Hi all.. I recently purchased a 1971 Delta 88 that has a 455 with "Mondello" sourced Procomp heads on it. I am aware of the difference between Bernard Mondello and Mondello Performance, but unfortunately the previous owner could not elaborate on or verify which source the heads came from. So first, a question: are there any markings or other indicators I may be able to find on my heads to indicate where they came from?

Here's my concern... I am aware of the quality issues with Procomp heads on a variety of different engine families. I have never run a set myself and would not choose to purchase chinese heads from any source over a higher quality American product. But, since these heads were already installed on this running engine, my question is whether or not I should continue to run them. I am not concerned about max power or flow numbers, as I will not be racing this car at all, just street cruising with some street stomping, but no serious abuse. I do not care whether or not they perform on par with any other set of heads in terms of power, as my intention with a full size convertible is mostly cruising.

If the downside risk of running them in a primarily street context involves real risk of serious engine damage due to failure, I obviously don't want to take that chance. But if the issues aren't that serious and are more to do with performance or longevity, I will not be as concerned. This engine seems to run fine now without any particular issues, apart from being cammed too aggressively for a big cruiser with highway gears. I will be addressing that. Just wondering if I should give serious thought to switching out the heads as well, as my primary interest is in real world street drivability and reliability.

Does anyone have any experience actually running Procomp heads on the street for a bunch of miles? Any insight into common failures or issues with them? Thanks all!

 

My heads came from Bernard, they are engraved with B.M.R.E. (Bernard Mondello Racing Enterprise) and a date. They were fine for 30k miles, and I would run them again.

 

I guess that means they aren’t from Bernard, as these are the only engravings I see anywhere (without pulling the valve covers off):

 

I’ve never heard of a set failing…
but who knows what kind of components they were built with.
Pull the VC’s and see what you find.
-peter

 

I believe that heads themselves can be OK (unless there is a flaw in a casting and you have leaks or the like). The bigger problem is the valves, springs, retainers and any other "hardware" (not sure if that includes guides, seats etc...). If they are still the original Chinese parts then they can fail and cause massive problems/damage. Someone with more experience might be able to tell you how to tell if they have been replaced. Or at least they can tell you what you should replace if you decide to rebuild them.

 

Since the engine is installed snd running, and you have put some miles on it, I’m betting your fine. I have heard of casting issues, I would think a problem like that would show up fairly early.

As others mentioned, the valves,springs, etc used in the aftermarket heads are hit and miss in quality. Who knows what Mondello installed? And with Lynn’s well known business ethics, chances are good whatever you paid for isn’t what was installed.

 

^^^This will tell you which Mondello did the heads!^^^.

I bought a set of unused but never run ProComp heads from an individual who ran out of steam and never built his car. I called Bernard to get the details on these heads before I bought them. Bernard buys the heads as bare castings and builds them with quality parts with the correct clearances. I asked my machine shop to check out the heads when I built my stroker engine. The machinist disassembled the heads to install new valve springs and set the open/closed spring pressures; he also checked the valve seats, guides and clearances, etc. and found nothing wrong with any of this. If your heads have the B.M.R.E. stamp you should have nothing to worry about.

Rodney

 

I’ve run and sold dozens of these, no issues except I do replace the springs, retainers and locks. The main reason for that is the spring “rates” aren’t right. The flat tappet springs are little too aggressive and their roller springs aren’t aggressive enough.
However if you don’t address the fact that the intake runner entry isn’t great out of the box, or the fact that the chambers have never been 77cc’s (they’re really about 82) then you won’t see much benefit over a good set of irons.

 

They were already installed on the engine in the car I bought. I have not put any miles on them. I have no idea how many miles may be on them, but they look pretty fresh relative to the engine block.

They do not have any BMRE stamp that I can see. I guess that's not a good sign. I am unconcerned about power as this car will be a cruiser. I do want it to run well, so I will be changing the camshaft at a minimum to a more streetable grind to work with the 2.73 gears, but I'm sure I will be fine with whatever power it ends up making. My concern is primarily with quality control, and whether or not these heads are likely to drop a valve and ruin what seems to be a good short block as well.

Bottom line for me is that if these heads come off for any reason, I'll be putting a set of stock heads back on and sell these. The only reason I might leave them for now is because they're already installed and running. But they aren't the direction I would go with this car if I were starting over from scratch, and they will definitely come off later down the road when I decide to restore this car. Only reason I'm considering leaving them for now is because I just want to drive it mostly as-is for the time being.

Edit: for reference, the bone stock original 455 in my '75 is fine for my cruiser purposes, and I think it's around 220hp, so you see where I'm coming from in the power department.

 

Not sure why you would even consider doing that ???? By the time you find a decent set of stock heads and have them rebuilt properly you will almost certainly spend more money than you will ever get by selling the Pro Comps. The Pro Comp heads are fine. Leave things alone.

 

If you just read the rest of that paragraph I explained why. I would rather have this car all stock, including under the hood. When I restore it later I will be taking these heads off regardless in favor of a good set of factory heads. Not necessarily correct original heads for this car, but stock Oldsmobile heads anyway.

 

I would have to agree.

Stock is boring. Unless it’s a collectible/survivor/rare car, leave it alone. It’s a full sized Olds, so rare and collectible is out, and since Mondello has already been into the engine, survivor car it isn’t. The aftermarket heads are already pump gas ready, they are on the car, and are a easy 40-50hp bolt on power gain.

 

With all due respect do you have proof of this claim? Dyno sheet? Time slip?
The reality is unless the intake entry has been addressed they’re not worth anywhere near that power gain, not even close.
Please refer to the comparison builds I posted on here a couple of months ago. The 455 posted only made 420hp with a decent Hyd roller, Torker and a good carb but out of the box Procomps. They don’t flow much, if any better out of the box than a set of similarly valved irons. I’ve made the same or more hp with a decent set of irons in an otherwise identical combination.

 

OP asks for advice regarding reliability of aftermarket heads. OP gets advice from two very experienced OLDS engines pros and experienced hobbyists. OP then argues with said advice and adds a desire for under hood originality (even though the car is equipped with headers). Not sure what the OP is trying to accomplish except pushing back against the advice and opinions he asked for. Phew! Bottom line, if you want you to disassemble a good running engine go ahead. If you want to argue take it up with your wife.

 

I guess literacy isn’t the order of the day. I made it abundantly clear in my original post that I am unconcerned about power. Then I get responses from people telling me I should keep them because they will make more power. Makes sense, right? Then a well respected builder comes along and corrects them for their false power claims, thus further nullifying their pointless posts.

I am concerned about the quality of the heads and whether or not they will fail on me, causing more damage. Since my engine has NOT been touched by the Mondello that matters, that seems to confirm that my heads may be of inconsistent build quality. That’s the info I was looking for. Not info about power, as I made it very clear that was not my concern.

If you think I’m the one arguing, you aren’t reading my posts. But hey, carry on if that makes you happy.

I didn’t come here to bicker or argue. But as so often happens on forums, people don’t read and they project on others what they would do with their car, regardless of what is important to the person asking the question. I made clear what is important to me, and further clarified it when someone seemed not to get it. And then people STILL wanted to talk about power when I made it absolutely clear that I’m not concerned about it. If that’s arguing, fine, let’s argue.

 

The bottom line is do what the voices in your head tell you to do. Your car, your money, your happiness. With forums, never ask a question that you know you won't like the answer to. Just because Mondello has not had their hand on your heads does not necessarily mean they will fail.

 

I understand that. But I would feel better about running them if they had actually been from Bernard or cutlassefi, as I know they are trusted names in this business. As you may recall, I asked in my original post if there was a way to confirm their origin, and I was provided that. Now that I know they are not in fact Bernard Mondello heads, I have something more to go on.

I haven’t taken the heads off yet and have not made any decisions yet.. just acquiring information to help me make a decision. The next step is to pull a valve cover to see what I have under there. Maybe I’ll see something else that gives me confidence or takes it away, I don’t know. But all I’m doing right now is acquiring info, since I don’t yet have enough to make a decision.

 

^^^^ x2

 

Mondello (Lynn) carries a number of rocker arms, pushrod sizes, etc. Just because his name is on the heads I don't think I'd automatically assume they're going to fail. Pull the valve covers and see what you've got. It'll also maybe give you a chance to evaluate the health of the components. He's got a pretty bad reputation on this site but even a broken clock is right twice a day.

 

[QUOTE=oldcutlass;1399174] With forums, never ask a question that you know you won't like the answer to./QUOTE]

+1! And keep the snarky comments to yourself... Disgraceful. I'm going to make some pop corn.

 

You guys crack me up. Several of you understood what I was asking and provided good relevant info and suggestions which I appreciate it. To the ones who think I'm being snarky.. maybe read a little better next time and stay on topic and you won't get pushback.

That's an unfortunate problem with internet forums.. people don't read or understand what they're reading, but then make irrelevant commentary anyway, then get upset when they get called on it. Makes no difference to me, there's always a few of those on every forum and they're easy to spot. I'm going to keep doing what I'm doing.

 

I don’t have a dyno, I don’t have nearly the experience with aftermarket heads to scientifically prove my “claim”. I have heard from numerous people the aftermarket heads are a big improvement in power over cast iron.

What I am absolutely sure of is the improvement on my car. I had a pair of big valve C heads, the car ran consistent 8:30s (occasionally high 8.20s) 1/8 mile. I put a pair of Edlebrock heads on (this was the first year they were available, I’m guessing 1999-2000?) very first day at the track went 7.91 and about 4mph faster. I made no other changes to the car other than what was required to install the heads.

Maybe I had a really crappy pair of C heads? I don’t know. All I am absolutely sure of is they did pick up about 4 tenths with zero changes other than the heads.

 

I don’t doubt what you’re saying here but you’re comparing apples and oranges. Compare your Edelbrocks out of the box to the Procomps/Speedmasters in the same condition and you’ll see what I mean.

 

i thought the Procomps were Chinese copies of the Edelbrock heads? I assume you mean the airflow capabilities of the Procomps are inferior to the edelbrock?

 

Kind of, and yes. They don’t flow the same as Gen 1 Edelbrocks because of the horrible intake entry. In addition the chambers aren’t 77cc as advertised like the Edelbrocks are. They avg about 82. So again if installed out of the box, they WILL NOT perform as well as the Edelbrocks.

 

I did not know that. Another good reason to support American manufacturing. Most people who buy aftermarket heads do so for the performance improvement. If you need do a bunch of machine work to the Chinese crap to equal the airflow capabilities of the Edelbrock heads then the cost savings is a wash.

 

Correct. But as compared to the first Gen Edelbrocks, the Procomps/Speedmasters are a bit thicker here and there.

 

Do you have flow #’s for the Gen 1 Ebrocks and pro comps from the same bench?

can you post intake numbers if you do