Camshaft instal inquiry

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DentalDart

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So my brakes are done... I think... now onto new ideas :realcrazy:

I have the summit 1789 camshaft and lifters. While reading the overview on summit it states that I can use it with my stock springs/rods/retainers etc...

My question is should I get springs and retainers even though it says I can use mine? Is there an advantage to using new ones besides having new parts in the engine?

I know I should use a new timing chain when doing it. Double roller... Mp, edelbrobk, cloyles... do these work? The MP from mancini says for .10 over, I'm assuming that doesn't work with my engine?

Any other parts I should start accumulating before opening up the engine? Certain gaskets? Certain cuss words? I see some of you do it in 2-6hrs. So I'll plan on 3 months?

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Woah doc.....

How about you enjoy your car for awhile before you get into your next project.

Just my 2 cents
 
compcams 901 springs fit using stock retainer and no additional work to the heads...63.00 at summit

the timing set with the -10 is for an engine that has been aligned bored....not needed

the summit timing set you listed has a billet cam gear.....is that really needed...their 43 dollar set is the same except it has a steel gear .....
 
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No. I also don't see anywhere on the Summit site where it says you can use the stock springs. If somebody told you that, they're wrong.
 
No. I also don't see anywhere on the Summit site where it says you can use the stock springs. If somebody told you that, they're wrong.

In the question and answers there is a statement...

Thank you for your question. The Summit 1789 camshaft can be used with stock rate valve springs.

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Summit Racing Answer - April 08, 2019
 
ok...wont hold it against you.....just have to read a little further...lol

but unless I knew the history of the valve springs i would change them out...lol
 
just remember I got the tools to degree in cam,,,easy with head off...

also got pneumatic valve spring compressor if the heads are off....and have tool to remove and replace springs on head......
 
Woah doc.....

How about you enjoy your car for awhile before you get into your next project.

Just my 2 cents

Oh we will enjoy it for sure! We are taking it to the father daughter dance next weekend and slurpee runs are already happening!

I just have more parts sitting on the side of the garage waiting to go in, figured I would start keeping an eye out in the fs sections and other places to start accumulating the rest of the parts needed to do the install. I will be getting a radiator soon and figured when swapping that in I'll already have most of the parts off to install the cam. Wouldn't that be a logical time to install it?

Just think when everything is done I won't have to break anything in/on the car anymore... or ask you anymore questions? :poke::rofl:

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compcams 901 springs fit using stock retainer and no additional work to the heads...63.00 at summit

the timing set with the -10 is for an engine that has been aligned bored....not needed

the summit timing set you listed has a billet cam gear.....is that really needed...their 43 dollar set is the same except it has a steel gear .....

I have seen posts saying to not cheap out on timing sets so figured 60-80 was middle of the pack between cheap and best?

Ok comp springs not the ones suggested by them?
 
just remember I got the tools to degree in cam,,,easy with head off...

also got pneumatic valve spring compressor if the heads are off....and have tool to remove and replace springs on head......

I have to accumulate the parts, which could be 2 days... maybe a little more lol... if you're available I'd love to learn from someone with the know how!
 
just remember I got the tools to degree in cam,,,easy with head off...

also got pneumatic valve spring compressor if the heads are off....and have tool to remove and replace springs on head......
Where did you get a pneumatic valve spring compressor, I so need one of these.
 
If your taking the springs off on the motor (easy with this type tool) stuff some rope in the spark plug hole and run it up tight to the TDC valves with a breaker bar, then you can pop the springs without compressing the valve. Hook it, pull the handle down and use a magnet to fish out the locks. If your handy with a welder, you can make one of these pretty easy.
roform_67460_Shaft_Mounted_Valve_Spring_Compressor_For_Small_Block_Mopar_Chrysler_JEGS_1024x1024.png

Proform - Shaft Mounted Valve Spring Compressor For Small Block Mopar/Chrysler (778-67460)
 
I would change the springs to go with the cam, at least you would know what they were


on a side note don't you have a 340? the specs in my 69 manual show the Summit 1789 cam is about the same as the stock 340 268/276 duration and 429/444 lift - may not be worthwhile to go through the expense of the swap
 
what i said
if he owns the summit & can't send it back run it ramps are moderatly shorter
it's a chevy cam they have to work harder to match a MOPAR
 
Well I wanted a comp cams extreme energy 268 as that's what I read that everyone loves. Then the 1789 cam popped up brand new for more than half off local to me and it looked decently close to the 268.

Id still love a 268 extreme energy but I dont have one :(
 
I would change the springs to go with the cam, at least you would know what they were


on a side note don't you have a 340? the specs in my 69 manual show the Summit 1789 cam is about the same as the stock 340 268/276 duration and 429/444 lift - may not be worthwhile to go through the expense of the swap

Now you got me questioning the cam, like I should just buy the xe268 lol
 
what's in it now?
and how often are you running up to shift-rpm?
If 95% of your driving is below 4000 rpm, why install a 5500/6000rpm cam, jus asking? I mean we all do it to some extent, but why.
If the current combo spins the tires all the way thru first gear, a bigger cam is not gonna benefit your combo in first gear.
If the current gears do not let your engine wind up into the power zone,in second gear, then a bigger cam with no other changes will just be slower.
If the current combo spins the tires, thru two gears, already, then what possible advantage would you get from a bigger cam?
If your 60ft is in the 2.4 or slower zone, then you can make up more time here than with more power at 5000rpm which depending on your gears, you might never get to in second gear, below the speed limit.
For example;
3.55s with a 904 and 27s is 4000rpm@ 60mph@ @5% slip. So having 15 hp more at 5000, helps you nothing. Whereas 15 ft pounds at stall could.
IMO, you should be thinking more about maxing out your power,and gears, in the area you spend the most time.
For example, 30 mph.
By 30, if you have worked your chassis up to speed, and got the spinning under control, then,at 30, you want to be on the fat part of the power curve when the trans kicks down into first. But you can't be, there is no combination of gears in the Mopar catalog that can get you there.
So second best is to stall somewhere on the fat part or close to it on the rising side. So if this occurs at 2400, then you want a 2400 stall . But if this occurs at 3000, then 3000; if 3500 then 3500 and so on.
Lets just say your engine, with it's current cam, makes 200ft lbs of torque at 2400, then the simple math is 200x2.45=490 out the trans. But if it makes 240 at 2800, that would be 588 out the trans. And if it makes 280@3200, then 686 out the trans. 686 is 40% greater than 490. You cannot match this increase with one or two cam sizes. In fact, each bigger same type cam , with no other changes, is most likely to subtract bottom end torque to get that topend power.
Your next tool is gears, to put the power at the rpm you need it to be.
Going back to 30 mph, and say a 3200 stall TC, you might want to be at 3200 at that 30 mph, at KD into first.And the math; drumroll, comes to 3.23s. And 3.23s will get you 60=3700 in second gear. So if you have a cam that powerpeaks at 5000 what good is that gonna do you? 3700 is barely on the torque peak. A bigger cam will just slow you down.

So, you need a compromise... or a bigger engine with inherently more midrange power.
The compromise might be 4.30s. Now the rpm at 60 in second gear is 4900@5% slip, and 30 is 4140 in first. Hey that's looking pretty good. But now, you have a different problem; namely way too much Torque Multiplication in first gear at zero mph. So that 3200 is not helping you anymore.

Lets go back and take the engine torque all the way to the road.
With the 2400TC we had 490 out the trans which with 3.23s is 1583 to the road. With the 3200TC it was 686, so with 3.23 would be 2216; just right.
Ok so now, with the 3200TC and 4.30s, this is 686x4.30=2950! easily 800 more than you need. So lets go back to the 2400. So then 490x4.30=2107 just enough to squawk fat street tires, maybe spin them up under the right circumstances.
So we come to another compromise.
Lets go get that 2800. This was 240ftlbsx 2.45 first gear x4.30 rear gear, so 2528 to the road, and there ya go.That will be a tire-fryer.
Ok so far, we are at 4.30s and a 2800TC, for 240ftlbs at 2800 torque.
But we're not done yet.
Firstly; the 240@2800 footpounds I'm talking about, is an arbitrary number I assigned to your engine. You could have more or less depending on your combo.
Secondly; Remember I said, in the beginning, simple math. The TC is More than just a fluid coupling. It is also a Torque Convertor. It has the ability to multiply the engine torque coming into it to a higher value, before it sends it out the back. This TM (Torque Multiplication) is greatest at zero mph, and rapidly diminishes as the vehicle moves forward. I have seen TM numbers as high as 1.8 . Typically, by top-speed, the number may have diminished to 1.05 or so.

So lets stick with the 200/240/280 numbers, but lets install some TC TM.
Beginning with the 2800 which previously stood at 2528ft lbs to the road. Lets add a 1.8 factor at zero mph. And I get an instantaneous 4550 ftlbs to the road!, obviously far in excess of what is needed to break the tires loose. But like said, this ratio rapidly diminishes. By 60 ft out, it might be down to 1.3, IDK. But at 60 ft out, your rpm is wherever you're holding the pedal at,and tires are still smoking, so it really doesn't matter what it is.
Furthermore, with 4.30s, your no-spin rpm at 30 mph is easily 4100 or more, so by this time, you don't care about stall.
Furthermore, kicking down into 1.45 second to pass a car at say 58mph, the rpm might rise to 4700, so again, stall is irrelevant.......... That means, the only time stall is relevant,for this combo, is at zero mph, and as we have seen 4550 is crazy large, so lets put the 2400 back in,lol. This TC was 200 crank x2.45 x4.30 x1.8=3790 at zero mph, still far in excess of what you need to launch with.
To recap; now we are at 200ftlbs at 2400, a 2400Tc, and 4.30s At 30 mph KD, the rpm will rise to 4100 and you are G-O-N-E, in all likelihood smoking the tires at WOT.
Ok, so what is 200 ftlbs at 2400. Well criminy a smoggerteen can do that.

So, remind me, what was the purpose of the 4.30s again? That's right, to maximize power at 60 mph, to minimize the time to get there. If you don't care if yur car is a lil slower, then run less gear. But when you do, make sure your stall is high enough at the other end, to still get outta the gate in a manner that keeps you smiling.

Each bigger same type cam (~7*) will raise your power peak up about 200 rpm,at the expense of wanting nearly the same more stall, all other things remaining equal. A lot of the midrange is gonna be similar.
You can increase low-rpm torque, by trapping more mixture, or compressing it to a higher psi. In this way you can get back some or all the low-rpm torque, that the next bigger cam gives away. This only works in a narrow window, as too much pressure can rapidly drive the engine into detonation on pumpgas. Cranking cylinder Pressure at WOT, is a better measure of when to quit than Static compression ratio. Each bigger size cam ,with no other changes, will reduce you cranking pressure.
As to pressure, here is a guideline
105 is a pure dog no matter how many cubes you have. Well, no matter how many normally aspirated cubes you can fit in your Duster,lol.
115 still doggy, I've seen lawnmowers with more pressure.
135 is typical of a smoggerteen.And you probably know what that feels like.
145 is like a 360LA, or an early 318
155 is like an early 340,which could be up to maybe 165 or a bit higher
165 is about the max you can run on pumpgass (R+M)/2,and iron heads, with an optimized chamber.YellowRose and at least one other member, are saying 170 can be done, but you better have your ducks all in a row.
175 is alloys only, generally.
185 is getting to the top of alloys, but some designs are still on 87E10. I like this; it makes my 367engine run with bigger less pressurized engines. And it spins 295 tires to any speed-limit in Manitoba... and beyond.
195 is about the max for alloys on best gas. I don't see a point in running this high on purpose with a street engine. I mean if your 273/318 fell together at that,lol, I wouldn't change it; at least not until I drove it.
These are numbers mostly accumulated from real world engines right here on FABO.
I personally have run 165/170 with iron,back in the days that we had real gas. And am currently running 180 with alloys, on 87E10, and I gotta tell ya; it is so much fun.
More pressure is better than more cam, because it increases torque throughout the entire rpm range; this is so obvious when you jump a smoggerteen up to even just 155psi.
Whereas the bigger cam trades away low-rpm pressure to get the higher rpm operating range; and it is that which makes the additional power. Consider
300 ftlbs at 5000 is 286 hp; while
300 at 5200 is 297hp; and
300 at 5400 is 309hp
So that comes to ~11 or 12 hp just in the rpm, assuming the support works keeps up.
Well, I better quit before Rumble jumps on me again. He says he likes me, but I better not push my luck. Shrink the page and maybe it won't look so long. lol. Nah it's still long. Merry Christmas,lol.
 
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