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Just got a call from the shop working on my 350 Olds. 3711 Edlebrock is hitting lifters. (comp cams roller set up) reason for the 3711 is its a stock height manifold, and the sbo is in a shaker hooded T/A. I don't want to use the stock manifold.
I have been waiting for the heads over a year and a half (#5's) the motor has been out of this car since September. I need a solution asap.
Help please!!!!!
Last edited by bigdooly; July 13th, 2021 at 04:09 PM.
Are you sure it’s a 7111 (Perf RPM) and not a Performer? Seems to me Perf is stock height, RPM is taller.
On two different SBO Performer intake installs with roller rockers I had to grind nearly or right into the exhaust crossover for clearance, can’t remember for sure. It wasn’t a problem on those cars as the crossovers in the heads had been filled.
If it is a Performer RPM I can’t account for it. Might not have valley tray clearance but I don’t remember having issues with lifter clearance and RPMs.
Thats what I was told gotta grind, but he had a call into Edlebrock before he did that . It is a 3711 I bought it out of concern for the shaker clearance.
I am already in this thing for a good amount. Wasn't expecting this. I was considering a sniper set up.
back to the grinding my guy told me it is no a little bit I think he said about 1/2".
You had no issues with the manifold after grinding it? This is a brand new piece.
Thanks Jim
Last edited by bigdooly; July 13th, 2021 at 04:09 PM.
My bad it is the 3711 stock height manifold.
I sold the 7111 I had. The 3711 stock height manifold is interfering with lifters. I bought the stock height manifold because of the shaker.
I would rather not use the stock mandroid, I think he said the stock manifold will clear. I am at work now and I spoke on the phone with my machinist, I am not looking at it myself currently.
I don't want a taller manifold it seems drop bases are only available for Pontiac motors.
I had the same issue on the 307 in my Wife's 84 Riviera. I actually turned some of the lifters around so the link bars were up against the block and still had to do some trimming on them to keep the pushrods from hitting the rivets holding the link bars. I used the Morel street lifters I got from Chris Straub. I think I took some pictures. If I have them on my shop computer I will put them up. It was a lot of time consuming trial and error fitting work. I think I did some grinding on the intake also. And hers was just a stock cam I had Crane grind to match the original flat tappet.
Also had to cut the turkey tray to clear the lifters. Mondello had some lifters that looked to be made or trimmed to clear but the price at the time was outlandish as was the "support" I am not sure if Morel changed their design as Chris and I talked about it and I suggested that they should.
The stock manifold is actually worse if it is the same as mine
BD,
I thought I had some pics of what I did to make it work but I guess not Unless they have changed them the Comp ones will not fit with that manifold. They were my first choice.
According to Edlebrock casting is 200/1000's at minimum. We are going to attemp to clearance it.
I forgot to bring the stock manifold to the shop, so I cant say now if its better or worse but I'll take your word for it. I'll gamble with grinding this one first, if it don't work, I'll buy another manifold and deal with shaker issue. I bought it for $260 shipped new in the box from another member
on this site. I had a manifold that wouldn't seat correctly i pulled of one of the many D88's i parted, I scrapped it, boy do I wish I had it to experiment with now.
Thank you gentlemen for responding.
Curious as to why you would go thru all the trouble to use the valley pan when the ex crossovers are still open.
The whole idea of the valley pan is to keep oil from splashing on the bottom of the hot intake isnt it ? The only way I wouldn't use it would be if the crossovers were blocked. By the way my 307 is a basically stock engine in an 84 Riviera. No hot rodding at all.
So you’re worried about 180* degree oil splashing onto the intake when you have 1200* exhaust going thru it. Interesting.😣
Apparently you dont understand the reason for the shield. It has nothing to do with the temperature of the oil splashing on the manifold. It is there to keep that oil from getting baked into a carbon mess due to the heat from the exhaust crossover. That is why just about every stock engine known to man has a shield there. Anyone who has worked on stock type engines for more than a few months will tell you how bad the oil can get caked on the bottom of a stock manifold, even with a shield.
By the way, once the heat riser valve on the exhaust manifold opens there is more than likely very little actual exhaust "flow" through the manifold. I am sure it is hot but its not like exhaust is being forced through there.
In my case we are not talking about a race engine. This is a street driven engine in a 1984 Buick Riviera that my Wife drives almost daily. It might be 10 degrees outside or it might be 95 degrees. When it is 10 degrees it most likely needs the heated manifold for proper fuel atomization. That is why GM put the exhaust crossover on it
A race or high performance street engine is a totally different story. You are not that concerned with winter drive-ability so blocking the exhaust crossover is acceptable. In that case the heat shield is probably not needed but certainly cant hurt anything.
By the way, the ONLY reason the Edelbrock manifold is on the engine is there was absolutely no way the stock intake was going to work with the roller lifters. The ONLY reason for the roller can was reliability. Nothing else.
Last edited by BillK; July 15th, 2021 at 05:12 AM.
Was the cutting done to clear the roller lifters? I like the Turkey Tray but my understanding is aftermarket roller lifters hit it. I have decided to use the 330 factory replacement side gaskets as Ultraseal or similar gaskets won't fit since the heads were milled some. Yeah, roller cams are a super nice upgrade, use any oil you want with no worries.
Was the cutting done to clear the roller lifters? I like the Turkey Tray but my understanding is aftermarket roller lifters hit it.
Yes. As you can see in my other picture I turned the lifters around on the center 4 cylinders to clear the intake so they didnt hit the turkey tray either. Thats why I only cut out the ends. If this was a performance build with the heat crossover blocked i would have done away with the turkey tray also.
Bill I understand everything. But if your biggest concern is oil coking on the bottom of the intake you’re missing the point.
Have a nice day. Continue gentlemen.
Bill I understand everything. But if your biggest concern is oil coking on the bottom of the intake you’re missing the point.
Have a nice day. Continue gentlemen.
Ok then I guess I am stupid. What exactly is your point ????????
Yes. As you can see in my other picture I turned the lifters around on the center 4 cylinders to clear the intake so they didnt hit the turkey tray either. Thats why I only cut out the ends. If this was a performance build with the heat crossover blocked i would have done away with the turkey tray also.
I not filling my heads, running the Performer because I don't want it on the shelf forever, saving my RPM for future endeavors and plan on running the hot air choke. Oil cooking on is the least of my worries and we have a lot of cool weather in the spring and fall. Once broke in, I will probably run our Dexos approved 5W30 truck grade full synthetic, that will minimize the oil coking issue.
[QUOTE=olds 307 and 403;1356159...full synthetic...will minimize the oil coking issue.[/QUOTE]
Good solution.
Another solution: On a car driven in winter, I had the center two exhaust passages in the heads filled with molten aluminum, I ported the bowls for those exhaust passages, and had the machinist drill a 1/2" hole through the aluminum to one of the exhausts to allow sufficient heat for the manifold. There was no coking on dino oil. And it ran well in -20 °F weather.
Bill-looks like your skeeeeered of those flat tappet cams............
I just did not want to take a chance but if I had realized how much trouble going to a roller was going to be when I started I would never have done it. The original flat tappet cam from 1984 lasted 250K miles and was still in good shape. I personally have never had a problem with a flat tappet cam but I have not built an engine with one in quite a while. That and hearing all of the problem guys have with them I figured the roller was an easy way to go.
I was always told that using the turkey tray pan gasket was a no no with an aluminum intake. 100% chance of failure with dissimilar metals and to use a nice thick two piece. But that was Joe Mondello back in the 90's, I'm sure its different now?
I was always told that using the turkey tray pan gasket was a no no with an aluminum intake. 100% chance of failure with dissimilar metals and to use a nice thick two piece. But that was Joe Mondello back in the 90's, I'm sure its different now?
The factory intakes do spring leaks from time to time, usually after many years and miles. We only saw a few fail in a shop setting, I think they were actually iron intakes. Most of the cars that came in were iron intakes in big cars with 5A head 307 motors. I had at least 5 apart, sometimes with quite a few years in between with factory and aftermarket aluminum intake all using the Turkey tray and stainless side gaskets with no amount of galvanic corrosion present.
I was always told that using the turkey tray pan gasket was a no no with an aluminum intake. 100% chance of failure with dissimilar metals and to use a nice thick two piece. But that was Joe Mondello back in the 90's, I'm sure its different now?
The factory did it with the W intake manifolds and the later GBody intakes. As long as the coolant is properly maintained there shouldn't be an issue.
Ok then I guess I am stupid. What exactly is your point ????????
I never said you were stupid, and I don’t think you are stupid.
But I believe you’re not thinking clearly here. What cokes the oil to the intake, the temp of the oil or the temp of the exhaust going thru it?
The latter. Hot oil won’t coke like that, it better not or the entire inside of the engine would look the same.
There’s no “shut off” for the exhaust flow thru the intake. In other words yes you can shut the heat riser off but the exhaust will still transfer heat into that part of the intake, flow or not. The center two ex ports in the heads are open to the intake 24/7 are they not?
Hope this helps.
Eric,
Of course i understand that it is the exhaust heat that cokes the oil. That is the reason for the valley pan on stock engines. I guess I just didnt get what point you were trying to make especially since my engine is basically stock in a daily driver. Unless you were referring to the original poster engine in which case this entire conversation didn't happen
The factory did it with the W intake manifolds and the later GBody intakes. As long as the coolant is properly maintained there shouldn't be an issue.
I get it, I'm just saying I aske Joe the question in person and he said the aluminum and iron expanding and contracting at different rates was an issue and he recommended a thick two piece gasket. He also recommended dimpling the china rails with an awl before using a silicone bead on it, and tossing the end seals in the trash. That seems common place these days too.
Location: Colorado Springs Colorado/Thousand Oaks Ca
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Originally Posted by BillK
I just did not want to take a chance but if I had realized how much trouble going to a roller was going to be when I started I would never have done it. The original flat tappet cam from 1984 lasted 250K miles and was still in good shape. I personally have never had a problem with a flat tappet cam but I have not built an engine with one in quite a while. That and hearing all of the problem guys have with them I figured the roller was an easy way to go.
Yaaaa that makes sense, Bill you should try my Guy Spirro on your next FT cam, no problems!
July 13th, 2021, 03:11 PM
I am not sure if Morel changed their design as Chris and I talked about it and I suggested that they should.
