L82 heads
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Intermediate
Joined: Jun 2019
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Summit Racing vortec heads
I have a 1980 L82 with headers and I am fixing to put in a Comp EX 268 cam. I am thinking of going ahead at this time and put on Vortec heads. Does anyone have experience with Summit Racing vortecs? I have read the reviews and have read anything from they needed resurfacing to the springs weren't good enough to the umbrella valve seals needed replacing. I am interested in low to mid range torque and will not be running it all out at top end. I know I will need a new intake and valve covers and some type of rocker arms. Any advice from anyone who has used them? Thanks.
Last edited by alan600; Sep 9, 2019 at 12:32 PM.
Drifting
Joined: Aug 2019
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It never hurts to have your local machine shop check out your new heads . Which Vortec heads are you looking at ? small valve small port , factory GM Heads ? Factory Vortec's need self aligning rockers which are different than your current rockers , different Intake manifold bolt pattern and different valve covers bolt pattern
On my 1980 Vette L82 I'm going with a Promaxx 185 cc cast iron Vortec head from Jegs , they have screw in stud and guide plates with 2.02 1.60 valves just like your factory L82 head , Promaxx uses conventional SBC rockers , both intake bolt pattern ( Vortec and Traditional ) and the same with Valve Covers they offer both bolt patterns so you can use the original Valve Covers with the Promaxx Vortec heads , in my case I'm going to use the factory L82 cam but with 1.6 roller tip Comp rockers which will bump lift from 450/460 up to .485/.495 where factory rockers are 1.5 ratio
On my 1980 Vette L82 I'm going with a Promaxx 185 cc cast iron Vortec head from Jegs , they have screw in stud and guide plates with 2.02 1.60 valves just like your factory L82 head , Promaxx uses conventional SBC rockers , both intake bolt pattern ( Vortec and Traditional ) and the same with Valve Covers they offer both bolt patterns so you can use the original Valve Covers with the Promaxx Vortec heads , in my case I'm going to use the factory L82 cam but with 1.6 roller tip Comp rockers which will bump lift from 450/460 up to .485/.495 where factory rockers are 1.5 ratio
Dr. Detroit
Joined: Mar 2012
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From: New Braunfels Texas
I don't like Vortec heads......I mean, they work, but they just require so much proprietary components that there are better options in the the standard Gen 1 configuration......
You will spend a little more outright, but end up with an aluminum head that flat out works and standard components are compatable (Intake, rockers, coolant bypass hole).
I have a problem with the 8 bolt intake hold down as well.......it just doesn't sit well with me on an aftermarket carb style intake (Which GM never offered).
Anyway...that is my opinion on it and if it were my money, buy a part of Dart 180's (NOT SHP!)
Jebby
You will spend a little more outright, but end up with an aluminum head that flat out works and standard components are compatable (Intake, rockers, coolant bypass hole).
I have a problem with the 8 bolt intake hold down as well.......it just doesn't sit well with me on an aftermarket carb style intake (Which GM never offered).
Anyway...that is my opinion on it and if it were my money, buy a part of Dart 180's (NOT SHP!)
Jebby
Dr. Detroit
Joined: Mar 2012
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From: New Braunfels Texas
Me personally....no, unless somebody wanted me to do it for them.
Jebby
Racer
Joined: Jun 2017
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Jeez, not one person in favor of vortecs?!
If you get them from a junk yard for cheap and are willing to do some cutting on the valve guides it can make for a good project.
I wouldn't buy them new or refurbished from anywhere though. Just not worth the price.
I wouldn't buy a used pair for more than $200-250.
It's not stock, but I think there is something to be said about keeping the engine with GM parts, when possible.
If you get them from a junk yard for cheap and are willing to do some cutting on the valve guides it can make for a good project.
I wouldn't buy them new or refurbished from anywhere though. Just not worth the price.
I wouldn't buy a used pair for more than $200-250.
It's not stock, but I think there is something to be said about keeping the engine with GM parts, when possible.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Jeez, not one person in favor of vortecs?!
If you get them from a junk yard for cheap and are willing to do some cutting on the valve guides it can make for a good project.
I wouldn't buy them new or refurbished from anywhere though. Just not worth the price.
I wouldn't buy a used pair for more than $200-250.
It's not stock, but I think there is something to be said about keeping the engine with GM parts, when possible.
If you get them from a junk yard for cheap and are willing to do some cutting on the valve guides it can make for a good project.
I wouldn't buy them new or refurbished from anywhere though. Just not worth the price.
I wouldn't buy a used pair for more than $200-250.
It's not stock, but I think there is something to be said about keeping the engine with GM parts, when possible.
Vortec heads are what they are and of the 200 or so small blocks I have built in my life, exactly one had Vortec heads....and that was because it was a 96 1500 pickup....and it ran VERY well.....but too much going on there to mess with them for a serious high performance build.
Jebby
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Verdad Gallardo
Team Owner
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From: altered state
St. Jude Donor '05
by the time you magnaflux them and fix everything (remember most are over 20 yrs old I say its not worth messing with used ones.
What if they are like many cracked? There goes purchase and machine shop $.
id find out who makes summits if they come from overseas you may want to rethink that purchase.
Unless you can correct the problems its not worth it. I just poured well over 20 hrs (+parts)in a set that is now decent....if Ihad to pay somoene hell no.
only usa made stuff goes on mine anyways but its your car.
What if they are like many cracked? There goes purchase and machine shop $.
id find out who makes summits if they come from overseas you may want to rethink that purchase.
Unless you can correct the problems its not worth it. I just poured well over 20 hrs (+parts)in a set that is now decent....if Ihad to pay somoene hell no.
only usa made stuff goes on mine anyways but its your car.
Last edited by cv67; Sep 9, 2019 at 04:36 PM.
Le Mans Master
Joined: Sep 2001
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From: Unreconstructed, South Carolina
Eq ch350ha
by the time you magnaflux them and fix everything (remember most are over 20 yrs old I say its not worth messing with used ones.
What if they are like many cracked? There goes purchase and machine shop $.
id find out who makes summits if they come from overseas you may want to rethink that purchase.
Unless you can correct the problems its not worth it. I just poured well over 20 hrs (+parts)in a set that is now decent....if Ihad to pay somoene hell no.
only usa made stuff goes on mine anyways but its your car.
What if they are like many cracked? There goes purchase and machine shop $.
id find out who makes summits if they come from overseas you may want to rethink that purchase.
Unless you can correct the problems its not worth it. I just poured well over 20 hrs (+parts)in a set that is now decent....if Ihad to pay somoene hell no.
only usa made stuff goes on mine anyways but its your car.
OP alan600
however, there are NEW heads like a vortec but don't require a special intake/parts
brand new pair assembled $818 delivered ... Fastburn chambers ... fits OE-type intake ... easy + .500" lift valvetrain ... Vizard likes these
EngineQuest CH350HA ... country of origin New Zealand ... includes screw in rocker studs & headbolt set ... fits perimeter or centerbolt VCs
https://www.ebay.com/itm/Chevrolet-3...oAAOSw7ThUkH4f
https://www.aamidwest.com/enginequest/eq-catalog/
more specs & flowchart in their catalog
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
That ebay head: ^^^^^^^^^^^^
Just my opinion but, I don't want anything to do with "Self-Aligning-Rockers".
Also states that if "guide plates" are used you must use a .125 longer pushrod.
So both of these options will add to final costs considerably. As in $250-$300 or more.
Just my opinion but, I don't want anything to do with "Self-Aligning-Rockers".
Also states that if "guide plates" are used you must use a .125 longer pushrod.
So both of these options will add to final costs considerably. As in $250-$300 or more.
Last edited by HeadsU.P.; Sep 10, 2019 at 07:06 PM.
Le Mans Master
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From: Unreconstructed, South Carolina
Guideplates are about 0.125" thick
Anytime guideplates are added to motor that had none before ... the plates raise the rocker stud up about 1/8" ... that usually raises RA Fulcrum up about 1/8" ...
... and that changes RA geometry ... expect to lengthen PR to correct that geometry ... probably lengthen about plate thickness.
Anytime changing types of heads, cam, rockers, valvetrain ... plan there may need for different length PRs in order to optimize RA geometry ... just sop of building motors.
suppose some guys don't worry about RA geometry so all that wouldn't matter anyway.
Anytime guideplates are added to motor that had none before ... the plates raise the rocker stud up about 1/8" ... that usually raises RA Fulcrum up about 1/8" ...
... and that changes RA geometry ... expect to lengthen PR to correct that geometry ... probably lengthen about plate thickness.
Anytime changing types of heads, cam, rockers, valvetrain ... plan there may need for different length PRs in order to optimize RA geometry ... just sop of building motors.
suppose some guys don't worry about RA geometry so all that wouldn't matter anyway.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
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From: New Braunfels Texas
Having or not having a guide plate make zero difference on pushrod length......how could it?
Now checking pushrod length is SOP on a high performance build.....and correct geometry is important.....but stock SBC from 1955 to 1986 had 7.800 pushrods, guideplate or not. A factory Vortec would be somewhere in the 7.300-7.350 area due to the roller lifter....but this is irrelevant.
The rocker is adjustable.....it slides upon the stud up or down depending on adjustment.....as long as the rocker ball/trunion is not bottoming out on the stud flange at the bottom, adding a guide plate moves the stud up 1/8" which does nothing to the rocker....the stud just slides 1/8" higher through the rocker ball or trunion.
The only time a guideplate would change pushrod length is if the valvetrain is not adjustable....(Like a 502).
And yes....anytime you change cylinder heads and or spring package/valve lengths, you MUST check geometry.
It is amazing how much misinformation there is on small blocks....and reading this today makes me flat out upset......
Jebby
Now checking pushrod length is SOP on a high performance build.....and correct geometry is important.....but stock SBC from 1955 to 1986 had 7.800 pushrods, guideplate or not. A factory Vortec would be somewhere in the 7.300-7.350 area due to the roller lifter....but this is irrelevant.
The rocker is adjustable.....it slides upon the stud up or down depending on adjustment.....as long as the rocker ball/trunion is not bottoming out on the stud flange at the bottom, adding a guide plate moves the stud up 1/8" which does nothing to the rocker....the stud just slides 1/8" higher through the rocker ball or trunion.
The only time a guideplate would change pushrod length is if the valvetrain is not adjustable....(Like a 502).
And yes....anytime you change cylinder heads and or spring package/valve lengths, you MUST check geometry.
It is amazing how much misinformation there is on small blocks....and reading this today makes me flat out upset......
Jebby
Last edited by Jebbysan; Sep 10, 2019 at 07:05 PM.
Le Mans Master
Joined: Sep 2001
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From: Unreconstructed, South Carolina
But most rocker studs are tapered ... and the fulcrums can bottom out ... and some do ... if the PR is not longer to get the fulcrtum up & away from taper.
-edit-
should have specified ... most Aftermarket studs ... must of those are tapered as they're intended roller trunnions
m of ost the OE studs I've seen are Not tapered and intended for ball-pivot stamped rockers
-edit-
should have specified ... most Aftermarket studs ... must of those are tapered as they're intended roller trunnions
m of ost the OE studs I've seen are Not tapered and intended for ball-pivot stamped rockers
Last edited by jackson; Sep 10, 2019 at 07:14 PM.
Le Mans Master
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From: Cool Northern Michigan
Well, I guess its no different than buying aluminum heads. The instructions state that: it is imperative to check the NEW pushrod length before setting valvelash.
I always figured the aluminum heads had a higher rocker stud pad because I had to buy new, longer rods.
The head manufacturer goes on to say that in most cases a pushrod of +0.100 longer than stock is needed. (double check w/ pushrod length checker)
So! Which is it? Higher rocker stud pad, casted
or
the Guide Plate raises the stud.
I would be willing to bet, that if for some reason a person did not want guide plates anymore, torqued the rocker studs down flush, it would change the geometry.
I always figured the aluminum heads had a higher rocker stud pad because I had to buy new, longer rods.
The head manufacturer goes on to say that in most cases a pushrod of +0.100 longer than stock is needed. (double check w/ pushrod length checker)
So! Which is it? Higher rocker stud pad, casted
or
the Guide Plate raises the stud.
I would be willing to bet, that if for some reason a person did not want guide plates anymore, torqued the rocker studs down flush, it would change the geometry.
Last edited by HeadsU.P.; Sep 10, 2019 at 07:27 PM.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
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From: New Braunfels Texas
On an aftermarket head it is only valve length ....because of the +.100 valves put in a lot of aftermarket heads.....BUT....on a STOCK head....adding a guideplate does not require a longer pushrod....if that was the case all LT-1’s and L-79’s would have a longer pushrod and they do not....
Dart Pro 1’s are considered a stock replacement head and in the tech sheet....if running 1.250/1.437 springs (flat tappet or hydraulic roller) the valve length is stock....(although they urge you to measure).
Sportsman II’s and S/R Torquers have guideplate and are able to run a stock length pushrod....
If you get the 1.550 Roller spring package.....it increases .100
My own flat tappet 406 with Dart heads came in at 7.850....+.050....but I suspect that this is due to the pocket in the Comp rollers and the fact that I believe that 7.850 is a better stock length....(the L-79 in the Avatar has 7.850’s as well with factory 461 heads and Crane rollers)......both engines were Prussian blued and rolled over to check geometry.
Jebby
Jebby
Dart Pro 1’s are considered a stock replacement head and in the tech sheet....if running 1.250/1.437 springs (flat tappet or hydraulic roller) the valve length is stock....(although they urge you to measure).
Sportsman II’s and S/R Torquers have guideplate and are able to run a stock length pushrod....
If you get the 1.550 Roller spring package.....it increases .100
My own flat tappet 406 with Dart heads came in at 7.850....+.050....but I suspect that this is due to the pocket in the Comp rollers and the fact that I believe that 7.850 is a better stock length....(the L-79 in the Avatar has 7.850’s as well with factory 461 heads and Crane rollers)......both engines were Prussian blued and rolled over to check geometry.
Jebby
Jebby
Last edited by Jebbysan; Sep 10, 2019 at 08:05 PM.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
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From: New Braunfels Texas