When using the jets to restrict flow to the heads how many jets are needed?

 

Do you have a high volume pump? If so just swap in a standard volume and the problem will be solved! Bigger is not always better! you should only need 2 one for either head. FE's are notorious for having to much oil in the heads aka valve area.... check the the galleys that drain your heads, make sure they are clear the opening is about 7/16 of an inch..... It is common that they are plugged with RTV after installing the heads to the block. RTV will ooze into the galleys. You must clear these galleys or even installing the flow restricting jets will not stop them from over filling, causing starvation back at the oil pump due to the oil not getting back rapidly enough to the pan. If you have a high volume pump, you have only made the matter worse... Also the valve train bolts go in, in a specific order, as one is a shouldered bolt to allow oil passage to the rockers, if installed in the wrong locations this will cause rocker arm starvation and failure.... Good luck with it

 

Thanks jet, the motor has less then 30k miles and does have a high volume melling pump. I drive for extended periods of time above 3k rpm and it blows oil out of the driver side breather on the valve cover but only when I get on the throttle at that high rpm witch leads me to believe they didn't restrict the heads. Also I've read about 5 different articles on oiling mods and the jet sizes have ranged from #69-#90?

 

My first thought for you if you are getting oil blowing out the breather on acceleration.... what is your compression? sounds like you might have bad rings...Blowby is more likely to cause that problem, that would be a lot more likely to blow oil out the breather. But if your compression is good, why pull the engine apart to add in the jets when you can drop the pan, and in about 10-15 minutes put in a standard volume melling oil pump which should be in there anyway, then your oil problem will be solved without having to drill out and tap oil galleys, which means basically an overhaul. Putting restrictions on the oil flow just adds stress to the oil pump, making it work harder causing loss of Horsepower... swapping to a stock oil pump will require less horsepower to turn, so it is a win win . By adding the Jets in your are just curing a symptom, but by putting the proper oil pump in your solving the problem Think about that! your truck is not a circle track racer, or an indy car, or regular bracket racer... it is however a daily driver, and you have to build your engine accordingly.... again Bigger is not always better!

 

Ok well again my engine is not stock and around 400hp 10:1 compression and a mid level cam so I need a the better pump plus I drive it long distances at somewhat high rpm. My understanding was that you don't need to drill and tap anything to put the jets under the rocker shafts and if that's all I have to do and not worry about if I'm pumping enough oil then great. I also have no drop in power or smoke from the exhaust or oil burning so I don't think its the rings.

 

My engine is 438 hp and spends all day on Southern California freeways,,, I still use a stock Melling pump, and never have an oil feed issue, Mine is a 352 with roller cam, and roller rockers, a Comp Cam 264 cut.. with headers, high flow GT heads, edelbrock 390 intakes with an edelbrock 1805 650fm Carb... so what is your point...? a high volume pump is still a bad idea... it draws the oil out of the pan faster than it can return to the pan and as I said you are not racing your truck at 5-6 grand for 3 hours at a time so you have no reason to use the high volume pump... I don't know why you are not getting this? Do you know how the oil gets into the heads? it doesn't seem that you do? the oil travels up a galley around one of the rocker system bolts, the bolt is a shouldered bolt, where you are going to put an orifice I don't know because it would have to go around that bolt, which would cut off the oil supply. So you are going to mess with experimenting with your valve train when all you have to do is change oil pumps... Dude Seriously? it is your choice, but it would be a stupid choice... a Stock Oil pump will handle anything you can throw at it... this is not a chevy that needs extra oiling! But do what you will...he he I will be laughing!

 

Seriously? Lol why is this mod so highly recommend for Fe motors then? And why do aftermarket heads come pre restricted? Also the jets go under the rocker arm shaft as far as what I've read about it, seems more cost effective for $6 jets then a new pump, oil pan gasket and 6 quarts of oil. But again I'm just going off of what I've read on many many forums and articles including here. So laugh all you want.

 

hey I am not the one with the oil feed problem I read about the pros and cons, and I chatted with several FE builders that do this for a living all of them said it was a waste of time, but do what you want I really don't care... ! cheers!

 

No worries, you did come off kind of dickish though, I'd rather have to do this then worry about getting enough oil to where its got to go 150 miles from home in the middle of the desert lol. Thanks for your input though.

 

Crawler, I'm no engine builder but I ride behind one everywhere I go.

My FE engine does have jets in it, and it seems like mid 70s size. The first thing in my mind is why is this guy driving that many miles turning those rpms. You gearing must be 4.11 or 4.56 to create that. You ought to have a tire burner for sure with that ratio and drinking gas by the bucket.

I also think the high rpms is making excessive internal pressure causing the oil to escape. My 06 F150 with 106,000 miles is as dry as a bone, I can wash my FE take it out for a run and there is weeping already started. I was in a shop earlier this week talking to the guy there about newer engines having less pressure in the block and the engine bay being clean. The guys back then had pride in their milling, the fits had to be good. It has to be the design is better.

I will agree with jet that the standard pump should do the job. You may want to look at getting your rpms down for the hi-way, or work a lot of overtime.

just a thought




John

 

Yeah I'm running 456 gears with a 35in tire and will be moving up to 38in soon. The motor can take the rpm for an extended period of time and I mpg isn't that bad at 10mpg loaded to go to the desert and up hill most of that time, only problem is oil out the breather. The po said the engine was built by a marine engine builder so it can run at high rpm for a long time because the truck was used for offroad recovery when his brother who had the buisness couldn't get someone out. I just want to fix the oil problem without spending a bunch of cash. I'll try the jets and if that doesn't work then well we'll see.

 

That's what everybody told me too. They said unless I was turning more than 5,000 rpm for an extended amount of time it might be worthwhile.

 

I do see over 5k quite often but not for long periods, thanks for everyones help.

 

Dang in the 12 or so years that I have had my current slick, I think about 4500 is as fast as I have turned it, and that was in second gear.

With the 3.25 gearing 3,000 rpms has the speedo needle standing pretty tall. Don't know if it would achieve 5000 rpms in high gear.



John

 

Before I tore my stock 352 out I figured I would just see if it would hit 5,000. It started to miss slightly at about 4,800 in 3rd. It ran smooth though.