408 Cam on the way

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I have brass or had brass shift forks in there and at the time I was doing a lot of drag racing so I felt it a good upgrade to put steel shift forks in...
 
Don't forget to p.m. me when you take it down to the track! I want to be there for sure... I'm positive with your accompanying trick flow heads LOL you'll have the last laugh...
It could be a while so I'm sure we will be hanging out before then man!.
 
I think you're going to be absolutely perfect with your cam. you didn't just buy something off the shelf or something off the internet but you talk to a cam grinder who listen to exactly how you wanted your car to run and he'll likely give you what you want and the word here is for you...
 
Sorry your thread got sorta hijacked Idaho
but you started it mentioning Thumper in the first thread
IMHO you are much better off with your cam than you would be with a thumper cloan
keep us posted with results
all the best
 
Sorry your thread got sorta hijacked Idaho
but you started it mentioning Thumper in the first thread
IMHO you are much better off with your cam than you would be with a thumper cloan
keep us posted with results
all the best

I'm fine with all the comments. Thanks for your feedback.
I have the cam in hand now.
I'd like to get opinions on the install. Four degrees advanced or straight up?
I don't have a timing chain yet so advice on that too.
 
does it not have 4 degrees ground in alredy??
if you are near max recommended compression range I would bit advance it
 
does it not have 4 degrees ground in alredy??
if you are near max recommended compression range I would bit advance it

That's a question I have to ask Ken. He's not available today.
I'll attach the specs. I don't know if that tells you?

6CC5FDF3-B5C1-4646-9508-64391781AD86.jpeg
 
Now that I'm looking at it I'm wondering if I got the wrong cam.
The specs say 1341 when I ordered a 1357. This is a smaller cam.
 
cam card says 108 Lobe centerline angle LCA
104 intake centerline ICL
so it's ground 4 degrees advanced
this is not to say you can stick it in dot to dot and have it come out @104
not on my experience with regrinds unless ken was able to fit the new lobe and keep the keyway in the same place
also Ken gave you the .050 timing
so ask him if he wants you to use the at. 050 tappet lift timing or the measure down both side of the lobe and split the difference to get the nose center 104 method
with asymetrical cams it can make a big difference
also with an asymetrical cam how far down you go to take your measurements makes difference
so 9.8 compression???
what heads do you have flows?
cc'd heads?
gasket cc
piston cc's valve notches
deck clearance?
all checked?

let''''''s ask the forum
Would Idaho be ok with a comp 275 H cam? on a 108

remind me gears weight usage etcnow I'm really sorry we hijacked your thread
but let's try for some answers before calling ken
 
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Now that I'm looking at it I'm wondering if I got the wrong cam.
The specs say 1341 when I ordered a 1357. This is a smaller cam.
I'm sure this is the first question I asked on page one but is it a solid lifter Cam and hydraulic lifter cam a roller cam?
 
Well through research I figured it's got to be a roller hydraulic cam? And yes it looks like you got the wrong one...
 
My mistake for asking that question without the info.

It's going into a 69 Dart resto mod, maybe 3200 lb? Just a tire burning street cruiser, maybe a rare 1/4 mile.
360 Magnum with stroker kit
9.8 static CR
RHS heads by IMM
Air gap intake
750 Holley carb
Dougs 1 5/8 headers
A833 OD (has to be a stick)
4.10 diff
28" rear tire (285/40/18 IIRC)
HDK front susp.

View attachment 1715513649

Yes it's a hydraulic roller.
The machine shop helped with setting it up for a 9.8 SCR. I did the head cc at 62 cc, and he verified. I don't recall the other details.
Thanks for that clarification wyrmrider, I wasn't sure how to determine how it was ground.
I'll be in touch with Ken. Must have been a crazy day at the shop. Maybe Covid 19 related :(
I suppose I could change to anything now.

56CC7BED-E50B-473A-963C-9166587121DC.jpeg
 
Well, fine, but that makes no sense to me. I absolutely love certain engine sounds. The starting cough cough sputter and rough idle of a big radial like the DC3s I used to work on is almost akin to making love. It just tickles a special part of the brain. Anyone who has been to an airshow and heard either a big radial or V12 in a warbird cruise by at close range...


I've been around the modern fighter jets a lot. Awesome in their own way. But the sound of the piston powered warbird is on another level.

Not so sure about the Thumpas but love that P51 Mustang - my uncle flew these with the RAAF in Korea!
 
Yes it's a hydraulic roller.
The machine shop helped with setting it up for a 9.8 SCR. I did the head cc at 62 cc, and he verified. I don't recall the other details.
Thanks for that clarification wyrmrider, I wasn't sure how to determine how it was ground.
I'll be in touch with Ken. Must have been a crazy day at the shop. Maybe Covid 19 related :(
I suppose I could change to anything now.

View attachment 1715521006
Yep it looks like he's going to have to take a touch more off the base circle..
 
I assumed you were waiting for the cam for the pushrods to be ordered..
Yes, I have an adjustable pushrod to be used for that purpose.
I'd like suggestions for a timing chain.
 
Yes, I have an adjustable pushrod to be used for that purpose.
I'd like suggestions for a timing chain.
A quality double roller with several grooves for different timing on the bottom crank sprocket will do
 
That's a question I have to ask Ken. He's not available today.
I'll attach the specs. I don't know if that tells you?

View attachment 1715520920

First off ... I am no cam expert .
But dont the ramps look really slow for a roller cam ? 218 @ .050 and 293 @ .002
I am running one of Kens cams in my 5.9 and have a similar ramp .

Am I looking at this wrong ?
 
First off ... I am no cam expert .
But dont the ramps look really slow for a roller cam ? 218 @ .050 and 293 @ .002
I am running one of Kens cams in my 5.9 and have a similar ramp .

Am I looking at this wrong ?

Comments welcome. I'd like to know.
 
9.8 reacompression you might be more than ok with the current cam
depending on your gearing and rev range you want
you would have a bunch more dynamic compression which is good unless too much
see if ken will let you test it
where's aj when we need him
 
9.8 reacompression you might be more than ok with the current cam
depending on your gearing and rev range you want
you would have a bunch more dynamic compression which is good unless too much
see if ken will let you test it
where's aj when we need him


230/236 @ .050”, 284/290 adc, .515”/.515” lift (1.6:1 rocker), 108 sep vs
218/224 @ .050", .478"/.478" lift (1.6:1 rocker), 108 sep

I'm not advanced in understanding camshaft effects but I'll try.
Am I right thinking the smaller cam will have less idle lope, shine at a lower RPM, broad torque band, drop off HP as RPM rises and have lower peak HP?
I plan to rev limit around 5500, maybe 6000.
I want to have tire roasting torque without clutch dumping but with a .410 gear I think the bigger cam likely has enough to light up th 285/40/18s?
I feel like maybe the smaller one will choke the overall balance of performance, wasting some of what has been put into it.
And as noted, I like a lopey idle.
 
That is a very small cam imo for a 408 with decent compression,the power range would be off idle to about 5k. If that's what you are looking for that's great but it is a big difference from what you had initially planned on. As far as timing chains I have used a bunch of the summit billet chains and the regular summit double rollers with great results, they all had good tension out of the box which can be spotty on allot of the chains out there.
 
Looks like right cam wrong spec sheet, per Ken.
I will verify when degreeing.

Ken suggested 2 degree advance, citing potentially too much cylinder pressure with 4 degrees. I’m not sure about finding a chain/gear set to do that. I may see how the pistons sit in the deck then decide.

9D5F45C2-5267-4FE3-96D4-600DBF392E6C.jpeg
 
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great news
if your compression is near max then straight up
if on the low side then +2 or +4
not including any ground in advance
because the timing slot is almost certainly not in the right place
now did you ask him about measuring down from the top of the lobe and splitting the difference to find the center
if so how far down
or check the .050 timing
do you think both will be the same?
let us know
 
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