavenging......is that an exhaust balance crossover up front on the dyno?
The 388 is impressive too.....with that 220 head.......

We built 555/565's with 345+ cc heads all the time back in the 2000's......they all ran great but that big bore is a whole different ball of wax......you probably spun your N/A combo pretty high too I bet......
I love 565's.....probably my favorite engine of all time......still a short deck, massive torque and ballzonya power......632's and all that are cool.....but all stroke.....

I could put bigger heads on my builds but they are just so much better off idle and you can lug the **** out of them in the wrong gear with a small head......keeps the carb signaled.....and they make just about the same power upstairs.....my school of thought and it works....
The big solids are cool too......but no one wants to lash valves.....I drove a members 1980 406 Auto combo with a Howards Hyd. Roller like your solid and it was sick.......better point where you are going first LOL.....

That WCFB Dual Quad intake is very interesting......one of the worst "performance" intakes ever.......but I imagine the whole package was neat.....500hp in a fairly stock solid axle would be white knuckled LOL.....were any mods done tot he WCFB's?

Fact is.....it is really hard to screw up a well built engine with todays heads and cam grinds......they are all just so good now.......and the learning curve has pretty much reached its end......everything that has been done to improve something has been done to the SBC/BBC.....


Jebby

 

Those numbers were with headers...but it was only down about 20-25 with manifolds. Yep..that's a crossover pipe the C1's used. It IS a rocket and surprises lots of folks. He loved picking on Viper guys from a roll where it had half a chance of hooking up. We used that cam to get some time to get air through that ridiculous intake. I would have taken out more metal but I was scared it was going to crack. But it's held up for years. The carbs were really nothing special. Original ones to the car and the A/F and BSFC was actuallly pretty nice. That 495 HP pull was actually about the first one. I wanted to play with lash etc to make it go over 500, but the owner was insistent that we not do that so folks wouldn't accuse of us of "dyno racing" for the magazine article. The previous engine we built for it was a 383 with some ported double humps using a Crower solid flat tappet I like for those heads. On the chassis dyno it would out do Z06 C5's on TQ and HP up until about 5200-5400...then the manifolds and intake would choke it down. That was with the unported intake. So yep...small heads can be a lot of fun too.

My 540/565 is currently using CNC 365cc heads...previously it had some hand ported ones at 377 cc. And yep..I tend to like RPM...I shift by "feel" around 7600-7850 RPM most of the time according to the data logger. Having the big heads helped hook it up a little better when it was N/A. Doesn't really matter now with the turbo's...it's useless anywhere! LOL

I recently bought back the '82 GT Mustang I had purchased brand new and later sold. It had been sitting for about 18 years in a garage, but before it was parked it ended up with the basic Edelbrock head/cam/intake/carb package. So it's not a big fancy head by any means..and the cam is a mild hyd flat tappet with only 204/214@.050 on a 112 LSA and .448/.472 lift. I swapped the Performer 289 intake for a Performer RPM, and the Edelbrock 600 for my trusty 50 year old Holley 750 DP and then stuck 4.10 gears in the rear to replace the 3.08's which work great with the TKO 5 speed they had installed. Anyway, the thing is a hoot to drive. It will loaf along in 5th gear at 1000 rpm and never buck or surge....smoke the tires from a roll in 1st or 2nd and burn them into 3rd...and pull 6500 RPM in 4th gear any time you want to. It really is a fun combination like you're describing. A better cam would help it a lot and a little grinder work on those heads....but with so few cubes (306) I was able to feel the drop in under 3500 RPM power with just the intake swap. But it wails once it hits 4000 RPM. So little motors are sensitive for sure.

There's multiple ways to do things. I was always impressed with the Boss 351 Fords. Giant heads and a cam much milder than an LT-1....and they made more power and drove like a pussycat. And the LT-1 cam drives well already!

JIM

 

@Jebbysan I ordered that cam, on its way. A follow up question: What about rocker arms? Should i stick with stock 1.5 ratio? Those heads’ flow rate change only two points from .5 to .550 (no change .550-.600) and exhaust changes 4 from .500 to .600. And I’m using flat top pistons, .040 mls head gaskets, and deck was shaved .005. Oh, and the crank is a 3.75 stroke with 6” rods. Any recommendations?

 

depends on what you value for the $$
do you want to spend an extra $200 or so for maybe 15-20hp? Most of that at the top end too.
you said usage was street driving, may not be worth the cost.