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Camshaft RPM range?

General engine tech -- Drag Racing to Circle Track

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88bluestar
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Camshaft RPM range?

Post by 88bluestar » Sat Nov 09, 2019 3:25 pm

I have this cam and wonder both what the rpm range is for it roughly?
Also if you were building an oval track engine for this cam, what would be the ideal head, intake and carb. Rod size etc as well? No titanium parts is the only exception.


COMP CAMS grind #CS 6262/6263 S 108.0 PART # 12-000-47 4/7 SWAP

.020 DURATION 281 285
VALVE TIMING OPEN CLOSE
.050 INT 22 BTDC 50 ABDC
EXH 60 BBDC 16 ATDC
DURATION @ .050 252 INT 256 EXH
LOBE LIFT .361 .367 LOBE SEPERATION 108.0 (SPECS ARE 104.0 INTAKE CENTERLINE)

Geoff2
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Re: Camshaft RPM range?

Post by Geoff2 » Sun Nov 10, 2019 3:35 am

Engine capacity affects rpm range. Smaller engine will rpm higher than a larger engine,with the same cam.

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Re: Camshaft RPM range?

Post by mag2555 » Sun Nov 10, 2019 7:03 am

You can't truly state a given Cams power range until you know what the minimum port diameter is in the full Intake tract.
There are a few on line formulas you can use to do such and they seem to get you to 10% accuracy or less.

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Re: Camshaft RPM range?

Post by pastry_chef » Sun Nov 10, 2019 7:55 am

XTQ solid flat lobes.

Bore and stroke?
Mike R

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Re: Camshaft RPM range?

Post by Dan Timberlake » Sun Nov 10, 2019 10:09 am

This one comes pretty close on comp cams' on line selector.
speed talk cam .PNG
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88bluestar
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Re: Camshaft RPM range?

Post by 88bluestar » Sun Nov 10, 2019 7:22 pm

Let me throw these rules into play and see what you think....
OPTION #2 – 360 Engine
13.10.1 Must be stock appearing. Absolutely no changes are allowed. Must use stock firing order for that make and model (GM to GM, Ford to Ford, etc.). Titanium is not allowed.
13.10.2 Must appear strictly stock for that model and make and in the original mounts. Parts for 400 cubic-inch or larger engines are not allowed. Aftermarket blocks are not allowed. Stroke must match block.
13.10.3 Only stock appearing crankshafts are permitted. Lightweight cranks are not allowed. Undercut, bull- nosed, gun-drilled and/or knife edge crankshafts are not allowed. Lightweight, aluminum and/or fluid dampeners are not allowed. Only flat-top or dished pistons are permitted.
13.10.4 Aluminum or light weight is not allowed.
13.10.5 A minimum one (1) inch plug above the oil level in the side of the oil pan is recommended. If not utilizing
a one (1) inch plug, oil pan may have to be removed at time of inspection.
13.10.6 Absolutely no stroking allowed.
13.10.7 Only stock, unaltered two- or four-barrel low rise cast iron intake manifolds or approved aluminum
intakes are permitted. Approved aluminum intakes are: GM – Edelbrock (#2101 or #2701) or Weiand (#7547 or #7547-1); Ford – Edelbrock (#2121, #2171 or #2665) or Weiand (#7515, #8023 or #7516); Chrysler – Edelbrock (#2176) or Weiand (#7545 or #8022). Porting, polishing and/or port machining is not allowed. Bowtie, aftermarket, SVO and W2, marine, VORTEC or other special production intake manifolds are not allowed.
13.10.8 Cast iron stock production or aftermarket steel stock replacement heads are permitted. Porting and/or polishing is not allowed. GM cars must utilize 76cc heads (approved head numbers are 336, 339, 388, 441, 454, 487, 624, 813, 882, 991 and 993). Aftermarket head numbers are: GM – EQ (Part #CC167ES2 or #CH350I), Dart (Part #10024267 or #10024360) or World Products (Part #043600 or #042670); Ford – World Products (Part #53030; Chrysler – EQ (Part #CH138B) or RHS/Indy (Part #20300 or #20301). Chryslers may utilize OEM steel or aluminum shaft rockers but may not exceed one hundred twenty (120) pounds of valve spring seat pressure and must maintain OEM valve spring dimensions. Heads may be flat milled to reach the 10.5:1 compression rule. Valve size no larger than 2.02 intake and 1.60 exhaust. VORTEC heads are not allowed. Beehive valve springs are not allowed.
13.10.9 Roller cams and lifters are not allowed. Roller rocker arms are permitted.
13.10.10 Must be a maximum 10.5:1 compression.
13.10.11 May be a maximum of 360 cubic inches (368 c.i. for Dodge).
13.10.12 GM five and seven-tenths (5.7) inch or six (6) inch rods are permitted. Must be stock-appearing I-beam
non-polished rod.
13.10.14 Cap screw rods are permitted.
13.10.13 Mushroom lifters are not allowed (stock diameter only). Must match make and model.

13.10.15 Stud girdles are not allowed.
13.10.16 May utilize one (1) Holley 4150 Series four-barrel carburetor (see Article 7.3.3). Carburetors shall be
subject to claim, as outlined in Claiming Procedures (Article 19).
13.10.17 Must utilize a maximum 7400 RPM rev-limiter. Rev Limiter may not be within reach of the driver while in
cockpit and must be easily accessible to officials at any time. Any driver caught altering the rev limiter or ignition system in any way to defeat the rev limiter rule shall receive a 30-day suspension, loss of all track and national points for the night and a $1,000 fine for the first offense. Second offense shall be a one- year suspension, loss of all track and national points for the season and a $2,000 fine.
13.10.18 This engine option is not claimable.
13.11 OPTION #3 – Standard Engine
13.11.1 Must be stock appearing. Absolutely no changes allowed. Must use stock firing order for that make and model (GM to GM, Ford to Ford, etc.).
13.11.2 All engines used in competition must be able to be used in conventional passenger cars without alteration.
13.11.3 Motor mounts may not be removed or altered on engine block. Casting and fittings may not be changed.
13.11.4 Machine work on outside of engine or on front or rear of camshaft is not allowed.
13.11.5 Roller rocker arms are permitted. Roller cams are not allowed. Shaft rocker arms are not allowed.
13.11.6 Aluminum heads and/or blocks are not allowed.
13.11.7 Bowtie or high-rise intakes are not allowed. Only stock, unaltered two- or four-barrel low rise cast iron intake manifolds or the following aluminum intakes are permitted: GM – Edelbrock (#2101, #2701 or #2716) and Weiand (#7547 or #7547-1); Ford – Edelbrock (#2121, #2171 or #2665) and Weiand (#7515, #8023 or #7516); Chrysler – Edelbrock (#2176) or Weiand (#7545). Only unaltered (no porting and/or polishing) aftermarket aluminum intakes are permitted.
13.11.8 Starter must bolt in stock location.
13.11.9 There is no limit on engine cubic inches.
13.11.10 Engines shall be subject to claim, as outlined in Claim Procedures (Article 16). 13.11.11 Mushroom lifters are not allowed (stock diameter only). Must match make and model. 13.11.12 Stud girdles are permitted.
ARTICLE 14: WEIGHT
14.1 The overall weight of the racecar shall be measured after an event with the driver in the cockpit, wearing complete racing apparel. Weight amounts must be posted on both sides of car near the “A” pillar.
14.2 The overall weight of the racecar must be a minimum of two-thousand nine hundred fifty (2,950)
pounds



Or possibly in a B Mod weight is 2350 lbs minimum.



Engine specs are as follows:
i. Maximum of 360 cubic inches with a 1% error. Compression of 10.0 or less with no error.
ii. Stock-type stamped rocker arms or stamped steel, roller tip rockers allowed.
iii. Screw-in rocker amt studs are allowed. 3/8-inch studs only with guide plates. No stud girdles of
any kind,
iv. Poly locks are okay.
v. Must have cast iron two-barrel intake. No acid dipping and no pressure porting. The depth of the
plenum will be measured with a deep side of 3.950 inches maximum and short side of 2.030 inches. We expect to see an unmodified runner to the back of the divider, with ribs that stand up 0.150 inch. Caliper will be used to measure bores and depth. Unaltered marine cast iron two-barrel intake will be allowed with Vortec heads. The Rochester carb may only be used on the OEM two- barrel intake manifold. You can be disqualified or asked to race with a different manifold. The aluminum manifolds allowed are: GM Edelbrock# 2101,2701 or 2716 Weiand# 7547 0r 7547-1 Ford. Edelbrock# 2121, 2171 or 2665 Chrysler. Edelbrock# 2176 Weiand# 7545. These manifolds may use a 1” adapter.
vi. If intake is found to be illegal, driver will lose all prize money for that night and points for that season.
vii. Flat tappet cam shafts only. No roller lifters.
viii. Aluminum water pumps and pulleys are allowed.
ix. Aftermarket power steering pumps are allowed.
x. Must have cast iron cylinder heads, original valve angle and location. Valve springs: 1.250-inch
maximum diameter; .195-inch wire, steel retainers, five full coils.
xi. Any distributor type ignition allowed. No crank trigger or magnetos allowed. No timing retard
control allowed. Must use a rev limiter with a 7,000 RPM chip. Chip must be out of reach of driver. xii. Crank shaft, cam gear and balancer must weigh a minimum of 50 pounds. Must install a 1-inch
pipe plug to inspect crank shaft or remove pan.
xiii. No titanium anywhere.
xiv. Tachometer may be claimed for $300 by promoter and drivers finishing on lead lap.
No tri-y headers

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CamKing
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Re: Camshaft RPM range?

Post by CamKing » Mon Nov 11, 2019 9:26 am

First off, you don't design the engine around the cam, you design the cam to fit the engine, and the application.
Second, since you classes you want to run, have rev-limit rules, you need to figure out what RPM you'll be coming off the corner at, because the rev-limit will keep you from throwing gear at it, if you're not coming off the corner hard enough.
Assuming you build a 350-360ci engine, the cam you gave the specs on, would be OK if you're coming off the corner above 4,500rpm.
If you're coming off the corner much lower then that, you'll need less duration, and probably a tighter LSA(depending on how well you can hook it up).
Mike Jones
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Re: Camshaft RPM range?

Post by Walter R. Malik » Mon Nov 11, 2019 10:07 am

Your first rule under OPTION #2 says "Stock firing order".
http://www.rmcompetition.com
Specialty engine building at its finest.

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Re: Camshaft RPM range?

Post by 88bluestar » Mon Nov 11, 2019 10:30 am

Mike, Can this cam be reground to have less duration?
CamKing wrote:
Mon Nov 11, 2019 9:26 am
First off, you don't design the engine around the cam, you design the cam to fit the engine, and the application.
Second, since you classes you want to run, have rev-limit rules, you need to figure out what RPM you'll be coming off the corner at, because the rev-limit will keep you from throwing gear at it, if you're not coming off the corner hard enough.
Assuming you build a 350-360ci engine, the cam you gave the specs on, would be OK if you're coming off the corner above 4,500rpm.
If you're coming off the corner much lower then that, you'll need less duration, and probably a tighter LSA(depending on how well you can hook it up).

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Re: Camshaft RPM range?

Post by CamKing » Mon Nov 11, 2019 10:38 am

88bluestar wrote:
Mon Nov 11, 2019 10:30 am
Mike, Can this cam be reground to have less duration?
Yes, but if the firing order is illegal, you will need a new cam.
Mike Jones
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jonescams@bellsouth.net
http://www.jonescams.com
Jones Cam Designs' HotPass Vendors Forum: viewforum.php?f=44
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Re: Camshaft RPM range?

Post by Krooser » Mon Nov 11, 2019 11:10 am

The following is an editorial comment not necessarily that of station management...

"God these rules get so darn stupid...."

Now back to our regular programing.
Luxemburg Speedway Hall of Fame Member Class of 2019

88bluestar
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Re: Camshaft RPM range?

Post by 88bluestar » Mon Nov 11, 2019 12:02 pm

I may choose to use it for an engine rule that doesn't have the firing order rule, But likely still have you regrind it Mike, and get your solid lifters.
CamKing wrote:
Mon Nov 11, 2019 10:38 am
88bluestar wrote:
Mon Nov 11, 2019 10:30 am
Mike, Can this cam be reground to have less duration?
Yes, but if the firing order is illegal, you will need a new cam.

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Re: Camshaft RPM range?

Post by CamKing » Mon Nov 11, 2019 12:40 pm

88bluestar wrote:
Mon Nov 11, 2019 12:02 pm
I may choose to use it for an engine rule that doesn't have the firing order rule, But likely still have you regrind it Mike, and get your solid lifters.
CamKing wrote:
Mon Nov 11, 2019 10:38 am
88bluestar wrote:
Mon Nov 11, 2019 10:30 am
Mike, Can this cam be reground to have less duration?
Yes, but if the firing order is illegal, you will need a new cam.
Just let me know when you ship it.
Mike Jones
Jones Cam Designs

Denver, NC
jonescams@bellsouth.net
http://www.jonescams.com
Jones Cam Designs' HotPass Vendors Forum: viewforum.php?f=44
(704)489-2449

88bluestar
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Re: Camshaft RPM range?

Post by 88bluestar » Mon Nov 11, 2019 1:33 pm

Will do so, waiting to see what our local track does as far as rules for 2020 then Ill know for sure.
CamKing wrote:
Mon Nov 11, 2019 12:40 pm
88bluestar wrote:
Mon Nov 11, 2019 12:02 pm
I may choose to use it for an engine rule that doesn't have the firing order rule, But likely still have you regrind it Mike, and get your solid lifters.
CamKing wrote:
Mon Nov 11, 2019 10:38 am

Yes, but if the firing order is illegal, you will need a new cam.
Just let me know when you ship it.

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Re: Camshaft RPM range?

Post by rebelyell » Tue Nov 12, 2019 3:51 pm

Been a while ... 4/7 cam exhaust note sounds different; kinda hard to mask that.

But IIRC, on motors using Big HEI caps, there is a trick to obscure the visually obvious spark plug wire routing cues.

IIRC, those aftermarket "Correct-a-cap" or "Crossfire cap" Intended to simplify wire routing
https://www.summitracing.com/parts/dui- ... gL-qfD_BwE

Those used in concert w/ 4/7 swap cam BUT then route wire like OE ... it'll look like sp wires (and FO) are OE orientation.

You'll still have that 4/7 swap sound though ... and any teardown.

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