Opinions wanted on a 351w build...

[cavboy78]

First off, I am a long time lurker and just wanted to thank everyone in advance. I have learned a tremendous amount from all the great experience and knowledge on here. I just wanted some input on an engine build I am starting. Some quick background: The engine is going into my 70 sportsroof and will be mostly a weekend warrior/occasional drive to work on nice days. I currently am running a T-5z. I am putting a 9” rear in with 3.73 or 3.89 gears. I just recently bought a F4TE roller block out of a ’94 Lightning. The PO ran it shortly in a turbo’d configuration. As a result, he kept the stock crank/rods, but installed forged pistons and an F303. Block has not been bored, cylinders have been honed though. I am going to talk to a local builder tomorrow and this is what I am currently leaning towards. I just wanted a sanity check first. If I have listed more than once choice, I put them in order of preference.

Pistons: L2446F (compression=9.19 at 60.4 cc)

Heads: AFR 185 (w/ upgraded valve springs) or Vic Jr.’s; I could not find a TFS head with a small enough combustion chamber to keep by compression up. I figured a 58/60cc chamber will get about 9.4:1 or so.

Cam: XE274HR or TFS2 or Z303

Intake Manifold: RPM Air Gap

Carb: Eddy Thunder AVS 650 or Holley 670 Street Avenger

Rockers: Comp Cams Ultra Gold or Pro Magnum (7/16” stud)

Let me know if any other information is required. Thanks.

 

[rbohm]

i like your build with one change, i would go with a head that has a 200-210cc intake runner. you can always mill the heads to get the compression ratio back up where you want it. most of the larger runner heads have a 64 cc combustion chamber.

 

[NasaGT]

Will the Air Gap on a 351w fit OK in a 69-70? I would like to do a similar build for my 69, was wondering if the air gap would work or not.

 

[cavboy78]

rbohm, thanks for the input. Understanding I should look for a larger head...but should I also try to stay at a 2.02" valve just for the sake of not losing the low end? It looks like most of the larger heads jump up to a 2.05 or 2.08 valve as well.
Nasa, I have seen Air Gaps on 69-70's with 351w's. I think a drop base air cleaner would help for any clearance problems. My hood has the Mach scoop on it that the PO put on it. My plan is to get a K&N X-stream air filter which has an open element on the top. Then I am going to cut a hole in the hood where the air filter is and turn it into a functional scoop.

http://www.summitracing.com/parts/KNN-66-3150/

 

[brianj5600]

With the cam and intake you have listed I would go with a GOOD 185cc head, AFR or Trick Flow. If you are worried about loosing bottom end, the 20 extra cc's in the port will kill more than the .03"-.06" of the valve. Most 2 valve heads have a smaller than ideal intake valve because of real estate in the chamber.

 

[rbohm]

the nice thing about the 351w is that it isnt as sensitive to larger ports and valves as the 302 is, so if you like a set of heads that has a 200cc intake port, but has 2.05 intake valves, go ahead and use them, they will not be an issue, except perhaps in regards to piston to valve clearance, and if you are not checking that, you deserve to have a valve bust a piston.

 

[cavboy78]

it seems as though the vic jr's have a 210cc intake runner and a 2.05 valve but they flow more comparably to a 185 head. if that is indeed the case, they should be crossed off my list. Of course I'll check PTV clearance Also, i am expecting a slight lope at idle. please correct me if i am wrong...understanding that slight lope is open to individual interpretation

 

[htwheelz67]

especially with your cam and compression a super large head is overkill you wont see much if any gain untill 5-6k, the 185 is perfect but I favor twisted wedge heads the std 170cc works perfect on a 351w BUT the as cast 190cc TW head are the hot ticket, if you are going to dissassemble the block then deck the block to zero and then mill the heads (TW heads are 61cc) to get your compression up. I decked my 94 block for my 408, as far as the cams you listed the xe274hr is about the best of the bunch, even though the TFS cam looks the same it is not the comp has much quicker ramps but the TFS is a bargain, the z 303 will like about 10+ compression, the XE cam will give a nice lope and give excellent low end as well as top end for a slight charge you can have comp grind the cam on a 108LCA and it will add more to a carbed car. Carb the Avenger is better than the edelbrock but a demon is better than the holley for the price (650 cfm) and will flow much more air.

 

[68stang351]

I'm running twisted wedge heads in my 68 coupe with a XE284 cam and a Performer RPM and a Holley 780, and a T5, and it runs pretty good. Mine is also a fairly low compression motor which is why I'm throwing some spray on it, but I have to wonder how it would to withs some 190cc TW heads. That's what I wish I really had.

I only put the TW 170's on because I got them never installed for next to nothing for the 302 in my wife's car but at the last minute I decided it was time to get rid of the stock heads on my 351, so I stuck them on there along with that XE284 cam. It runs really good from about 3,500 rpm up until around 6,000 then kind of peters out. However the exact same heads on my buddy's 302 run good until about 6,500, which makes me wonder if I need more airflow from the heads for the windsor.

I'm no expert but this is just what I've observed from my short experience dealing with heads and windsors. People like Brian and Rbohm are way more knowledgeable, but this is what I've seen so far.

If I was going to buy a brand new set for my combo I would buy something in the 190-205 range.

 

[brianj5600]

I would not do a spring upgrade either. Chances are they will be wrong. Get springs that are made for the cam you buy.

 

[blown65]

I think Canfield makes a 58cc head.

The victor jrs are 64 cc I believe. I had mine milled and ended up at 59cc.

 

[cavboy78]

htwheelz67, thanks for the input on the cams. I did assume the xe274hr and tfs2 were almost the same. Pardon my ignorance too, but what is the advantage to that particular cam with a 108 lsa, to help out on the low end?

When you talked about the TFS heads, were you talking about the Track Heats/Twisted Wedges or the Hi-Ports? I do have a new set of Performer RPM's that i originally bought for a 302 build, but figured they would be too small for the 351w to make it worthwhile to build instead.

And just a general head question...i am most likely going to redo my complete exhaust since it's a true dual with some old mufflers. does the raised exhaust port really matter that much then? i saw both canfields and tfs heads are.

brianj5600, i agree that matching valve/cam combo is ideal. I think that the comp cam is the way to go and will call them once i decide on heads to determine what is a match. thanks.

 

[blown65]

The Victor Jr are a raised port also, thats what I run on my car and it doesn't cause any problems.

 

[cavboy78]

Blown65, if I did want to buy Canfields, should I go through jay at camshaft innovations? and thanks.

 

[htwheelz67]

I may be wrong but I think the only difference between the track heat and regular twisted wedge is the track heat is a non emmisions head and no exhaust crossover. Canfield is a great head but somewhere I heared they are out of business, Speaking of Jay Allen, you may want to spend a few bucks more on a custom cam designed for your combo, jay did my cam for my 408 and it does exactly what I wanted, a custom cam can really help drivability yet make the power you want. If you already have a set of RPM's a bit of porting and a custom cam can net some good performance. The 108lca seems to work better on the xe274hr, a cobra guy I know rebuilt his 347 and dropped to a 108 lCA on the same cam and it was stronger on the dyno than his previous same cam/combo, his builder recomended it. If you already have the shortblock and need to freshen it up then go a 393/408 to start with as you will want more after the 351w. Been there done that and now with my 408 I want more and you will too.

 

[blown65]

Blown65, if I did want to buy Canfields, should I go through jay at camshaft innovations? and thanks.

I wouldn't. Quite a few have had problems with Jay of late.

If you can deal with Jays arrogance, more power to you. You may as well just send him money and give him the specs and not question a thing he says. He may know his stuff and get you the right cam, but he is an ass to deal with IMO.

I'd rather deal with Ed Curtis at flowtechinduction.com/ Much more willing to talk with you and not slap BS back at ya. Plus he does head stuff etc etc. He is working on my new cam stuff right now for my new build.

Or you could talk to someone like Duane Busch at hardcore50 and get some advice and service as far as head work and camshaft selection. Mine runs pretty good now and I attribute it to Duane's help.

 

[cavboy78]

I also think the track heat has upgraded springs. I'm not sure if jay's page is outdated, but it still shows canfields on there. Either way, I plan on calling him this upcoming week. Out of curiosity, did you get a billet or sadi cam? As for the shortblock, I am at most just going to put fresh rings on it. I am worried about the t-5z behind the 351w let alone a 393w. I think I will stick with what i have for now, save some money, and then upgrade tranny and stroke out to 393w a while down the road...at least that's the plan That's also why i plan on moving to a larger head now then the Performer RPM. And thanks for the insight on the xe274hr on an 108 lsa...all things to think about tonight.

 

[blown65]

I also think the track heat has upgraded springs. I'm not sure if jay's page is outdated, but it still shows canfields on there. Either way, I plan on calling him this upcoming week. Out of curiosity, did you get a billet or sadi cam? As for the shortblock, I am at most just going to put fresh rings on it. I am worried about the t-5z behind the 351w let alone a 393w. I think I will stick with what i have for now, save some money, and then upgrade tranny and stroke out to 393w a while down the road...at least that's the plan That's also why i plan on moving to a larger head now then the Performer RPM. And thanks for the insight on the xe274hr on an 108 lsa...all things to think about tonight.

You might wanna do some reading the the cam section on yellowbullet on how ppl are liking Jay right now and his cam delivery timeframe. I know its because his health isn't well but you may want to rethink that.

 

[blown65]

Jay Allen "Camshaft Innovations" - Page 17 - Yellow Bullet Forums


Started at the end but do some reading and spare yourself the headaches of dealing with him.

 

[rbohm]

another good place to go if you want a custom cam grind is clay smith. they do the cam grinds for classicinlines.com.