My doomed 408 build

[BlooDSMeaR]

Or...... you were running out of valve spring.

408 with 63cc heads, zero deck, 5cc pistons, .040 gasket.......about 11.6cr.

In any case, I hope it works out to your satisfaction.
When I was first getting into it many years ago, I did it the way I wanted.
Sometimes it worked out really well, sometimes not so much.
But that’s how you learn.

408 63CC heads, zero deck, flat top pistons (unknown displacement) .039 gasket. Yep. about 12-1 is what Tim @ Hughes said. My builder claimed it @ 11-1 and I can run on pump gas NP... it pinged with 34 DEG timing. 32 not so much.
The first cam I had in it was a hydraulic flat tappet, one that should have been right where I wanted the springs.

I don't know if you feel that I am going down the wrong road with my game plan, What exactly would you do differently?

No matter what I do I will make more power with this cam and the correct valve springs. I am hoping to get it to run on pump gas with the new cam. I really would like to get my 4000# Roadrunner down the strip in the 12's
I am hoping to run the engine more than say 30 miles or at least 30 minutes before another major malfunction with the engine or transmission happens. I have so much cash and time into this thing, that at one point not to long ago was about to tear it down and sell it all off for parts.

 

[BlooDSMeaR]

on top is the roller cam the second one installed
Bottom cam car is the first build.
1st engine build dyno sheet. I'm still looking for the second engine build sheet.

 

[BlooDSMeaR]

The car...

 

[BlooDSMeaR]

2nd engine build with roller cam

 

[PRH]

There are obviously some issues going on with the motor on the second dyno sheet.

Look at the fuel flow on both sheets, and the bsfc.
The first cam made 30 more hp while using 17lbs/hr less fuel.
The bsfc numbers for the second cam from about 5200 up are atrocious.
It’s a big red flag to see those numbers tank like that.
Unfortunately, the way he’s got the columns arranged on the sheet, there is no air flow data to look at.
If there were, I think it would be obvious something in the valvetrain was unhappy.

You had three valvetrain failures before you even got 100 miles on the car.
My approach would have been to use a more conservative cam profile, in an effort to increase my chances of success, and not been worried about if I were leaving 10-20hp on the table.

The Hughes cam you have coming should certainly make more power than what I would have used........given your situation.
Fast rate cams, designed to take advantage of the full diameter of the lifter are inherently less forgiving in terms of lifter bore placement and sizing.

I’m also not very confident the extra duration will remedy the octane requirement....... but to be honest, I don’t know that can be properly solved with any cam.

An 11.6:1 408 with a decent single plane, rpm heads, and that Hughes cam should easily make solidly over 500hp.

My feeling on the first cam peaking early is, you probably didn’t have quite enough spring load.
If you look at the recommended spring on the cam card, it’s a spring that has about a 400lb/in rate...... which is a fair amount higher than the single spring that comes on the RPM heads.

The other possibility is the motor was tested with 1-5/8” headers...... which would tend to lower the point where the peak occurred.

Oh, and IMO both of those runs are sort of “glory runs”.
Barely over 100* water temp?
C’mon....... that’s not reality for a street car.
Real world temps could have the motor end up wanting totally different timing and jetting.
I realize that you had nothing to do with that....... it just makes me question what’s going through the dyno operators mind when I see stuff like that.

I actually did that very test on a 12:1 bracket race 416.
Going from 165* down to 115* was almost a 10hp gain.

Car looks nice btw.

In the test description on the 2nd test, it says something “Ford”?
What’s that about?

 

[j par]

Ouch.

FWIW, only cam to ever flatten a lobe on me was Hughes camshaft.

I would never recommend anything made or designed by Dave Hughes.

Best of luck.

Well we all know Hughes is a massive repacker. They don't make their own cams they may send the recommended designs to somebody who makes them but they certainly don't grind them in house. They get somebody like where I go to Oregon cam have them ground and sell them as they're hot ticket for way too much money...

 

[j par]

Remember my comments here are coming out of complete and utter frustration for a fellow Oregonian. I mean we have Smith Brothers pushrods in Bend or sisters I can't remember? With Ken with Oregon cam grinding right across the bridge in Vancouver who is an expert in cam design, not somebody repacking cams but someone who races them himself and grinds them in the shop right next to him. And I've already given my best recommendation for someone local With A 40-year plus reputation for building not only domestic but exotic Motors. Again not recommending at all that you spend money at any of their shops but at least talk to them for free. First and foremost keeping your money local and keeping your business somewhere where somebody can actually see the parts that you're talking about and see your problems. Again I am hoping that this whole Hughes Gama Rama works out for you but I'm not going to sarcastically wish you good luck either I should surely hope everything works because this is far too much money being spent.

 

[j par]

Also let me reiterate I do have Hughes rockers and it took me a while to save for them and I'm very happy with them but again there tech support was terrible at best they seemed almost too busy to take care of me and when they did it was a rushed care call. They'd already gotten their money I'll be interested to see how they treat you now.

 

[BlooDSMeaR]

Well we all know Hughes is a massive repacker. They don't make their own cams they may send the recommended designs to somebody who makes them but they certainly don't grind them in house. They get somebody like where I go to Oregon cam have them ground and sell them as they're hot ticket for way too much money...

I honestly don't think $169 for a mechanical camwas to over priced.
My thoughts are buy from some placethat offers a flat cam guaranty. I priced many diffrent combos on jegs, summit, mancini, e bay, they all came to a grand. My cam is wiped several lifters are damaged. I have to do a full valve train rebuild. I rather buy once cry once with some sort of guaranty. I have taken a massive beating with this car starting with how much I bought it for. I need some sort of warranty for something.

 

[j par]

I honestly don't think $169 for a mechanical camwas to over priced.
My thoughts are buy from some placethat offers a flat cam guaranty. I priced many diffrent combos on jegs, summit, mancini, e bay, they all came to a grand. My cam is wiped several lifters are damaged. I have to do a full valve train rebuild. I rather buy once cry once with some sort of guaranty. I have taken a massive beating with this car starting with how much I bought it for. I need some sort of warranty for something.

I agree with the warranty and all that but those warranties have one s*** ton of loopholes. I'll show you my invoice I paid $79 to have my cam reground for the second time because I wanted a different profile and$4 each to resurface my lifters. Again for the third time the same cam on its third profile is doing absolutely great! One thing I've learned in life there's no guarantees! again the suggestions I'm suggesting are 100% free even now in the after thought. Again my frustrations are for you not against you.
I got to leave right now and go help the customer install his crate motor in his 66 Nova. Unfortunately all his warranties for his crate motor need a Certified mechanic to check the checklist off for his warranty to not be invalid. Lupo's Lupo's Lupo's in more hope she has to jump through and pay for to make sure that warranty is good...
mind you I'm not a Certified mechanic so I can't help him there but I can't help him get it in and get it in safely. Now my son is a Certified mechanic but he was born long after cars stopped having carburetors LOL he wouldn't know the first thing! But he is certified...

 

[justinp61]

I hope you don't ever need the warranty, but if you do I think you'll have a hard time proving the cam is the cause of any failure. There are a few companies who are notorious for claiming user error (and there are many for a cam) and not standing behind their product.

 

[BlooDSMeaR]

There are obviously some issues going on with the motor on the second dyno sheet.

Look at the fuel flow on both sheets, and the bsfc.
The first cam made 30 more hp while using 17lbs/hr less fuel.
The bsfc numbers for the second cam from about 5200 up are atrocious.
It’s a big red flag to see those numbers tank like that.
Unfortunately, the way he’s got the columns arranged on the sheet, there is no air flow data to look at.
If there were, I think it would be obvious something in the valvetrain was unhappy.

You had three valvetrain failures before you even got 100 miles on the car.
My approach would have been to use a more conservative cam profile, in an effort to increase my chances of success, and not been worried about if I were leaving 10-20hp on the table.

The Hughes cam you have coming should certainly make more power than what I would have used........given your situation.
Fast rate cams, designed to take advantage of the full diameter of the lifter are inherently less forgiving in terms of lifter bore placement and sizing.

I’m also not very confident the extra duration will remedy the octane requirement....... but to be honest, I don’t know that can be properly solved with any cam.

An 11.6:1 408 with a decent single plane, rpm heads, and that Hughes cam should easily make solidly over 500hp.

My feeling on the first cam peaking early is, you probably didn’t have quite enough spring load.
If you look at the recommended spring on the cam card, it’s a spring that has about a 400lb/in rate...... which is a fair amount higher than the single spring that comes on the RPM heads.

The other possibility is the motor was tested with 1-5/8” headers...... which would tend to lower the point where the peak occurred.

Oh, and IMO both of those runs are sort of “glory runs”.
Barely over 100* water temp?
C’mon....... that’s not reality for a street car.
Real world temps could have the motor end up wanting totally different timing and jetting.
I realize that you had nothing to do with that....... it just makes me question what’s going through the dyno operators mind when I see stuff like that.

I actually did that very test on a 12:1 bracket race 416.
Going from 165* down to 115* was almost a 10hp gain.

Car looks nice btw.

In the test description on the 2nd test, it says something “Ford”?
What’s that about?

I will first and for most state i am not a dyno tech. Other than HP and TQ I have seriously no clue what the numbers mean. Nor am I am experienced engine builder. I have R&R'rd many engines and transmissions, but I have had a shop do the rebuilds. Knowing I had spent really good big money on this one ( seriously way more than I really could afford) on very good parts. I didn't want too risk messing them up.
There were huge issues that will take a small book to wite about the management at the shop that did the work. I'll give you a quick run down.
Shop operator was leasing to own the shop. Shop operator defaulted, the pissed off owner repossed shop. Pissed off retired owner got my second build mid way. Shop operator pocketed my funds for the job. I had a contract with the shop for the work with a $2000 deposit and a paid reciept. Pissed off shop owner slaped my engine together as fast and as cheap as he could. That's why the dyno tune sucked ***, he only did 3 pulls and he seriously excreted up the carb by Jet changes. that's why he didn't want to change out the springs, the detail work was horrendous. I know i would have done a better job. My mistake.
I am 100% sure that the springs caused the failure. Every single lifter had smash dents in the rollers. The cam is ate up.
Sad part is now I will be doing the work, as I can't afford to pay a shop another grand to do the cam change.

 

[PRH]

Was the same carb and jetting used for both tests?

I was looking through some of my dyno sheets and I found a test on a 410 with a mild small-ish solid roller, that I didn’t run, that had bsfc numbers almost as bad as the ones on your second test.
On the test here, the carb was way way too rich....... so the power was down, and the bsfc up.

Did you only get one page of data for each test?
The air flow data is likely on a different page(if the air flow turbine was used for the test).

 

[PRH]

It’s a shame really, overall....... the dyno data for the first test doesn’t look too bad, other than the ridiculous water temps.
Had it been tested at 175* or so, it would have likely made 10-15 less hp.

I have some springs here off a set of RPM heads for flat tappet cams.
On the SB RPM’s I’ve had here the spring heights were set up at a nominal 1.800.
At that height, the springs test at about 115-120lbs closed, and 275-280@.500 lift.
This would be adequate for some old school style hyd cam, but is going to be a little light with a fast rate cam using heavier than stock roller rockers.
I usually shim the springs to 1.750(130-135lbs) in that type of application(and I wouldn’t expect that XE284 to make it to 6000 without issues using that spring set up that way).

There is no way those springs can provide adequate load for the hyd roller cam you had, and still maintain control in the upper rpms.

I’m not really a big fan of the Thumper cams, but in that combo, with that cr, it should have made more power than the hyd flat tappet cam.
The fact that it didn’t, along with the poor bsfc numbers, tells me there was “something” going on right from the very beginning.

 

[BlooDSMeaR]

The carb was the same, I was not there for those dyno runs. My Dad was. But what I found when I installed the engine, was the gasket on the bottom of the carb was not completely cleaned off. Creating what I belive a huge vacume leak. My Dad said they played with the carb quite a bit. Changing jets a bunch of times. When I did pick up the engine he only gave me 3 runs printed out. He didbsay my carb was messed up and that i needed a new one. When I cleaned the carb base, I did find it was running very rich.
Now that I have a better understanding of what the dyno sheet is saying, more and more is making cence.

 

[PRH]

My guess is, in addition to the leaking gasket, he was trying to tune the motor to correct a problem that had nothing to do with the carb....... the valve springs.

What carb are you running anyway?

Since it sounds like it’s had the bowls off a bunch of times, I’d just put a kit in it.
The gaskets on Holley style carbs are an intergral part of how they function, and can result in erratic operation of the carb when they’re compromised.
Best to just replace them.
Carb kits are cheap.

I am 100% sure that the springs caused the failure. Every single lifter had smash dents in the rollers. The cam is ate up.

It’s amazing how quickly new parts can be turned into junk when they’re not properly matched.

 

[BlooDSMeaR]

My guess is, in addition to the leaking gasket, he was trying to tune the motor to correct a problem that had nothing to do with the carb....... the valve springs.

What carb are you running anyway?

Since it sounds like it’s had the bowls off a bunch of times, I’d just put a kit in it.
The gaskets on Holley style carbs are an intergral part of how they function, and can result in erratic operation of the carb when they’re compromised.
Best to just replace them.
Carb kits are cheap.


It’s amazing how quickly new parts can be turned into junk when they’re not properly matched.

I am running a worked over Holley 750 DP on top of a Holley strip dominator. No numbers to be able to identify the exact model. It was cleaned up and re-gasketed. Pin the first build it preformed perfectly. When pissed off owner tried to tune it he messed it up.

 

[j par]

I can't tell you how much this frustrates
me!
I just got home from work and I can't tell you how painful it is to read this stuff...
absolutely never had my motor on a Dyno and would never pay money for something like that. But I can tell you I've got one crap load Time Slips from the drag strip...

 

[RAMM]

I can't tell you how much this frustrates
me!
I just got home from work and I can't tell you how painful it is to read this stuff...
absolutely never had my motor on a Dyno and would never pay money for something like that. But I can tell you I've got one crap load Time Slips from the drag strip...

You would never dyno? LOL --you are the one that needs some reality. $500-$700 to dyno sure is a deal breaker--lol. J.Rob

 

[j par]

You would never dyno? LOL --you are the one that needs some reality. $500-$700 to dyno sure is a deal breaker--lol. J.Rob

it only cost me $30 for all the drag strip runs I want to take in one night. Timeslips never lied but dinos are just a tuning device for people who want to talk about numbers. take a run down the track make an adjustment. Take another run down the track see if a judgment worked...
I've never paid 5 to $700 for a warm fuzzy feeling...

 

[j par]

^^^^wideband O2 sensor is telling me what my fuel ratio is, my timing light is telling me where my timing's at, and I'm fully aware of exactly how I curved my distributor...

 

[justinp61]

You would never dyno? LOL --you are the one that needs some reality. $500-$700 to dyno sure is a deal breaker--lol. J.Rob

My day at the dyno was around $450 and was worth every penny. The guy that owns the engine shop builds all kinds of engines from drag to tractor pulling and runs a Mopar stocker. It was good to have that knowledge and experience right there and I made some new friends.

 

[j par]

Good gravy! The last thing the original poster needs is a stupid argument about dynos! He needs good advice on how to get his Parts together and even get his motor running good. The stupid subject has been beat over the cows so many freaking times I can't even believe it. can we just start a different thread and have the argument out for the millionth time somewhere else??? the machine shop where I had mine done also does all kinds of exotic Motors this that and the other and has dino. I've been there many of times watching Motors get revved to the moon so the new owner can have a warm fuzzy feeling of knowing exactly how it ran in that atmosphere on that day with that load with those headers blah blah blah under those certain conditions that will definitely be not the exact same conditions that are in your car. I remember one day when my car was running a half-second slower and I thought I'd lost a cylinder or something was completely wrong? Come to find out I went to the atmosphere calculator and sure enough the conditions in the air were so bad that that's exactly what I should have been running a half a second less...

 

[BlooDSMeaR]

I stopped by to try to talk to pissed off owner, and the name of the shop was changed and all bullet custom engines logos were removed.

 

[BlooDSMeaR]

Good plan.

Assuming you’re running 1.5 ratio rockers........

- if the heads still have the stamped locks, I’d upgrade those to machined locks(Crane 99097-1 to fit the Ede retainers)

You’ll likely end up needing different pushrods.

PRH, you have been very helpful I appreciate your knowledge.

After re-reading everything, I would like to state the car is 20% street, 80% strip. I originally bought the car so I could use my father in laws wrecked one to rebuild his car. Then My father in law said he wouldn't drive a purple car. I got stuck with it. Since it was started being built in to a drag car, I went that route. The car is for doing the summer Cruz and drag strip as I'd like to start bracket racing


If the Cam flattens again, I will be replacing the block. And get a new cam from Hughes.
Yes, I have crane gold 1.5 roller rockers.

Since my heads were new out of box and they were unmolested at this point, I am sure that the locks have not been upgraded. I just ordered a set locks from summit along with an oil pump primer tool. Thanks for the heads up!!
I also had ordered a kit for building push rods from Hughes.

As for doing the dyno, I wanted to get the car set up and baselined before I went to the track and wranged it out. I wanted to make sure there were no build problems and that the cam install went correctly. I also wanted to find where the power band was so I knew when to shift. To me that was worth the extra $400.

You have to remember that the pissed off Owner didn't make a cent off of me, as the defunct shop operator was the person who I paid. My engine was mid way getting rebuilt when pissed off shop owner took over the shop. That money didn't get paid to the shop owner. The shop owner did every thing he could to limit his cost of finishing my rebuild. Not changing the springs as required was one of his cost cutting methods.