olds 307 and 403

Those new castings have been out for awhile. I was hoping there was a more improved design coming out. You know a set that don't need pulled down and need machine work, other than milling. Maybe I might finish porting my #8 heads for the stroker. The big downer on using irons is lower compression is needed to not beat itself to death on pump gas. I won't consider anymore than 9.7 to 1.

slade69

New castings from who?

Right. Soon I have to make a decision between iron vs. aluminium. One downer with alu is the need of electric fuel pump. Not a big thing after all.


Need to decide the head volume to choose right parts for the bottom end.

Inline

I once calculated, that even having your "free" cores, which you lift from your engine, and not knowing any machinist who can do the work for you under the table, the cost of totally refreshing iron heads including new valves, valve stems, springs, new seatwork etc etc etc goes ridiculosly close to buying new set of e-brocks from the shelf without any discounts even, atleast here in Finland. No question which move will i do when i refresh my engine.

slade69

And my situation is even worse, because my "free" cores are cracked. Seems that if you can locate decent cores here, owners will ask paper money from them.
What you say about costs of machine shops, you are completely right. These things get me thinking e-brocks seriously.

slade69

Disassembled the short block last weekend. Typically, plastics from timing gear was on the oil pump pick up, and thus the chain a bit loose.


Also noticed that there are little differencies in two 395558 2 blocks. For example in lifter valley, there are kind of ribs in -69 block. They are missing in early seventies block. Few other small differencies also.


Something good, -69 engine seems really untouched, standard bore, std mains, std rod journals. -69 crank is "N"- crank, the other from early seventies is without "N".
Is there a big difference in Nodular vs. "Regular" cast?

cutlassefi

Or Procomps, which I think are better suited to a small block anyway because of the port entry size.

Jmo.

olds 307 and 403

The newer castings should be available from anywhere. Get the new castings already gone through by Bernard Mondello and milled to the 70 cc chamber size, especially being in Finland. I wonder it someone overheated or had too weak of antifreeze to cause cracks in your iron heads. Two good things about the mid 70's 350's are low wear, including the plastic timing gear. Any pre 76 block is plenty strong. The N crank is stronger but both are fine for most builds.

slade69

How about these, I think these are Procomps?
http://www.oldsrocketparts.com/produ...ylinder-heads/
There might not be other castings available today than e-brock or procomps.
I believed Procomps are Chinese copyed E-brocks. Are the ports different? What intakes will PC:s take?
I have mailed to OldsRocketParts, but they do not answer. Maybe they are not interested to make business overseas.
Another thing related being here near the north pole is, that Procomps with freight, taxes, toll fees, etc. are not so far from e-brocks from a local speed-shop.

Inline

Did quick counting.

Lets pick those 1089$ pair Pro-Comps for example. I used summit to generate shipping options to Finland, cheapest was DHL Express, 200,93$ for a pair of aluminium cyl.heads.
Now were on 1289$ total. Import tax for motor parts is 2.7%.
So, 1289$ x 1.027 = 1323,8$.
Now you add value-added tax in top of all that, 24%.
1323,8$ x 1.24 = 1641,7$

Converted to Euros, 1507€. And all that waiting and hassling with customs.

2286€ ( 2485$) for a set of new E-brocks and available from the shelf.

Long story short, in US you get a pair of Pro-Comps with a pair of single E-brock. But down there you "shave off" 350$ from price of E-brocks, already available when counting versus ordering Pro-Comps.
Makes E-brocks a bit more tempting looking from here. Since its already going to cost you shitload of money to build motor, atleast i rather pick the better part, especially if Pro-Comp is lesser copy from E-brocks?

1BOSS83

If 325 HP at the crank is the goal then aluminium heads and flirting with 10:1 compression is unnecessary IMO. Does this build have an estimated budget? I'm running 9.5 with 37* total and anything under 93 octane is unusable. The gas is only going to get worse over time and you don't want to have to put booster in a daily driver. I just finished a full 350 build carb to pan and I'll offer the same .02 I offer everyone with 350 build threads- decide your hp goal and what you're willing to spend to achieve it and the rest falls in place fairly easily.

slade69

That was the plan before I get to know my #5 heads are broken. With E-Bocks that would be stupid plan, I agree. Might be that E-brocks are overkill with 350 anyhow.
This "goal" thing you guys always talkabout. Kind of agree, but here in Finland you have to take in count what parts are available for you build. You can walk to speed shop and buy a set of E-brocks, but to find usable 5,6,or 7 heads is really difficult.

1BOSS83

If you can walk into a store a half a world away from where the motor was built almost half a century ago then I am of the opinion that the path of least resistance is e-brocks. You get the improved flow and if paired up with flat top pistons and a 0 deck you are 9.5 on the nose.

slade69

That's kind of odd when you think about it, but that's the way it really is.


http://www.uspartsperformance.fi/kan...bb-rpm-400-455

HWYSTR455

Couple things to point out here. First is that due to thermal loss on aluminum, you generally go 1 point higher on static CR over iron. So you technically wouldn't want to go below 10.25, 10.50-10.75 is optimal.

If you're having issues at 9.7 with iron, something is amiss with your combo. One thing that jumps out at me is the total timing at 37, think you should back that off to like 32-34 and see how that does. You could probably speed up the curve some too. Might want to review your whole curve, like initial, mechanical, and vacuum advance.

Another point is that your dynamic CR may be out of whack too, further complicating any detonation issues. If you run too small a cam with short intake closing events, you can ping with 9:1 static CR.

Too lean can also add to detonation problems.

There are plenty of folks running 10:1 with iron heads an not suffering from detonation using properly selected cams.

.

1BOSS83

That is very interesting, could you expand on this a little bit? Why does the type of metal used for the head effect a static concept like volume? Are you saying that because combustion occurs in an aluminum combustion chamber that the dynamic CR will be lower and thus you have to compensate with more static?

I'm not having detonation issues save for the one tank of 89 I ran. I am, admittedly, trying to guide the OP to keep an open mind about a lower static CR as gasoline will most certainly continue to deteriorate over time. I agree that my total seems very high but the performance of the motor has dictated that number. I've been through tests/tunes just on my preferred method of driving the car and 19 initial with a 18* curve is (VA hooked to timed port not FMV) has produced the best throttle response and overall seat of pants power. I'm running very cold plugs and a 160* thermostat, I should note that.

Point taken. However, I'd be curious to know how many 10:1 iron head 350's are sporting the designation of summer driver. I also wonder if the gearing needed to make that type of cam profile effective is too aggressive for the OPs goal. Certainly more than mine and my cam is most likely too large for my un-ported/stock valve sized #6 heads.

HWYSTR455

Steer WAY clear of oldsrocketparts in my opinion, he used to work at the 'new' Mondello, search here on experiences dealing with him.

.

HWYSTR455

Yes. Do your homework, you will see you generally want to go 1 point higher on STATIC CR with aluminum. Can ask a builder for confirmation. As for explaining why, it would take pages, so homework would save me typing.


Most destructive detonation is inaudible. You should read the plugs to be sure.


Mine's one of them. It's a daily driver at like 10.2 and some change, summer, AC on, in traffic, on 100+ degree days. Before I went EFI, on a questionable carb, on a 103 degree day, heat soaked, running AC in the staging lanes, I knocked off an uncorrected 13.66, drove 1.5 hours there and back. 3.42 gears and get about 18-20 mpg. It's my daughter's car, she drives it everywhere, so far from too aggressive. You can look at my build thread for specifics, and the EFI install thread I did. 180 t-stat, heat will cook your feet in the winter, and it has 22k miles on it since the build, so it gets driven.

I will be doing an overdrive for it though, 4L80E, and going to either 390s or 411 gears. That should get it in the mid-20s mpg. Not sure, may do 373s...

.

1BOSS83

Here is an interesting article on iron vs. aluminum heads:
http://www.hotrod.com/how-to/engine/...er-heads-test/

Judge for yourself but the numbers are fairly conclusive.

I e-mailed Bill Trovato about this thread and his response was

"Doesn't need to raise, but the heads would need to be milled to the desired CC.

Bill"


Just a heads up- I'm not posting all this in attempt to be combative but I want to give the OP a juxtaposed view as the head situation is a crucial junction in this build.

cutlassefi

You should've asked Bill about the difference in hp/tq vs coolant temps. He would've dodged that question like he was being shot at.

HWYSTR455

If you look closely at that article, the static CR of that engine is 10.88. They didn't get detonation with the iron heads, and I betcha they could have gone up a point on the aluminum ones and still not seen any det.

Further in that article it also states they didn't prove anything. And, if you look harder, they comment that the cam was pretty big.

Ever read suggested requirements for a particular cam? Like 'needs headers, aftermarket intake, and CR of 10.5 min? Why do you think that is? And some other, smaller cams say CR of 9.25 min?

I've talk to several builders who do performance engines, and have heard them say, regarding static CR, "build the engine right, and CR is what it is". You just have to cam it right, for one, and have the rest of the car setup for it.

I've seen a lot of people who for economy reasons drop to a more highway gear, from 373 to like 273 as an example, and then wonder why it pings.

Know why so many builders when they get asked the question of static CR on a 'street' engine they generically say "9.25 -9.5" ? To cover their' butts and get less call backs.

Look at new cars, and their' static CRs. The 'vette is at 11.5, and others are even more.

.

cutlassefi

But you can't do that on an Olds unless you had the same head etc., along with EFI that more accurately controls spark and fueling no matter what the conditions.
Go out and see how much timing your car will take when it's cold. Then compare it to when it's hot. It won't be nearly the same, EFI takes care of that.

80 Rocket

I don't follow your conclusion here. Is the cross sectional area of a Pro Comp smaller throughout compared to an Edelbrock? What is the runner volume of a stock Pro Comp?

HWYSTR455

True, it was an example, but you can get pretty close. I've seen 10.75 musclecars with aluminum heads do just fine, and Pontiacs over 11.25. Carb and conventional ignition. My driver was just that, about 10.68, 91 pump gas.

Point is, you get more leeway with aluminum heads.

.

1BOSS83

That's fine but the OP doesn't need anything near that level of CR for the HP goal listed. What I found interesting was that in a focused test where the only variable was the type of metal used for the head - The power number difference was a rounding error.

I'm trying to keep the big picture themes in the foreground here-
Gasoline is going to deteriorate over time so why spike the CR and run a big duration cam in a car with stock gearing and a 300hp flywheel bench mark?




Yes but there are some subtle differences between the LT1 and the OPs motor.

80 Rocket

What I have been learning as of late is that static compression ratio is just a number. That's it. It is usually something that someone along the way can hang their hat on for some sort of reason.

For instance, some guys can go 10.5:1 on iron heads and pump gas whereas others have problems at 9.5:1. Hell, I went 10.3:1 with no problems on a sbo. Anyways, here is a long post from my friend that insists on teaching me everything there is to know about airflow in a cylinder head.........and he keeps telling me about how he worked 10 years in North Carolina working for Nascar teams. Don't hate on him or think he is gay because his screen name is "fordboy628". I give him enough **** as it is.........anyways......

http://www.landracing.com/forum/inde...c,12353.0.html

Edit: To expand even further, Milan told me the 12:1 motor in his car (that went 9.34 in the 1/4) can run on pump gas. It's all about the BMEP. If we want to have a BMEP discussion, Fordboy628 has excel sheets full of them.

HWYSTR455

I give. If you want to use certain logic regarding what static CR to run, then explain why you wouldn't want to be really safe, and just go 8.5, or 7.5 for that matter. Why not?

If someone is going to take the sole advice of people on the 'internet' on how to build their' engine, then that's their' business. But I strongly suggest one talks to an engine builder for recommendations, it's just common sense.

I've built over 60 different engines in my time, I know what works for me. I share my experiences for others to have an optional source of info, hopefully learn something from them, and avoid some of the mistakes I've made. Why do I share? Love of the hobby. There's nothing out there that says you have to take any info I provide as law, and if you want, just ignore me.

You can look at any of my install threads and see I'm fairly thorough, and provide useful info. And all are welcome to share their' opinions on what I post.

.

67 Cutlass Freak

Crickets ^^^^^
Mr 80 Rocket, I have not had the opportunity to measure the runner volume or CSA on the Pro Comps or the Edelbrocks, but according to Speedmaster's website they share the same runner volume of 188 CCs.

wr1970

I like your agenda! Trying to be a honest guy who shares his experiences. In a discussion you can disagree and still respect what is being said. You are to be commended for making it clear your love of the hobby is what is important to you. 60 engines is quite a few.

80 Rocket

You are getting a bit defensive. I am simply sharing some information from a very accomplished cylinder head specialist.

If someone wants to talk to a builder, they can contact me . I work with a group of very talented people. TnT Racing Engines in Gurnee, IL.

Again, I didn't mean to put you down......I was simply bringing some thoughts to the table and what I believe to be a better way of looking at an engines compression characteristics. I have seen your advice in past threads and find you to be very thorough and helpful.

As you, I post information for the love of the hobby. I have sheets full of cylinder head data I will share soon once I get more flow testing done.

HWYSTR455

T&T are a good group of folks, and have heard nothing but positive stuff about Tommy. You are lucky to have that at your finger tips.

.

80 Rocket

Yes, I understand how lucky I am to be in this position. I like to think that 13 years of dedication is paying off, but there still was luck that came into play. I got hooked up with Tommy at my local dragstrip I manage. He put out a Facebook message saying he was looking for machinists last year. I responded but he didn't seem interested. About 2 weeks later he came to do some testing down the track I prepped and reset the x275 radial record at our track (4.78 in the 1/8). The next day I was at his shop.

Not sure if you have heard of Chuck Samuels of Fast Times as well? He used to be pretty big into Olds about 20 years ago and built some big time Olds stuff. He works by us as well.

wr1970

There you have it some guys have all the luck. You still had something that made the shop owner decide to hire you! Don congrats on all you have done.

slade69

cutlassefi

All the bearing shells have extra clearance built into them for the rear main. Leave it alone, it's designed that way because it's so wide. But if you must, Sealed power makes a .001 under bearing shell for the small blocks I believe.
Don't use that rod, use the one with the 7/16 bolt and with that you don't need the ARP2000. That's a waste for your build.

80Rocket yes the entry way of the Procomp is a little smaller as cast at the pushrod pinch point than the Edelbrock is. Hmmm I thought you said you've seen the Procomp heads first hand?

80 Rocket

I'm truly flattered you think I am that talented that I can look at a port and know the runner volume without actually measuring. However, I am not that good. Surely you understand the difference between inspecting a head and actually blueprinting one.

I figured I would ask you what the runner volume was of an as-cast Pro Comp since you have had your hands on many. But, I understand you don't really do much with them except bolt them on, correct?

Having a small pushrod pinch simply means you locally speed up the air. Why would you want to speed up air tremendously right before it has to make that turn in the port? See my point now?

cutlassefi

I've measured the pinch point with dividers, it's smaller than an Edelbrock. We've also gone thru various points throughout the port, they're smaller overall than an out of the box Edelbrock. But we never cc'd the runners on either one though.

And based on the set of Procomps that I have that were ported by Champion, they had to remove more material than a comparable set of Edelbrocks. Plus the low lift flow is a little better on the Procomps. Yes, I know that could be a lot of things but it all falls into place, at least on the surface.
But based on the flow numbers I've seen on both stock and ported Edelbrocks and Procomps, I wouldn't think twice about putting either one on virtually any small block.

80 Rocket

Dave and I measure with telescoping gauges and figure out the CSA. Checking the runner volume of cylinder heads is an important aspect of designing an engine because with that data, and port centerline length, you can establish your average CSA which Pipemax can assist with what will work best with your engine. Every head that we do has quite the sheet full of useful (or useless ) data.

When I was at work today, I noticed a Grand National engine on a stand. The fuel rails (it was fuel injected) said "Champion Race Heads" and the heads were aluminum. I assume this is your guy down in Florida, stuff looked good.

76olds

I hope you were using starrett or mitutoyo telescopic gauges. If you were using the chinese gauges they tend to stick and give false readings, even worse when measuring with a china mic afterwards. That could be where the useful and useless info plays a part

80 Rocket

Thanks for the tip. I'm a Mitutoyo kinda guy myself.

80 Rocket

I really do have to ask now.....for measuring the pushrod pinch in a cast port, what is your method of checking? And how do you take into account the radius in the 4 corners?

Usually when someone wants to become helpful, they back up their suggestions with solid procedures. It is very important for me to be very accurate with my measurements. When you are working with ports in a cylinder head, it is always a challenge.

One of the hardest things to do is measure the port centerline length. What is your method? Would you use Starret or Mitutoyo to measure that?