408 And A 5-Speed - My Dream Build -

[JDreamR/T]

Just so you have something to compare with. These are my cam specs for my .030 over 360, 10.8 to 1 compression, SRP forged flat tops w/ -5cc valve reliefs. I am running 1.7 rockers for a total of .571/.578 lift (or something real close to that)

Thanks, for sharing your cam card 99dart. Looks like it has a good amount of lift especially if you're running the 1.7s. I'll likely get something close to that lift but with a little more duration. HIPOTEK aka Richard recommended .520"-.550" and a 236 intake duration. I'm using 1.6 rockers.

[99lowdakota]

Its actually better to stay 1.6 rocker ration as the 1.7 has been know to cause valve train turbulence at higher RPM. But it should still run well for you. You may need a rocker girdle later for them.

[99dart]

Its actually better to stay 1.6 rocker ration as the 1.7 has been know to cause valve train turbulence at higher RPM. But it should still run well for you. You may need a rocker girdle later for them.

Hmmm... I ran these on the stock engine with heads/cam. It ran fine then. Since the full engine build, I have a high rpm, very fast, staccato miss. Wondering if what you talk about could be contributing to it. I am pretty sure the springs we went with are too weak in the closed position. They were advertised with a higher closed rate when we were researching. Seat Pressure: 112 lbs @ 1.650
Open Pressure: 336 lbs @ 1.100 Any thoughts, 99lowdakota?

[arro222]

Hmmm... I ran these on the stock engine with heads/cam. It ran fine then. Since the full engine build, I have a high rpm, very fast, staccato miss. Wondering if what you talk about could be contributing to it. I am pretty sure the springs we went with are too weak in the closed position. They were advertised with a higher closed rate when we were researching. Seat Pressure: 112 lbs @ 1.650
Open Pressure: 336 lbs @ 1.100 Any thoughts, 99lowdakota?

Could also be fuel pressure or electrical switch. Weak springs are more likely to create valve float and will cause a "sputtering" that gets worse as rpm's increase. You can hook up a vacuum gauge and see if it holds steady at 2500 rpms and then fluctuates as rpms get higher. If it does, that's weak springs.

[99lowdakota]

Could also be fuel pressure or electrical switch. Weak springs are more likely to create valve float and will cause a "sputtering" that gets worse as rpm's increase. You can hook up a vacuum gauge and see if it holds steady at 2500 rpms and then fluctuates as rpms get higher. If it does, that's weak springs.

What Arro said. and as you increase the open pressure the 1.7s will have more of a load on the stud then a 1.6 ration because of where the fulcrum is located on them.

[JDreamR/T]

Hey guys, so got quite a lot of updates. Where to begin...
Well not much has progressed with the truck itself, but there's been good progress on the motor. I bought a nice camshaft from HiPoTek and got that installed.
1. Since then there's been a LOT of sorting out where the R/T heads are concerned. Been a learning curve for sure measuring for correct rocker geometry and spring pressures. The.100" longer valves work but come a tad bit shy of the 1.80" installed height between 040"-.050" shy. I had my springs tested, they are PAC double springs sold by Hughes and HiPoTek. Closed they are about 150-160lbs and 380-390lbs open.

2. In other findings, it has become apparent now that I may also need longer rocker studs. With longer valves and pushrod combo to correct geometry, the rocker inevitably sits higher up on the stud. Currently I have only about 6 turns on the adjuster nut which is not enough IMO. I'm also a bit concerned with stud flex/fatigue, seeing as the higher fulcrum places a greater leverage on the stud.
Does anyone have any suggestions in this area? Should I consider a stud girdle kit as some insurance? FYI my selected pushrod length is 7.150", I used the 90° to valve stem at half valve lift method for measuring PR length. I determined that length also gave me the most efficient wear pattern albeit the wear is on the outer 1/3rd of valve tip. Valve lift was also closer to advertised cam specs for 1.6 ratio rockers, bit still about .010" shy from max lift.

3. Oil pump install issues: so I vaguely remember this being brought up in other builds. There is a huge interference between the body of the pump and the rear main ARP stud. What is the common solution here? Do I forfeit the stud for a bolt? Or do I try and trim it down and install without the washer?

Thanks guys I know thats a lot haha but its been a while so yeah. Also in other news I setup a dedicated Instagram page for the truck. Follow me if you have an account, my handle there is shaker408rt. Its definitely easier to post photo updates of progress on there.

[99dart]

My son & I discovered that the thick pushrod guide plates were messing up rocker geometry. He was using the same as your pictures on Instagram look. He found a thinner Comp guide plate that corrected our issues. https://www.jegs.com/i/COMP-Cams/249/4825-8/10002/-1 I came home and installed the same on my engine. You will have to clearance the pushrod slots though, we found both sets had variance in the opening that bound the pushrod.

[99dart]

I also found this while looking for the guide plate info. Longer studs. Scroll down for picture & pt number. https://board.moparts.org/ubbthreads...de-plates.html

[JDreamR/T]

I also found this while looking for the guide plate info. Longer studs. Scroll down for picture & pt number. https://board.moparts.org/ubbthreads...de-plates.html

Thanks 99dart for sharing that info.
Finally got around to uploading some pics to share here are a few:


Checking the cam (degree'ing)




Establishing rocker arm geometry, finding optimal PR length




Analyzing PR travel through the PR bores...


A little more clearancing was required...


Assembled rockers with 7.150" PR's

[JDreamR/T]

More pics...

So here is the wear pattern I got, measured width is about .030"


Lapped valve seats...




Assembled Head


Attemped to use +.050" valve locks, to get a full 1.80" installed spring height, however this was the result


And these are the spring pressures that were tested from my machinist. Again these are the Hughes 1129 Double Springs (PAC) that have an advertised 391lb/in spring rate.


Lastly this is the cam I'm running:

(The green sticky note was from my machinist finding a comparable cam to find ideal spring pressures, since no spring recommendations was listed on the cam card)

[JDreamR/T]

http://www.dakotart.com/forum/showth...ght=Main+studs

Thats a link to the same problem I've run into on the ARP main studs interfering with the oil pump body.

From what I see, not sure if cutting down the stud/nut is a smart choice. Looks like too much material needs to be removed. I think I'll have to go with a bolt on that one side.

[98Dak408]

A customer called a few months ago and asked about this. I told him that I had used a bolt for clearance, but to call ARP, as maybe they have come up with something by now. After a few days he got back with me saying that ARP was aware of this problem, and ARP sent him a couple of bolts for the pump main cap, free of charge.

[99lowdakota]

http://www.dakotart.com/forum/showth...ght=Main+studs

Thats a link to the same problem I've run into on the ARP main studs interfering with the oil pump body.

From what I see, not sure if cutting down the stud/nut is a smart choice. Looks like too much material needs to be removed. I think I'll have to go with a bolt on that one side.

DO NOT CUT THE STUD. If you call ARP they will send you a bolt free of charge. I actually called and got them to change the kit like a year ago. And Huges also includes the bolt with there girdle kit now as well. I has always been an issue with the stud kit on these motors

[JDreamR/T]

Thanks gents. Called ARP today and they are sending out low head bolts to correct this. Thanks again for the advice guys.

[JDreamR/T]

Got some engine parts finished in new powder coat the other day!

M1 4bbl



Valve covers I had redone in a gloss black w/ gold metallic

Was thinking of sanding the fins but I think I'm going to keep it as is! In love with this color and compliments the orange block nicely!







What do you guys think, makes for a pretty nice pumpkin eh?

[nitroram33]

[arro222]

Dream: your valve stem witness looks just about perfect to me. Swing looks good. Some people like to see this mark dead center but I always looked at that as a mistake. Valve stems like to "turn" a bit. The area in your pic allows them to do that better with less bind. It is always better to have a push rod slightly longer than shorter so yours are a good length.

Ppl go back and forth with this but for me, that's where I like to see the stem against the rocker tip roller.

[JDreamR/T]

Thanks arro, agreed. From my understanding, having the witness mark centered isn't as crucial to minimizing the overall width of the mark. Less lateral movement of the roller tip the better. Also I wasn't achieving good rocker lift efficiency in using a shorter pushrod, gross valve lift was falling short of the advertised lift of my cam.

I'm actually now on average still approx. .025-.030" shy of total advertised lift. My measurements show .518" Intake, .529" exhaust. I'm chalking it up to the rocker not quite being a true 1.5 ratio Kinda disappointing but not much else I can do. Thought maybe the loss could also be attributed to rocker stud flex, I measured that too and saw .001" deflection at the top of the adjuster.

[JDreamR/T]

Intake: .518"


Exhaust: .529"

[arro222]

PM'd about your old engine.

[blackknight]

Coming along very nicely !

[99dart]

Looking very nice! You wrote 1.5 ratio rocker above, was that a typo? Our stock ratio is 1.6.

[JDreamR/T]

Looking very nice! You wrote 1.5 ratio rocker above, was that a typo? Our stock ratio is 1.6.

Yep that was a typo, I have 1.6 ratio rockers. I managed to clearance out the PR tubes. Happy to say no more pushrod deflection, I have consistent lift measurements for all my valves now! All I have left to button up the engine is to port match the M1.

[blackknight]

Looking very nice! You wrote 1.5 ratio rocker above, was that a typo? Our stock ratio is 1.6.

Pat it is stamped on the rocker 11-1.6

[JDreamR/T]

Sup guys, just wanted to say happy new year, and I am looking forward to firing up the engine very soon! Been working hard on it and have many updates to share which I will get to also. Stay tuned, just gotta get my hands on a base tune from Flyin' Ryan, and figure out the "Cam Sync" sensor calibration thingy.