Hello fellow y blockers.  After lurking through some of the posts I finally decided to join the forum.

I have a few cam questions for an upcoming build that I'd like to have some help on gathering alternate resorces, & feedback on some of your previous experiences.

First, here is what I have:

 63 F100 Stake bed that has a 292 mated to a cruise O that I rebult around 12 years ago. The goods inside her are:  .060 with standard rebuild pistons, etc.  Isky e-4, cite heads homebrew port & pollish, with 1.78 intakes, 9425 intake, home made 4 into one mid length headers, 65 reman Autolite 4100 1.08 with a (my specialty) ported secondary venturi & throttle shafts slimmed. 

I last year added 1.6:1 rocker assemblies from Rocker arm specialists that are fabulous!  It actually sounds more like it has an aftermarket cam now, not to mention the nice torque gain with my .438 total valve lift with the E-4 isky & lash being considered.

I should probably leave it alone, but as many of you probably feel, why the heck not define it to what you really want? Right?

I should also mention that after the dana 44 recently had bearing issues I accidentally found a dana 60-2 from a 64 f100.  The difference for those of you who weren't aware of the 60-2 like I previously was is it is a dana 60 that is not a full floater, with 5 on 5 studs & identical brakes to that of a dana 44.  In doing this swap I went from 3.73's that were in the old dana 44, to 4:10 limited slip in my big hunk of indistructible dana 60-2. 

My plans are to do the t-5 swap asap, as freeway driving here in Denver leaves me winding up to around 3800, 4000 to keep with traffic. 

Now for the cam talk:

I have ECZ-G's that I plan on have Mummert do his street port with 1.94, 1.60's.  I am also considering biting the bullet & re-rebuilding the whole thing & getting the dome pistons he has to up the compression to allow me to use a more aggressive cam.  I want to go fast & want it to sound mean @ the cruise nights!

I have considered all of the other Isky offerings, but am indiferent to the low lift figures.  I Like the lift figures of some of the Erson offerings, but have one grind in particular that I want to have custom ground by them.  It is their TQ 30.

The specs are: TQ 30: Advertised, or lash Duration 280, Duration @ .050 230, lobe Lift .310, Theoretic valve lift with 1.60:1 rockers .496, valve lift considering lash .476.

When I talked with Erson, the guy was unfamiliar with y blocks. (suprise surprise)  He did however say for that kind of duration in a 5k or so truck that I should have a min. of 10:1 compression to get the cylinder pressures up to make it work.  He said if I sent him flow figures for the heads, including static compression estimates that he could further help to see if this grind would work. 

 Has anyone ever tried a cam like this?  What combo of components worked or didn't?  Has anyone ever tried a 230° Duration cam@ .050 in a truck?  

Any help would be appreciated.  Sorry for the long post..

63 Red Stake 

Welcome to the site!  Always great to have new members coming on board.

 

Likely the greatest concern with using popup pistons is ending up with a compression ratio that will not tolerate pump fuel.  Because the camshaft is a player with this, there is not a set in stone rule for the static compression ratio in regards to octane fuel requirements as the dynamic compression ratio would over-ride this.  Generally, I like to keep the dynamic compression ratio at 8.5:1 or less for a street engine so the engine will at least tolerate 92-93 octane pump fuel with an optimal ignition curve.

 

The other concern would be with your proposed camshaft selection being used in conjunction with the stock converter.  Manifold vacuum would be reduced just enough that the engine would struggle to idle in gear while maintaining a neutral idle that was not excessively high.  Part of this can be overcome by advancing the camshaft and/or increasing the valve lash setting.  Of course, any kind of increased stall in the converter would give more latitude in this area.

 

Some rudimentary math on your existing combination and some assumptions towards your deck clearance (0.000”) and combustion chamber cc’s (77), I calculate an 8.2:1 static compression ratio for your existing combination.  With the E-4 camshaft installed 4° advanced and the valves set at 0.018” lash, the dynamic compression ratio is 6.9:1 which will allow the engine to run safely on 87 (or less) octane fuel.  If the camshaft was installed straight up (108° intake lobe centerline), then the engine is even more low octane fuel tolerant but cranking compression will be reduced and so will be the low end torque.

 

Throwing this same math at your new proposed combination with popup pistons (10cc dome), G heads that are unmilled at 69cc’s, and the TQ-30 camshaft installed at 4° advanced (assuming the camshaft is ground on 110° lobe centers), I get an intake valve that closes at 66° ABDC which equates to a dynamic compression ratio of 7.9:1 which is in theory mid grade fuel tolerant and workable for your combination.

 

Hope this helps and isn’t too cloudy.

Lorena, Texas (South of Waco)

"When I talked with Erson, the guy was unfamiliar with y blocks. (suprise surprise)  He did however say for that kind of duration in a 5k or so truck that I should have a min. of 10:1 compression to get the cylinder pressures up to make it work.  He said if I sent him flow figures for the heads, including static compression estimates that he could further help to see if this grind would work."

Your plans sound like a lot of extra expense for a 5k truck (or car).  Dont get me wrong because 5000 rpm is fine for me too.  If you arent careful you will build a nice motor for the tracks, that will be a pain in the ass on the streets.

Likely your quench now is a lot more than the 0.00 of Ted's assumption for the static and dynamic compression calculation, meaning even less on the compression stats.  Think what your motor might be capable of if it has the static compression called for by the E-4 of 9.5:1? 

The short block I just completed has an E-4, with static compression of VERY close to 9:1, and dynamic of 8.1:1.  It should  run great within the parameters of my driving habits and needs, and the cam ceiling of 5k.

   

Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor.

Thanks Ted, thanks 46. That does help.  I do think I want to keep the rpms as simple as possible.  I think I am really after a mean Idle, & a couple hundread rpm on both sides.

I know for sure the block was never decked.  So I am sure my Dynamic figures are low.  I am swapping to a t-5 mustang tranny, so that should take care of converter issues.

My E-4 is intalled Straight up, & also since I built this thing while in High School, used the stock silent chain that came with the kit.. Who knows how far behind the cam is!  I probably don't have 20k on this engine, so I would be happy to swap the heads, & put a cam in that allows more of a street rod sound, without altering the current 5k too much & be pleased as punch!

I have been teasing the Idea of applying the dramatic imballances of the dual profile "Thumper" Cams that comp makes.   One possible problem here is that I know they are retro fit roller cams, so I know ramp angles are not remotely compatable.

But lets just say that I took the Erson Tq30M, or even the Fiflow IIM, & merged it with something like My E4.  Could it work??  It looks to me like the exhaust duration will be that of the larger cam. But the exhaust lift would be slightly less than that of a typicall cam lobe with that same duration.  Then it appears as though the intake would be alot milder duration, with a slightly taller lift..  The "Thumper" cams are also ground on 107 lc.  The rpm bands are mild when you consider the idle sounds they produce.

The combo I thought would be great: An Erson Tq20 & Tq 30 combo:

Intake:.220@.050  Lift of .544(1.6 rockers)

EXhaust: .242@ .050  Lift of .496(1.6 rockers)                

In therory, if the valve train doesn't hand gernade, the rpm range should be around 2300-5800.  Quite streetable, & should be tolerant of mid grade fuel.  The Idle should be nice & rough!  Am I Crazy?  Or could a cam be ground to produce the best of both worlds for our Y blocks?  I Personally don't think I will be reving my engine 6k, so don't want to have to build an engine that tollerates that in order to get the sound. I could almost live with what I have now if it sounded the way it does on a cold day, cold start!

According to Mummert, anything over .500 lift with the big valve heads will require notching the block for valve clearance and anything over .480 would require piston notching. I think that he based this on using stock rockers, so with the 1.6 rockers it would be compounded. Sounds like a lot of machine work would be required.

Glen Henderson



Freedom is not Free

Letohatchee, AL

Verry true... I may have to pull the whole thing apart to go much bigger on cam than what I have now.  Esp. with the 1.94/1.60 combo of Mummert's.

For those interested,  these are the specs I found that I would like to see if can be made to work for my Y-block.  I'm going to talk with comp & see what they say... Any thoughts those of you who have tried dual patterns??

THUMPR™ for Small Block Ford Windsor

APPLICATIONCAMSHAFTS

VALVE SETTING

RPM OPERATING RANGE

CAMSHAFT PART NUMBER

CAM GRIND NUMBER

DURATION

VALVE LIFT @ 1.5:1

LOBE SEP. ANGLE

ADV.

@ .050”

IN.

EX.

IN.

EX.

IN.

EX.

IN.

EX.

HYDRAULIC ROLLER High performance street, stock converter ok, best with 2000+ converter and gears, choppy idle

Hyd

Hyd

1900-5600

35-600-8

283THR7

283

303

227

241

.531

.515

107°

*Notes: 1) Fits all Small Block Ford Windsor 1962-1995 that DID NOT come from the factory with a hydraulic roller camshaft 2) 5.0/351W firing order: 1-3-7-2-6-5-4-8 3) Requires 31-1000 retrofit kit and OE style hydraulic roller lifters

Ok, so I realize I might be the only one participating in this topic with myself & me, but here is what I found:

The Guy @ Comp said he could grind this for me, & it would be as close to a thumpr as he could get.  No lifters, just cam.  The guy means buisiness when he "cuts & pastes", so I highlighted stuff to make the partial words make more sense.

            SPEC CARD
PART #: 37-000-5       ENGINE:  FY   FORD 292-312 Y BLOCK SPECIAL CAM
RINDING INSTRUCTIONS 1
""         ""       2
""         ""       3
GRIND #: FY 6017 /6068  S 107.0
SPC INST 1:
SPC INST 2:
J. DIAM: STD       INT     EXH
ALVE ADJUSTMENT   .016    .016
ROSS VALVE LIFT   .500    .513
URATION @    .015
    TAPPET LIFT   270    276
ALVE TIMING     OPEN   CLOSE
@ .050    INT    10     34
           EXH    51      7
PECS FOR CAM INST. @ 102.0 CENTERLINE
                    INT     EXH
URATION @  .050    224.00   239.00
      LOBE LIFT     .313    .321
LOBE SEPARATION 107.0    FIRING ORDER  STD
OCKER ARM RATIO     1.60   1.60  REQ SHIP DATE          (MMDDCCYY)

Any of the experienced guys, feel free to jump right in... I could be hitting page two by myself!!!, or with I If necessary!

Kevin

Non-symetrical or dual pattern camshafts are used when there is a large disparity in the ratio of intake to exhaust port air flows.  If the intake port is too large or the exhaust flow is inadequate, you’ll find a larger exhaust duration than what is being used for the intake.  It’s actually more complex than this but this is the simple explanation.  For the most part, the Y-Blocks are content with symetrical grinds where the intake and exhaust durations on the camshaft are the same.  In my own case where the exhaust is extremely efficient and scavenges very well, then the exhaust duration is actually smaller than the intake.  If just wanting a rumpy idle, then just reducing the camshafts lobe centerline will accomplish this.  The 107° lobe centers you’re talking about will give you that desired rumpy idle without having to resort to an abnormal increase in exhaust lobe duration.

Lorena, Texas (South of Waco)

According to comp, the sound charactarists for their Thunmpr series are largely due to the long duration on the exhaust side carring the overlap sound on the exhaust side... I know simply taking a mild cam & having it ground on 107 would cause the reveberation, but what real harm would overscavenging the exhaust do to the power band? Lay it on me guys, I know some of you have tried stuff that didn't work.  I thought that's what this forum is for.  For us younger guys who didn't have the opportunity to grow up with these cars.

Kevin