skinny z

Still waiting to see the heads. Machine work, springs...all unknown at this time.

I agree on measuring. I will say that part of the limitation on Vortecs is the short installed spring height of 1.7". With a swap to a spring of a different spec with an installed height of 1.8", you've more or less picked up a tenth in lift capability (all else being equal).
Still,when making any changes over stock, you MUST measure or you end up with stuff that looks like these pictures.
That's the result of buying Dart Pro 1 heads from a reseller who sold the heads and cam as a package. What the builder (my friend) didn't do was check for coil bind. The reseller had swapped out the mid spec spring from the Darts (Comp 987) and used the lowest spec spring with the before mentioned shorter installed height. Max .470" lift for the spring and retainer combination and a cam with .495" (on the exhaust) dosen't work well for very long.

3rdgenmaro

iTrader: (9)

Yep. I speak from experience too. I assumed the machine shop new what they were doing when I told them what cam I was running. The valve springs they installed they never checked coil bind. Needless to say excessive pressure on a flat tappet cam will round off the lobes.

With my vortec heads, ls6 springs, comp retainers, I measured 0.54x" seal to retainer. (not factory seals)

Do it right the first time and never worry again. I finally learned that after screwing myself over by not listening to others! Young and dumb. Guess Im finally starting to grow out of it.

skinny z

That's interesting. I'm using the Comp 26918 spring and matching retainers. There's room to spare with .544" lift.
I thought that the LS6 spring was more or less a direct replacement for the Comp spring.
It is documented that the Comp Beehive (can't speak for the LS spring) will work with no machining and lift capability increases by about a .100".

And for the op, the first go around with my Vortecs was .454" lift flat tappet. Box stock heads. Next was a 1.6 ratio rocker upgrade that included the 26918 springs, enlarging the pushrod holes, screw in studs and guide plates. The guides were cut for Viton seals however I can't say what additional clearence was created if any. The 3rd version using the same heads was a hydraulic roller with .544" lift.

InfernalVortex

iTrader: (4)

http://www.alexsparts.com/products/V...AT-TAPPET.html

http://www.alexsparts.com/valve-spri...rf-hyd-roller/

They're mystery parts from a guy named Alex. They seem legitimate enough and there's a few out there who use his parts, but if I could swing it going the beehive route feels a little better to my gut since I would be using genuine GM springs. But I havent decided which way I will go when it comes down to it.


Something is off in your setup, I dont know what it is, but if thats truly your clearance it would mean your heads, stock, have something like .400 retainer to guide clearance, probably less, if that's what you have WITH beehives/beehive retainers and shorter valve seals.

If I were you I would find the discrepancy. I'm running a .470 lift cam on regular springs and stock Vortecs. If the beehive retainers are any shorter than waht I've got, i will in theory gain at least that much in retainer to guide clearance.

skinny z

Here's a catalog cut from Sallee Chevrolet regarding the stock Vortec spring.

Valvesprings: Single wire with damper 1.235” O.D., 0.875” I.D. 75-pound seat pressure @ 1.700” installed height Coil-bind @ 1.150”

Once you make the move to an beehive/conical spring two things happen. One is that the installed height increases from 1.7" to 1.8". That provides more guide to retainer clearence. The 2nd is the smaller retainer required for the conical spring. That provides even more clearence. Combined and you're well into .550+" with acceptable levels of room for both coil bind and guide/retainer.

3rdgenmaro

iTrader: (9)

Crap, sorry guys I fat fingerd the typing.

Was supposed to be .54x" clearance.

Besides, have you ever looked at the flow numbers for a stock vortec head? Flow doesnt increase (very slightly) above .500".

I made the decision to stick with 1.5s instead of the more common 1.6s on my setup. Simply because of the clearances. I know it would have worked, but it would have been too close for my liking. I would rather play it safe then worry about the little gain.

Danny515

It is absolutely possible to get 500= lift out of a vortec head with no machining. I know this because I'm running 525/525 now and the only machining done was the port/polish I did. The retainer used is a modified retainer which is a much lower profile than the stock ones, increasing the clearance. The beehive/LS6 style springs will handle more than 600 lift but its recommended to max it out at 550 on the vortec heads that have not been machined to avoid any further clearance issues. This is an old and tried method and works great in lift ranges of 475-525.

Here is the first link I found, but there are tons of right ups by magazines and threads. Thats how I first found out about them a couple years ago.
http://www.carcraft.com/techarticles...ade/index.html

Danny515

It is absolutely necessary no matter what anybody or any machine shop tell you, to check clearances. Ive had my fair share of impatient moments when ive tossed something in going off of what I was told and been wrong.
Infernal - we were talking about the Alex's parts the other day - that is the kit I am using now. I ran across it as a cheaper alternative to Comp or LS6 springs.
SO far Ive had no issues at all with them - I'm running 525/525 on mine and they seem to work great. Ive only had them on there for about 2 months, so its possible if they are lower quality that I could have issues in the future, but as of yet they are just fine. Not to mention less than half the cost of Comp. You just have to watch - because they have very similar looking sets that have different specs. I ordered a set that included springs,retainers, keepers and also ordered a set of viton seals and total including shipping was less than $125.

Danny515

And as far as clearances on the set I'm using here's the specs

110lbs @ 1.8'' installed ht
335lbs @ .550''
Coil bind 1.140
I measured mine at full open. Even being on the safe side of having a .090'' clearance between retainer/seal. I'm over that so won't have any issues with clearance.
So to run a 500 or 525 lift cam is no prob and gives plenty of extra clearance so you don't run into any coil bind or retainer clearance issues. If you are running a 480 or 500 lift cam you are plenty covered and won't have anything to worry about

3rdgenmaro

iTrader: (9)

I agree, the problem I had was that the way you worded it previously, someone could take it that you could get .550-.600" lift on vortecs with just springs and retainers.

That is what I was referring too.

Danny515

You can get 550 on just springs and retainers. Anything over that I would start to get weary. WIth a 550 lift, its estimated that you give yourself the add'l .090'' clearance between retainer and seal. Some guys say they run with only .050 clearance and its fine - I am not so daring. but in those cases with only a spring and retainer swap you would end up closer to a 580-590 lift. It can be done, but to squeeze clearances that tight is asking for trouble.
Not to mention like u said, the vortecs arent going to give you the same results over 500. Their design gives them great low flow numbers, not necessarily great high flow numbers. Ive run a few heads that are definitely more qualified in the upper rpm's but generally speaking, street cars and daily drivers are gonna spend most of their lives under 5k or 5500 which is why these work so well. And more importantly, if you do the cleaning and springs etc yourself, you can have a nicely set up pair a hell of alot cheaper than a set of AFR's or Dart, and nowadays for me thats the name of the game - gotta do it cheap or not at all. If money wasnt the issue, I would have a ridiculous flowing set of aluminums.

midge54

this alex kit doesnt seem like a bad thing either, if it will work, about the same price as the cam/lifter kit im looking at that has a 465 lift, which again comes back to the question, which is better suited for my driving desires, the 510 lift which is in the motor or the 465 lift cam

midge54

oh and the pistons that are in this motor are silv-o-lite keith black pistons. Picked this motor up tonight and it is clean as a whistle in side, no marks anywhere, be lucky if this thing has 4,000 miles

Danny515

Sounds like you're in good shape. As long as you make sure to clean up all your mating surfaces and get a good seal on all your gaskets you're golden.

As far as the cam, the lift figure won't play into it as much as the duration figures. More lift is always better, but depends if it is under the same duration or if you need to go with a long duration in order to achieve that lift.

midge54

So pulled the cam at lunch today it is a comp cam 292 501/501 any thoughts

3rdgenmaro

iTrader: (9)

244/244 @.050

2,500-6,500

110 LSA

Depends on what you want to do with it. It aint on the small side, but it isnt huge.

midge54

Just a driver I don't want to change converters and I want decent low to mid range power

86LG4Bird

iTrader: (1)

That IS HUGE for a 355! It certainly has no place in the setup you've described.

midge54

I called summit they suggested either the comp cam part number ccacl122382 or the summit 1103 I originally picked out

86LG4Bird

iTrader: (1)

That Summit 1103 looks good for your application. No idea what that Comp number means ??

midge54

http://m.summitracing.com/parts/CCA-CL12-238-2

3rdgenmaro

iTrader: (9)

I wouldnt go that far.


If you arent going to swap converters then you definately dont want that cam. Of the two you listed, I would go with the comp.

86LG4Bird

iTrader: (1)

The Comp CCA-CL12-238-2 looks stronger. Quicker lobes, more low and midrange torque.

86LG4Bird

iTrader: (1)

Yeah, no matter what converter you put behind it, that 244/244 cam will never make useable power in his setup. His heads are not a good match for it and the CR would have to be so high to make it work at all. A smaller cam will beat it in all respects.

midge54

I think I'm going to go with the summit 1103 just to have a lil extra clearence in the valves since summit told me not to use more that 475 lift

midge54

My vortecs showed up they are 062 heads

3rdgenmaro

iTrader: (9)

Before you order a cam, check the clearance you have. You may have more then you think. The comp cam will be better then the summit one.

Danny515

Well like we covered before, depending on what, if anything you do to the heads, will determine your safe lift range. If you do the mods to accommodate more lift then dont worry about the 475 recommendation, you will be fine. I would agree with the rest of the guys, that for how you are set up and what you are looking to get out of it, that 244 cam is too much.
You are on the right track with the comp, because with the vortec heads it benefits you to have a bit more duration and lift on the exhaust side, and the Lunati 60102 would also be a good fit for what you are trying to do. Ive used that one and with the 112 LSA it has very good street manners for a daily driver. I don't know off the top of my head, but i know whenever Ive looked at cams, Lunati is generally more affordable than comp. THe 60102 will give you slightly more lift also - but only if the heads will be set up for it.

midge54

im thinking it may be in my best interest to replace the springs in the heads to allow for more lift clearence, even if im not close. Im still thinking of going with the summit 1103 basically because my budget is running slim. now can i just order the springs and use the factory retainers or should i order the alex parts drop in set

midge54

http://www.summitracing.com/parts/SUM-174001/ will this kit help with lift on the summit 1103 camshaft kit

Danny515

If you order the springs from Alex's, you order the kit with the lower profile retainers. THat way you are more than safe and an easy way to get a bit more flow later is to just upgrade to the 1.6 rockers.

And to help you think ahead a bit, if you are eventually going to upgrade to 1.6 rockers, the heads need to be set up accordingly. Even if you go with a self aligning 1.6, which you probably won't, you still at the very least have the drill out the pushrod hole in the head to a 1 inch hole to avoid pushrod interference. You can do this yourself before you bolt the heads on just so you don't have to mess with it later.

If you are going to go to a non self aligning rocker - you have to install guideplates and drill out that hole.

Just in case you wanted to think about it before the heads go on

midge54

there is a lot of decisions on this build, since its my first, but i dont plan on upgrading to 1.6 rockers, however i think i am going to order that alex parts kit and the comp cam set that summit suggested that i posted earlier, now i saw there is also a shim kit by alex parts, do i have to shim the springs along with the low pro retainers and the springs?

Danny515

Once you get the springs, install one set of valves and measure your installed height. I could be wrong (which is why you always have to check for yourself) but I'm thinking your height should be pretty close to requirements. Plus, the springs I got were recommended at a 1.8'' installed height. I would think you should be somewehre around a 1.79-1.8. And since you're not running a really high lift you have the extra room as far as clearances are concerned.

midge54

do you think im on the right track with the comp cam, the spring kit for my motor setup

Danny515

Yeah, my opinion, you will be happy with that setup, it will perform well as a daily driver, and since alot of the time it will be in the idle-4000 range, you will get good response from it. And down the road you can always upgrade as you see fit. My thoughts are when you're doing a build the most important thing to consider is what you realistically are going to do with the car, and how the car will be used most often, and no doubt your budget. And I think for what you are going to use the car for you will be in good shape.
I' m sure it won't be long before you get the fever just like the rest of us and spent countless hours thinking about about what other mods you are going to do, but thats later. Be sure to take the time to assemble correctly, dial in your fuel and timing correctly, and you're set.
My first build was taking a 305 with over 150k out of my 81 Malibu and putting in a 350. THe 350 was nothing special and barely minor upgrades over stock. My father in law is a 25+ yr GM mechanic and couldve helped me build a monster but I didnt have the money. Needless to say I might have been lucky and gotten that 350 in the 280hp range, but it was still a great feeling to have built my own motor, and even though I wasnt the fastest on the street I had a blast with that thing.

midge54

Thanks you all have been a lot of help I already placed the order through summit for my cam set, intake bolts, gasket set, and carb adapter along with my spring set from Alex parts so I think it's only a matter of cleaning the heads and block up and getting everything assembled

Danny515

Good deal. et all that stuff cleaned up real good and take your time getting everything together and making sure everything seals and is torqued right and you will be up and running in no time. Let us know how its going

skinny z

Has ANYBODY worked out compression ratio? Lots of cam choices being tossed about but no mention of any calculations.
I think it would be smart to measure the piston below deck value (especially since the heads are off). Take that, find out what the KB piston has for valve reliefs and start working out potential static compression ratios. You can work head gasket thicknesses into the equation as well as optimal quench (if it's possible).
As was pointed out much earlier, your cam choice is tied directly to your compression ratio.
Any informed decision must be based on that.

Edit. Midge. I just read your last postf. You've ordered a cam?

midge54

yea i ordered the cam that summit recommended after giving them all my information

Danny515

Yeah I thougjt about that during earlier posts. He said it was stock deck ht, and will end up with a gasket somewhere around .039-041, which with those pistons will put him in the low 9's - maybe mid 9's max. without shaving the heads or deck there won't be major increases. And quench will be what it is, and wont really be able to be adjusted because he wont want to adjust deck or shave heads, because as a daily driver he wont want to raise the comp at all. I genetally prefer a bit bigger cam, but that selection is a safe and definitely within reason for a driver with those specs

midge54

really with flat top pistons it will only measure about 9-9.5:1 compression ratio, thought for sure it would be up at around 10:1

skinny z

The lower the compression, the shorter the cam (less duration and most usually lift).
Most OEM blocks go something like this.
4.030" bore
Deck height .025" (often more)
64cc heads (Vortec typical)
The variable here is the KB piston. Flat tops assume 6cc valve relief.
Combine that with a .025" gasket (4.100" bore typical).
That's 10:1.
The thinner head gasket helps to optimize quench and will give some resistance to detonation.
A .039" gasket dials back the SCR to 9.7:1.
It would be nice to know the actual relief volume of the piston.
What are the specs on the cam? Duration at .050" and advertised?

midge54

Basic Operating RPM Range 1,300-5,600
Intake Duration at 050 inch Lift 218
Exhaust Duration at 050 inch Lift 224
Duration at 050 inch Lift 218 int./224 exh.
Advertised Intake Duration 262
Advertised Exhaust Duration 270
Advertised Duration 262 int./270 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.462 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.469 in.
Valve Lift with Factory Rocker Arm Ratio 0.462 int./0.469 exh.
Lobe Separation (degrees) 110

skinny z

Calculating dynamic compression based on the advertised specs of the cam (without knowing the intake centerline angle [ICL]) and our theoretical SCR (using a thin head gasket and 10:1 SCR) , you end up with anywhere from 8.2 to 8.4:1 DCR.
The link to the article posted earlier lists the limits of DCR in street and race engines.
Provided you can keep detonation under control, that combination should build plenty of low engine speed torque. The thicker .039" gasket brings the DCR down to as little as 7.9:1 depending on how much advance is built into the cam (ICL).
There are still some variables to work out to help zero in on your last chance for some change that being your choice of head gasket.
I've always measured the piston below deck height and had the specs for the pistons. You will also need to find the ICL of the cam. I would like to calculate the valve overlap.
More data means better results.
So far so good though. That earlier 292 cam would have been a disappointment. (Don't throw it away though).

Danny515

Based on a rough .025 piston-deck clearance which is what im guessing should be close- I dont have the calculator in front of me but im sure he will top out in the mid 9's. No reason to start thinning out head gasket to get closer or above 10 right now, this is gonna be his daily driver. With cast heads, and having to sit in traffic, pay for gas more often since hes driving it every day, etc. if he sits in the mid 9's he should be more than happy with it. A slightly higher 110 lsa, and the bit of addl duration on the exhaust to help those heads- he will definitely enjoy it and be more than streetable. Once he gets into more performance - converter, engine mods, etc etc, adjusting head gasket cc and compression and on down the line can be re evaluated once he has the experience of gettinf his firat motor together. Especially when building your firat, and on anything of a budget, theres nothing wrong with the few horses you will leave on the table. I take much more time going through mine, but I am looking for more of a strip car and a 3500lb car at that. I think the setup will work great for what he wants to get out of it and will respond very well as a daily

midge54

Actually this isn't going to be my daily driver, that is what my 2011 turbo sonata is for however I do want a car that is street able yet fun to drive

InfernalVortex

iTrader: (4)

Ive got pretty much the build you're talking about. I recognize that cam as the comp xe262 and I've done the DCR calculations on it and know all the specs and have done the math. BTW if you want to compute the DCR, it has a 106 ICL, 110 LSA, 262/270 duration. You can figure out the DCR easily from that. it's a much better cam than any "Summit brand" or edelbroke flat tappet cam. And it's definitely not a bad choice.... but...

.030 over 350
.039 gasket
.025 in the hole pistons (stock deck with 1.560 pin height piston)
Vortec 64cc heads
flat tops with valve reliefs for 5 more cc's of chamber volume.
Comp Xe262 cam (218/224, .462/.469 ish lift if i recall)
9.8:1 compression, terrible quench (.064, like yours probably will be), and an 8.4:1 DCR.

The only difference from my car to yours is the cc's given by the piston, and that cant be more than a couple of cc's off in either direction from mine.

This car has a torque curve from hell. It will pull hard from about 1250 RPMs and it keeps pulling to right about 5500-5600. The advertised power band is right on. It's attached to a T56 so you can feel that torque all the way through. It's a REAL good, drivable street cam that makes decent power.

Now with all that said... what you really want to know is what would I do differently if I could do it all over again knowing what i know now?

1. I'd go with some thinner head gaskets and pay more attention to quench. The higher compression ratio is fine because the quench distance reduces tendency for detonation. http://forum.grumpysperformance.com/ has a lot of great post, and grumpy links to them often here in these types of threads. Compression is, as I understand it, always good as long as you dont detonate. It increases efficiency and power and in the process of that, it allows you to run a larger cam and maintain a reasonable DCR in the correct range. The problem is when the DCR is too high (high compression, small cam, or very high compression, medium cam, etc) and you run into detonation issues. Match the compression to the cam. But the problem is you dont want to use the headgasket to do that. you use the pistons to control compression. The quench distance should ideally be viewed as a static constraint, and work everything else around that. So go ahead and run 10.2:1 SCR. If you run a cam that gets you an 8.25 or lower DCR, you'll have no issues running pump gas, ESPECIALLY with vortecs and even more especially with a good .040-.044 quench distance.

2. I'd go with a bigger cam. The DCR for this cam and these heads is just really borderline if you ask me. It's pretty high. That said, I think that's a big part of why this thing makes SO much power and torque over such a huge range. It's a VERY responsive engine. I chose the cam I did because when I built the engine I had a stock stall 700r4 and a 2.73 10-bolt. I now have a T56 and a 3.70 rear gear, so I can get away with a much larger cam. But I will tell you that it had no problem cruising around with the automatic and highway gears when it was in the car. If you need something that can handle awful gears and not much give in the trans (stock stall or manual) then the xe262 will pull the car as hard as you'll ever need it to. I'd go with an xe268 if you can figure out a way to put decent gears in the car. I think that cam is a little better suited for the compression ratio and the heads than the 262 is. Just keep the DCR between 7.75-8.25. For the record, the Comp XE line makes more dynamic compression than the older cams, like the 280h due their shorter total duration. So you may need to go a little larger on the cam, but due to the higher static and dynamic compression ratio your low end torque wont tank like you might think. I wouldn't go past something in the 235/235 at .050 range though. Crunch the DCR numbers with the Lunati 60103 and xe274 cams. And also check out some of the howards cams, I've been looking at this one... 112141-12 . They've got some interesting cams in that range and slightly smaller on their site that look every bit as good as some of the cams from Comp and Lunati.

3. I'd get the valve guides machined down and the spring seats set up properly to get rid of the stupid lift limitation these heads have. That was the other half of the reason I got this cam.

I'd gladly trade some of the brutal torque I have for some high end horsepower. The car, in 3550 lb raceweight trapped at 102mph. That's roughly 280-300 hp. Thats good for a budget 350 build, but a bigger cam doesnt cost any more, and I could have run a thinner head gasket and an xe274 and probably made 340-350hp, and that's what I wish I had done. BTW, under ideal conditions with the power Im making, the car is allegedly theoretically able to go 13.2 at this weight(Very average for a third gen w driver). That's assuming perfect shifting, perfect launch, slicks, etc. It'd probably do pretty close to that with a properly stalled auto and the right tires/suspension. It's a mid 13 second car as it sits.

So do you want a racecar that's FAST? Or do you want a really fun driver's car with a very practical, torquey power curve that is respectable on a track, but not great? I think with a 230/230 ish cam it could probably run into the 12's... wouldnt be quite as easy to drive around town, but I think it would still be more than tolerable.

I have another vehicle for a daily driver. The Camaro is the toy car. I'd prefer to trade off some practicality for some horsepower, that may not be the right choice for you. Im actually thinking lately that perhaps the super torquey cam I have will be better for the autocross stuff I really want to do.


And just in case you're interested in how that cam sounds, here's what it sounds like with Long tubes that Y into a single 3.5 inch exhaust.

http://www.youtube.com/watch?v=NZl1_P1VqOo


Your proposed build is almost an exact copy of mine, so if you have any questions just ask. It's definitely a LOT of fun. But after 3 years of driving it, I want more.

midge54

I have 373 gears factory in this car with4 wheel disk so I have decent gears. This will prob never see the track just cruise the streets on nice days the only time it might be tracked is my buddy wants to run his 00 v6 mustang versus my trans am so I told him only on the track

midge54

What pump gas do you run in yours infernal, 92?

skinny z

Infernal has some accurate data and information.
I'd also like to know what he uses for fuel. With that high a DCR and the less than optimum quench puts him at risk for detonation but he'd know it if it were a problem.
I have the same basic setup as well however I'm running a hydraulic roller with 276/282 duration and the DCR falls in around 8.1 or so with the SCR right at 10:1. Premium fuel is needed although if I backed out some of my initial timing from 16 BTDC, then I could get by with a midgrade fuel.
For the record this 3750 lb combo runs 12.7 @ 108 and still knocks down 22+mpg hiway with a 670 vac secondary carb.
Like we've said, as an affordable entry level head, the Vortecs are unmatched. How you build around them is up to you.