I'm sharing a email I sent to Tim for a camshaft recommendation. Haven't heard back yet., but I figured since I have chimed in so much on other peoples builds, I should give you guys a chance to pic apart mine. Flame underwear on.

"I'm writing you to get help on camshaft selection for my new 408 Ford build. I've pretty much come down to three different camshafts. The comp cams 270H [K32-224-4], the 270S [K32-237-4], OR the ThumpR [K32-600-5]. I'm really wanting to run the ThumpR, but I'm worried about vacuum in a 78 Bronco. I’m sure both of the 270 duration cams will give me much better vacuum, but I have no problem throwing a vacuum canister on if needed. Out of the two 270 dur cams, I'm leaning towards the 270S, but I just can't pull the trigger yet. I keep watching the video in the thread "intake shoot out", it's in the 335 engine forum https://www.ford-trucks.com/forums/1...shoot-out.html , and 470+Hp and 500+ftlb from a Big ***** ThumpR camshaft just gets me thinking. With our engine builds being so similar, maybe the tamer ThumpR would be just bad *** in my Bronco. But it comes down to vacuum. I figure I need 10" or so of vacuum to make it all work. The camshaft is the last bit I need so I can get a properly sized converter.
Thank you for your time.

P.S. Of course if you have a special flat tappet grind I can get from you, that’s better, I would be interested in that also. Here is a break down of my build,

VEHICLE, What kind of car is this for? 1978 Ford Bronco Ranger XLT 4x4
Vehicle usage? (in order of importance) street performance & presence, towing a 3500lb camping trailer to and from the trail head, dunes, and mild trail riding. No big rock crawling, no deep mudding, no baja racing. Most if not all my off-roading will be dunes or dirt trail.
Is it a full body car? YES
How much Does the car weigh? 5400Lbs. (2650lbs front / 2750 rear)

ENGINE, What size engine do you have? 408ci Ford (4.030"Bore x 4"Stroke-335 Engine Series)
Is your car carbureted or Fuel injected? Fuel injected, 850cfm, 4x55lb injectors (FiTech Go Street EFI 400 HP 31003)
Do you have a carb spacer? YES
What size Spacer? 1" four hole Phenolic plastic (Summit Carburetor Spacer SUM-G1412)
What kind of intake is it? aluminum Dual Plane (Weiand 8010 Action+Plus)
What kind of heads do you have? aluminum (Trick Flow® PowerPort® Cleveland 195 Cylinder Heads TFS-51617203-C00)
What is the CC chamber rating for your heads? 72cc
Valve size? 2.08" intake 1.60" exhaust
What rocker ratio? 1.83 (Scorpion Race Series 1060 rocker arm)
What pistons are you running? Tim Meyers .030 over (KB2347) 13.3cc step dish pistons.
[decked -.001 with .041 head gasket, total .040 squish]
What is your COMPRESSION RATIO? 9.89 static/8.13 dynamic with intake closing @ 61*ABDC (all three cams above have this intake closing point)
What size Headers do you have? 1-5/8" Fenderwell exit 3" collectors (Hedman Street Headers 89366)
Are you running open Headers? NO
What kind of mufflers are you running? 3" Super Turbo Mufflers (Dynomax 17743)
Are you running- True Dual exhaust? Yes
What Size Exhaust pipes are you running? 3" pipes x 24" length, mufflers, then dumped in front of rear tires

DRIVE TRAIN, What Trans? 78 Ford C6 (wide ratio gears [2.72-first,1.54-second], PML deep sump pan, Broader Performance stage 1 valve body, Sonnex type R servo, Alto Red clutches, Kolene steels, and a KEVLAR® high performance band)
Transfer case? NP205 (1.96 Low Range)
What axle? D44RS front / Ford 9" rear (alloy axles front and rear, front with solid spicer U joints / rear with nodular housing and daytona pinion support)
What is the GEAR RATIO? 4.11's rear with a helical gear limited slip (Richmond Powertrax Grip Pro Differential GT109031) / 4.10's front with lunch box locker (USA Standard Gear (SL D44-30) Spartan Locker for Dana 44 differential with 30 spline axles)
How Tall are the tires? 33.25" tall as the vehicle sits (35x12.5-15 BFG all terrains, not a typo, the BFG's run SMALL!) NOTES: Can't think of anything at this time."

Shoot away guys!

 

Can't fathom why you'd consider a flat tappet cam for this. You're not going to turn enough rpms to justify it.

 

As a side note, with the heads I have I don't need or want to go roller. If you look at the build sheet you will also see the amount of HP my TBI can support,. So a roller would be wasted. Not only that, but I already have a great ignition system and don't want the hassle of changing my dizzy gear. Getting 400-420 Horses out of this build with a mild flat tappet is very doable. Hell if you follow the link I provided, you will see almost exactly my engine build, static comp is different but actual DCR is very, very close, with a Big ***** ThumpR flat tappet, that makes 470+hp and 500+ftlb torque. I'm not greedy.



my exhaust, as it sits.

Pic of the engine as it sits. Getting pulled for rebuild.

 

With remarks like that.....

I'm sure you mean MECHANICAL flat tappet.

I'm starting to think you have never ran a good set of heads. I have Comps 252H ran strait up in the bronco now and it will turn 5k NO PROBLEM. A 270 dur cam, whether solid or flat, will do much better power wise. Solids are also dead nutz reliable while allowing the engine to rev more freely. Also I kinda miss setting valve lash. Did it all the time in my sand rail with a 2110 VW engine. Hell I almost miss carb adjusting, no not really. LOVE my Fitech!

NOW that I think about it, I should get the ThumpR ground as a solid and run that!

 

Why does it need rebuilt ? It isn't even dirty.

 

Well you learn from every build. I put it together with a certain methodology. Some things turned out how I thought, others didn't. I pretty much knew I would be tearing it down again when I put it together, changing things etc. Now its time, winter and all. Matter of fact I have a 275DEH that I bought when I was building the last time. Figured that was what I would turn too if I didn't like the 252H. But the intake closes too late for my liking now. 61* intake closing is the sweet spot I'm aiming for. Puts the DCR right where I want it. In short, more static compression and more cam, but lower DCR for pump 87.

 

You could definitely benefit from a hydralic roller cam. I use the smallest one from Crane and I'm 435 HP on paper.

 

Yea, I did mean solid lifter cam. Sorry. Be that as it may, 5K rpm isn't a problem for a hydraulic cam nor it's lifters. Far from it. And yea, I've run all three cam types. in everything from a 302 to a side oiler 427. If you like having to pull the valve covers to check and reset lash then go for it. I'm not a glutton for that punishment. I've got better things to spend time on.

 

Why does everyone thing they have to constantly adjust the lash on a solid lifter cam?
I can see it on a high lift race engine where you your trying to squeeze every hp out of it that you can.
But on a moderate to low lift daily driver or mild street engine it seams like a waist of time to me.
Industrial, ag and big rig engines today still run some type of solid lifter cam and go for thousands of mile or hours without having the valve covers off.
The ever dependable Chrysler slant 6 was solid lift up until 1980, just before it was dropped from production, many never had the lash adjusted unless it got to running bad.
Unless they've changed in the last few years the Cummins Diesels in Dodge pickups are still flat tappet solid lift.
I had a .600 lift solid lifter cam in a 289 Mustang back in the 80's, I'd check valve lash each spring when I'd get the car out for summer driving, car wasn't driven during winter months.

 

If your not rawhiding it you don't need to run the valves that often. If you are there is wear going on.

 

Great points guys. I found the same thing when dealing with the VW stuff. If its assembled correctly, valve adjustments are few and far between. Not saying I didn't check it. I checked it every time I went to the dunes. Rarely if ever did the lash open and need adjustment. Something that's not talked a lot about, is the fact that solid cams can have more lift per duration than hydraulic cams and often out power hydraulic roller cams because of the solids ability to rev. Also a flat tappet can lift the lifter off the seat quicker than a roller cam, and it takes a bit more than 270 duration for the hydraulic rollers to pull away. Again not looking for max power, but a solid offers ~4% more power than a similar ground hydraulic, according to what I've been told.

And @ Baddad457, I never said what you say I said. I never said you didn't run cams or big engines. I said "I'm starting to think you have never ran a good set of heads". You do this a lot. putting words in other peoples mouths.

 

So we have come to the conclusion that solid cams are a viable alternative. Cool, cool. I'm still intrigued by the ThumpR tho. When you compare it to a general RV cam, the spec are fairly similar. The three big things that stick out, are how aggressive the ThumpR lobes are compared to the RV type cam lobes, the ThumpRs overlap, and the intake closing point. I think those three things would make the ThumpR a midrange monster.


ThumpR 32-600-5 vs Generic RV grind (summit 5200)

Adv Dur =278*/296* vs 282*/292*

.050 dur =226*/241* vs 204*/214*

lift intake/exhaust= .506 /.493 vs .489/.512

lobe separation =107 * vs 112*

intake centerline= 102* 107*

advance ground in.= 5* vs 5*

intake opens= 37* vs 34*

intake closes= 61* vs 68*

exhaust open= 80* vs 83*

exhaust closes= 36* vs 29*

Overlap= 73* vs 63*

 

Now here you're implying something you know nothing about. Talk about putting words in someone's mouth. I'm starting to think you're full of sheite the way you post things, then shoot down people who disagree with you when you ask for advice. Solids do work loose from normal wear. That's a fact. It's why the manufactures went to hydraulics. Have fun keeping your valvetrain adjusted. I'll stick to hydraulics. They rev just as fast as any solid. I know, I've run both.

 

I said it strait, And I didn't shoot anybody down for disagreeing, even you. I'm very passionate about these 335 engines, so at times discussions can get heated, BUT I don't let people tell me I said something that I did not say. I'm here to learn, take and give advice. And again I have only disagreed with YOU, in this thread. What about the other posters who also agree solid cams don't need constant and frequent adjustment, as per there experience. I've grown up a lot since I joined in 2003, I can get "triggered" and I can be a ***, but I do not feel this is the case here. What I've learned from people on this forum I try to pass it on. If I learn something some where else, I try to bring it here. Do I know everything? F no, but I'm no idiot. I've built a few engines in my time, but nowhere near what a professional builder does. That's why I'm waiting to hear back from Tim. I put it here to let the forum members comment on the build. I want to hear what they have to say, even you, and I just wanted to share for the sake of sharing. Also, only one of the camshafts I specified was solid, the others are hydraulic.

Edit, @ badda457 just wanted too add that I only disagreed on the one point. I do agree with the benefit of the set and forget of a hydraulic cams.

 

Actually they don't get loose that often, as valves and seats wear they get tighter.