I am getting a machine shop to fix up a '96 351w out of a F250. This is going into an estimated 4,000-4,500 Lbs mud/trail truck. I am new when it comes to engine building and looking for a little help from the masses. Knowing nothing and just doing research on the internet, I am thinking I want a Holley Truck Avenger 670 carb, an Edelbrock Performer RPM Intake, AFR 185 Renegade heads, Extreme Energy 224/232 Cam from CompCam, the cylinders are already bored to 30 over. Reusing the stock/OEM crank shaft so no stroker for this motor. Running Hedman 88400 headers. I have 5.38 gears spinning 38.5" tires(Will go bigger when these tires wear out.) This is meant to play in the mud but want to do grocery runs occasionally or go pick up the kids.

The machine shop I am working with is telling me that they have a pair of AFR195 heads that will work well for my application and will make good power down low, where I want it, with the correct cam being used. Then saying to use a 750 CFM Carburetor. I just don't want to get a motor built that is built to run 3,000 to 7,000 RPM but I have a cam only running up to 6,000. With this set up will I still have the low end torque I desire? Don't want a dog off the line that right when it is getting to the meat of the power, the cam is done and it falls on it's face.

Are these changes negligible in the grand scheme of things?(What I have been told and want to believe)

Thanks for any and all input. If you have a better idea, please provide it and explain why.

 

The 670 carb will work fine. The 195s will be okay too. But for a trail rig, I myself would go with a little smaller cam at .050. Like the 224/230 cam they have. But I would call and ask if they could grind it on a 112 or a 114 LSA instead of the 110 it is on. Give a little better idle and low speed manners for the trails. What kind of truck is this going into? Any reason you don't want to use the efi? For the price of the intake, carb, and distributor needed to replace the efi in a FI truck you could get a custom Stinger efi.

 

Thanks for the info!

Going Carb because it is simpler. Trying to get away from electronics as much as possible. Bugs in electronics are hard to source/find.

This is going in a Bronco II that I have done a full size Dana44/9” solid axle swap.

yeah, I mis-typed the cam I want. Looking at the 224/232 Extreme Energy CompCam offers. That has the 112 LSA you mention.

 

The cam you are looking at is for a 5.0 not a 5.8. I know the firing order is different and this may be an issue. Another potential issue is the cam is for a roller block, which you will want to make sure you have before ordering. Most cams require different valve springs, there is a page on comp cams website for the parts you will need with the camshaft.

Sounds like a sweet build, good luck!

 

IMHO, 1st avoid selecting parts yourself and go off the recommendations of the machine shop- with all the buyouts and issues that have occurred over the past 20 years, they will havethe BEST info on what brand of parts to get what from- and they will most likely give to a better price on them than what you could get buying them yourself! In many cases the oem heads are of better value than going aftermarket- especially with the QA issues.

Secondly, 1) avoid Comp Cams like the plague..... I will explain later on, but with regards to cams...

Considering the cam has such critical importance to the engines performance and life, to me it makes sense to use a cam grinder who will talk with you directly- even modify the cam grind to fit your needs even better and to address the possibility of cam lobe failure with the new oils. When it comes to making an engine breathe, there are so many variables including elevation, humidity, fuel blends/available octane, most cam mfgs will vary a "core grind pattern" to match the external impactors in addition to the internal impactors- which today IMHO makes the different between and engine that runs well, to one that just seems to run a little bit better, smoother and gets better mileage than expected. With regards to price...the difference is nil- especially considering its cheap insurance to know exactly who is machining such a critical part for your engine. And remember, advertised lift/duration/lobe separation is just that- advertised and not the specific grind including ramp profile that is used on the cam. If you are west coast, I highly recommend Iskenderian (who I personally know to this day physically tests/inspects every single valve spring before it leaves the shop and has the most tech advanced camshaft grinding equipment in the US) & Crower & Chet Herbert & Lunati are all good as well...all are family owned, been grinding cams for decades, and both will even re-grind your oem cam if possible- saving you even more $.

Comp has by appearance - seems to be a company that has experience more cam lobe failures than most and places the blame on the low ZDDP in the oils. Is it a factor yes, but I highly suspect that they are also using Chinese cam billets & they do not include Parkerizing their cams (Parkerizing is the final step and a crucial step to help break the cam in- a heated acid bath that microscopically etches the metal surface and adds a very thin layer of graphite coating which allows the cam lube to hang onto and penetrate into the cam surface during cam break in) unless you specifically request and pay additional money for it.... and Parkerizing is required for any/all cast iron camshafts (as compared to steel billet camshafts). Comp Cams was originally owned by an attorney in Huntington Beach, California- they treated the high end pros like "kings" but the "common guy", they literally just threw parts out the door and didn't care nor would they backup the customer. Harvey Cranes son went o work for them but didn't last very long and a couple of years ago a Private Equity Firm bought the company along with Edelbrock and holley.Specific to Comp and to validate this point further as to the “McDonald’s environment” of which operate:

Tech Support Issue:

http://saacforum.com/index.php?topic=901.10;wap2

Valvetrain Failure:


Classic Cam Failure:

http://www.hotrodders.com/forum/more...ure-48577.html

Cam Lobe Fracturing:

http://www.yellowbullet.com/forum/sh...d.php?t=458553

Cam Failure:

http://www.camaros.net/forums/showthread.php?t=121078

FAIL Comp cams trunion- Rockwell hardness low:

http://www.corvetteforum.com/forums/...n-upgrade.html

2nd Cam Failure:

http://www.performanceboats.com/gn7-...p-failure.html

Major problems with Comp Cams hydraulic roller lifters :

Major problems with Comp Cams hydraulic roller lifters

COMP CAMS FAIL (endless)

http://truestreetcars.com/forums/gen...cams-fail.html

Comp Cams Ultra Gold Aluminum Roller Rocker Failure

http://www.ls1gto.com/forums/showthread.php?t=388981

Comp Cams 918 spring failures

http://www.camaroz28.com/forums/ls1-...ilures-526319/

Now let's talk about cylinder heads.....


Heads- Aluminum vs cast iron

IMHO...Edelbrock parts- nothing really good or bad about them, they are middle of the road as compared to what is available. in general...aluminum is lighter, dissipates heat faster which typically means can take a hotter burn/more advanced ignition timing, but Cast iron will handle a lot more heat longer without warping....and typically handle higher cylinder psi. If your heads are in good shape, just needing a rebuild, yes, you can probably get almost the same performance (as long as you are not turning over 5K rpm) for a lot less $ than the al heads will cost.....but this is also area dependent too......

The 1964/early 65 heads flowed the "better" of most of the years as beginning in (end of year- depending on supplier) 66', they began slowly reducing flow. The oem heads are very, very capable of supporting up to 300+ hp...is it the most cost effective, not always however, with just about every one of the popular cylinder head (aftermarket) mfg going to china for their production, the quality is absolutely terrible...resulting in valvetrain failures, seat failures, etc. This vid by David Vizard validates everything I just said regarding the performance potential of the oem heads…. And that us old timers have known and done for years.


There is a reason the pricing is so "competitive", if you disassemble almost any of the brand new al aftermarket heads, you will almost certainly find valve surfacing is either poorly done or non-existant, seats....poorly inserted & finished ....and the ports.......not as bad a oe but has some unfinished business that when you pay $1k or more you should not be seeing.....and typically, if you take it to a machine shop for testing...most of the time there are defective machine work that is so bad, it requires re-machining the heads.

Please don't think for one minute, that any of the mail-order crap today is really worth the $ in comparison to buying a set of al heads and having them machined & built yourself. These vid’s really says it all IMHO........



Trickflow and AFR are ones that I would consider, but with the RPM you are turning, unless there is a need caused by head damaged, the oem heads would be your best $ for $ spent with a good machinist.

Ok, I'll shut up now (: HA!

 

Thanks for all of the information! That is a lot to take in and ponder over. The machine shop is planning to use Bullet cams, ever heard of them or had experience?

 

Haven't heard of them but I am SoCal kid!

 

Bullet cams are or at least when I was racing alot were good cams. Based on the old ultradyne cams. Just make sure that if the engine shop is ordering the cam, they spec it right. Tell them you don't need or want and 6000+ rpm cam. Mid 220s@.050 on the intake at most. I get nervous when a rebuild place wants to use their 'cam guy". And while I will say the old bullet cams were good. There is no guarantee that you won't get a cam that was left laying on the shops shelf that they just want to get out of their way. I've seen it happen before.

 

I really appreciate all of the valuable wisdom and help you all have provided! Thanks for helping me out!

 

I don't think I'd put afr 195's on a 351 truck build, especially for trails. If they're offering them to you for half the price of a set of 165 or 185's, then yea, go with them.

 

Is this the camshaft?



What camshaft did you find that is for a 5.0L? The one I found is a roller cam and starts with “35” so that has the 302HO/351W firing order. The block is from a ‘96 so it should be a roller block unless it was replaced with something else.

 

I think if the price is right he could get by with them, as long as he cams accordingly, otherwise yeah the 185s would be a better choice. Look at the LS 706 heads, those heads flow stock close to what the 185s flow.... and they are on a 4.8/284 engine. Just need a cam that makes peak power low so you get good cylinder filling in a usable rpm range. Heck if he could get a cam cut with like 212/226@ .050 and .550 on both for lift he could get a ford copy of the TruckNorris cam and that would make pretty decent power up to 5500 and good tq down low.

 

I was running a Holley 670 Street Avenger as the street carb on my 9.4:1 393W. Just a Comp X4262H Xtreme 4x4 grind flat-tappet at first (since I had to maintain emissions-sniffer-test compliance), but once that was age-exempt, I went with a Comp Retrofit Hydraulic roller XR276RF-HR (Part # 35-424-8) and 1.7 rockers to achieve .545/545 lift, 276/282adv, 224/230 dur a .050 that's a 1800-5800 in a 351, so drop that down a bit for my bigger inches... Note that Comp has that same cam for OEM roller blocks with the part number 35-428-8

 

Cool! Thanks for that info and thanks to everyone that has responded and given me help!

 

The "big port" heads on the LS engines are a result of the "advertised hp sells" motto that the engine designers have to take into account (meaning it's ok to sacrifice some low end), AND they have the advantage of using a long runner EFI intake manifold to increase inertia of the intake charge to make up for some of the loss in velocity that resulted in them shooting to achieve a marketable hp figure. I am an advocate of big port small cam for truck engines, but in his case, running a carb intake on a trail rig, he will definitely be feeling a larger diameter intake runner in the head.