Ok, heres the deal. Sat me and a friend did some work on the car. Changed all the fluids (diff, tranny, oil, coolant), replaced the water pump, welded up the exhaust and gutted the cat. All went well. Took the car out sat night, it was awesome.... at first. after about half hour or 45 min of driving we stopped to get gas, about 2 miles after getting gas all of a sudden the car is running for crap. It feels like the timing is way retarded or missing, theres no power and it sounds really nasty when you get on the gas at all.

So here what I all though of. First the gas was only 92 octane and I usualy run 93. not much difference but???

Next I found one plug wire that had leaned up on the header on melted, fixed that. Checked all the plug wires with a test light, they all fire very good now.

Checked timing, it was down to 8 deg advance. I moved it back up to 12 where I had it originaly.

So now its running better, but still not quite right, still feels like its missing a little?? or its still retarded??? Any ideas on what to check? I havent yet but Im going to check the plugs after work tonight. What should I look for?? Please help, this car keeps teasing me by giving me some awesome performance then doing something wierd like this and running crappy.

 

Unless you're running high compression, you're wasting your money on 93 octane and even 92.
I say check the plug wire again. I recently bought wire looms and heat sleeving and didn't order enough heat sleeving. Just the other day one of the unprotected wires got burnt. Now I have more heat sleeving coming today.

 

I was told that the L98 runs 9.5 : 1 compression stock, and when I had it rebuilt I had forged pistons put in. The guy that rebuilt it said that the compression would be slightly higher so it would be best to run the 93 octane.

what kind of heat sleaving do you use? I had one of those big metal mesh, protector boots on and it still melted.

 

I bought the Spectre Heat Sleeving in the Jegs catalog. Protects up to 1400*. Only $12 for 10' but you need 2 packs.

 

did you disconnect the EST wire when you set the timing? i don't run tpi so i'm not sure where it's at but i know you have to disconnect it

mark,
is the spectre sleeving big enough to cover the boots as well? the boot-specific insulation is like $40 for 10" so i'd rather get the spectre sleeves if they'll work

 

double post

 

Ukraine,

Yeah I disconnected the wire while timing, then reconnected it.

I pulled the plug on the wire that was fried, sure enough the plug was pretty fouled up, pretty black. And after reading some of the other posts on spark plugs I went out and bought a new set of regular bosch platinum to replace the +4's that I had. It seemed to be the consensous that they arent that good. I think Im going to leave them at the stock gap for now, and I will try and put them in tomorrow after work.

Mark,

I plan on getting some of that heat sleaving, looks like a good deal for the money. beats the hell out of buying the protective boots for like $60 a set.

Ill Post it up here when I see if it solves the problems.

Thanks again.

 

The sleeving only fit 7-9mm. Though if you wanted you could cut it down the middle, and just wrap a few layers around it to cover it.

I had to cut it down the middle anyway since the boots were on the wires already, and just used some electrical tape to keep it in tact.

 

check the heat shield from MSD...only need one PKG. it works great on mine...

 

Ok guys, I found out whats wrong with the car, and it isnt good.

The #6 and #8 cylinders arent firing. The plug is firing but there is nothing going on in the cylinder. So either my crap @ss stock pressed in rocker studs pulled out and the valves arent working, or the head gasket blew. So pretty much either way I will be pulling the heads off. So when I do Im going to take them to the race shop and have the threaded studs put in. If I have the money at the time, I will probably upgrade to a set of 1.6 steel roller rockers, and new valve springs.(not sure yet) Oh well, It could be worse.

 

did you pull a valve cover to verify that your valves aren't working on 6 and 8? if you pulled a stud it'll either be a lot higher than the others or it fell out so either way it should be easy to tell. did you check if those injectors are firing? you can get noid lights from most stores that will tell you if they are.

 

a friend of a friend helped me out with this one (hes a car genious). We pulled all the injector wires one at a time, you could hear it change cause of the miss when you unplugged them, accept for on #6 and #8 there was no change. We checked both of them with a mulitmeter and they were ok. And just by smelling the exhaust you can tell there is extra fuel in it. I havent pulled the valve covers yet, going to do it this weekend, for now the car is just gonna sit in the garage.

Pretty much what it comes down to is, I know the spark plug is firing in both, I know the injectors are working in both, but they arent firing, so either the valves arent opening, or there is no compression. And like I said either way Im going to end up pulling the heads.

 

You might take a look at tapping those heads yourself....Its not that difficult to do...and save some$$. Ibelieve there are some tech articals about it here.

 

I looked at the tech articles, and I though about it, but personaly Im not comfortable with doing it that way. To much chance that they wont be straight, or that some of the metal shavings could find there way into the motor where they shouldnt be. so Im thinking its worth the extra time to take them in and as far as the $$ the race shop quoted me $60 plus the cost of the studs to machine/tap the heads. Thanks for the idea though.

 

sounds more than fair, hope it woks out for ya...

 

8:00 am Sat. Girlfriend wakes me up for something, what I dont know, so being that Im up I decided to go work on the car. Finaly got the time to go out and take a look at the motor. Took the valve covers off and sure enough the stud for the intake valve on #6 had pull up about half an inch and the rocker was just flopping in the breeze. I looked everything over and from what I can see, no damage.

9:00 sat down had breakfast decided I would pull the engine today being that its still early and Im not doing anything else, so I went and got my buddy's engine stand and hoist.

11:00 Let the games begin. Being that this is now the 3rd time Ive pulled my engine it went quite well. Other than not having any help it wasn't going to bad. Oh yeah and the stupid ichy hands from the crap in the header rap. I hate that so much.

10:00 pm engine is out, and on the stand. after looking at it closer I notice that other than the one stud that pulled out on #6 there are at least 5 other studs that have started to pull out and are noticeably higher than the rest.

Not bad for one day all by myself. Anyways tomorrow Im going to try and take pictures, then pull the heads and get them ready to take in to the shop on monday.

 

Ok heres the pictures of the motor, you can see the stud that pulled out. I have another question to. Is all that black crap on the top of the pistons ok, bad, what is it?

 

PK,

I've been watching this one for a while. Several things come to mind after viewing the photos more closely.

First, since the heads are off, you can brush away the carbon on the piston tops with a die grinder and wire cup. Or leave it there, since it isn't making a lot of difference at this point. You may be running a little rich, since the deposits are black instead of brown/tan.

Second, you should have had some valve train noise accompanying the stud failure, and that should have been a major clue.

Third, since there was valve train failure, inspect the push rods closely for scuffing, bending, and hammering on the tips. (More about the push rods later.) Also check the lifter rollers, axles, and cam lobes for signs of pounding.

Next, since the heads are off, for Heaven's sake, get rid of those damned exhaust valve rotators and shim the springs to the corerct height. Their extra mass is killing your RPMs and pounding the valve train unnecessarily. You can get .300" cup spacers for about $20.00.

Another suggestion would be to replace the stock rockers with at least a self aligning roller-tipped replacement. Most aftermarket stamped rockers are at least stronger and more reliable than the stock parts. Since you're machining for screwed studs, you could have them go deeper and install guide plates to use non-SA rockers if you choose. Of course, that will necessitate hardened push rods. But at least have the heads machined for the plates and shimmed if necessary, so you'll have the oprion later.

You may also want to machine the guide bosses for positive Teflon valve seals, so you can eliminate the need for the spring oil shields and their extra mass as well.

You may want to evaluate the valve springs you're using. As long as the heads are under the mill, enlarging the spring pockets shouldn't be prohibitively expensive if it is necessary.

I hate to spend all you money that way, but now's the time to do it if you're ever going to. Then again, you're getting pretty good at removing the engine in short order.

 

I was planning on cleaning everything up like you said before I put it all back together. The stuff on the pistons pretty much can be wiped off with a rag, its pretty gooie.

As far as the noise from the valves, none whats so ever. When the rocker came off like it is in the picture it the pushrod jumped off the lifter and it was just sitting in there on an angle, so it was pretty much like it wasnt there. I checked all the rods and rockers, no bends, no marks nothing. Everything seems fine.

Exhaust valve rotators???? Sorry Im still new at all this.

As far as the rockers go, I am planning on having the heads machined for the studs and the guides, I was told that I dont need the guides but they wont hurt and I may need them later. Eventualy I want to put a set of the comp cams magnum roller tip rockers on there.

What will I gain from enlarging the spring pockets?? (once again Im still new at this)

More info that I found out today. The guy that built my engine 2 years ago when I asked to have the heads ported and polished I got a 3 angle valve job. I wanted a cam that had some more power and kinda mean with out being unstreetable, what I got a comp cam high energy cam which I find out today is almost identical to stock. This is just a little more stuff to add to the list of things that the guy screwed me over on. And the better business buero will be getting one long letter soon.

So the new plan is Im broke, so Im just having the studs done now. droping the motor back in. Then this winter when hopefully I have more money to work with Im going to take it back out, and do it all at one time. I talked to some guy at comp cams and they said that if I were to buy everything (cam, lifters, rods, rockers....) all at one time they could give me a pretty good deal on the package. At that time Im either gonna have the heads ported/polished and bigger valves put in, or Im just going to find a set of aftermarket heads (will need help with which ones to get).

Well I think thats about it, for now. Any more suggestions and what not would help alot, thanks.

Kevin

 

PK,

A valve rotator is the thick spacer on top of the valve spring. In your photo, it appears that the exhaust valves all have rotators, which is the way they came from the factory. They add dead weight to the valve train, take up energy to move, tend to cause valve float, and even when they work properly don't really add to the life of the valves. The fact that you have rotators indicates to me that you are still using the stock valve springs as well, since no self-respecting builder would reinstall the rotators on good replacement springs.

You would need to remove the rotators and get new spring retainers to take their place. Fortunately, GMPP (and your local dealer) have replacements designed for the LT1/LT4 engines that are lightweight and relatively inexpensive, and fit your 350 just fine:

Valve spring retainers, GMPP 12495492 - LT4 lightweight $15.54 per set of 16;

Valve retainer key set, GMPP 12495503 - 10° locks $ 6.83 per full set of 32;

Valve springs, GMPP 12495494 - Oval wire LT4 springs $35.95 per full set of 16;

These springs are designed to install at the "normal" height of 1.700-1.710". They are slightly larger in diameter than your stock springs, but may fit the stock spring pockets without machining (some do, some don't, depending on the individual head). These springs are made of an oval wire to prevent coil bind at stock installed heights and allow for lifts to 0.525".

As for your cam, exactly what Comp grind is it? I seriously doubt that the HE cam is only slightly better than the stock cam. Get me the part number and I can show you the differences.

Incidentally, if you need a set of screwed rocker studs and like the idea of one-stop shopping, GMPP also has those, as well as the gaskets you might need. Actually, I think I have a spare set of GMPP studs floating around. You can have them if you want to drive 1½ hours, but you'll probably spend more in fuel than they're worth, since you can order at set at the dealer for about $15.00.

 

The speed shop just called, my heads should be ready by the time I get off work tonight. I just had them do the studs, and they had them in stock so I just go them there. I think Im going to run down to the dealership after I pick up the heads and get the spring retainers and the keys. If I can I plan on sticking with the springs that I have, will that work ok?

Oh yeah the cam is a Comp Cam 08-302-8 here is a link to the spec page: http://www.compcams.com/information/...umber=08-302-8

As far as the gaskets go I think Im going to get them at the speed shop, they have pretty much everything there and they are probably cheeper than the dealership.

With any amount of luck I will have the car back on the road by the end of the weekend.

 

PK,

That's NOT too much cam for a 350/358. The LSA may be a little tight on a TPI, but the MAF is going to be somewhat forgiving on that.

However, with those lifts (and ramps) you absolutely, positively, should NOT use the stock valve springs. I'm a little surprized that you haven't broken one yet. I'll bet you a bottle/glass your favorite beverage that if you have the shop test the spring pressures, they're WAY below specs from fatigue. With that cam, you'll need at least 110 lbs. of closed seat pressure and around 200lb/inch spring rate at a minimum. I'd also strongly advise the valve guide boss cutting, if for nothing else than to provide a little clearance and safety margin at those valve lifts. WOW, you must be extremely close to kissing off the seals as it is, and may we have discovered the reason your seals don't last too long. If you're even THINKNG of installing the 1.6:1 rockers you were talking about, you need to cut those guides and change the springs.

It's no mystery that you've popped a rocker stud. Your example is a textbook case in eveidence of the need to install screwed studs whenever changing a camshaft.

What shop are you using? They should have advised you on ALL of this as soon as they saw the heads. (Wouldn't be on 27th St., would it?)

 

Well the shop that I was using was Borchardt on 27th and no he didnt advise me of using screw in studs, which is the main reason I am very mad at him. In a mater of a few months I dropped around $4000 in his shop between the $2500 rebuild and the rest in parts I put on myself. At that time I think another $100 or so for the studs would have been well worth it, and I wouldnt have though twice about it.

Anyways now Im going to C&S in butler, they were highly recomended by my friends and so far I am very impressed with them vs. Borchardt.

(That's NOT too much cam for a 350/358. The LSA may be a little tight on a TPI, but the MAF is going to be somewhat forgiving on that.) Can you dumb that down for me a little? LSA? So is this a good cam or not? I was just looking through summit and noticed that this cam was about 2.5 times more expensive than most. ???

So do you think if I went with the springs that comp cams recomends on that cam spec I should be ok then?

Oh yeah More new info, Ive been trying to decode the chicken scratch writing on my purchase rebuild sheet from Borchardt and I noticed that he did a 3 angle valve job and put in 2.02 intake valves. It also says Port Poctets, but just looking at the heads it doesnt look like there was much if any porting done.

I think thats all I got right now, thanks for all the help and keep it coming, *** knows I need it.

Kevin

 

See? I live 100 miles away, and I know about Borchardt's. Word gets around within some circles. No flame toward them nor their services, but I've heard things...

It's very common to open up the valve bowls (pockets) when installing 2.02 valves. I'm presuming you also got 1.60 exhaust valves with that deal.

Definitely use the Comp recommended spring if you can. If not, the GMPP springs are going to be much better than the stock springs, for sure. Whatever you do, change them. The GMPP springs may be sitting on a shelf at the dealer as well, or if you're lucky you'll find good springs in a speed shop near you.

As for the cam, the total duration AND Lobe Separation Angle (LSA) determine the amount of overlap. Excessive overlap in an ECM installation can confuse the control system, but your's should be fine since you're using a MAF sensor to determine actual intake air flow.

 

Yeah, when I was looking for a place to take the motor 2 years ago a bunch of other places recomened Borchardt. It wasnt untill after I had gotten my motor back that I started to hear the horror stories from other people that had taken stuff there. The best explantion that I got was that back in the day he was one of the best, but then he got to big and had to take on more workers and then his quality went out the window, just what I heard from a few people.

I got the heads back from C&S today and yes the porting was what you said opening up the bowls. As far as the exhaust valves you would think I would have gotten those too, but no, still stock.

On my slip from borchardt it says I got "springs, seals, keepers" it doesnt say anything more about them though. I showed the guys at C&S the spec for the ones comp recomends and had them check one of mine to see if they were close. He said that he thinks they are the same as the specs and that I should be ok. Is there any way I can tell for myself ???

Oh yeah getting the GMPP stuff up here is a pain in the @ss, non of the dealerships stock anything. They said that they can order it and have it shipped up from IL in 1 to 2 days sometimes faster. But I did order the retainers and key sets that you mentioned, should be here tomorrow.

Thanks for the explanation of LSA, makes sense now.

Well I gotta get back to work now, thanks again.

 

Well, that's one of the FEW advantages of living in FIB-land, I guess. If you're ever in a real bind, Scoggin-Dickey accepts orders on their site 24/7 and ships Next Day Air if you need it. Their prices are generally very good until you get into the express shipping.

As for your springs, you're going to have to take their word for it. Unless you have access to a spring pressure test stand, all you can do is assemble the engine and check coil clearances at maximum lift. Too bad about the exhaust valves, since they tend to restrict more than the intakes. I suppose you could change them if you weren't in a big hurry, but...

 

LOL, Most people in IL dont know about the whole FIB thing.

Thanks for the tip on Scoggin-Dickey Ill keep that in mind.

Well I guess thats about it now, all I need to do is get it all back together and into the car. And see how it goes.

As far as changing the Exhaust valves and everything else I guess Im just going to wait till winter.

Thanks for all the help, Ill keep you posted on how it all goes once its back together.

 

Vader,

With the rocker studs from GMPP which ones should I get? there are 2 different styles in the catalog and the people at the dealership dont know anything I might as well be trying to order the studs from a burger king.

 

This is a case study for screw-in studs. To say nothing about the importance of getting the package right and assembly correct.

Interesting about the exhaust rotators, but it was all intakes that pulled out. Hmmm...

It's easy to for me to say when it's not my money, but why not go ahead and get the right springs installed now? Shimming up springs intended for rotators doesn't make much sense to me. And, why did you only have one spring checked? You may have gotten the one good spring out of the whole bunch. Also, was it an intake or exhaust spring they checked?

Again, easy for me to say when it's your money, but why not get those 1.6" exhaust valves now, too?

The retrofit screw-in studs would require less machining than the "normal" screw-ins. I can't tell you which p/n is which, though. "Hello, SDPC Tech Line?"

 

five7kid,

Currently I am a college student (MSOE) which is unbelivably expensive especialy with no help from the parents or anyone else for that matter. Not only is money tight but everyone other than the people that have helped me do all the work on the car are saying sell it. They obviouly dont relize how much I would lose trying to sell it in its current state after putting a whole lot of money into it not to mention the sentimental value that the car holds.

As far as the studs go, notice I mentioned that I am still new at this, learning as I go. I would have done things so very different if I had know half the things that I know now, but its to late and now I gotta work with what I got. The heads have already been machined for the studs, I just have to put them in now. As for the exhaust valves, I just plain dont have the money right now.

And Im not sure if you noticed but I did say that this was temporary so that I could actualy drive my car for a while this summer yet. And then in the winter I am going to get new heads and go all out Comp Cams everything. Well that is if I finaly get my promotion here at work. Other wise it will wait till spring. Either way next year it will be all good.

 

I've got two extra sets of studs sitting in my garage attic, the "normal", shouldered, non-guide plate kind. I've purchased two sets of World heads, unassembled w/completion kit, from two different outfits, and both times they sent me an extra set of studs (they come with the heads, and their "completion kits" also included them).

$20 for a set, shipped. Email if you're interested.

 

Well the heads are all put back together and the motor is back in the car. Now I just have to put all the stuff back on it(manifold, headers, accessories,...) Hopefuly it will be up and running by thursday.

 

Just out of curiosity, what city do you live in. Also, what are you referring to by FIB?

Ben

 

I'm interested in doing this myself with a pair of 305 heads.

I couldn't find the tech article, tho. Could anybody direct me to a thorough how-to article?

 

Anybody? Any info on tapping heads yourself?