smithtc

iTrader: (5)

Dropped them off this morning at shop for crack testing and cleaning. Man tells me that they have bronze guide inserts...and that they look like they are 70+ cc heads. He compares an angle milled set of 624 heads that are 64cc to mine for me to see the difference. He also says the bronze guides were not factory installed, and that they appeared worn. I had a couple of valves in them at the time. He also told me that I wouldn't be able to port these heads enough to flow better than out of the box World Products, Dart, etc.

I am planning on a valve job, porting, and stock size Manley valves if seats are good. I've read some posts where good flows are achieved on these heads. But is this guy BSing me on the combustions chamber size Also, did any factory heads come with bronze guides, or, are they easy to distinguish by just looking at them? He said he was going to check the valve guides for clearance, but can you just move the valve around by hand and be able to tell just from experience if they are worn? They seemed pretty tight to me. My dial caliper checking skills may be poor, but I detected very little wear...actually none.

It's one of the few shops in my area with a flow bench...but maybe I need to take my heads somewhere else. Especially if he tries to tell me mine are crap and I should buy those 624 smog heads that are angle milled.

Any advice???

RB83L69

Do not buy any 624 heads. At one time I paid people to take that garbage off my property; but I've grown up some since then. Now, I might merely shoot people I caught leaving trash like that on it.

He is correct, the factory never installs bronze guide inserts.

What is the casting number of the heads you think are L98 heads?

It goes without saying that you're not going to be able to outflow racing heads by porting a bunch of stock ones.... if you could, we wouldn't need companies like AFR, Dart, Brodix, etc.

Pics would really help too, but the casting number tells all.

smithtc

iTrader: (5)

they are the
14101083...87-up...350..........Gen.I, also used on crate motors, 285 or 300 hp, 64cc
chambers, 72' center manifold bolt
angles

from an 89 GTA w/ a spun rod bearing w/ about 100K miles.

He's charging me 50-60 bucks for crack testing and cleaning BTW.

I also now recall all of the valvesprings having shims underneath...that I threw away. Maybe some work was done on them.

Aron213

this guy must have the best eyes ever if he can see CC's...083's have 64+/- chambers. You can tell if guides are worn by feel, but I have seen that the newer GM heads come looser than that of the older generations.

If these heads have bronze liners and had Valve Spring Inserts then these heads have been off before and had a valve job at least.

RB83L69

The 083s are the L98 heads. So they're 64cc more or less, as they came. Like Aron said, they've obviously had some work done before.

Get them freshened up, and run them. They're a whole lot better than any 70s smogger sedan crap like 624s.

As far as guide clearance, as long as it's not more than .003" or so, they're fine. They usually are fit to about .0015" when installed, and of course they wear some as time goes on, it's not like if they're .002", they're used up. But of course, they're extremely easy and cheap to replace even if they are worn out.

Don't worry about the shims, they're real cheap.

Just have him work your heads, tell him you're not interested in his 400 heads.

Vader

And don't worry about the shims at all if yo're installing new valves. Any shim under 0.050" isn't even really worth the trouble on a relatively stock setup. The springs aren't that critical (or that closely matched) anyway. It's amazing how much people fret over the things that really don't matter much and overlook the important items.

$60 for hot-tanking and crack checking? Are you buying his supply of crack? Seems just a little steep to me. Maybe prices there are a bit higher.

F-BIRD'88

These 083 heads can be ported to meet or exceed the flow of
"Out of the Box" world Sportsmans (225-240cfm) the dart iron eagles are a little more.
He's obviously never ported a set of these heads.
If 240 in and about 180+/- ex cfm@28 is good enough for ya just port these heads yourself. You'll probabily do a better job than the shop can. Consider going to a 1.6" exhaust valve.
Rock the valve in the guide. If it does not appear to have excessive guide clearance then it's probabily ok.
But to "re-line the guides" is not expensive.
As said above: don't let this shop steer ya inot their junk 624 heads. Yours have lots of potential.
Get a full estimate before commiting to this shop.
Shop around.

smithtc

iTrader: (5)

He is shot-peening them also, if that makes a difference in the price. I was told he was high, but that he worked on race engines and that he was one of the better shops...This guy was one of three shops recommended to me. He is the only one of the three with a flow bench, which I was planning a before and after on my 1st port job.

I was planning to get new springs that would match my stock cam with 1.6 rockers.

Since these must have had some work on them, there should be seat recession, right? IIRC a good way to correct that is increasing the valve size.

Appreciate the sound advice. This guy was one of three shops recommended to me. He is the only one of the three with a flow bench, which I was planning a before and after on my 1st port job.

smithtc

iTrader: (5)

No cracks.
Guy succumbed to them being 64cc after looking them up, and then making a comment about the plug boss(?) extending into the combustion chamber.

Getting a base line flow on 1 intake and 1 exhaust port.
Flowbench costs $50 bucks an hour. Said it would be about a $100. Other flowbench in the area wanted $150.


Looks like I will need to upgrade the valve size from the stock 1.94/1.5. Think I'll try the 2.00/1.6 sizes and see what this beginning Master porter can do.

AJ_92RS

Looking them up? He should also measure them. It's not very difficult to do.

By saying "see what this beginning Master porter can do.", I hope you mean yourself and not him.

One more thing, and this is strictly my opinion... Don't bother getting them flow tested, unless you're using them for strictly racing. According to www.Mortec.com, they're these heads...

They've been proven to flow pretty well (as F-BIRD'88 pointed out) once they're modified. So why pay someone to tell you what you already know?

Riley's35089rs+

and the port work is expensive ....do it yourself!

smithtc

iTrader: (5)

I'm the beginning porter hopefully I'll be a Master Beginner
I'm flow testing them to get a before and after...to see how well I do...or how well I screw up
Then with the flow numbers, I will try and better match up a new cam. That's the plan.
Right now I'm hoping for some feedback on valve size.
Still going to port match, pocket port and bowl blend cautiously.
WIll also use roller rockers, screw in studs.
Do I need guide plates? Shop recommended them, and 3/8" screw in studs.
Induction will be StreetRam Intake/Runners/Plenum which I am currently running.

I tell you what. These heads look perty after the peening.
Edit: Actually it was glass bead cleaning according to my receipt. Total cost for the glass bead cleaning, magnaflux, checking for cracks and leaks was $53

Riley's35089rs+

oh yes they do shin up..check I these 416's I just sold on ebay for 500.00
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2413775958

F-BIRD'88

Don't bother flowing the 083 heads before porting
here's the numbers

-------083 heads-------113 heads-----

Intake
0.100.......44..........62....
0.200......101.........115....
0.300......155.........161....
0.400......182.........185....
0.500......196.........195....
0.600......202.........198....

Exhaust
0.100.......41..........49....
0.200.......82..........98....
0.300......125.........130....
0.400......137.........152....
0.500......140.........159....
0.600......141.........156....

You can save a lot of money by just getting a peak flow test at high lift. Should only take up about 10-15 minutes of that shops precious time. No need to setup and adjust the valve opening fixtures and test at each lift point. Just test at a high lift while holding the valve open by hand. Porting will have the most effect at high lift anyways. Be sure they use a radius inlet (putty)
on the intake port thou.
If I had to spend an additional $300 for before and after flow testing, I'd just go and buy a set of aftermarket heads.
Unless you're building a National Record Holding Superstock Motor
using a stock casting, putting this much detail into it just takes the fun out of it. You'll know soon enough wether your efforts were worth it the first time you step on the gas.
Using David Vizards direction on home porting chevy heads will get most people in the 230/240 cfm intake flow range.
You can get more but not with one head or one flow test.
This will make you a responsive powerfull street/strip performance head. Especialy if you put more sweat into the porting work detail and don't sweat the numbers.
Good Luck

AJ_92RS

F-BIRD, I'm ashamed of you.

You failed to mention that high flow numbers DON'T mean more HP/torque. I can hog the crap out of smog heads like the 624's to make them flow ~220 cfm @.050" of lift, but that doesn't mean I won't disrupt the flow enough to totally destroy any chance of making good power.

It's all in the hips. It's all in the hips... OOPS Wrong line

Just messing with ya.

smithtc,

Go to Barnes & Noble and buy this book, or buy it online.
(Click on it)

F-BIRD'88

I agree: a high flow number at high lift isn't the last word on port flow but will be a good indicator of how much improvement
he's made at a modest price.
Low and mid lift numbers are very relevent to makeing good horsepower and torque. But using these techniques and a larger valve his low and mid lift numbers will be good, Much better than stock.
But for for bragging rights the high lift numbers are where it's at.
They also are a good power *indicator* of the the horsepwer potential of a motor with these heads on it. Especially with other improvements like a high lift cam and intake and exhaust tuning.

smithtc

iTrader: (5)

Here are some of the flow test results off of a Superflow (I'll try to get a scan of the sheet on here later if anyone is interested)...
14101083 heads 1.94 intake / 1.50 exhaust
numbers @ 28" of mercury for comparison

Intake
Lift_______CFM__Potential (based on 1.94 valve area)
0.097..........52.................66
0.194..........101...............131
0.291..........145...............196
0.388..........167...............226
0.485..........179...............242
0.582..........185...............253

Exhaust
Lift_______CFM___Potential (based on 1.50 valve area)
0.075..........35.................38
0.150..........62.................78
0.225..........87.................114
0.300..........105...............152
0.375..........106...............165
0.450..........106...............171

The fella basically said the lift numbers are what the flowbench specs called for. Not quite sure how else to say it.
Flow numbers not ideal, actually lower than what others have posted, but potential is there. The exhaust is much poorer than what F-Bird shows above.
I have decided on 2.02/1.60 Race Flo Manley Valves. Looks like I've got my work cut out for me. I'll see how artistic I am with a grinder...

F-BIRD'88

the funky lift figures are based on a ratio of the valve diameter.
trouble is the lift points are going to change on the bigger valve.
(Using the same ratios)
A good way to qualify a port's flow with a certain size valve, as compared to a bigger valve etc but can confuse you when you're just going to start with a bigger valve reguardless and make the best of it. The rest is academic.

The test method used and setup on the bench has a lot to do with the actual numbers you get. looks like a test without a radius inlet on the inlet side and no pipe on the ex side.
Which is quicker but gives lower numbers. I hope this didn;t cost you a lot.
If these are the actual results of your heads on a bench then the only way to compare your gains is on that same bench using exactly the same setup and methods. And at the same lift points.

I'll go along with the "potential numbers" in the chart.
These agree with what I've gotten on my simular heads after porting. Good Luck

iceman02

iTrader: (1)

Here's a set of L98 heads I ported... I really had to expand the intake runner entries to match them up to my intake manifold which is port matched to a Felpro 1206.

iceman02

iTrader: (1)

but in the end I finally got them to match up pretty well.