Blacktop Posted March 30, 2020 Author Share Posted March 30, 2020 See that's what confuses me. On paper that cam is no better than the factory ones other than the basic operating range shifts a little which isn't enough to really be noticeable. The LSA is a little tighter for overlap for the shift in operating range but nothing major. The XE250H is nothing like the 1980 - 1986 stock emissions-style cam in trucks with the 5.0 or 5.8 (2V). It is a better cam that what came in the first generation (1993 - 1995) F150 Lightning. It is very much like the cam found in the 1984 - 1987 truck 5.8L H.O.(4V) or the legendary Mustang 5.0L H.O., with more of an emphasis on low-end torque rather than high RPM horsepower. Thanks all for your opinions and all the info:nabble_anim_claps: That is just the help I was needing. The engine did used to have all the emissions and computer controlled 2 barrel carb so its safe to assume it also has the emission restricted cam in it too. I'm sure the 250 cam will increase low down torque over the emission stock cam which is exactly what I'm looking for. I will probably fit my spare edelbrock heads instead of using the stock emission heads if they have the restrictions in the exhaust ports. Once again, thank you for the info. Alan Link to comment Share on other sites More sharing options...
Gary Lewis Posted March 30, 2020 Share Posted March 30, 2020 Thanks all for your opinions and all the info:nabble_anim_claps: That is just the help I was needing. The engine did used to have all the emissions and computer controlled 2 barrel carb so its safe to assume it also has the emission restricted cam in it too. I'm sure the 250 cam will increase low down torque over the emission stock cam which is exactly what I'm looking for. I will probably fit my spare edelbrock heads instead of using the stock emission heads if they have the restrictions in the exhaust ports. Once again, thank you for the info. Alan You can bet the heads have the humps in them. They may be D8OE's, and those are about the worst that Ford made. Huge humps. Go with the Eddys. Link to comment Share on other sites More sharing options...
Jacob84 Posted March 30, 2020 Share Posted March 30, 2020 Currently considering the XE250H from Comp Cams I did some looking at that cam and it's comparable to the 351w HO cam. The biggest difference I saw was the LSA difference. The 250 cam has a tight LSA but they make up for that by advancing the intake valve timing considerably. There is also a little more lift with the HO cam and more exhaust duration. The 351W HO cam with lifters is also cheaper than the 250 cam with lifters if that's a concern. I know you're looking for torque though. One thing I noticed on the dyno sheet provided with the 250 cam was that it made peak torque at 3,700 rpm and peak HP at 4,600 (with a mild 350). The HO cam makes peak torque at 2,800 and peak HP at 4k. Although, the 250 cam makes REALLY good torque throughout the entire rpm range. I'm definitely not trying to talk the 250 cam down, it seems really good, but just a difference I thought you might want to know. Might be something to think about since you'll be running 35s which aren't light. I don't think you'll be disappointed with the 250 cam. It's proven and people have had good experiences with them. If your heart is set on it, go for it, I'd like to know how it works out for you especially with a relatively stock motor. I can get a little carried away with making torque out of a stock 351w, one of my favorite things to talk about. There is one upgrade I would consider when you rebuild your motor. If you have D8 heads (I did on my 84) I would highly recommend you find some E7 heads from a later model 351w. Those D8 heads are terrible. They are the worst heads Ford ever made (very restrictive even for a stock head). Now the E7s aren't a massive upgrade but they do flow better on the exhaust side and have slightly more compression which will help you build some more torque. The only thing I would use D8 heads for is a boat anchor or an oversized paper weight. Link to comment Share on other sites More sharing options...
Blacktop Posted March 30, 2020 Author Share Posted March 30, 2020 The 250H is basically what one would consider an old school RV cam, kinda. For what you are doing I think you'll be happy with it, just don't expect it to scream to 6k rpm. Here is some information for you, with some things to consider. This might open some eyes. My father has a Napa KC1158R in his truck. That cam is a STUMP PULLER. The XE250H is has slightly better lift and duration. However, lets evaluate. By comparison, here are the advertised specs that matter. Comp Cam XE250H: Duration @ .050": 206/212 Lift: .432/.444 LSA: 110 Napa KC1158R (302 Firing Order): Duration @ .050": 194/204 Lift: .424/.448 LSA: 110 This is entirely assuming the rest of the engine is fairly stock. By comparison, the Napa cam has slightly less overall duration than Comp Cam. This leads to believe it will build torque a little lower in the RPM's (we are talking maybe 200rpm difference) and the Comp cam will rev a hair higher. I would expect torque values as a whole say on a dyno are probably about the same between the two but shifted in different spots in the RPM range. The issue with our engines is the exhaust side of things has always been hampered from the factory. The Napa cam has slightly better exhaust lift and a weaker intake side, almost intentionally. This is a good thing especially when mated which larger valving in the heads. Personally, he's running 2.02/1.54 valving I believe, maybe 1.60 I can't remember. Here is the head scratcher. Neither one of these cams are anything particularly better than certain year FACTORY camshafts and are merely meant to be STOCK replacements. In fact, both are actually WORSE (depending on what you are doing). These cams above and the stock cames make similar power except they shift that usual power down in the RPM range a little. By comparison, lets take a look at some factory specs. Standard 351W Duration @ .050": 206/221 Lift: .445/.453 LSA: 112 HO 351W Duration @ .050": 210/221 Lift: .453/.453 LSA: 112 Factory F4TE Roller Cam Duration @ .050": 256/266 Lift: .422/.448 LSA: 116 That factory roller cam isn't really worth converting over to in my opinion. The specs look better overall, but roller cam specs are far different than flat tappet cams and cannot be measured the same due to the style lifter. In my opinion as a whole overall, the biggest change you can make that would produce a noticeable difference is converting to 1.7 rockers to increase overall lift (as long as your pistons clear you will need to do a little digging) and running a Comp Cams 260H grind. It will still give you the nice smooth idle like stock and pull great vacuum (I think around 17") for power brakes, but you will blow the doors off any other cam listed here. The 260H is right about what a stock 351 HO has factory. Upgrading the rockers will allow you to gain a substantial amount of lift while retaining stock driveability characteristics. Odds are you have the standard 351 cam, so this would be an exponential improvement. Comp Cams 260H: Duration @ .050": 212/212 Lift with stock rockers: .447/.447 Lift with 1.7 rockers: .474/.474 LSA: 110 I think you would be extremely happy with an 260H over the rest of these especially if you spend the money on a rocker upgrade. It's apart. Now is the time to do it. I also have a spare set of scorpion 1.72 roller rockers. They were going to be used on my next 5.0 roller build but I could see them ending up on the 351 instead. Link to comment Share on other sites More sharing options...
Blacktop Posted March 30, 2020 Author Share Posted March 30, 2020 Currently considering the XE250H from Comp Cams I did some looking at that cam and it's comparable to the 351w HO cam. The biggest difference I saw was the LSA difference. The 250 cam has a tight LSA but they make up for that by advancing the intake valve timing considerably. There is also a little more lift with the HO cam and more exhaust duration. The 351W HO cam with lifters is also cheaper than the 250 cam with lifters if that's a concern. I know you're looking for torque though. One thing I noticed on the dyno sheet provided with the 250 cam was that it made peak torque at 3,700 rpm and peak HP at 4,600 (with a mild 350). The HO cam makes peak torque at 2,800 and peak HP at 4k. Although, the 250 cam makes REALLY good torque throughout the entire rpm range. I'm definitely not trying to talk the 250 cam down, it seems really good, but just a difference I thought you might want to know. Might be something to think about since you'll be running 35s which aren't light. I don't think you'll be disappointed with the 250 cam. It's proven and people have had good experiences with them. If your heart is set on it, go for it, I'd like to know how it works out for you especially with a relatively stock motor. I can get a little carried away with making torque out of a stock 351w, one of my favorite things to talk about. There is one upgrade I would consider when you rebuild your motor. If you have D8 heads (I did on my 84) I would highly recommend you find some E7 heads from a later model 351w. Those D8 heads are terrible. They are the worst heads Ford ever made (very restrictive even for a stock head). Now the E7s aren't a massive upgrade but they do flow better on the exhaust side and have slightly more compression which will help you build some more torque. The only thing I would use D8 heads for is a boat anchor or an oversized paper weight. OK, that's my mind made up then. The stock heads wont be reused. I'll go with the edelbrocks:nabble_smiley_good: It'll have an air gap intake and a holley 600 vac sec too as well as duraspark hei ignition. Thanks again guys, Alan Link to comment Share on other sites More sharing options...
LARIAT 85 Posted March 30, 2020 Share Posted March 30, 2020 OK, that's my mind made up then. The stock heads wont be reused. I'll go with the edelbrocks:nabble_smiley_good: It'll have an air gap intake and a holley 600 vac sec too as well as duraspark hei ignition. Thanks again guys, Alan If your truck is a daily driver or one that will be driven in colder temperatures, I would *not* recommend using the Air Gap intake. Link to comment Share on other sites More sharing options...
Angelo Voltura Posted March 30, 2020 Share Posted March 30, 2020 See that's what confuses me. On paper that cam is no better than the factory ones other than the basic operating range shifts a little which isn't enough to really be noticeable. The LSA is a little tighter for overlap for the shift in operating range but nothing major. The XE250H is nothing like the 1980 - 1986 stock emissions-style cam in trucks with the 5.0 or 5.8 (2V). It is a better cam that what came in the first generation (1993 - 1995) F150 Lightning. It is very much like the cam found in the 1984 - 1987 truck 5.8L H.O.(4V) or the legendary Mustang 5.0L H.O., with more of an emphasis on low-end torque rather than high RPM horsepower. According to paper they are almost identical. Link to comment Share on other sites More sharing options...
Blacktop Posted March 30, 2020 Author Share Posted March 30, 2020 OK, that's my mind made up then. The stock heads wont be reused. I'll go with the edelbrocks:nabble_smiley_good: It'll have an air gap intake and a holley 600 vac sec too as well as duraspark hei ignition. Thanks again guys, Alan If your truck is a daily driver or one that will be driven in colder temperatures, I would *not* recommend using the Air Gap intake. Its not a daily, its a weekend toy. Also, just remembered I have a pair of stock heads with new valves. Had a look at the casting numbers and they are 1969 302 C9OE's. They have a small hump in the exhaust ports that I can easily remove so they might be an option too:nabble_smiley_good: Link to comment Share on other sites More sharing options...
Gary Lewis Posted March 30, 2020 Share Posted March 30, 2020 Its not a daily, its a weekend toy. Also, just remembered I have a pair of stock heads with new valves. Had a look at the casting numbers and they are 1969 302 C9OE's. They have a small hump in the exhaust ports that I can easily remove so they might be an option too:nabble_smiley_good: Best check the volume of those heads or you might have a bit too much compression ratio. Link to comment Share on other sites More sharing options...
LARIAT 85 Posted March 30, 2020 Share Posted March 30, 2020 I did some looking at that cam and it's comparable to the 351w HO cam. The biggest difference I saw was the LSA difference. The 250 cam has a tight LSA but they make up for that by advancing the intake valve timing considerably. There is also a little more lift with the HO cam and more exhaust duration. The 351W HO cam with lifters is also cheaper than the 250 cam with lifters if that's a concern. According to the specs I have, it looks like the XE250H cam has more lift than the 5.8L H.O. cam, but less exhaust duration: Ford 5.8L H.O. cam: .206 intake, .221 exhaust @ .050 .440 intake valve lift, .450 exhaust valve lift 115 degrees lobe separation Comp XE250H cam: .206 intake, .212 exhaust @ .050 .460 intake valve lift, .474 exhaust valve lift 110 degrees lobe separation Ford 5.0L H.O. cam: .210 intake, .210 exhaust @ .050 .444 intake valve lift, .444 exhaust valve lift 115 degrees lobe separation Link to comment Share on other sites More sharing options...
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