brodysZ28

I had my car dyno'd last week with these results.

Engine:
383 SBC, maybe 20,000 miles or so
Pro Comp 210cc heads
11:1
XR288HR Cam
Full roller 1.5:1 Comp Cams Pro Magnum rocker arms
Performer RPM intake (non air gap)
Barry Grant 750cfm mechanical secondary, no choke
72p,96s jets
HOOKER 2055 HEADERS (1 and 5/8)
2.5" Y-pipe, slightly dented passenger side bend
3.5" back through dynomax race bullet
Timing set at 36 degrees, we played around a couple degrees here and there with no major changes

Tremec TKO 600 transmission

Strange S60, 3.73 gears

The only thing I am seeing here is possibly the headers limiting rpm and power. But really? I know it is possible to make a lot more horsepower on that size tubing headers... is it the design or welding at the collector on the inside of these? Or am I missing something here? I was expecting around 375rwhp. Is that unrealistic to expect?

Also, what do you think about that air-fuel curve?

What does everyone think?

Orr89RocZ

iTrader: (20)

Longtubes def will help some but i dont see 50whp there. Hard to say. Have some loss in the strange s60 rear, more so than stock rears.
Air fuel looks ok did you try richer and leaner than 12.8? Its fat below 3500 ish rpm but not sure where pull really started, is it 2500-3000?

Curve is really wavy tho? What smoothing factor used?

1.6 rocker on intake should help some but intake should be opened up some, ported plenum and such. Should get a few ponies.

All added up there are gains to be made

sofakingdom

iTrader: (1)

A/F ratio looks in the ballpark; maybe some room for optimization, but, nothing just massively defective or anything like that.

The headers are a limit, for sure; but it doesn't look like you're even close to that. You're several 100 rpm shy of hitting those. Prolly 500 or so.

Looks to me mostly like a valve spring problem. "Pro Comp" pretty much says it all. What springs are ACTUALLY on there? (not, "whatever they supplied"; not, "Iunno", not, "what [fill in the blank] said was enough"; PART # ONLY please)

Your rear is a MAJOR RWHP sucker. Prolly 30 - 40 or so less than say a 7½". Yours might last AHELUVALOT longer, but will slow the car down in the meantime. Make the appropriate mental allowance to the "peak" numbers for that.

Also, might want to calibrate the dyno against track times. The absolute raw #s from the dyno may or may not be what you "expect", and so should be verified against the car's ACTUAL MEASURED behavior. However, all you curves look like the motor is all done at WAY LOWER rpm than it should be. I don't see a "power" or "torque" problem, as such; I see a RPM problem. It just doesn't have the nads as it winds up.

I'd mostly be looking for something not directly flow-related, but RPM-related all the same. Valve springs.

cardo0

Well u did have 380ft-lbs. Yea the power curve dosent really peak more like flattens out and gets jerky up top and quits before 6,000rpm. I would say both small tubes and vlv springs. Im saying small dia tubes not length. I think u need larger dia pipes regardless of length. And i dont know how much vlv float can be transmitted through the clutch/trans and rear tires but i think i see some vlv float there. I think that cam should pull well above 6,000rpm.

Maybe air cleaner is choking it too. Did u run with the hood open?

Anyways Comp has dyno graph of a 356" motor using your cam but with lessor heads and less compression than yours. Granted the Comp graph is an engine dyno. The torque curve matches yours well enough but the power curve is over 400hp at 6000 and still climbing - nothing flat with that curve. Your cam has some good lift even w/o 1.6 rockers. Ya know the vlv springs need enough clearance between retainer and vlv guide boss/vlv seal. Most say 0.060" safety margin. A smaller clearance may function at lower rpm but start to collide as rpm and rocker/vlv assembly velocity increases. BTW comp used 1.75" header tubes on that 356" motor.
I would try the next step up in vlv springs or at least measure the retainer to seal/guide boss clearance. Also larger tube headers.

Night rider327

iTrader: (13)

Another vote for valve springs.. Looks like they are limiting your upper RPM.. That cam, intake and head port size should pull to 6K, if not 6500 rpm with out any trouble.

You pretty much top out at 5300 rpm

brodysZ28

Good responses. I have had the car at the track and ran 13.0 @ 108 multiple times and a couple of passes on track for high 12's at 110 or so before I ran out of fuel (separate issue).

I did run it on the dyno with the aircleaner off. I am not totally sure what smoothing factor was used... the sheet says smoothing:0. Is that it? I will try to track down the spring p/n today.

I did notice too that there was a little play in the distributor shaft which didn't feel too out of norm to me, but could excess play/spark scatter at high rpm be doing something as well?

Orr89RocZ

iTrader: (20)

Smoothing of 3-5 will clean the graph up but yes it isnt pulling the rpm that cam should. I guess the performer rpm dual planes will go to 6k rpm so your power should continue to rise til then. Not to familiar with pro comp heads tho, they definately arent the best available and ports could use some clean up work but still should support some more power given the flow numbers and port size

86LG4Bird

iTrader: (1)

My money says valvesprings. REALLY poor valvesprings! It looks like they lose control starting already in the 4000-4500 rpm area.
While not spectacular, those heads should support a power curve that continues to climb to at least 6000 rpm.
The headers are not your issue. I've made 425 SAE to the wheels in a 350 with better heads, smaller duration cam, through an auto trans with 1-5/8" Tri-Y headers. Changing to 1-3/4" conventional 4-into-1 longtubes gained 15 hp on THAT motor. With yours in its present condition I'd expect about zero gain. Even after you solve the rpm issue, changing headers would probably gain you less than 10 hp.
I don't see that dyno being pessimistic at all. 110 trap with an assumed race weight of 3600 lbs shows about 320 rwhp.
I agree you should be seeing closer to the 375 rwhp number.

brodysZ28

These heads are not comparable to a set of quality AFR, Trick Flow, Brodix, Profiler, etc... but they should make decent horsepower and flow well north of 6,000 as it seems like you guys agree with.


So, the valve springs are melling 274. They came assembled on the heads.


Seat pressure 125lbs @ 1.950" Open pressure 385lbs @ 1.250" Max RPM 7,500.


http://m.ebay.com/itm/350241405821?ul_ref=http%3A%2F%2Fr.ebay.com%2F9QiMCo%3Fsrcrot%3D711-127632-2357-0%26rvr_id%3D871265044792&_mwBanner=1


I'd have to buy a spring compressor and airline fitting, but I could pull one off and test its open pressure. Melling isn't known for being low quality though are they? I mean I do wind the car up fairly often and it has been together for almost 4 years now.

Orr89RocZ

iTrader: (20)

They can lose pressure over time. Those specs arent bad but i rather see closer to 140 seat pressure and 400 open on bigger hyd rollers like that.

Make sure pushrod length is correct and you have good rocker geometry. Check for valveguide wear. Right spring but bad geometry can lead to guide wear which will then give you float

Those are tall springs. 1.95" install height where most others are around 1.800". Tougher to find a spring for 1.95" but there are some out there.

brodysZ28

When I built the motor I measured for pushrod length and checked to see it was right on the center of the valve, so that should be good... I never noticed anything weird happening with the geometry... that is after I replaced one of the heads due to bad rocker geometry. I had Skip White warranty it.

brodysZ28

I found a guy here it CT that has the on-engine valve spring tester. I am hoping early next week we can do a quick test on a few and make a conclusion. I got the carb. all back on and running yesterday and noticed there was some valvetrain noise going on on the passenger side. Now I just re-lashed those valves 3 months or so ago because I was hearing the same noise. It isn't too bad but I wasn't happy with it. Will weak springs lead to some ticking? It isn't a clatter yet, just a tick. It isn't exhaust either.

TTOP350

iTrader: (8)

Full roller rockers make a tickiking/clattering type of noise,

Dominic Sorresso

Has it been suggested to try go to 1.6 ratio rockers? Might be faster/cheaper than swapping cams. See if the added lift helps. Also, assuming you degreed the cam.

brodysZ28

It's much worse on the passenger side and usually is not this noisy.

brodysZ28

I've seen dyno graphs close to 500hp with this cam, so lift and duration is there.

Orr89RocZ

iTrader: (20)

Lifter collapsing?

Cam will make power just need to control it and have induction package do its job

TTOP350

iTrader: (8)

Losing a rocker or lifter? maybe even losing a cam lobe? (wouldn't surprise me if its a comp cam)

brodysZ28

If I have time tonight I am going to pull the valve cover off and see if I can feel a bad lifter, take a look at the springs, rockers, etc.

-=Z28=-

iTrader: (3)

Is this a Skip White engine?

brodysZ28

Nope, I built the engine. First build. I just used those heads from him.

brodysZ28

Looks like definite valve float.

brodysZ28

More

brodysZ28

-=Z28=-

iTrader: (3)

That sucks, How many valves got buggered up? A shop can re-face those and check to make sure they are true. So now what, New springs, fix these?

-Dan

Steve Mack

iTrader: (5)

Looks like very cheep Chinese valves.Those valve tips don't even look like they are hardened like good valves should be.I'd say more Skip White junk.Scrap the heads and get an American made brand.And don't buy Skip White junk.Penny wise pound foolish.

Orr89RocZ

iTrader: (20)

Could reuse castings and get new good valves put in. Or run lash cap but those tips do seem very soft for a valve stem. Lash cap may not help there, but def needs new springs

brodysZ28

I didn't dig too deep but looked to be about half were that bad. Bare minimum the heads are coming off and new valves and springs are going in. I'll have to evaluate them better when they are off. It's just the time though... Home owner, work full time, starting my masters degree in a month... Idk how guys do it with a family lol. I doubt I will have it back together before winter. Depends how motivated I am I guess. But knowing this, I'm actually kind of surprised it made the power it did. It should have a good amount more in it once it can hit the rpm. That's a good thing at least.

Night rider327

iTrader: (13)

Check out competition products for good prices on valvetrain parts.

I have been using these valves for 5 years now. http://www.competitionproducts.com/S.../#.VbG2PqRViko

Or being you need springs and valves look at their "head improvment" kits
Like one of these 2
http://www.competitionproducts.com/H.../#.VbG3wqRViko

http://www.competitionproducts.com/H.../#.VbG30aRViko

Damon

Replace (don't reuse) those valves. Get some good quality brand name valves, stainless steel if you can afford them. While you have the head apart, might as well have the shop check out your valve seats- they're probably crap, too.

As for springs... you should always use the ones recommended by the CAM MANUFACTURER.

The springs that are in there now (if the specs are accurate) are DEFINITELY for flat-tappet style cams. Notice how the open pressure is only 385 lbs.? And it doesn't even hit that number until .700" lift!!

sofakingdom

iTrader: (1)

Looks pretty grim.


Looks like the result of coil bind and/or valve float, with the valve tips hammering on the rockers.


Wouldn't be surprised to see seat damage as well from the valves beating on them at closing time as well.


Definitely a valve spring problem from the start.


Consider spring specs: if they spec a 1.95" installed height but you put em in at 1.75", then ALL of the other "specs" get moved down .200" as well. So if they're "rated" for .700" of lift at 1.95" installed, but are installed at typical SBC height of 1.75", now they're .500" MAX.


In the pics the coils SURE DO look close together.

brodysZ28

I don't know what the actual installed height of these springs are on this head with these valves. That has to be just as much of a factor as the spring itself. I did talk to comp though and they said the specs are more than enough for their cam. The springs comp recommends are 120 on the seat and 343 open.... but I have no idea what heights those numbers were at.


I can get Manley budget series performance valves for around $250 all together... springs another 90 then what 60 for retainers and keepers. Valve job? idk what those go for... $200? Then my time to do it all with the help of a buddy who has the tools. $600 plus time.


Or... Profiler 210 for $1,140 assembled? 2-bolt block though and eagle rotating assembly... idk how much power I should really try to push.

-=Z28=-

iTrader: (3)

Careful when pulling those valves through the guides. Make sure they are burr free..

Orr89RocZ

iTrader: (20)

Lol avoid comps recommendations. They make ok cams but generally are off on their spring specs. But 385 open pressure if at or near your cams lift is enough for that cam. Seat wise however i feel it should be higher than 120's.

Measure the install height when you get a chance and from there you will know what you need. If it is closer to 1.75-1.8, then good chance that spring coil binded and amazing it didnt break.

brodysZ28

I can't see how they wouldn't have broken if they were binding this whole time. I will have to take a measurement Sunday when I get back.


So I was looking at some dyno charts for the xr288hr and kind of comparing it to my curve. It looks like the valves began to float right around 4,000. If the curve followed the path of other graphs I would definitely have been in the 360 - 380 range. Knowing that, would you guys think these heads do okay power wise or would it be worth spending another 500 or so to go with a set of pro-filers (or is there another 1100 dollar head that could touch those)? Maybe make 400 to the wheels?


Chad Speier looks like he sells a quality set with nice parts. I don't think I am ready to drop 1500 on AFR Eliminators or the Econo port job from Speier.

86LG4Bird

iTrader: (1)

If no issues than valvetrain and you're satisfied with 360-380 hp (yes, I think you'll be there when you fix this issue), then I don't see the logic in changing heads now.

Orr89RocZ

iTrader: (20)

More power you want to make the more that exhaust becomes a restriction.

I would fix valvetrain issue and see what it gets you. If you want more power now, profiler/jegs 195-210's would do well for the money. Even dart shp 180-200's. Some say the 180's are actually measuring 195-196 ish and flow better than the 200's.

You can get a shp 180 head and send to eric weingartner for a $350 basic port clean up and they will support over 475 hp.
Speiers econo stuff is also a good idea. Think he still may offer the import head casting as well for abit less.

Or have someone clean up your procomps for abit more flow and put good components in it

TTOP350

iTrader: (8)

Looks like valves didn't get hardened at all. Lot of good suggestions so far, good luck.

cardo0

Its really your call buying new heads. But the internet postings i found for Pro Comp 210 heads all say the stock hardware is lousy. And u can read where the savings come from using these heads is reworking the heads then installing new hardware. Seems some owners buy the heads intending to rework them and upgrade the hardware where is works out cheaper than quality heads. But do your own search and research here.

Im reading more that Eric Weingartner does quality work and if your fixing the same heads i would see what he says and charges. I read he does a lot of work as requested not just a another copy of the same work done before for someone else. I cant say i have any heads worked by Eric W. but sure would like to read of someone else using his heads and has to say.

Night rider327

iTrader: (13)

Did you not look at the links I posted.. $180-230 for everything you need parts wise.
Valves.... Back cut, stainless, 1pc. swirl polished, hardened tips
Springs
Locks....Forged steel 10*
Retainers....4140 chrome moly 10*
valve seals

Pretty good stuff too.. I have ran those parts for 5+ years up to 7300 rpm

brodysZ28

Yea I think I will stick to cleaning up these heads. I'd like to gasket match them too.

Night rider327 I must have missed those links... those are good prices! I will have to look into those further.

How much difference would back cut valves make in a 450hp engine? 5-10hp? Or not even?

Orr89RocZ

iTrader: (20)

Hard to say on the valves but a good valve job for seal is important to have. Heads respond different to different angles. Would have to flow test the heads

brodysZ28

Hmm, decisions decisions... I'll update as soon as I have a plan together.

Damon

You should do yourself a favor and actually MEASURE the pressure of those springs at their spec heights. Wouldn't be the first time a set of heads came through with springs that weren't anywhere close to spec.

I know Comp Cams recommends their -986 springs for that cam (and have similar specs to the ones you allegedly have in there right now), but from personal experience I think they're too weak. A set of -987 springs generally work better with an aggressive hydro-roller cam like that.

But you MUST know your installed height first. If you think you're installing at 1.90" (a similar height to what most big block heads run) but you're actually at 1.75", which is what the -987 and -987 springs are designed for... bad things happen.

brodysZ28

I measured the installed height and got 1.94. Once I pull a spring off I will measure it just to see where it was at.

cuisinartvette

had something similar happen with rev good valves, springs etc
It was some imposter Manley knockoff pushrods.
hardening checked out but once put in a vise it only took the slightest pressure for them to bend then snap. Beat the heck out of the valve tip and ruined the valve job in 60 mi.

They were flexing all the time, might want to inpect those too also many put known cheap stuff in..can give a sound like valves out of adjustment too drove me nuts. Resurfaced the valve tips, new valve job real Manley pushrods and is just fine.

just something else to look at while its apart, in short. Id be inspecting the lobes and lifters also, not a fan of those cam cores

a 96 jet seems awfully big did BG put those in?

Add some spring pressure as Orr said 125 isnt nearly enough esp with these trendy faster ramp cams. Gotta "idiot proof" it as they say (not referring to anyone in the thread).

brodysZ28

I've never heard of the pushrod flexing theory before. I have Trick Flow .080 wall in mine. I will definitely be making sure they are still straight as well as really checking out the cam and lifters. I tuned the carb. I agree the 96 seems huge... but I can't argue with the a/f guage. High 12's like 12.8 is where it's at with 72 p 96s.

brodysZ28

Over the last week I have been getting info from here and there, all helping me to make my decision. I spoke to both Chad Speier, Eric Weingarter, and a local high performance, high tech shop Carlquist Competition Engines. I'm sure you recognize the names. Their advice... ditch the Pro Comps. They aren't worth putting the money into. After all I would have about 700 into them to make them work again. I was then 90% sure I was going to get a set of Pro-Filers directly from Pro-Filer for $1188 to my door. I was hesitant though because they use Mallory springs that sounded to have a real close spec to the ones that junked out. Still though Profilers make awesome hp for the dollar. Then I talked to Eric W. He said the quality he is getting from Profiler is on par with... Pro Comp. What!? The last 6 heads he got he had to disassemble and I think re-cut the seats. Right there I wrote those off. He said if I want a good, quality head for 100 cheaper get Brodix IK200's. They use good parts and have quality finish. I wouldn't notice the less than 10hp difference between the two heads he said.

So I placed the order today... but not for Brodix IK200, well kind of... Summit 200cc cylinder heads (same thing for less).

Heads
http://www.summitracing.com/parts/su...placementparts

Springs
http://www.summitracing.com/parts/cca-987-16

Valves
http://www.summitracing.com/parts/bro-br6169di
http://www.summitracing.com/parts/bro-br6170di

Might as well upgrade the intake while i'm at it... RPM Air Gap
http://www.summitracing.com/parts/edl-7501/overview/

I got a adjustable pushrod too incase I need a different length.

My compression will suffer .3 or .4 but oh well, I think it'll be worth it.

I think this combo will be good for over 400whp. What do you guys think?

Dyno Don

iTrader: (7)

They don't look like they are drilled and tapped for a temp sender.

brodysZ28

There are ports on the block right? I think mine is on the block now... i'd have to check.

Edit: Just checked and my sender is on the intake right before the thermostat. Looks like I can do the same thing with the rpm air gap.