So what's going to be your choice of lifter? Do you intend to use the OEMs?

 

I've never used OEM roller lifters myself…but are you referring to something like this happening?
Depending on what you read about using them on an all-out, high lift, high rpm application…they might not be optimal...

 

I'm reading this and thinking a suggested failure like this is simply a result of losing control of the valvetrain, ie. revving higher than the parts can handle.
I think as soon as you open a gap anywhere in the lobe-lifter-pushrod-rocker-valve link, it's inevitable you're going to beat the crap out of some parts!
Am I oversimplifying this?
I'm spinning to 7100 for hundreds of dragstrip passes over 4 seasons with a HR .617 lift cam and the factory dogbone/spider arrangement. I DO run some fairly stout beehive springs, ~160 lbs on the seat, and .080" wall pushrods.

 

Revving higher than the parts can handle is exactly right.
The knock on the OEM lifter (not the spider arangement itself) as I hear it is that at high rpm, 6000+, the lifter body distorts, then the lifter collapses resulting in component seperation and then it's anyone guess. Might survive it forever and put it down to valve springs when the engine lays down on the top end. Or it beats the crap out all your hardware like happend to us. After I had heard about this deal with the OEM stuff, true or otherwise, a change to Comps (then) new short travel lifter solved the problem with no other changes made. Picked up substaintially in mph.
It's how that gap in the valve train gets started is what had to be controlled. The components in this engine were top notch parts. Comp Beehive springs, tool steel retainers, etc. The only thing original were the lifters and they were new. In my case, it was the lifter not being able to hold up.
Just an observation.

 

Forgot to add, I run stock LT1 lifters. 1/8 turn past zero lash.

 

I wish I could say the same.
Maybe you're leaving something on the table?

 

skinny, how much spring pressure were you running with the stock lifters? possibly not enough and opening that dreaded gap?
I'm having trouble with that theory of distorting the lifter body.......unless you were running some ungodly springs ??
Regardless, I see no reason for the OP to be afraid of running GM lifters since he's said "..target a 58-6000 red line". That's child's play even if running something like XFI lobes. I've seen more problems with Comp "R" lifters than with stock GM (although I suspect user error in a couple of those cases ). I know there are better/more expensive ones available than those "R"s; I just don't think it's money wisely spent in his case.

 

Not to risk copying anything from another site...

But from what I've read, it seems it not only could be caused by loss of valve train control at upper RPM's, but also due to use of OEM enclosed roller lifters with the spider on high lift cams where aggressive cam lobe profiles and additional lift is created.... on some cams.... by reducing the base circle height....which causes the lifter to travel too far into the lifter bore...which in turn causes the dog bone to come off the lifter.

I would imagine if you purposely had a cam cut on a small base circle, the same may apply. That's why I thought Skinny was asking about using OEM roller lifters with the spider.

Also, since the OP is talking about a stroker 400, it very well might apply here...I even run a cam with a small base circle to ensure I have plenty of clearance for the aftermarket rod bolts.....but I probably don't absolutely need a small base circle cam...

.....at least that's the way I understand it....

 

Comp 26918 springs. 125 @ 1.80, 372 lbs/in, 367 @ 1.15. More than enough to handle a little XR282HR cam (since changed to an XR276HR custom grind). Buzzed to 7000rpm (on the 1-2 shift). We were at our wit's end trying to find out what was wrong with this thing. After reading the article on the lifter distortion, it made too much sense not to try it. It worked. I found it interesting that most build dyno sheets I've come across with an OEM lifter have peak power in and around 5500-5700 rpm with hp dropping off acutely beyond 6000 or so.
That said, at 420+ cid and a red-line of less than 6000, perhaps the OP won't have any problems. There IS reason why there are many race orientated hydraulic rollers though.
You make an interesting comment about the XFI lobes. What's your experience with them? I'm running a custom cam with XFI lobes and I can tell you that if you're not spot on with the valve train geometry, you'll be visiting the machine shop soon enough for valve guide repair. Still, my lobes with .570" lift and 282adv/224 @ .050" isn't nearly as aggresive as some.

 

Great input. I am referring to OEM style lifters with the dog bone/spider combo. Planning to run comp cams components and they are less expensive than the retros. I'm also planning to use the XFI lobe cams and they do seem aggressive. Hadn't considered there being issues with the style of lifter though. Seems dumb for dart to provide, advertise and basically brag about having provisions for OEM style lifter if they are inadequate.

 

Spun ls7's to 7000 in my oem dogbone setup. Ls7 lifters which are now gm replacement for all ls1 type motors are better constructed than older oem lifters. They have a stiffer internal spring for one and possibly different oil orifice hole sizing. That i am not sure but countless ls1 guys spin huge rpm with them. 7500 + has been done.

I ran 165-170 lb seat double springs with 412 over nose, comp magnum high lift type lobe .603/.613. Never floated. AFR 8mm valves help. Keep valves and valvespring components as light as you can for those aggressive cams. Xfi is aggressive but you can turn them high rpm. Too weak of spring like most other hyd rollers use will float over 5700.

I wouldnt run much over 170 lbs on a ls7 lifter tho, if you need that much pressure then go to the steel bodied Morels. They are a very tough lifter and can handle some light solid roller springs over 220 lbs seat 500's open. I run these on my heavy valved 2.100" turbo motor. 180 lbs seat, 450 open, it will handle a .640" hyd roller to 7200 rpm so far under 24 lbs boost. 3/8" pushrod, shaft rocker setup for best stability

 

I've had a hand in so many simple LT1 builds making great power beyond 6000 rpm with stock GM HR lifters, and just can't see them being the issue.
One thing in common though, we typically run more spring pressure than you mentioned, skinny. I'd never try to run those 918's to 7000, even with that XR cam. Not enough spring, IMO. The most I've used them for was something similar to a CC503 (224/230) cam limited to 6500 rpm. And for 7000 rpm, it's not just the springs. Pushrods, rocker studs all need to be beefed up; those parts will flex out of control no matter how light or how heavy the springs. I'm sure you had those covered, just making that point for anybody happening to read this.
If the engine has enough cam and head flow, a dyno sheet dropping off after 6000 is not an issue with GM lifters, I assure you. It's the other valvetrain parts, pure and simple. Barring any ignition issues of course!
My setup peaks at 6400 and holds power very well out to the 7000-7100 shift point (limit of the LT1 PCM).
I've never put an XFI cam in an engine of mine or any I've been involved with. The only people using them successfully that I know of, without tearing up valvetrains, are running them in mild builds, none running them to 6500 rpm on a regular basis. Every one I'm aware of that have tried them in higher rpm builds have failed; however, the information I got tells me they cheaped out on the valvetrain --not enough spring, not enough pushrod, stock 3/8 rockers studs, etc. One thing for sure: if you follow Comp's advice for required valvetrain, it won't be enough for the rpm the cam will want with a good set of cylinder heads and intake!
When I need something better than I can spec myself using something like Comp XE lobes, I call Phil Odom at Advanced Induction. The .617 lift 228/234 cam I'm running in my Impala is from him. Also some good results in recent years with Lloyd Elliott custom cams (since he dumped his previous self-professed cam guru!)

 

He may have been self professed but i have run 2 of his cams with great success lol and plan on a 3rd. If i am thinking of the same person. Lloyd used to use him then went to bullet i thought.

I like these magnum high lift lobes. They seem more stable than others in the same lift range, with slower seat ramps.

 

You're luckier than most. Or perhaps he's learned a few things over the past few years. He burnt his bridges with the LT1 crowd, sending out "4x4" cams to people that would make a couple of great dyno pulls before junking the valvetrain and heads.
Yeah, those high lift magnum lobes are nice. They make a lot of sense with good flowing cylinder heads and bigger cube motors where you don't have to micro-manage all the duration events to the nth degree to get acceptable street manners and emissions quality and still make decent power.

 

When I'm referring to the OEM lifter I'm not speaking of the spider/retainer assembly, just the lifter. I can't say if the LT1 lifter is the same as the Gen 1 offering. Certainly, it's different from the LS7 piece.
As for the success seen running the LT1 lifters to 7000 rpm, I can' comment other than "job well done". I wish mine had seen the same success. Seems the common theme there is LT1 so again, I have no direct experience.
As for Dart and their lifter spec, there's a difference between "OEM" and " OEM style". The spider and retainer arrangement take the cost of having to buy a link-bar style out of the equation.

 

Everytime i hear valvetrain issues from cams i have to question components and setup. Geometry is king and stability in valvetrain is also important. I learned the hardway last year when i suffered horrible float and wiped guides in less than 500 miles i just didnt have the rocker system correct with pushrod length. Now i went shaft rockers and geometry was much easier to setup correctly. So far so good.

 

My reasoning to run XFI lobes where along those lines. I wanted all the lift I could get while keeping duration within my SCR range and as short as possible while meeting my HP and RPM targets. Seemed XFI fit the bill.

 

Isn't that the truth!
Once the weather warms up (unheated shop) I'd like to start a thread documenting my valvetrain setup. While perhaps being a primer for newbies, maybe some of our own "gurus" will chime in with a critique.

 

Let's see if we can bring this thread back for the OP…..

I'll throw out my humble opinion here…and I may not have the racing experience that Orr, or 86LG has (I don't), but I'd spring for some good aftermarket lifters. Call Dart…ask them what they recommend.

To me, it doesn't make sense to spring for a nice aftermarket block and cut any corners on things like lifters, rockers and the like. Not saying you are - or intend to…

I do know the Little M block I have being built right now for instance - even my link bar rollers could come close to hitting the top of the lifter bores due to Dart's "raised" bores…I'm sure they don't raise them for the heck of it, and there's probably a benefit to do it…or else they wouldn't. I got lucky and mine cleared fine..

Thing is, even some retro-roller lifters have interference issues due to the raised lifter bores, and notches need to be cut for the link bars to clear…or get taller style lifters. That's just some of the things you run into…it's in the game..

 

I missed this post earlier (while I was typing the one below it )
It looks like we agree 100% on "GM" lifters being up to the task. I realize from skinny's post that some may have concluded from my remarks that I was advocating the use of old 1980's Gen1 roller lifters. Sorry about that. No, I've never explored their limits!
My reference base was the roller lifters that came in the 1992-2000 era LT1, LT4 and L31 (Vortec) engines, which are every bit as good as the LS7 lifters. Design-wise they're virtually identical, there's just been a QC issue with a batch or two of the LS7's. But overall they have a great rep, and I have no issue with using them. In fact, they're now GM standard stock for LTx and L31 replacements.

Edit: maybe I was too gracious with the "batch or two" remark on LS7 lifters. Here's what my buddy in Maryland, a respected LT1 builder, had to say about them:
"I try to use the original lifters and cringe when a customer sends me a pack of the new LS7 lifters to install in their motor. I have seen the LS7 lifters (right out of the box) have bad rollers. They take forever to pass oil up to the pushrod and sometime never pass oil.
The GMPP lifters in the lifter kit with dog-bones and spider seem to work 100%. But they cost 2 times as much.
Karl"

 

I do remember Comp cams offered a dog bone set-up that corrected the short comings of the GM OEM ones.Where they said the GM ones where limited to 5,500 and theirs would run a tad over 6,000 like 6,500.They did that to compliment the cams they offer.

Not for nothing Engine Builder magazine did a article about roller lifter failures in LSx engines and to narrow it down the 5.3 engines.Oddly enough shortly after reading that the shop repaired two that came in.

Now the way to get to a solid performance is hands down with a solid roller cam.If you use a shaft steel rocker set up like Jessel or T & D,you will find valve adjustments will be like once a yr.Not a "tinker's toy" like most think.

 

I know alot of guys using ls7 lifters and never had an issue. Have heard of failures with needle bearings but i am curious if that was anyway related to valvetrain issues, and spring rates used. Too little and suffering float? Beating up the lifters? Some ls cams are extremely aggressive.

With shp block it has raised lifter pads like all oem roller blocks. They require +.300 taller lifters. These sometimes may or may not install with the heads bolted to motor. My morels required me to remove heads to install lifters. Wasnt big deal since top end had to come off anyway, but certainly dont want to have to change lifters or cam some day and have to remove the heads again. Basically becomes an lsx

 

At least I know now that I'm not dillusional.
As I understand it, the old GM roller lifter had a cast body with machined surfaces. Any upgrade I've seen is a billet piece of tool steel. The Morel's are made this way as are Comps 15853 offerings. There previous 853, a mainstay in the retro roller market for decades has fallen on hard times. It's body is cast as well and the internet is full of people experiencing problems with them (Yes, I understand that many have been using them trouble-free). I had a long discussion with Comp regarding this. Ultimately they offered me a full refund on my used and broken lifters (kind of tells you something doesn't it?) which I promptly turned into a set of their short travel lifters. If I had known Morel was so economically priced, I would have gone that route. At any rate, lifters aren't an issue any longer for me.
For clarities sake, the 853 failure was one engine, a Vortec headed 353, while the OEM failure was a Brodix headed 355.

Here's a link to my letter to Comp. It's a bit of read but towards the end, the tech realizes that I'm legit and have genuine concerns with their products durability. Turns out I wasn't alone in that regard either.
Props to Comp for backing up their goods.

http://www.cpgnation.com/forum/used-...ters-6987.html

 

Ok my head is kinda spinning over the whole lifter issue. I am only referring to the style of lifter not who made it. I didn't realize that the style could have an impact on performance/durability. No, I don't intend to save $200 on an $8k build and have problems. If I need to "step up" to a better lifter I don't care what style it is. To me it seems the OEM type would have an advantage over the retros because it doesn't have to carry the weight of the link-bar and extra height of the body. But that's just me thinking, I did previously have a CompCams lifter problem but I attributed it to a galled rocker ball.

Also, I keep hearing about LS7 lifters and assume we're talking about GM made lifters not the application. Maybe I am wrong. Are LS7 lifters different than the Gen1 & LT stuff? I would expect CompCams would make their lifter to whatever spec they thought was best. If stepping up to their short travel or race lifter would be best please let me know.

Now to really open up a can of worms, I'm not dead set against a solid roller. It sure does sound like it would side step a lot of potential issues and it only takes like 2 min to remove the drivers side cover and maybe 15 on the passenger side. Heck I probably have the covers off twice a year anyway so throwing a feeler gauge in there is a no-brainer. Is this really the way to go? Cost/budget is always an issue and I strive to get good value but the solid vs hydraulic cost is minor.

 

Solid roller cam & lifters !

 

When people say ls7 lifters it basically now refers to gm made lifters for lsx motors. There used to be two part numbers and the later ls7 ones replaced the old and its now just labeled as gm hyd roller lifters. They are cheap at 115-135$ or so.

They are good lifters. I wouldnt worry about them

Solid roller seems overkill for what you want. They do not last anywhere near as long as a hyd roller lifter. A street solid roller profile will have good life as they arent as aggressive but still. Solids do not seem to last long in a street setup. My buddys car is abit more racey than your plan but his lifters failed after 5 years of mixed street strip driving, 5-7k miles worth of driving. Milder profile maybe go 10-15k. For 500-650$ lifters i'd just buy a link bar hyd and keep hyd roller. But i personally would not hesitate to use ls7 oem dogs on a typical .600" or less lift lobe that isnt revving over 6200 much and isnt as intense as the xfi type series and equals out there. Just my opinion

Street solid you may have to adjust lash 1 time a year. They usually dont need alot of work i just hear alot of engine builders describe the issues with trying to run them in a mostly street low rpm deal. Somethin that idles alot doesnt get oil to the lifters to keep them oiled and cool. But more race rollers have high spring loads. A street solid lobe uses more like heavy hyd roller type springs so they would last longer, just how much i am unsure

 

1st post of this thread says "street motor", and I'm in complete agreement with Orr89 that sticking with a non-exotic HR setup is the way to go.
And despite what I've posted about some issues with the LS7 lifters, you have no more chance of getting a bad one than you do getting a bad lifter from Comp. Just use due diligence and check them out thoroughly before assembling and firing the engine.

 

Soak em in some solvent to free up the gunk they pack the bearings with and then thoroughly lube them with oil. Dont need to soak them in oil but lube the bearings and roll the wheels. They come abit stiff out the box because they are gunked up i grease. Same with aftermarket ones. Inspect them and i'd say you are good to go.

If you are ordering the block send the lifters with block to machine shop to make sure lifter bores are clearanced properly.

 

I missed that part... for a "street car" stick with hyd. roller or a solid flat tappet if you want more RPM. You could also try Rhodes hyd. rollers; they are vari-duration design. behave like a hyd roller. but at RPM they perform like a solid. These lifters also let you run a "bigger" cam on the street because at low RPM they the bleed off duration, which, improves throttle response, increases vacuum, idle quality, and fuel economy.

http://www.rhoadslifters.com/Pages/Articles.html


solid roller lifters the weak link are the axle bearings which can fail in a street application, not enough oil at low RPM makes them prone to running hot and burning up the needle bearings. Not so much a problem on a track car, maybe every 5 seasons you get them rebuilt. (replace the roller, axle, & needle bearings)

I think if I were to put my car back on the "street" I would swap my solid rollers for the Rhoads hydraulic, that way I can keep the big cam and still have acceptable low RPM qualities you need in a street engine.

 

I have to agree here.

The problems I've seen locally with new GM HR lifters are in Gen III motors that the owner didn't replace the lifter guides which allowed the lifter to rotate a little and ruin both the cam and lifter.

On another note, I have ran a solid roller cam with CompCams Pro Magnum roller rockers and even though I check the valve lash once a month for the first year, I did not have to reset any of them.

 

Ok and in regard to the TYPE not BRAND of lifter for a hydraulic roller setup is anyone saying that a good-brand link bar roller is better than a good-brand dog bone (OEM style) roller?

Now in regard to each TYPE of lifter is there a specific brand or model I should use?

For example, GM lifters and Comp standard lifter may not be the best choice but the Comp short travel are better. And I would expect that not all retro fit lifters are "the best" just because they are connected via link bar. If one typ of control system has inherant problems Such as the dog bones wear or the link bar pins loosen up etc. Issues with the way it is made or specific brands or models within that brand is what I am interested in knowing.

I don't intend to knowingly put an inferior part in this engine just to save a dollar, conversly I'm not putting the "best of the best" in it either. A Callies crank and rods are an overkill for the intended use but the extra cost was minor and it's good insurance. The reason I started this build in the first place was due to valve train related problems most likely caused by cheap, mis-matched components poorly set up. I do not want to repeat that experiance if at all possible. The cost of the component is not the top consideration but I do have budget constraints so VALUE of the component is very important. That is really what started this thread. If cost were the only consideration I would have built the production 400 block. But in my case the SHP block was a good VALUE because of it's features and construction. Same evaluation process goes for lifters & valve train components. All else being equall, the OEM STYLE Comp cams lifters are less expensive than the Comp Retro-fit lifter so if there is no GOOD reason against using the OEM type then it is a better value and makes sense. Right???

 

Imo since you have a roller type block stick with oem style. To be honest the gm lifters are best bang for buck. So mass produced they can charge 130$ for a set. Comp and others can be 250-500$. I dont see a reason to do link bars and you run risk of them not fitting with heads on block, so if you ever decide to change cams or have to take apart, you have to remove heads for lifter change. That can be a pain and more $$$ for gaskets

Also note that only a few companies actually manufacture lifters. Rest buy them up and rebrand them as their own. Some 100$ more than others for same stuff. But the Morel performance lifters for 600$ are regarded as the best link bar style out. Its what i run in my car to 7200 rpm and no issues. I could go 7500 and it would work but i am scared of stressing the bottom end that high lol

If you've seen 160K mile motors you know the dogbones dont wear out. So thats no concern. I wouldnt recommend that setup if i didnt have the confidence that they would work. They were fantastic in my 7000 rpm 383 hsr. Good valvetrain setup, geometry, springs and studs will give life to the top end

 

Well until the big "lifter scare" I was just planning to buy the entire kit from Comp. If there is a preferance among the Comp pieces let me know. I'll go with their recommendations unless there is a reason otherwise.

My plan is to have them spec everything from crank sproket to valve with the expectation they will keep it all compatible. The only question was the valve springs. Since I plan to use the AFR's I haven't decided whether to rely on the head or cam mfg to supply. Either use the upgraded springs with the heads or just swap the regular ones for the Comp springs. I still like the hydra-rev idea with a spec spring rather than over spec the springs.

 

To be honest alot of comps spring recommendations are crap. I dont know how they figure their data out but alot of them are off including their rpm ranges for cams. I'd just use AFR 8019 springs. That will work with just about any hyd roller.

Not familiar with their lifter packages but i think their base lifters are no better than stock and certainly not as popular as ls7's which have a proven track record

 

My sentiments EXACTLY.
You'll get better advice on this board for component choice and matching the components, provided you can separate the experience-based advice from that of the internet-posting ****** , than you'll get from a Comp flunky on the phone.
Comp sells some good stuff; just don't rely on their phone "techs" to ....ahem.. "help" you. If you just need them to look up a number in a catalog for you, that's about the extent they're good for. To actually get technical help from them, you almost need an inside track to someone there who graduated from the phone lines decades ago.
And, I'll continue to trust GM's quality control over their suppliers more than I will Comp's.

 

I have never used oem roller lifters but from personal experience with the aftermarket:

COMP hyd. on my 383 ran for 12 years with plenty of dragstrip time I sold that engine and it's still running strong in a '57 chevy show car..

Crower solid on my 421 revving to 6800 going to try 7200-7400 next season, but so far so good.
We shall see how long these parts last in a 6800-7400 RPM application.
It should be fine with the parts I have but a 4-5 year tear down/inspection will probably be part of normal maintenance. Depends how often I run it.
Time for a new Log Book. so far 4 passes on the new engine.. & 7 on the trans.
since I am N/A the only "abuse" on the motor is the high revs.. but this motor was built to rev. If I was shocking the bearings with a lot of N20
or running a procharger.. more like every other season you go thru the motor to check it.

I never touched the 383... but it also made peak HP at 5800 rpm it was a street / strip car. OEM lifter could have been OK to use.
LOL keep it under 6400 and your motor should last forever ! I filled 2 log books. rebuilt the trans and converter once in 12 years

IMHO OEM parts don't belong in a "race" ( > 6500 rpm ) engine . but that is just my .02.

 

There are oil priority solid roller lifters in use for long term street driven cars that work when a high volume oil pump is used.Idle and all.

 

How so?

 

If you're still thinking Comp, when I was sorting out my lifter problem, the rep suggested that applications beyond 6500 rpm where better suited to their short travel lifter. Available link bar or retro, also tall body.
Similar to Morels I believe in that they have a very limited plunger travel and take only a small amount of preload. The angle here is to reduce the amount the lifter will "pump up" should there be any componet separation at high rpm. Of course with a well designed valve train, the likelyhood of that (separation) happening is reduced.

 

Well this thread did sort of morf into a build discussion, and that's ok by me. It basically comes down to head port size and cam & valvetrain selection. Here's the basic plan and variables.

Known details;

420 dart shp block- Callies RA with Wiesco 10.7 CR
Heads AFR
Hydraulic roller cam/valve train
Holley Stealth Ram intake OEM control
1 5/8 shorty headers/Single exhaust
TKO 600 5 speed/std weight 153t flywheel/3.27 rear gear
Power brakes compatable
"Daily driver" friendly Decent idle/great mid torque
5800-6000 peak
Goal: 480Hp net at the crank

Some of the variables;

AFR Head port sizes 195 vs 210
Cam- 230 to 240 @ 050- max lift that will still give decent service life. I like the Comp XE/XFI & Magnum lines. Don't believe I need the 112+LSA with big motor but still must retain computer compatability (I can tune the program) Not sure if a single or dual pattern cam would be best. Want to keep big midrange power.
Was planning to get full kit from Comp with OEM style-(probably short travel) lifters but now may use LS7 lifters. Will still need cam plate/guides/spider if use OEM style lifters.
Comp steel roller rockers. 1.6- (if split duration cam may use 1.6I/1.5E ratio rockers)
Have 7\16 studs, may use girdle.
Interested in AFR's hydra-rev kit.
Injector size
TB size. Will be using stock 48mm with air foil for now. Sort of a poor mans power limiter during break in lol.
Clutch. Thinking Centerforce here- need good holding but it's gotta be traffic friendly. Would consider going to 168t flywheel if it would give me a better holding clutch by diameter increase.

Some have mentioned custom cam grinders. I would really appreciate being able to give all this detail to someone who is proficient at spec'ing street, EFI cams. Would this be considerably more $$ than the major cam companies?

Any input regarding the whole combination will be great.

 

It seems the only time Comp's spring recommendation works out ok for a particular cam is when it's paired with a poorly flowing or low-rpm oriented heads/intake system. For instance, in all LT1/LT4 applications, a particular cam's power curve will be at least 500 rpm higher than their assumption, and consequently their recommended springs will inhibit you from getting maximum performance out of the build.

 

Exactly! That's why I preload my stock LT1 lifters to only 1/8 turn past zero lash. Even though I think I have everything covered with my valvetrain setup, why risk it. I may be leaving a little power on the table with the "hydraulic cushion" of the lifter giving up some valve motion as compared to a solid or short travel lifter, but until I see somebody with those high dollar parts performing better than my thrifty motor does, I'm happy with it as is.

 

Sometimes abit more money sometimes not. Depends. I have used bret bauer with good success but my cams and alot of his customers are more racey. Also used mike jones from jones cams. He does anything just about and can give you a mild lobe. Also heard chris straub is good. Does alot of hyd roller big blocks on chevelles.com. Also does sbc tho.

I agree if you can tune, a tighter lsa would help. 108-109 lsa with a 236/236 or close to that would be great imo.


Regarding comp cams spring recommendations and rpm ranges, you just need to look at real life examples using those components and even some of comps dyno tests. I am only familiar with their hydraulic stuff. Flats they seem to recommend the 981 springs for all their grinds but a stiffer spring is needed for the higher duration grinds. They had a test of all their xe grinds where bigger cams do not pull more rpm and show early drop off in power at higher rpms than some of the smaller cams on same setup. Motor had large enough heads that gains would have been seen

The xfi series need more spring than most realize depending on valve weights. But the 280xfi in the right intake/head combo is more than 6200 rpm. That cam turns 6500 all day long on 355's with short runner intakes. I am not sure what they base their data on. Stock heads? What intakes? They recommend 918 beehives but those float at higher rpms on the bigger xfi lobes. One member here floated the valves on 268xfi but the springs were suspect, could have been a weak batch as they tested weaker than advertised.
Other comp springs like the 986-987's for other mild rollers are ok but seat pressure isnt high enough for aggressive lobes. My friend ran similar spring spec with the 280 xfi and it was a mess above 5700. So i'd talk to a more knowledgable valvetrain person like a custom grinder, other experienced engine builders, or even a spring company like pac springs or psi springs.

 

First, the easiest one: the HydraRev kit ........that setup is of questionable value compared to a simple properly set up valvetrain even for more extreme builds. With your targeted rpm range, it would be a complete waste of money and just another possible failure mode in your engine.

480 crank hp: that's going to be easy for 420 cubes with any reasonable head and cam options you're considering.

1-5/8" headers: you'll make your power goal, but 1-3/4" would be better suited and wouldn't give up any noticeable low and midrange torque with your cubes. I swapped from 1-5/8 Tri-Y's to 1-3/4 conventional 4 into 1's on my 350 motor, picked up 15-20 hp at peak, lost nothing anywhere that I can sense, and improved my 60' times.

Single exhaust: I hope that's at least a 3-1/2" with no compression bends. If not, it could be the deal breaker to your making your power goal.

Head port size: for your cubes, I'd go 210cc. Just make sure your exhaust system lets you use it I was apprehensive running 200cc heads on my 350 motor (was considering 190cc), but was really surprised at the low/mid responsiveness. With the relatively tight street converter I originally ran in it, street tires didn't stand a chance from any speed.

Cam: I know AFR's exhaust ports are generally strong, but still would look for something with a 4 to 6 degree duration split favoring exhaust. At the risk of generalizing, I think you should be looking for something in the mid-to-high 23X intake duration. That should make .600'ish lift possible with 1.6 rockers without resorting to valvetrain-abusive ramps. IMO, given your moderate rpm target, there's no sense pushing duration higher than that. Wild guess says you'll end up somewhere around 110 LSA for ease of tuning and a reasonable idle. I think something like Comp Magnum high lift lobes.. 236/242/110 ..would do what you're asking. If it were mine, I'd get help on a custom grind from Lloyd Elliott or Advanced Induction. They're both well tuned in to what works well with intakes like the HSR on various cid. They're also your best resource for what springs to run with their particular cams.

7/16" studs with guideplates and NSA rockers will be good for your rev range and resulting springs you'll need.
Edit: NO girdle required with the springs for your rev range.

Injectors: I know I'll get an argument or two here, but 30 lb SVO's or equivalent will be plenty. Those are good for 600 crank hp in NA applications.
Unless you're roadracing it on long tracks or doing top end speed record runs, running a high duty cycle is of no concern, and you'll gain a slight edge in low rpm performance running a smaller injector.

48mm TB: this will be a restriction but will certainly not keep you from your 480 crank hp goal. Down the road, I'd plan on a 58mm.

 

I've used a Centerforce DF clutch for quite a few years....nothing else exotic and it's held up well. And that's holding 495 ft lbs of torque at the wheels.

 

Yeah the exhaust is my problem short term. I do have a custom cut out at the "Y" so I can see how bad it is on the dyno. I may redo the entire exhaust or at least the "Y" back as one of the first "mods". I know the TB may be the next.

But into the build/combo itself, I think we are all pretty close in regard to cam selection. I will check into some of the custom grinders mentioned.

I also agree on the injector sizes and duty cycle. I have not ever experienced any fuel starvation issues with the 22's at the previous build level.

Now just got to get this thing built. Block/RA should be on the way.

BTW what do you mean by NSA rockers?

 

Without rereading the whole thread,are you going for some sort of data recorder for aleast being able to monitor A/F/R's??.

 

Fact is, unless you run a set of duals that dump out before the axle, getting a decent exhaust on one of these cars isn't easy, There are however some very nice examples of twin exhaust pipes going over the axle to either a muffler in the stock location or some adaptation of two mufflers installed after the axle.
Keep in mind, it's not only the size of the exhaust pipe that determines the flow potential but the CFM capability of the muffler(s). A general rule of thumb is that 2.2 CFM of muffler flow per HP before the restriction starts to limit output. Again, many have had success with less however that leaves the question, what are they leaving on the table? For your power goals, 480 CHP(?), that's about 1000 CFM of exhaust system flow. Having the correct size of pipe is obviously important but finding a 1000 CFM muffler isn't easy. At least not one that you could live with day in and day out on a daily driver. A pair of mufflers at 500 CFM each is a little easier but finding a spot for them isn't.
Your exhaust cut-out is an interesting touch. Testing with my last track-worthy car netted 2 mph in the 1/8 mile in back to back to back runs with my crappy Flowmaster muffler vs having the cut-out open just before the muffler. That Flowmaster MIGHT have a potential flow of 300-400 CFM. You can see how it's a major restriction in the system.

I believe NSA rockers stands for Non Self Aligning.

 

Good mention about the muffler, skinnny. I tend to forget about that since I'm not making those power levels in an F-body.
Just to back that point up:
1. Even with a good dual 2-1/4" exhaust with H-pipe behind the stock LT1 in my Impala, uncapping the exhaust increased rwhp from 299 to 309 on the dyno.
2. With the current motor in the car (~540 crank hp), and a much better 2-1/2" dual X-pipe exhaust, there's a 2 to 3 mph difference in corked vs uncorked. At 120+ mph and my weight, that's at least 30 hp at the flywheel.

 

Good luck with it!