XE258 cam ??

[1QWKVERT]

just because comp says its a good replacement doesnt mean that it will work with your motor...make sure you check your piston to valve clearance after you put in the cam.....

Just stop....

 

[zoomie]

i dont doubt one bit, i already planned on checking p/v with clay, i also am already looking at checking out flycutting and perhaps better pistons
once i build this motor i want it to last a very long time. so im going to take my time and do it right the first time, im really glad there are many ppl alot more knowldageable about things than me that means i learn soemthing new everyday! i always welcome new stuff to learn
here are the things ive learned over the past few yrs
1.) i know alot about nothing
2.) i know enough to be dangerous
3.)when in doubt ask alot of ??????s-this has saved my butt more than once.
4.)if still not sure refer to rule no3

even though i consider myslef a panther tech, there is still much that i do not know what i do know i share gladley if someone asks. however i am forever learning and greatly appreciate those that take the time to share with me knowledge that hopefully i may one day impart to someone who asks me the same noob ??s i ask lol. founda guy on a bronco forum that runs this cam im asking him what he did to make it work.

 

[97modgt]

Just stop....

lol. Some people just say be carefull when changing out components. It never hurts to double check. It like this. Physics say helicopters won't fly but I am sure you have seen one in the sky.

 

[1QWKVERT]

Physics say helicopters won't fly but I am sure you have seen one in the sky.

Who says that!?!? :smash: lol

 

[TERROR]

Just stop....

im not even going to respond........ make sure you post up some pics of your pistons after they kiss the valves a few times..

 

[stanginthe11s]

zoomie, I will give you 2 pieces of advice that 20 years of racing has taught me.
1) If you plan on building it right once then dont waste time or money on a cam right now, that will be one of the last things youll get and plans change over time so you never know what parts you may decide to use in the end.
2) If the setup you are thinking of consists basically of gt 40 heads and intake you may want to use a stock 90 cam with 1.7 rockers. the stock cam will carry you into the 11's n/a with no problem and the gains if any from an off the shelf cam will be small.

 

[zoomie]

zoomie, I will give you 2 pieces of advice that 20 years of racing has taught me.
1) If you plan on building it right once then dont waste time or money on a cam right now, that will be one of the last things youll get and plans change over time so you never know what parts you may decide to use in the end.
2) If the setup you are thinking of consists basically of gt 40 heads and intake you may want to use a stock 90 cam with 1.7 rockers. the stock cam will carry you into the 11's n/a with no problem and the gains if any from an off the shelf cam will be small.

well the basic setup is a modded HO conversion ,i do have a stock gt cam from a 95 right now and 19 lbrs just need to get a few othr parts waiting on tax money right now lol
the cam that i picked out was actually a suggestion from a guy i know who autoX his wagon hes running a XE264, but just to be safe im going to get a exploder motor to do the main buildup on.
basically from what i read almost evry component i have picked out is designed for tourqe, mainly the cam and the afr165 heads that i want to get
seemes like a nice combo fo my heavy car. only reason i want the cam right now is that i can pick up a new one for 180 shipped.im not so sure a stock stang cam and a gt40 heads and intake will take my car into 11's i have a pretty heavy car 4000lbs + low 15 highs i know for sure becuase i know ppl who have done that lol .im building 1 piece at a time for right now.

 

[EHA Racing]

OK, so lets start with the cam, its pretty simple. if lets say i have a cam with .3 lift and I decide i want a cam with say .9 lift and nothing else but the lift has changed then there is absolutely a chance that there will be no interference. it doesn't matter if the pistons are full flat top which was only used in 86 or if they have reliefs, you absolutely cannot give cam advice based on lift alone as lift while playing a part doesn't play a big enough part in itself to dictate p/v issues. A cam can be advanced or retarded 2* to change p/v clearance, a cam can be ground differently, the duration is a big player in cam fitment and selection and the total spec package is what is used to determine fitment issues.
As for pistons, just about every 289,302 and 351w has some kind of relief in the piston from the factory(86 year being the exception) be it 2 reliefs, 4 reliefs , reliefs with a dish or just a dish. We dont know what he has as theres always the exception to the rule but its more likely there are reliefs in his motor and if by chance there aren't, even in 86 we put cams in our motors so long as we watched the duration #'s there were no issues. When choosing any parts for a motor you cant look at the part as an individual, you have to have a working knowledge of the motor and how each part will work together with the rest of the platform, also knowing how different manufacturers rate or spec their product helps. one point to that is most companies base off of zero deck, I have yet to come across a stock motor that has zero deck and in fact its been more common to be .020-.030 in the hole which of course just adds more clearance for p/v. If thats the cam you want, buy it, when you are ready to upgrade your parts then you'll know. comp cams will take a cam back if its unopened years after you purchased it so you have time. If you cant wait then just look down a spark plug hole for reliefs.

Great advice! When I get some time I will be putting up some info about SBF engine assembly and how to check PV clearance (ther right way).

 

[EHA Racing]

Zoomie, when you get all the stuff for your engine and have a little cash I would recommend you come up to my shop and we can degree the cam and check you PV clearance (not with clay). You can hang around and I will show you the right way to do it and what to look for. Also, you have to make sure that the springs you are using are the right ones for that cam. I can also measure up the pushrods you will need as they are not one size fits all. I'm only 45 minutes from Jamestown.

 

[zoomie]

Zoomie, when you get all the stuff for your engine and have a little cash I would recommend you come up to my shop and we can degree the cam and check you PV clearance (not with clay). You can hang around and I will show you the right way to do it and what to look for. Also, you have to make sure that the springs you are using are the right ones for that cam. I can also measure up the pushrods you will need as they are not one size fits all. I'm only 45 minutes from Jamestown.

zounds good mang! it might be alittle bit. id love to hangout and learn stuff more i learn better mech that makes me lol. i know about the springs and stuff comp has a spring set pt# 986-16 and rods 7826-16 however if i can find a spring set and rods( i know ill need hardend rods) that are comparable but not so pricey id like to find some.

 

[sbeachstang]

zoomie, I will give you 2 pieces of advice that 20 years of racing has taught me.
1) If you plan on building it right once then dont waste time or money on a cam right now, that will be one of the last things youll get and plans change over time so you never know what parts you may decide to use in the end.
2) If the setup you are thinking of consists basically of gt 40 heads and intake you may want to use a stock 90 cam with 1.7 rockers. the stock cam will carry you into the 11's n/a with no problem and the gains if any from an off the shelf cam will be small.

This is great advice, and I completely agree. And yes, cam lift has very little to to with P/V clearance, Lobe seperation and over all cam timing events dictate P/V clearance, which should always be checked.

 

[zoomie]

zoomie, I will give you 2 pieces of advice that 20 years of racing has taught me.
1) If you plan on building it right once then dont waste time or money on a cam right now, that will be one of the last things youll get and plans change over time so you never know what parts you may decide to use in the end.
2) If the setup you are thinking of consists basically of gt 40 heads and intake you may want to use a stock 90 cam with 1.7 rockers. the stock cam will carry you into the 11's n/a with no problem and the gains if any from an off the shelf cam will be small.

just reading through and didnt catch this the first time

I value your advice, however my car is a 4000 lb brick, even with a 1.7s and an HO conversion im looking at low 15s, however i did manag to find a HO motor from a mark vii to use, so now i will be building an engine using that, now i have to figure out how to make it 9:5:1 compression. i have thought about having the heads milled and also slighty ported, along with the lower intake ported and port matched. btw i would love to make this a 11 sec sleeper!!! but i want it to be n/a

 

[V8Demon]

Not worth it IMHO......Especially in a heavy car. Especially in one with an AOD -- Not with stock heads.....


The differences between the non-HO and HO motors go deeper than the pistons and cam.....

The standard output (non-HO) passenger car fuel injected 5.0 was installed in the following cars:

1986-1988 Thunderbird/Cougar
1986-1991 Crown Vic/Grand Marq/Town Car/Continental
1986 Mark VII (non LSC versions)

These engines had the following:
--E6 casting heads with 68 cc chambers and smaller valves than their E7 counterparts.
--A MUCH smaller cam designed for low end grunt/low RPM cruising. This cam has the old school 302 firing order. 1-5-4 ......
--Pistons with a 2.5 cc dish and no valve relief (the overwhelming majority are cast -- there are reports of the very early style of this piston coming forged. They were available forged through aftermarket. HO pistons have the same dish AND valve reliefs that add up to another 4 cc for a total of -6.5 cc as opposed to -2.5...... The non-HO pistons also use different rings.
--Different upper intake manifold & throttle body. Stock HO manifold has a 60 mm opening for 87-93 (58mm in 86) as opposed to the 50 mm opening on the non-HO cars. Lower intake is the same. More evidence that on a stock HO motor the lower intake is the bottleneck.....
--14 pound injectors. Yes 14. It's been proven that 8 of these injectors WILL support just a hair over 200 HP on an N/A motor, but they're pushed to the max.....

**The base 5.0 cars came with smaller fuel pumps as well as different ECU's tailored for their smaller injectors/cam.
**The rods and crank are identical between the non-HO and HO cars.
**All the non-HO 5.0 passenger cars were speed density EXCEPT the CV/GM/TC in model year 1991 only. These are the only cars with a base model passenger car 5.0 AND mass Air
**Every Mark Vii ever made with a fuel injected 5.0 left the factory with speed density -- both HO and non-HO



The Mark VII was HO in all 87-92 models. Prior to 87 they came with the base motor with the HO as an option. It was part of the LSC package. The only years for the 5.0 HO in Cougars and T-birds were '91-'93. No V8 in either in 89-90 (still hadn't designed that low rise intake minifold yet -- the optional motor was the supercharged 3.8)and all prior years were base model 5.0s. Interestingly enough the 93 Cougar and t-bird 5.0 has the same cam as a '93 Cobra, but with stamped 1.6 rocker arms as opposed to the 1.7 ratio roller rockers the Cobra had. If you find one of these motors, a stock 85-93 HO cam is actually an upgrade. 91-92 Cougars/T-birds had the HO cam.

The Explorer 5.0 was in Explorers and Mountaineers from '96-2000. 96 had GT-40 heads (the normal ones -- not the "P").The P heads were introduced halfway through the '97 model year. The issue with the P heads is the spark plug location and how it can interfere with exhaust header tubing. the HO cam is an upgrade over the Explorer cam as well. An Explorer/Mountaineer motor really wakes up with the HO cam and some 1.7 raio rockers.

There is also the F-150. E7 heads and 19 pound injectors BUT tiny flat tappet cam and the old school 302 firing order (non-HO) until '94, which was the first year for Mass Air in an F-150. All previous years were Batch fire Speed density -- not even SEFI Speed Density like the cars.


As far as whether or not a certain cam will work with X heads and Y pistons:

PISTON TO VALVE CLEARANCE CHECK PROCEDURES:

Piston to valve clearance is the relationship is just that, the distance from the valve to the piston during the most critical time in the engines cycle, that time is the "overlap". No other time during the engines cycle is the piston closer to the valve than in the overlap. Overlap occurs at the end of the exhaust stroke and the beginning of the intake stroke. This is the time when both the intake and the exhaust valves are open simultaneously.

A lot of people have used the max lift number when calculating piston to valve clearance and that is probably the single worst method. When the valve reaches it's maximum lift point the the piston is actually furthest away traveling down the cylinder bore drawing the intake charge in. The minimum clearances commonly used are .080 on the intake valve and .100 on the exhaust valve. For people using an aluminum rod it's a good idea to allow more clearance as the aluminum rods stretch when in operation.

To use the clay method take a 1/4th inch amount, cover the valve reliefs on your piston and rotate the engine one full cycle. Make sure it's 2 revolutions past top dead center. Take the head back off and peel the clay away. The best benefit of clay is that you can use an x-acto knife and cut it into sections and measure exactly where the thinnest area is, if there is any. Remember .080 and .100 minimum thickness.

The next method takes a little practice but is great if you don't want to take the heads off the car, although it will be necessary to replace the intake and exhaust valve springs on one of the cylinders. It's best to use a checking spring, but if you don't have a dedicated light weight spring, take a trip to your local hardware store. Remember the spring only has to have enough pressure to keep the valves fully closed and return an open valve back to it's closed position.

Now you want to adjust the rockers to zero lash. What is important here is if you are using a hydraulic type cam, whether it be a hydraulic roller or flat tappet hydraulic cam. Do NOT preload the lifter. All you want to do is take all the movement out of the pushrod WITHOUT collapsing the plunger in the lifter. Make sure you do this adjustment when the lifter is on the base circle of the cam which is at top dead center on the compression stroke.

You will need feeler gauges set to 0.100 thousandth's. Start with your piston at top dead center and rotate one full revolution in normal operating rotation. The piston starts traveling back up the bore, the exhaust stroke starts to occur, and the exhaust valve will start opening. Watching the valve train you will notice the exhaust valve opening till it's fully open. As you are approaching top dead center you will notice the intake valve starting to open before the exhaust valve is fully closed. This is the area of overlap, usually about 10-15 degrees before and after top dead center. Both the intake and exhaust valves are open and the piston is near the top. During this overlap point is when you want to measure the piston to valve clearance.

The piston is so close to to the top that you can push down on the nose of the rocker and actually feel the valve making contact with the piston. Now; with your feeler gauge set to 0.100, insert the feeler gauge between the valve stem tip and the rocker arm. If you can insert the gauge at 0.80 for the intake and 0.100 for the exhaust then you have enough piston to valve clearance.

It may take you some trial and error before you can identify the precise overlap period at which you need to check the clearances, but this is a good way for someone that does not want to take off the heads.

I highly suggest you go through the steps above several times, it is VERY easy to miss the overlap, resulting in very inaccurate measurements. Work slow and this process can be accomplished by just about anyone.

Final note, if your measurements are say less than 0.10, for example there is .090 clearance on the intake you can retard the camshaft and play around with that but remember that will also affect performance characteristics of the cam.

Hope this helps

 

[zoomie]

excellent info on the PTV clearence, however the rest i already knew, spent the last 3 yrs doing my research. i will be using gt40 heads, and intake,as well as beehive springs, and hardened pushrods. IMO stock HO conversion will take a linc in the low 15s. idid happen to find out there are 2 part numbers for the XE258 one is 35-512-8 and the other is the 35-510-8, which is the one that i will be using. also will have 3.55 tracloc. limo springs, and police shocks all the way around. i will also probably be running 60 series tires as well. so milling the deck for compression, not much mind you all i want is 9:5:1 i know its not a preffered ration,however it should allow me to use pump gas as low as 89.. i think. oh and i will be using 1.6 roler rockers as well, and quite possiably a gear drive timing set.


zoomie@grandmarq.net