2v engine setup

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M Beauchamp

Well-known member
Joined
Aug 15, 2011
Messages
392
Reaction score
5
Location
Sarnia Ontario
My Car
1973 light blue convertible
351c 2V
Now that the body work is getting some what closer to the end!

I am starting to think about the engine build and hopefully pick up engine parts while i finish the body.

I though I had a line on a set of 4v heads but that didn't pan out.

After doing some reading on the 2v & 4v engine set ups, it apparent that the 4v is best suited for serious HP but not very good for the street.

The 2v can be set up for better for low end torque and better suited for the street.

So this got me looking at the different 2v set ups on the site.

With the myriad of carburetor, cam, header, ignition, etc, combinations, what really works and what doesn't work.

So could some of you who have gone threw the learning curve give me your advise.

Is the 2v the right way to go for the street

what is the best bang for the $

 
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In my opinion yes, stick with the 2v heads (since you have them already). The best dollars spent will be on an Edelbrock performer 2v and a 670 street avenger carb. An "RV" type cam is a good choice as it will fill the cylinders well and provide loads of torque at low RPM which is where a street engine needs to perform. If you can free up some budget money talk to the guys at Comp and have them set up a hydraulic roller cam for you. If you get a reduced base circle cam ground you can use Ford lifters and hardware to save considerable dollars. Light the mix with a duraspark distributor and an MSD. As for exhaust I do not beleive headers are worth using on a street engine (too much maint.) I am a firm beleiver in spending money once by determining exactly what you want in the end. If you want to race go with some aluminum CHI heads, they are proven performers.

 
+1 on what Jeff said. Call Comp Cams and tell them what you want to do with your car. They will set you up with a nice cam for your use, along with all the necessary matching parts that are mandatory.

Jeff is not fond of headers, and this is where I respectfully disagree with my friend. Getting the burned fuel mix out of the combustion chamber is almost as important as getting the properly ratio'd air/fuel mix into it, and I believe that headers are necessary to do that. Although the stock 2V exhaust manifolds might have been better than many back in the day, I still believe that aftermarket headers will provide better exhaust flow than stock.

Otherwise, I agree with what Jeff said with regard to street performance.

Doc

 
After doing some reading on the 2v & 4v engine set ups, it apparent that the 4v is best suited for serious HP but not very good for the street.
You are in for a beating on this subject...as am I.

I have personally owned and driven thousands of miles as a daily driver the following(in order of quickness):

70.351C .. 4V Carb & Heads 4Speed XR7...100% Stock

73.351C .. 2V Carb Auto Mustang...100% Stock

70.351W.. 4V Carb & 2v Heads Auto(Built from below with Mild Cam) XR7

70.351W.. 2V Carb & Heads Auto XR7 Stock

73.302.... 4V Carb, 2v Heads Auto(Built from 302 2V with Mild Cam) Mustang

I have never owned/driven/heard a 351C with 4V carb and 2v heads...apparently that is the only thing missing from my experience. I see lots of posts claiming how great this setup is, but I never come across anyone PERSONALLY that is doing this.

The fastest car by far was the #1, 70 351C 4V Stock. Very mild in idle at the line. But it was faster out of the hole, faster from 30-60, faster from 60-100(I understand gear ratios play a part in this as well...I am not a writer for Car Craft). I have no idea what anyone is talking about regarding "not meant to be driven daily". I wish I still had that motor and drive train today. I would drive it 60 miles round trip in rush hour traffic and never complain about it.

Like you, I am also in the middle of building my 351C 4V Quench Head motor. However, I am piecing together a motor from bits of iron bought from all over the country. I NEVER FOR AN INSTANT considered 2V heads on this motor, despite all the ranting and raving about them.

If you are as concerned about the time and effort you put into your motor as I am, find someone who has a car/motor you like and find out what they did. Here in SoCal, most everyone goes WAY to lopey on their motors for my taste. They do sound nice at 1500+RPM, but until then, they make an idling Harley seem calm and well mannered. Many guys here have huge cams, huge carbs, state of the art $$$$ ignition systems. God bless them, but that isn't me.

I could not find anyone with a motor I liked. So, I started my build with a 351 Boss cam spec(see my recent post regarding that subject). With everything written about that motor, I thought it was a good place to start. I am satisfied that the cam going into my motor, will be a little more grouchy at idle than a 351 Boss, but not too much. I doubt it will be as fast as the 351C 4V with the toploader as I am running an automatic, but we will see what happens. If it ends up being a close #2, and runs without problems, and is extremely loud, I will consider it mission accomplished...and a reason to install a 5 speed overdrive at a later time.

So, for what it is worth:

351W 4V Carb, 2V Heads, Stock 2V Exhaust Manifolds, FMX, 2.75 Gears, Isky 262 Hydraulic SuperCam

.445 lift at valve(1.60 Rocker Arms). 262 Duration, 108 Lobe Center,

Very mild, nice soft rumble in the cabin, sounds like a Mercury at the rear, not quick off line, but fast from rolling start. Gears too low and tires to big.

Soon

351C 4V Carb, 4V Quench Head, Headers of some type because the stock 4V manifolds will suppress the sound, C4, ??? Gears, Isky 264 Hydraulic MegaCam

.525 lift at valve(1.73 Rocker Arms), 264 Duration, 108 Lobe Center

To be determined.

Blah blah blah...good luck.

 
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ZGW all I can say is on the SS GT/D car we run 4v cleveland open chambered iron heads with BOTH intake and exhaust ports filled approximately 25% using a roush intake and a 750 vacuum secondary carb. 9.45 @ 146mph says it all in my book. The port volume on a 4V cleveland head is just WAY too big to maintain flow velocities.

Talk to any race engine builder with experience building clevelands. Look at the Roush / Yates heads. Ernie Elliott made tons of power with "pea shooter" heads.

Dont get me wrong, I'm not saying 2v heads are superior. They have many issues as well. The short side radius in the exhaust port is too sharp and you hit water if you try to fix it.

My point is for a mild street engine the 2V heads are the way to go. I believe that was the original question anyway.

 
M Beauchamp ...told you I was going to get into trouble...

Droptop73..."We run 4v cleveland open chambered iron heads with BOTH intake and exhaust ports filled approximately 25% using a roush intake and a 750 vacuum secondary carb. 9.45 @ 146mph says it all in my book."

I can't disagree with what you are saying. In fact, I respect what you are saying. My intention as a rookie 7173mustang member was to simply provide information of my personal daily driver experience, and what I want in my street car. Your point is he can save the money and be satisfied.

The point I make is, based on my experience, the bad rap 4V's get in regards to daily drivers, street machines, is WAY overblown. You recommend a 2V because you have a race car with 4V heads with filled ports. I recommend 4V heads without filled ports because I used to drive one on the street every day, I drove it thousands of miles(bought it stock with 60K and put another 60k on the original motor...using unleaded fuel(!)), and I would not take the chance of putting my time and effort into rebuilding the motor and having any second thoughts.

Will M Beauchamp be disappointed keeping his 2V heads and keeping a few hundred $$$ canadian in his pocket? Probably not... in fact let us say NO he will not be disappointed. He did say best bang for the buck.

Will he(assuming M is a he) be wondering how much better his car MIGHT(and I emphasize might) be if spent the extra $$$(let's guess $500c) and got the 4V heads and necessary exhaust? I would. But, to be clear, that is me. And right or wrong, in response to the question, "what type of heads do you have", no one is ever "wowed" over by the response "Stock 2v Heads." Although when you run a 9.45 quarter mile I bet they are!!!

Regardless of all the posts, I just can't help but wonder why the guys who engineered the 351 BOSS did not leave on the 2V heads if during the new car test drive the potential buyer would have been more WOWED over? Maybe they didn't know any better. Maybe we'll be lucky one day and find one of these engineers and he will tell us what they were thinking.


M,

For what it is worth, I have started a spreadsheet detailing EVERYTHING I need to get to build a 351C from scratch.

I am trying to make it absolutely thorough and complete, down to the thermostat bolts.

It is yours for the asking. Perhaps we could collaberate as it is really going to irritate me to no end if I am missing anything.



Or just send your check book and Jeff, Doc, Mark and myself will take care of the rest:D
How long would it take(Ouch!!!);)

 
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4V heads not being good for the street is a myth. My experience with the 2V and 4V is this.I ran 3 mildly built 2v motors in my 71 Grande and all they did was ping Them self to death.Sounds like a good street motor to me. The 1st 2v motor ran the best.It was very basic A Holley 600 Edelbrock performer Isky RV cam Headman headers and 3.50 gears.The 2V motors don't like big Cams.Ok know for My experience with the 70 4V motor. I had a bone stock 70 4V Mach1 with a FMX and 3.91 gears.The car ran very strong.Allot better than any of my 2V motors did.To bad the Mach1 was rusted out be on repair so I parted it out.I kept the 4v motor trans for my 49 F1 pick up.I ended up blowing up 2V motor #3.At that point I new it was time to make some power. So I had the 4V motor rebuilt.It was mild compared to today's specs. 30 over Ford motorsports cam Holley 750 DP Weiand X-celerorator intake unilite dis and all the hard wear to make it strong.Then installed it into my 71 Grande.Now the car was fast.Then pulled the 3.50s out and installed 4.11s. That took the car to the next level of fast.I didn't think the 4V motor stock or modified felt flat down low. To me it felt like the 2v motor gives up and the 4V keep going.My opinion is the 2V motor maid noise and The 4V motor maid power.

 
This topic always brings out strong opinions, as it should. There were two questions. Are 2V heads right for the street and what is the best bang for the buck? How much bang do you want and how many bucks do you want to spend are the questions that need to be answered and only the owner can answer them accurately. Apples to apples, the 4V engine will yield more bang for a few more bucks, especially if you are willing to bring the RPM up. The cost of rebuilding a set of 2v and 4V heads is about the same, the additional expense is the cost of the 4V cores. The cost of other components to rebuild the engine are the same. So, how much bang is desired? And what is the bang budget? What gear ratio can you live with?

Chuck

PS Best bang for the buck is usually a gear change.

 
This topic always brings out strong opinions, as it should. There were two questions. Are 2V heads right for the street and what is the best bang for the buck? How much bang do you want and how many bucks do you want to spend are the questions that need to be answered and only the owner can answer them accurately. Apples to apples, the 4V engine will yield more bang for a few more bucks, especially if you are willing to bring the RPM up. The cost of rebuilding a set of 2v and 4V heads is about the same, the additional expense is the cost of the 4V cores. The cost of other components to rebuild the engine are the same. So, how much bang is desired? And what is the bang budget? What gear ratio can you live with?

Chuck

PS Best bang for the buck is usually a gear change.
Chuck is dead on it. One rule to follow is how fast you go depends on how much money you want to spend

 
Chuck

PS Best bang for the buck is usually a gear change.
I agree with this...especially if you go from a 2.75 to a 3.25. Hopefully, I will get to find out first hand by the end of the year.

 
I just finished building a 351C 2V and wanted to build a motor that I could drive daily, but put my foot to the floor and leave 100' posi marks behind me at will!

I didn't want to get crazy with a non streetable cam that wouldnt idle, but I wanted something with a long range that would launch good and still pull hard at 6K. I went with a Comp Cam with 520 lift, just at the border and Comp did not require screw in studs, so it saved a little coin there. I'll double check, but I think the RPM range is 2200-6,500rpm. Perfect for my 2,200 stall converter.

I have used and built Holleys for years and performance and cost wise, there is no better carb in my opinion, then a Holley with Mechanical Secondaries. Barry Grant carbs are sweet too, but spendy!

The Holley Dp mech secondaries give you instant hole shot at any speed, and you can really dial them in to fit your driving needs. The only issue that you just can't get away from is the richness at idle. You can lean them up as much as you want, but they double pumpers just run best rich at idle.

I have a 4778 Holley(700cfm) and am still playing with jets, nozzles and settings, but so far it's a screamer and the little tweeks here and there are working nicely.

I love the Edelbrock/Holley/Comp Cam combo. They really match up well, and if you need to get tech help, they are all good at helping out.

I personally wanted a longer range and higher RPM since the 2V heads have so much top end, I wanted to exploit that, but also wanted a nice launch. So we went with the larger intake valves and the Edel. RPM Air Gap Manifold.

First thing I do is scrap the exhaust manifolds and put headers on. You may have to turn the header bolts a 1/4-1/2 a turn every 5-10k, but so what, they make such a difference in flow and you can't beat the sound. They are well worth it.

I have checked on many headers, from Hooker(made in Mexico now) to Motorsport, to Sanderson and for some reason Hedman fits the best and tuck up underneath the frame the tightest. They are also close to be the least expensive. There finish sucks, so I would recommend powder coating them before you install them, but other then that they are a breeze to work with and they don't hit on anything.

For mufflers, I went with Spintechs. I used to run a custom exhaust shop and stumbled across these years ago. For some reason these sound the best on Fords and they really sound good. The closest I can explain the sound, is like a Borla high rpm crisp and clean sound under load, then at idle, just a real nice rumble without the nasty resonation like you get froma Flowmaster, or other 2 or 3 chamber mufflers. I will never put any other muffler on a Ford other then a Spintech, they are just so unique. I get comments almost everytime I am sitting at idle from people asking what I have under the hood, thinking it's a pumped 429 or something stroked and crazy.

Anyway... some free useless advise to do with what you please..

 
Wow guys

2v or not 2v this is the question

hay , a lot of good advise

Its interesting to see so many different approaches on this.

Thanks guys

 
I drove my 4v open chamber'ed 351C on the street daily for a very long time. I never really understood the 2v is better on the street talk. The 4v has more than enough power/torque in any situation. Idles fine. Gets decent gas mileage for what it is. Hell I even run 87 octane gas in it.

Did I mention that my basically stock 4v runs just as fast as my 2010 GT?

If I were you, and had the cash, I'd go for the 4v setup. That's just me, I know there are people that know way more than I do about this stuff on this site.

I might see if I can score some 4v Closed chambers here soon for my car, bigger cam, etc. as I don't think my car is even close to "not streetable"

whatever that means.

 
For what it is worth, I have started a spreadsheet detailing EVERYTHING I need to get to build a 351C from scratch.

I am trying to make it absolutely thorough and complete, down to the thermostat bolts.

It is yours for the asking. Perhaps we could collaberate as it is really going to irritate me to no end if I am missing anything.

Wolverine, I'd be interested in checking out your engine build spreadsheet. My M-code engine is slated for rebuild at some undetermined point in the future. I think I'll add Spintech mufflers to the list as a consideration as well. ;)

 
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