MYSTERY Ported Heads

LONG POST INCOMING:

So, I picked up some "zzp stage two" heads a while back that have two bent valves, but the dude gave them to me for cheap with the gen v and n* I got.

I sent some pictures to zzp and they said they're not their heads.

They are currently at an engine rebuild shop for cleaning, inspecting, and resurfacing. They're crack free and cleaned up nice, but he was having trouble tracking down the valves. He also said the port work looks incredible.

The valves are 1.9" intake and 1.57" exhaust. The only place I could find selling these valves was Intense. These are also the valves used in the Intense stage 3 heads, which leads me to believe that might be what these actually are.

Intense says they are machined to handle .600 valve lift; is there any way to measure this to verify? Also, if the springs are the 130# that Intense puts on their heads, will I basically not be able to run them without a double roller? And will I need rocker shims or shorter pushrods like with zzps?

Assuming they ARE the stage 3 heads, would I be a complete idiot to not buy a massive cam and sell my rockers? Or would doing something like a vs cam in addition to my rockers make sense?

I'll be calling intense on Monday to see what they can tell me, but any help from any of you guys would be greatly appreciated! I'll post pictures when I get the heads back from the shop.

Thanks in advance!

If you have 130# springs you will want a double roller chain. It's very appropriate to run these heads with a very large cam, that's the whole point. See what cam Intense recommends to work with the heads. What rockers are on them? If you are going to have a big cam and 130# springs, you will also need good roller rockers, adjustable pushrods and the like. If you don't know what you are doing with the valvetrain, ask the machine shop if they have somebody who does. You don't want to assemble something like that carelessly. The valvetrain if left stock or just rockers is pretty robust, but when you get into the very high lift setups, you need to pay a lot of attention to details.

If you are going to street drive this car, this head/cam combo might not be advisable. Can you drive it on the street? Sure, but it will vibrate and have a crappy idle. Also, if you run this head/cam combo, get big headers and have a pro tune it on a dyno.

Thanks for the reply! The heads had no rockers when I got them. I was planning on swapping my 1.9s onto them and calling it good, but if the heads are built for a ton of lift, that doesn't really make a lot of sense. As far as other mods to go along with the heads, I have the gen v/n* and I'll be keeping my zzp headers and everything else. I also sold my intercooler in favor or buying bigger injectors and a pump to run e85, but if it ends up making more sense to spend the money on a timing chain and cam I'll do that.

The dude I bought the heads and gen v and stuff from also gave me some comp oer lifters. I think he was being deployed or something, so he was just getting rid of stuff. I'm not sure if I should run those or not.

I do DD the car, but only during the summer months, and I'm 20, so loud and vibrate-y and crappy idle doesn't bother me a whole lot.

A shot a message to intense asking about the heads, and I'll swing by the shop Monday or Tuesday to take pictures and see if the rebuilder can check the clearance. Assuming they are machined to handle .600 valve lift, I could run a w-body store stage 1 cam with my rockers and be fine. The wbs cam has longer duration, which my rockers don't give me, but less lift than the Intense or vs cam, so the lift would be ok, even with my 1.9s. In my mind, that translates to smoother idle and possibly better mpgs, but I have no idea. I asked intense about that as well, and what cam they would recommend.

I would highly recommend just getting a big cam under those heads and sell your 1.9's. Xpz is very streetable and I have no driveability complaints with my IS3. You will make way more peak power than with a mild cam and a bunch of extra lift it wasn't designed for (the cam). I was reading a little while ago about somebody who did back to back dyno testing with the IS3 blower cam with stock rockers, 1.6rollers, and 1.7rollers. The 1.6 roller rockers made significantly less power than the stock and the 1.7 roller rockers were only slightly better than the 1.6 rollers - still less than stock. I'll find the thread if you want to read through it.

turtleman wrote:

I would highly recommend just getting a big cam under those heads and sell your 1.9's. Xpz is very streetable and I have no driveability complaints with my IS3. You will make way more peak power than with a mild cam and a bunch of extra lift it wasn't designed for (the cam). I was reading a little while ago about somebody who did back to back dyno testing with the IS3 blower cam with stock rockers, 1.6rollers, and 1.7rollers. The 1.6 roller rockers made significantly less power than the stock and the 1.7 roller rockers were only slightly better than the 1.6 rollers - still less than stock. I'll find the thread if you want to read through it.

I'll take your word for it! I was kind of hoping you'd comment on this haha. So if you had it to do over again, would you go for the xpz rather than is3? I have a low mile n/a engine sitting around, so I could have a non-intercooled version of your setup basically!

I'm happy with the IS3. It has some real top end bite - just loves all the rpm you can spin it. According to that guy's test, I'm short-changed on power too because I've been running 1.6 yella terra rockers since day one. I did build Manuel's engine with an xpz with nice home ported heads with intense valves and stuff. I got a good impression from that too - it felt strong. I didn't really get into full like 1/4mi pulls with it though - I just tuned all the stuff we did to drive safely so he could take it to PRJ for a thorough tune. So to answer your question, I'd honestly do what I did which is get whichever cam is cheaper to attain at the time haha. The xpz is kinda more clever in terms of engineering and kinda seems to give you everything so it's hard not to say just get that cam. IS3/4 is an obvious recipe of positive exhaust flow and lots of it. It has more duration and overlap so generally that means lower fuel economy, comparatively lower power/driveability in low rpm, and lumpier although like I said I haven't personally found these to be a problem aside from mpg in the city.
Also don't use the OE-R lifters - it just makes it way more critical setting up the valvetrain since you have very little preload range and even when you do get them right, they are still known to be noisy. Stock is just fine.

Thanks! I was thinking I can probably get a little bit of cash for the oe-rs to put toward the cam and such. Are stock rockers known to cause damage to valves or anything? I'd be willing to sacrifice a bit of power to make it a more reliable build.

Is buying a used cam and pushrods sketchy? I found a dude selling an xpz with pushrods for $350. It seems like something I might just want to get new though. Would you mind if I shoot you some pms in the future after I figure out if the heads are in fact the is3s?

I haven't been around as long or seen as much as some others but I have never heard of anyone actually having any problem related to the standard rocker arms and valve stems. Plus the Intense valves are harder than the OEM. They are designed for wear resistance there. If anything the bigger concern would be the life of your valve guides especially if the heads were rebuilt with insert-style guides but regardless, I wouldn't sweat it.
Used cam and pushrods should be fine used. There would have to have been a serious event of failure for there to be any wear/damage that would be a problem. Pushrods generally come along with the xpz cam just because it requires two different pushrod lengths. I'd just confirm with the seller everything's in perfect condition and whatnot so if there's something stupid like they scratched a bearing surface during removal or something they mention it.
Yeah go head and pm me. I'll help with whatever I can.

Awesome. Thanks for helping me out! I'm going to post pictures up on Tuesday of the heads!

Any updates from Intense on these?

Not yet! They didn't email me back today. I am going to send them pictures of them tomorrow and see if that gets me anywhere!

Talked to intense on my lunch break. The dude (John?) told me that he can't really verify if the heads are theirs by pictures. He made it seem like kind of a liability issue. Like if he tells me they ARE stage 3 heads and I try to run a big cam and destroy my engine because they aren't, he wouldn't want to be responsible. That's understandable.

He did tell me to look for bronze valve guides, 130# springs, cnc work on the runners (he said if I couldn't tell that my rebuilder should be able to), .600 clearance, 1.80" installed sting height, and stock length valves.

My rebuilder told me the valves were 4.710", and the dude from intense told me that stock valves are 4.750". I think I'm going to have my rebuilder remeasure to be sure. Can anyone verify stock valve length?

When I got my is3's rebuilt, my builder scribbled some notes down about my valves cause we decided to replace 6 of em. I'll look for that when I get home. Email me pics too. MFNcody@live.com

So it's looking like no good news! I went and took a look at  my heads, and there are no brass guides, and my rebuilder said the port work looks very, very minimal, but it's hard to really tell when you don't know exactly what stock looks like.

I just can't get my head around who would have a valve job done of these heads and put oversized, stainless valves in it if they weren't going to port them and run a big cam.

He measured the spring at 1.80", and he said it was like 70lbs...

I really don't know what to think of the whole situation. I mean, even just the oversized valves and (possible) minor porting would have performance gains enough to make it worth my while, right?



And awesome, thanks!

If you have the heads flowed by a shop, they may be able to tell you if they are better than stock. Ask zzp what stock heads flow.

Here are some pictures. Feel free to offer knowledge, or just roast me for buying hack-job heads
Didn't spend much on them at though, so it's all good.





















Not sure if these are l67 or ls1 retainers.




Cool lookin' bent valves.

There were definitely some no-name home ported heads floating around the 3800 world. Just have your machine shop fix em up right and try to make the porting somewhat even across all the heads, and you should be good to go.

I helped a guy buy some a few years ago, was driving through PA and stopped to pick them up. That 'home porting' job looked a lot cleaner than this one, but without a flow bench it's really impossible to compare. You can't compare porting without flow testing.

At this point I would just go with whatever is going to work without a lot of machining and consider them "Stage 1" heads, and keep your build somewhere in the mid/agressive range without going full on. If you want to build a full-on stage 3 type motor, you are going to need one helluva transmission build to back it up anyway.

The heads in my car have "Some Porting" but nobody can say how much. With the VS cam it runs fantastic. A larger cam will really make it pull, no matter how good/bad the porting was. Only many 1/4 miles and dyno pulls will tell you how small a pulley you can use, or how much fuel you need... etc.

Only thing I can really say is they aren't IS3/4 heads. Just have your builder set them up for whichever cam you want but I wouldn't take any chances on the valve springs. If you can't positively verify what lb they are at the 1.800 install height, make sure to get what you need for the cam and make sure the builder clearances the valve guide face for proper clearance at full lift

Oh I forgot to check for my notes last night. I'll check tonight or in the morning

That was pretty much my plan. I mean, the fact that they have bigger valves and some sort of porting makes me believe that no matter what they will be at least a small upgrade.

I think I'll just slap my 1.9s on there and call it good.

The thing that's really stumping me is that my rebuilder is saying the valves are 4.710", and I've been told that stock 3800 valves are 4.750". I can't find 1.57" or 1.9" valves that are 4.710".

Why would the valves be shorter? Maybe he has some crappy calipers? Lol

He said it would be fine, but what do you guys think of buying the Manley valves that intense sells and grinding that little bit off?

As far as springs, I think I'll just take the 90#s off my current heads since I know exactly what they are.

Well one of the old valves was bent so hmmmm.......

It would leave the pushrods loose if they are too short. Have him make sure the lifter preload is okay, you might need adjustable pushrods to make up the difference. I wonder what the reason is behind the shorter valves.

In my opinion valvetrain is one of the most important parts of the engine build. It sounds like this guy knows what he is doing, but be sure the rotating assembly is checked out properly before you start it up. Talk about why you would want a shorter than stock valve length. It's possible the heads were milled down to make higher compression chambers, resulting in the need for shorter valves... ???

Milled heads does make a lot of sense as to why they'd be shorter. The valves are bent because they got kissed by a piston when the motor exploded, which is why the heads were pulled. He checked and said they aren't warped or cracked.

As far as getting the valve situation resolved, I see two possibilities. I could either A. Buy two Manley valves and have him grind them a bit (still not sure if I like this idea), or B. Replace all of the valves with new stock length valves (also not sure if this would have any ill effects.)

Here's the notes my guy took off my IS3 valves since we were looking to replace the intakes. These are what came in my IS3 heads.

INTAKE
4.725 length
1.900 head
0.313 stem
0.175 tip

EXHAUST
4.718 length
1.610 head
0.313 stem
0.175 tip

Also there's a note on my invoice that the replacement Intense intake valves are .028" taller than the originals.

So mine aren't ridiculously short by any means...

What is the "tip" measure?

And 1.610" exhaust is huge! Zzp says on their website that even 1.59" is so big that they have to grind out the entire factory hardened valve seat, and that's not really a good thing. Is that a concern of yours at all?