nice little roller hydraulic and 750 double pumper.

 

Post the cylinder head manufacturer and head part number, along with the piston manufacturer and part number and I can run a Sim on the motor, trying different cams and different install numbers. What is the piston deck height and who made the head gasket, what part number? I like to run the static compression ratio for myself and will need the following info from you....
engine overbore
piston deck height (crown of piston to block deck with piston at TDC)
piston mfg and part number, need to know crown volume
combustion chamber volume, cyl head mfg and part number so I can find flow numbers to enter on the DynoSim software.
Head gasket mfg and part number

 

Thank you F-Bird! So, you think this cam could be easy enough to get along with on the street? I was wanting something that wouldn't be real boggy on the bottom end and from light to light, but it sounds like it would work. And plus, your combo sounds like a super cool setup!

Techinspector, unfortunately the motor is at my brothers shop right now. And I don't know any more specs off the top of my head other than what I have posted above. (I bought the motor already built). We are planning on tearing it down in a few days and cleaning it all up as it has been sitting in its shipping crate for a few years now gathering dust. So ill see if I can gather more information on it.

But thank you both for the replies and advice, keep it coming!

 

Melling 22404 flat-tappet, solid lifter mechanical camshaft, lash unknown.
CLASS IV. NOT CALIFORNIA COMPLIANT. NOT COMPUTER COMPATIBLE.
POWER RANGE 3700-7300 rpm's
Advertised duration 290/298
0.050" tappet lift duration 258/266
Valve lift 0.538"/0.556"
Intake centerline 99 degrees ATDC
Exhaust centerline 111 degrees BTDC
Lobe Displacement Angle 105 degrees
Intake opens 30 DBTDC
Intake closes 48 DABDC
Exhaust opens 64 DBBDC
Exhaust closes 22 DATDC

 

That power range is what I'm concerned about. Seems pretty high for a street motor.

 

The cam is way too big, it'll make a lot of noise but run slower. Honestly a tight lash solid cam in the 230s range will make that thing pull hard and give better street manners but it won't be as rowdy. Smaller cams can actually make you faster than going way too big, where you are now. You want your torque peak around 4000 and your power peak around 5800 for that stall and gears. Your peak numbers will look smaller but you'll be much quicker as you'll be driving in your power band. With 3.73 gears a 6500 rpm power peak is near useless on the street. On the track it's a different story.

 

That all makes sense to me. Is there a specific cam for this application that you might recommend?

 

lets say your heads flow 280 ish?
110635-10 NA 290 290 237 237 .560 .560 110 106 Hyd. Hyd. 1,2
2400-6400 Rough idle, Street/Strip, strong mid range. 10.0:1 CR, 2500+ stall.
a cam like this would use most of the heads potential
The engine would make power to 6k plus
torque converter would work great as is. 3.73 gears ,,,? I dont know,that depends on what the car is used for? for the drags it would be fine,for x country travel with out over drive not great.
The 750 double pumper is a minimum.

Myself,I would use a bigger solid cam
vic junior intake and
850 CFM Holley double pumper,,,

this car needs a big exhaust system

 

That cam sounds like a good one. Maybe matched with a RPM air gap and a 750-800 DP? Just exploring options here, as I mentioned before I'm a straight beginner to the hotrod world. Thanks again gentlemen for the help!

 

If you use a Holley double pumper? I would use the 750 or the 850,Ive never had as good performance from the 800,and I do not know why..
The 750 will easily support 500 plus HP.The 850 will easily support close to 600 HP,so it depends on final parts choices and finished combination.
The heads hold the key to this mystery

 

I wish I knew more about the heads or had them handy to see what they really are. 200cc with 64 chambers is all I know at the moment!:nono:

 

That's a little big of a cam IMO, it's a hyd roller, if it was a solid it'd be about right though. For a hyd roller I'd go high 220s duration, again it'll move the power down to where you'll use it.

It's not about peak, it's about max power where you drive.

 

mild solid roller



I would use 240 duration and .585 lift if I used a solid roller.
This is a very mild cam.
My "street cam" is 256/264@ .050 in a bigger engine.It makes peak power at 6.500 rpm and of idle power is great

 

Maybe Richard can do a sim?I would like to see the difference between your cam choice(AP) and mine.
or Richard? maybe set me up with a link for a sim so we dont use up your time so much?

 

WOW! look at that torque at 3k?slightly more HP than torque. If that doesn't melt tires and drive well?????
Thanks Richard,,,

 

OOps, sorry, got the hp and tq mislabeled. Should read RPM/HP/TQ left to right. I went back and fixed it.

 

I don't put much stock in air gap intake manifolds. Just seems like more snake oil to me, plus I want the motor to come up to operating temp as fast as it can.

 

Just what I needed to know:thumbup:. So this cam, RPM performer, and a 750 double pumper sounds like a great street combo to me. And I can imagine it would be much more street friendly than the current cam setup by far.

I also noticed pretty much everyone recommending a Holley carb to me. Just curious the reasoning everyone recommends these over a Edelbrock?

 

If you buy a carb from the carb shop,Pat will have the carb almost perfect out of the box.Or other reputable carb shop. The double pumper is a great performance carb that is easy to work on.Terrible mileage though.The quadrajet is great too,but maybe a little small,and more difficult to tune

 

Can you simulate that with a cam with maybe about 6-8 degrees less duration on the intake? I think you'll find the power in your driving range goes up substantially, few people buzz a sbc above 5000 rpm under normal circumstances on the street. With 4.56 gears that power band looks more attractive but 3.73 gears are not that steep.

On a car that sees regular track duty that would be a great combo, but I don't see it being useful on the street. I've built a few high winding engines and they're more of a pain in the *** than anything after the first few months.

 

I agree with you, it's just like everything else that gets done to the max. It gets old in just a little while and you wish you had built a more tractable motor.

What I consider a really good street motor is one that produces at least 400 ft/lbs of torque at 2000 rpm's. So let's leave everything else the same as above and just change out the cam to a more sedate grind that will achieve the torque figure that I like. We'll use another Howards juice roller, but with less duration, part number 111145-10......
http://www.howardscams.com/component/jdownloads/finish/3/2?Itemid=0
We'll stab the cam in 4 degrees retarded on these numbers....IO (-0.5), IC (39.5), EO (42.5), EC (2.5)
The OP likes a little rump-rump and this cam should rumble a little.....

RPM...HP...TQ
2000...164...430
2500...208...438
3000...267...467
3500...330...496
4000...389...511
4500...435...508
5000...476...500
5500...490...467
6000...476...417

Max volumetric efficiency 95.0% @5000
Max BMEP 201.5 lbs @4000
This cam produces in excess of 450 ft/lbs of torque from 2700 rpm's to 5700 rpm's!!!!!!

 

Great info, many thanks! I don't know a thing about q-jets but I will definitely take a look at them.

 

OK, I'm an equal-opportunity kind of guy, let's build it.....

Cam Spec Card :: Lunati Power

Cam made max power installed retarded 4 degrees on these numbers.....
IO (13.5)
IC (49.5)
EO (57.5)
EC (13.5)

RPM...HP...TQ
2000...146...384
2500...193...405
3000...246...431
3500...311...466
4000...378...496
4500...442...516
5000...503...530
5500...534...510
6000...552...483
6500...548...443

Max volumetric efficiency 104.1% @5000 (Best cam tested for efficiency)
Max BMEP 208.3 lbs @5000 (Best cam tested for cylinder packing)

Edelbrock dual-quad RPM intake mounting two 500's makes 565 hp @6000 and 537 ft/lbs of torque @5000.

 

Both of those cams look good. I'm considering going with the first one, incase I decide to upgrade to some steeper gears in the future. And it still looks like it would have plenty of torque for cruising around on the street with this 383 the way I am setup now, right? I have just about 100% ruled out running the big solid cam that is in it now, I think it would just be way too much for my use.

 

Unless you plan on cruising around at 5,000+ rpm on the street, OR you're going to spend a lot of time on the track, I can't find a single reason to no use the smaller one. What do you mean by steeper gears? 6.14?

The bigger cam has less power until about 4500 rpm, and at 3,000 rpm (which is where you'll be at most of the time with those 3.73 gears) you give up 50ftlb! 50ftlb is HUGE.

You can get whatever cam you like, but realize that bigger cams will actually make you SLOWER on the street.

On the track where you shift at 6,000+ RPM its an entirely different scenario.

Take it from someone who has BTDT, you want the power where you drive, not off in some space on your tach that the needle will never see.

 

Just for grins, let's run the small Howards hydraulic roller cam with the Edelbrock RPM 2-4bbl intake and two 500's and see what happens.....
Cam is installed on these 0.050" numbers....
IO (-0.5)
IC (39.5)
EO (42.5)
EC (-1.5)

RPM...HP...TQ
2000...168...442
2500...217...457
3000...278...486
3500...339...509
4000...400...525
4500...447...522
5000...493...517
5500...505...482
6000...495...433

Peak volumetric efficiency 96.5% @5000
Peak BMEP 206.4 lbs @4000

There's your daily driver motor, with enough torque to tear street tires off the wheels for a good eighth mile.
A guy could add ~20 hp to this combination with a good set of roller rockers. Not those fosdick sliding ball trunnion pieces of crap from Comp, but real roller rockers with a roller trunnion and roller tip. Scorpion is a good brand. Good price, good quality. Harland Sharp is maybe the top of the heap. Do not succomb to the offshore allure of Chinese rockers.

 

Just for grins, let's run the small Howards hydraulic roller cam with the Edelbrock RPM 2-4bbl intake and two 500's and see what happens.....
Cam is installed on these 0.050" numbers....
IO (-0.5)
IC (39.5)
EO (42.5)
EC (-1.5)

RPM...HP...TQ
2000...168...442
2500...217...457
3000...278...486
3500...339...509
4000...400...525
4500...447...522
5000...493...517
5500...505...482
6000...495...433

Peak volumetric efficiency 96.5% @5000
Peak BMEP 206.4 lbs @4000

There's your daily driver motor, with enough torque to tear the tires off the wheels.

Switch that to an EFI ram style injection system and you're really cooking- unfortunately their not a cheap set up. Properly tuned I could see 17-19 mpg's though. That would make a nice cruiser, fill up only once for a nice Saturday day trip to the country or the shore (depending on your location).

 

Ok, so y'all have me sold on that smaller Howards cam. My question is, it looks great with either the dual 500 setup and the 750 DP. Would it be worth it for a beginner like me to go with the dual setup for a little more power? I do have knowledgable friends and family that could help me if I get stumped, but I don't want to get in too far over my head if they are going to be harder to tune. Although they sure do look cool as well!:thumbup:

 

Looks cool, sounds cool. Have no fear. Between yourself, family, friends and the engineers at Edelbrock, you'll have no problems tuning the combo. Here's the Owner's Manual for Performer and AVS carbs from Edelbrock so you can get a head start in understanding how these carbs work.....
http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf
Make certain that you use the high-rise RPM manifold, not a low-rise model that'll cost a minimum of 50 horsepower from the Sim results shown in this thread.

 

TI you put too much effort into your posts, if I didn't know any better I'd think you're getting paid for them! I'm sure you've done a hell of a lot of good for a lot of board members.

 

Well, I'm retired and every once in a while, I have the time that's required to do it properly. This has been a very good thread and I thank you for your kind words.

It makes me feel good to be able to pass on valid, useable information to those who might not know where to look for it.

 

Also, should this combo be OK on pump gas? Or would I need to get the CR down a little? 90 octane is the normal "Premium" in my area, although I'm always on the lookout for better gas. Elevation is 3200'.

 

If you could drop the SCR half a point to 10.0:1, how would you do it?
If you left it at 10.5:1 and it knocked on bad fuel, would you add a water/alcohol injection unit to stop detonation?

 

make sure you do some math before you buy the parts:
The dyno sim difference between the cam I chose and the cam AP72 chose made different amounts of power at different RPMs,,,but,,,
SAME COSTS,,,
you decide how the engine should perform and when it should do it,,,
with the bigger cam and 3k TC,how long do you think the more powerful engine will take to rev past 4k?You will need a rev limiter,,,

the other combo with 2 carbs,,,needs 2 carbs and a more expensive manifold.
You can also consider a bigger cam than I said or a smaller cam than what AP72 said. either way 500 ish HP is in your future.
It will be a lot of fun to drive

 

I really need to know the answers to the questions I asked you in post #4. All of what we have done has been fun, but it is not necessarily carved in stone. The very first thing I need to know is the actual static compression ratio and to figure it for myself, I need the info asked for. If it is indeed 10.5:1 and all you have is 90 octane fuel, we may need to use a little hotter cam timing, closing the intake valve later and relieving some of the cylinder pressure to prevent detonation on pump gas.

 

10-4. I'll get that info ASAP!

 

Ok, so a little update. I went over to my brothers shop this afternoon and we started to pull apart the engine and clean some stuff up. Come to find out, some of the info I got from the shop that built the engine was wrong. The heads are PC3002 which in my quick search shows a Procomp 190cc/64cc. Doesn't look like they are too highly thought of.

The cam was not what I was told either. It's a solid Isky 547-B #201549. Which evidently is a oval track cam. But it's obviously not what I'm looking for. Roller rockers are blue in color with nothing stamped on them whatsoever.

All I could see of the pistons from the underside of the engine read SRP 40. H beam rods read 8551 S.

Haven't yet gathered any more info to figure the compression ratio as Techinspector has requested. So strictly parts wise, any idea what I'm working with here?

 

That cam is a little too big for your application, and the heads are okay provided they have been checked for machine work and have the bowls and guides cleaned up. You're not sitting as bad as you may think, still need a cam and you probably need some sort of head work.

 

Well that's good to hear. I was worried I had some junk heads after seeing a few people talk about them on the web. Do you think I would still be able to utilize a cam such as the 111145-10 that you initially suggested even though the heads are not what we originally thought they were?

 

There are a lot of other heads out there too, some not as spendy.

If your heads check out fine though I don't see any reason to not use them. Its not that expensive to have them checked, and if they're good then I would just run em, preferably with port work but even if you don't get the work done. No sense in replacing good heads unless you're after every last pony.

Just changing that cam out to something more appropriate is going to make a huge difference in the power you'll feel on the street.