Mild Pinto rpm @ max power?

Hi, can anyone have a guess what the RPM would be at maximum power, 2.0 pinto with crow mild street cam? Standard 2.0 is 70kW @ 5200rpm. Thanks
 
(26874) FORD 2000 OHC Mild Street Cam$247.50Add to Cart

Have that cam in the RS2000 on dual 40 idfs with 34 chokes, H&H electronic dizzy, 10.5:1 static compression, Genie bigbore extractors with 2 1/4 exhaust. Pulls from idle, ramps up from 3.5k peaks at 6k, hits wall at 6.5k - though that is partially due to the limits of the carbs. 
 
http://youtu.be/w0E7-Wl4uU4
 
Built this engine in 1997 for reliability rather than outright perfromance, not a rocket ship but is quite streetable. Will be soon replacing with more agressive Piper cam.

Cam's already installed. I wanted the rpm figure for this calculator. I have been able to use this to find out what size rear tyres will replicate a 3.77 diif, so I can test with tyres before swapping diff gears. 175/65/15 with a 4.1 diff will replicate a 3.77 with my 195/45/15 tyres
http://www.locost7.info/gearcalc.php

 

Wozzah
If you take note of the .050" specs of the Crow grinds (any of the Crow Pinto items, even their so called big ones) compared to other brands the figure is small.  The opening and closing ramps a simply too subtle.   
Cheers
Woz

I'm hearing you - it not an optimal power or torque grind for the Pinto engine, but there was method in my madness with the soft opening ramp angle and limited lift key features figuring in the selection of that asymmetric grind cam at the time - my aim was optimising durability and efficiency running 10.5:1 static, mild reworked head, modified 32/36 Weber and small primary headers with 2" exhaust in what was a daily driver. At that time options were somewhat limited, previous Ivan Tighe cam had great power range but was a little too aggressive with bearing, lifter and valve wear; could not find a reliable recommendation for any of the Wade grinds and the Piper/Kent/etc range were stupidly expensive at 30p to the AU$ back in the dim dark 90s.
 
That being said, I am pulling the engine soon to give it the scheduled 15 year freshen up and to maintain a modicum of durability I will be fitting a Piper 285 grind while reconfiguring the engine to better suit its current occasional 'weekend entertainer' duties.
 
In my opinion the 26874 cam is far from hopeless as long as it is matched to complimentary engine preparation and the view is towards improved performance with durability rather than just outright performance.
 
edit:spelling

In my own experience I have found that lsa and intake centreline plays a bigger role then a lot of people realise.

Jimmyd what is your cranking psi? I would guess it would be south of 170psi even with the comp of 10.5.

I would consider 170psi the rough limit of 91 octane. 98 you should be able to go up to 180psi comfortably and 190psi with a good tune.

From what I have experienced cutting a wide lsa ends up being a double edged sword. The grinders cut them straight up or only 2 deg advanced. Not only does the wide lsa drop your cranking comp the "retarded" intake position compounds it making the motor feel lazier than it should.

This combination then means its mandatory to raise your comp to compensate for what the cam is bleeding off. Anything more than 110 I consider a "turbo" grind due to the fact you want to add more psi through boost pressure. Advancing a wide lsa cam brings the intake back into a better position, I try to keep it somewhere between 108-104.

Noono

Very informative info gents, so I would like to further tap your knowledge:

What cam/specs would you recommend for hillclimbs with a Pinto using only 6000 rpm max?

I limit to 6000 to give longevity with cast pistons & standard rods.
Twin 40mm dcoe's, basic Vizard head porting, looking at 10:1 CR or a touch more.

What about the Kent FR30 ? (1000-6000 rpm, high torque, 260 deg duration, 110 deg lsa, about 12mm valve lift).
This camshaft never gets mentioned. Or would FR32 be better, even though only using 6000 rpm.

Cheers, Gregg

 
I would concur with Woz's formula and Spigots further comments above for this application to which end perhaps Woz can recommend an appropriate source for the cam.
 
In the mean time have you considered Piper OHCBP270, should fall in between the two extreames you mentioned?
 
Part No. Power Band Dur. In Dur. Ex V Lift In V Lift Ex Timing Lobe sep
FR30          1000-6000  260 260   0.481" 0.468" 20/60,60/20 110
FR32           2500-7000 272 285   0.434" 0.459" 31/61 79/26 111
OHCBP270 2000-6500 268 268   0.430" 0.430" 23/65,65/23  111
 
In my opinion I believe ultimately it needs to come down to your refered driving style - do you like to 'grunt' it out of the corners at lower revs (FR30) or do you feel more in control pulling down a gear and push out of the corner at higher rpm (FR32) or somewhere in between (OHCBP270)?
 
For reference the cast ACL hypereutectic pistons on std rods have proven to be quite durable for my application, doing a terrific job over the last 16 years and still going strong. The first four running rejetted stock carb, small bore headers, 2" exhaust, first stage Vizard head mods and used as a daily driver with regular 4,000klm + road trips thrown in, next eight years living under a car cover in the garage, last four years sprited weekend driving with dual 40 idfs, Genie large bore extractors and 2 1/4 exhaust; all up over 80,000klms travelled on an unopened engine with just routine maintenance. During that time I have used a max continuous rpm limit of 6,000k though have been known to hold 6,500rpm in the gears as required.
 
PS. suprised myself when I just sat down and worked out how many ks she has done on that engine, back of my mind I was always thinking only 20-25k
edit: formatting

Thanks James & spigot,
The full story is:
 
Club rego, so will be driven in city occasionally as well as club level motorsport.
Twin 40mm dcoe webers, 4-2-1 headers, 2.25" exhaust.
Pinto block bored 1mm o/s, decked 0.25mm, standard crank & rods, Hepolite flat top cast pistons which come to 0.3mm below block deck.
Current head decked 2.3mm, Grp1 valves, basic Vizard porting, Waggot cam In 43/80, Ex 80/43, duration 303, lsa 108.5, lift 11.2mm.
The theoretical c/r is 10.8 : 1 which I've read is a little high for cast pistons.
 
It's a dog at low rpm, which I think is due to the large duration & valve overlap.
I have picked up a good untouched head, so I thought would get built with a different camshaft & about 10:1 c/r.
With the current block/piston setup, I would only need to shave the head 1mm max.
 
I liked the look of the Kent FR30 because of 260 duration & 12mm lift. I guess it's great around town, but may have peak power
too low for motorsport.
James, the Piper 270 looks like it could be a good option. Also the Kent website figures for the FR32 are
In 34/71, Ex 68/32, Duration 285/280, Lift 11.6/11.2mm, Lsa 108.
Spigot, the websites don't give 0.050" durations, but I guess only an email away. What does std hc bottom end mean?
 
Cheers, Gregg