5.9 magnum valvetrain build

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PredaFran

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So after checking the valves in my head most of them were thrashed, too low of a margin and some of them were slightly bent, they did not wanna true-up while doing a back cut. gotta buy all new intakes and 1 new exhaust so I might as well get the full set. I'm just debating if this is just the universe telling me to step up to 2.02 valves for the intakes. I've been reading about the pros and cons of running them in the engine and so far it seems like a good idea but I do not wanna hurt the velocity in the low end that much.

the heads are EQ heads with a gasket match and decked .10, the cam is from Oregon cams and the specs are:
#1990

224/230 @ .050”, 276/282 adv, ..510”/.510” lift, 110 sep, 1800/5800 rpm, 2200 stall

The engine is going .30 over and I'm running the stock type flat tops.

I'm still debating between the HUG 1110 and the HUG 1129 (also known as the PAC-1903-16 ) springs for my purpose since I don't know if the dual one will be overkill. i

this is my first engine build and I'm doing everything including the machining myself so I would appreciate ANY advice/tips/criticism/info you guys don't mind posting.

Thank you in Advance FABO
 
I would go 2.02, I like SI valves Great valves for the price. I was told by SI that they make Hughes valves, as well as a few others. My son just bought some a month ago. They were around 8 1/2 bucks apiece .
 
I would go 2.02, I like SI valves Great valves for the price. I was told by SI that they make Hughes valves, as well as a few others. My son just bought some a month ago. They were around 8 1/2 bucks apiece .
Where did you buy em from ?
 
Hughes 1110 and the pac 1903 have big difference in installed height...

huges 1110 install at 1.66
pac 1903 install at 1.80...the seat pressure for these springs at 1.66 is going to be very high....
 
Hughes 1110 and the pac 1903 have big difference in installed height...

huges 1110 install at 1.66
pac 1903 install at 1.80...the seat pressure for these springs at 1.66 is going to be very high....

I plan to get the spring pockets machined if I go with those. I'm just wondering if I'm gonna need those springs with my cam choice
 
brian at IMM installs behive springs on the EQ heads in sells....he is just down the road in Indio CA....
 
brian at IMM installs behive springs on the EQ heads in sells....he is just down the road in Indio CA....

Might as well have him do his whole bowl blend/2.02 valve treatment while they are there. The one thing Brian does do is a ton of those heads.
 
you get new seats with the larger valves
plan on new multi angle valve job which I guess you already know as you are talking backcutting, and opening up the bowls and blending
converting to 11/32? now's the time
may save some $$$
IDK about your valve lift but +100 valves work esp with larger dual valves
if you are running roller tip rockers investigate B3 kits as well
 
you get new seats with the larger valves
plan on new multi angle valve job which I guess you already know as you are talking backcutting, and opening up the bowls and blending
converting to 11/32? now's the time
may save some $$$
IDK about your valve lift but +100 valves work esp with larger dual valves
if you are running roller tip rockers investigate B3 kits as well
Wouldn't the +.100 valves mess with the geometry
And how does one convert to 11/32 valves. I haven't bought any of the valvetrain components yet so if I can use cheaper LA engine parts I'll take it.
 
brian at IMM installs behive springs on the EQ heads in sells....he is just down the road in Indio CA....

I have heard very good things about Brian and IMM but I'd rather do all the work myself since this is more of a learning experience for me.
 
Wouldn't the +.100 valves mess with the geometry
And how does one convert to 11/32 valves. I haven't bought any of the valvetrain components yet so if I can use cheaper LA engine parts I'll take it.
Yes, it will change the geometry. But if the lift is a lot higher, then the rocker will need to angle more up with the valve closed anyway. So that is at least going in the right direction. The main thing is it will make valve springs easier to get the movement and not get into coil bind.

With the Magnum rockers, it seems like changing the rocker height is a lot easier.

One the other hand..... Those Hughes springs are probably for the standard installed height of 1.650" so they probably will not work with the longer valve. And with a .510" lift, the spring length is not going to be a huge challenge IMHO if you don't change the valve length.

Different guides for the stem size. (Assuming you will go with guide inserts.) Or perhaps just go with reamed-out guides. Maybe one of the machinists will make a recommendation.

Your cam ramp rates are moderate, not fast. So the spring is more a question of whether you want to rev this as much as you can.

What rockers are you planning?
 
Yes, it will change the geometry. But if the lift is a lot higher, then the rocker will need to angle more up with the valve closed anyway. So that is at least going in the right direction. The main thing is it will make valve springs easier to get the movement and not get into coil bind.

With the Magnum rockers, it seems like changing the rocker height is a lot easier.

One the other hand..... Those Hughes springs are probably for the standard installed height of 1.650" so they probably will not work with the longer valve. And with a .510" lift, the spring length is not going to be a huge challenge IMHO if you don't change the valve length.

Different guides for the stem size. (Assuming you will go with guide inserts.) Or perhaps just go with reamed-out guides. Maybe one of the machinists will make a recommendation.

Your cam ramp rates are moderate, not fast. So the spring is more a question of whether you want to rev this as much as you can.

What rockers are you planning?

I'm gonna switch to adjustable small block chevy rockers since those are a lot cheaper than that stuff Hughes sells. I want to rev this to around 6000 which is when the cam should start to peak down.
ill check to see if we have the tools to ream the valve guide. still waiting on the check to see if we have the tool to cut down the spring pocket. if we don't the cost to do it to both my heads plus the actual cost of the PAC springs is around 160 so if any of the springs will work at installed height ill use em
 
Why mess with going to 11/32 stems when you have 5/16 now? The SI valves are available in +.100 if you really need them. They neck down from 5/16 to .288 too.



















IMG_0441.jpg
 
Why mess with going to 11/32 stems when you have 5/16 now? The SI valves are available in +.100 if you really need them. They neck down from 5/16 to .288 too.
View attachment 1715411246

im gonna send them an email asking about part numbers SEV-3954-S, SEV-2654 and E-2654
but if I can fit cheaper valves that are still quality for some extra elbow grease ill be happy.
 
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Oh Magnum heads OOPS
you have the lighter valves (alrady vs LA rocker shaft heavy 3/ stems)
and at your lift do not really need to go longer
the beehives would be lighter and lighter retainers
which (theoretically) means you could run a little less spring pressure or rev a little higher
you might ask YR (?) why he relocates the rocker arms
what adjustable kit? or?
 
It sounds like cost is a major consideration, and with the cam your intending on using you won't need stronger springs, any additional machining or longer valves. I've read here posts by a member: Magnummopar (not seen in a while) who had mentionioned
having sold all levels of EQ heads that for most staying with the 1.92 intake was all you really needed, maybe a 1.97 intake, but the 2.02 wasn't necessary (lower levels of performance vs extracting maximum) Here is one thread of note: EQ head build + home porting advice sought. This is just an example of various opinions on the EQ heads. Just sourcing the standard length SI magnum valves with the Hughes 1110 spring kit is all you're likely going to need.
 
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On my EQ heads we used longer valves from an LS head and ended up shimming the rockers up instead of cutting the spring pockets.
 
It sounds like cost is a major consideration, and with the cam your intending on using you won't need stronger springs, any additional machining or longer valves. I've read here posts by a member: Magnummopar (not seen in a while) who had mentioned
having sold all levels of EQ heads that for most staying with the 1.92 intake was all you really needed, maybe a 1.97 intake, but the 2.02 wasn't necessary (lower levels of performance vs extracting maximum) Here is one thread of note: EQ head build + home porting advice sought. This is just an example of various opinions on the EQ heads. Just sourcing the standard length SI magnum valves with the Hughes 1110 spring kit is all you're likely going to need.
my reasoning was that since in need of new valves and the 1.92 are the same cost as the 2.02 I might as well go with them but if most people think that they will cost me velocity at almost no benefit for most of my rpm range ill just go with 1.92s and a 30-degree back cut.
I appreciate the advice a lot thank you for your reply. I wonder what happened to magnummopar he seemed like he had a good price on parts


On my EQ heads we used longer valves from an LS head and ended up shimming the rockers up instead of cutting the spring pockets.
out of curiosity, how did you shim the rockers?
 
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my reasoning was that since in need of new valves and the 1.92 are the same cost as the 2.02 I might as well go with them but if most people think that they will cost me velocity at almost no benefit for most of my rpm range ill just go with 1.92s and a 30-degree back cut.
I appreciate the advice a lot thank you for your reply. I wonder what happened to magnummopar he seemed like he had a good price on parts



out of curiosity, how did you shim the rockers?

Milled some spacers that went under 2 of the stands, I don’t have any pictures of the actual end result.

C19667BF-B8ED-4AB4-B102-1263CC7C7577.jpeg
 
I am not seeing where the 1.92 to 2.02 valve change is going to effect 'velocity'.....??? I assume you mean port velocity? The cam planned is not severe and is going to be the control over what you have. I'd guess that you would see very modest gains with the larger valve and the associated clean-up under them.

I'd worry more about the Chevy rocker plans than that.
 
Not that familiar with the eq head, but I’m not sure you can really cut the spring pocket much on the J/X/U heads. I could be wrong. This is a magnum head?
 
"On my EQ heads we used longer valves from an LS head and ended up shimming the rockers up instead of cutting the spring pockets."

The 2.02 valves are only going to help with the proper valve job and bowl work
and may cost you low end in any case
do some homework

are these magnum heads or rocker shaft
I see chevy rockers mentioned
you might ask YR about relocating the studs if magnums
Me I like longer springs and longer valves
and I like to cut down valves and put on 30 degree seats for short cams with .500 lift
depending on usage, gears etc
lots of ways to skin a cat but to me 2.02 valves with a short cam can be a mismatch
do some research
I'd use the rocker with the largest arm that would fit, maybe BBC/460 ford with the studs set back if magnum
if the heads flow above .500 you could use the 1.7/ 1.8 rocker ratio for more lift
(FKN SBC's)
 
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