How can I get better performances ? 351 2V

I'm quite happy with the performances of my 72 Grande for everyday street cruising but I'd like to get "a bit more". Like many people, I wonder what is the "next step" to get a bit better perf something like 300 HP would be great.

Engine is a '72 351C 2V. I'm currently using a Weiand intake in this and a 600 CFM Holley Carb.

Exhaust is the original one but I plan to get some Hooker headers and a new exhaust kit with Flowmaster mufflers.

I think my engine is tuned correctly because the car runs great and it's cool to drive. I'm doing 0-60 in 8 seconds.

What do you think is the next step to get some more power ? 4V heads ? 650 CFM carb ? Stroked engine ?

Here in France parts are much more expensive because of the shipping and taxes, and used parts are expensive too, so I don't want to do a mistake. I know there are tons of things to do to get better performances, but I don't want a racing car, just a bit more fun to drive

Closed chamber 4V heads will boost your compression a full point but are costly and you'll end up putting in a cam, lifters,timing chain and gear while you'd have it apart. The 73 2v with the open chambers left a lot on the table horsepower/compression wise due to the emissions that started that year. Cost wise a larger cam and a good hot distributor/ignition set up will also be good. It depends on how much BETTER you're looking for.

What ratio gear set is in the differential now? Is the transmission and convertor stock? How important is gas mileage to you? The Hooker competition 2V headers are a good choice. Which high flow mufflers to select is more of a personal preference decision most of the time. I personally like the sound of something other than flowmasters. Assuming you have a 3.25:1 or numerically higher gear set, A cam lifters, timing chain set, and valve springs (and better rocker arms if the budget allows) would seem to be the next step. The stock Ford, multi-groove valves are notorious for breaking especially when the RPM range starts to climb. I would suggest a set of good single groove valves and keepers along with a high quality 3 angle valve job. Your new intake and carb would not be a good fit to the 4V heads and you would still need to buy all new valve train components. The 2V headers will not fit the 4V heads either. Based on what you have said you want and what you already have, I'd stay with the 2V heads and select a cam that is well matched to the total combination of parts you have ( compression, gear, convertor, intake, etc.). I'm glad to hear you are enjoying driving the car. Good Luck, Chuck

The above advice is good. You will get some additional performance with headers and exhaust. You will gain a little power (maybe) with an aftermarket ignition. You can improve your 0 to 60 times with a dual plane intake. Engine wise, there isn't much more to do except tune it. To get real performance improvement you will need to go with a different cam. This can be done with the engine in the car but it's easier if the engine is out. You can't go much bigger on your cam with out matching up the rest of the drive train and replacing the 1 piece ford valves. At some point you have to ask yourself if you want to go 'all in'? Replaceing the valves means pulling the heads and getting valve work done. So do you put money into 2v open chamber heads or go 'all in' and get some 4v or aftermarket heads. The cost goes up fast.

Additionally, if you get the 2v headers and a 2v dual plane then those parts cannot be reused (and they are not cheap)

Here is what I would do:

Decide if I want to build a motor or not. If so, plan out and buy parts for that motor while keeping the cost down on this one. I would leave the single plane intake and go dual exhaust but not purchase headers until I determined my final build and if I am keeping 2v heads, then get the headers.

If you decide that you don't want to build a motor then I would replace the intake, get some headers, put in a decent aftermarket ignition and swap out the rear end gears for 3.50's. If that doesn't give you what you want then go with a cam but keep the lift/duration at a reasonable level.

Sly, you really bring up an INTERESTING point which I do not believe is always taken into consideration when asking for (or giving) advice on issues like the one you seem to be trying to raise. It should be noted that "More Performance" is relative. Specifically, what is more (or better) performance in one person's mind may not be the same thing in another person's mind.

For example, are you looking for quicker acceleration or a higher speed over a specified covered distance? Is your car "running out of breath" when you want it to go "more" over a certain distance or in a specified time? The response to each of these questions could entail entirely different approaches.

Quite frankly, sometimes a simple change in rear end gear or final drive ratio can satisfy that alleged "need for more speed" which often equates to a "need for more quickness." Hence, the reason I believe Chuck inquired about the differential that you are using.

Most mass produced vehicles are built to address specific needs or desires of consumers. That is why we have Mach 1s and daily Coupes from the 1971 - 1973 Mustang period sharing the same basic engines (in many cases) why being configured somewhat differently. They each are designed for a specific market. It is pretty much about COMPROMISE.

With that having been said, it is much better to make a SINCERE assessment of how you want to utilize your Mustang MOST of the time. Once that is done, you can then address what specifically needs to be changed and/or modified.

Just a thought.

BT

Best bang for the buck 3.50 gears and a good dual exhaust. Then see if you need more motor at this point. My stock 351C 2V became more fun to drive when I pulled out the 3.00 open diff and installed the N case 3.50 T/loc diff. Or compromise 3.25s if you spend allot of time on the freeway.

Thanks a lot, this forum rules

I think I have many options right now as I can read.

Good dual exhaust is for sure the next investment. As Will said, if I plan to go 4V I'll wait to get the Hooker Headers.

Something like this to put in my Cleveland ? 1970 4V closed chambers heads

http://cgi.ebay.com/ebaymotors/FORD-351C-CLEVELAND-HEADS-351-C-4-V-CLOSED-CHAMBERED-/280748468882?pt=Vintage_Car_Truck_Parts_Accessories&hash=item415de9aa92

Will this fit ? Won't this play on the compression ratio ? 4V heads from before 1972 sound like a better base and not too exepensive to get a bit more HP. I will check out the 3.50 gears too

Performance is best achieved as a "Package", so don't think of as just adding a part here & there. Other than adding a 4bbl carb/aluminum intake and dual exhaust, the best bang for the buck is lowering rear gear ratio. If you go for cams, aluminum heads and other spendy parts, a lower rear ratio will be needed any way, to take full advantage of your investments. An overdrive 5 speed or AODE/4R70W will allow you those loer ratios with out having you turn 3200 RPM @ highway speeds. As for ratio, why limit yourself to 3.50's?? Go for 3.75's and then keep your fuel milage with an overdrive transmission. That is how the modern cars are done.

Yes I know, there's not one thing to change but tons of things, then it's a non ending race to performance and $$$. And needless to say more performance = more problems with engine durability, etc.

Overdrive 5 speed manual transmission would be amazing but they are very expensive especially here in Europe. Someone in my family used to have a 71 Coupe with manual transmission and he said it was very impressive !

So in the first place, in my case, what do you think of :

- lowering rear gear ratio ?

- buying 4V heads from a 70-71 Cleveland ? Then start from here to change parts in the motor (someday : pistons, cams etc.) ? I think I can find some good used heads on ebay and get them to ship here. Do you think I'll notice a difference with 4V heads, new intake and the same carb ? (Holley 600)

What rear gears do you have now?

Changing to 3:50 gears will give you more acceleration but also it will suck more gas on the highway (much lower kilometers/liter). Gas in France is not cheep.

Keeping the 2v heads would be better than 4v heads. The valves on the 4v are too big for street use. They are good for high RPM racing but 2v heads are better for low end power. Plus you'll have to buy a new intake to fit the 4v heads and the 4v heads will suck even more gas.

My suggestion is to get dual exhaust with good performance mufflers and retune your distributor for more and quicker advance. You'll have to use premium octane gas but you'll also get better gas mileage (better kilo/liter). You'll also see much better performance for not much money.

Thanks ! I will check out which rear gears I have. You're right, I think I will keep the 2V head because the main use of the vehicle is street cruising.

What do you mean by dual exhaust ? H or X ? I love the Flowmaster sound and from what I've heard on american cars around here and especially Mustangs I love the Flowmaster Delta 44 muffler which sounds brutal but not "too much". What about Pypes or Magnaflow ?? I never heard them for real.

Also should I get a performance distributor ? MSD looks cool.

Someone here advised me to pick up a dual plane intake manifold for better low end torque. Which one ?

Carburetor-wise, I'm happy with the Holley 600 right now and I don't think I should go for "more".

If you can post some products links to help me out, it would be great

Thanks a lot.

http://m.summitracing.com/parts/EDL-2750

Here's an edelbrock 2v dual plane square bore. If you like edelbrock...

With the stock cam I agree with Valhallo. If you extend the RPM range an additional 500-700 RPM by installing a more aggressive cam I'd consider the Edelbrock Performer RPM. If yo are considering a different cam there are some things about the 2V heads you need to know. With a stock 2V head and stock intake valve the intake flow stops increasing at about .410 inches of lift. With a larger (2.08 inch) intake valve and a good valve job that number will increase to about .450 lift. So there is no point in selecting a cam for stock, or near stock, 2V heads that open the intake valve much more than .450. The exhaust to intake ratios are very good on the 2V head so there is no need for a split duration (more exhaust than intake), split lift camshaft (more exhaust than intake). In the RPM range we are talking about the X and H pipes will be about the same power. The H will rumble more at idle and the X will sound more raspy above 3000 RPM. Chuck

Thanks ! I will check out which rear gears I have. You're right, I think I will keep the 2V head because the main use of the vehicle is street cruising.

What do you mean by dual exhaust ? H or X ? I love the Flowmaster sound and from what I've heard on american cars around here and especially Mustangs I love the Flowmaster Delta 44 muffler which sounds brutal but not "too much". What about Pypes or Magnaflow ?? I never heard them for real.

Also should I get a performance distributor ? MSD looks cool.

Someone here advised me to pick up a dual plane intake manifold for better low end torque. Which one ?

Carburetor-wise, I'm happy with the Holley 600 right now and I don't think I should go for "more".

If you can post some products links to help me out, it would be great

Thanks a lot.

Click to expand...

Dual exhaust is 2 exhaust pipes coming from the engine and going out the back. The 2v engines usually only had a single exhaust pipe. Giong duals will give you alot of power.

A "H" pipe or an "X" pipe do the same thing. They are a small pipe that connects to 2 sides and will add some power by balancing the 2 sides. I think the H sounds better. I also like the sound of Flowmaster 44s, and it's not that loud. They did add noticable power than the quiet stock mufflers.

Put an MSD if you want to spend money, but if the stock distrib is running fine I would just add a Pertronix I kit (pertronix.com) to get rid of the points. Then switch to high octane gas and work on the advance. More advance equals more power and better KM/Liter. Lighter springs will make it advance quicker.

I know you just bought that 2V 4 barrel intake from Summit. Get up with Crane Cam and give them the Intake, Carb, and Exhaust information you have and what your performance plan is to run and they will recommend a great fit camshaft for you.

As for the exhaust, the X or H pipe lets it breath properly and adds to the proper back pressure for maximum performance. They need to know or can recommend the diameter piping and mufflers depending on your driving wants.

Yes I know, there's not one thing to change but tons of things, then it's a non ending race to performance and $$$. And needless to say more performance = more problems with engine durability, etc.

Overdrive 5 speed manual transmission would be amazing but they are very expensive especially here in Europe. Someone in my family used to have a 71 fastback with manual transmission and it was very impressive !

So in the first place, in my case, what do you think of :

- lowering rear gear ratio ?

- buying 4V heads from a 70-71 Cleveland ? Then start from here to change parts in the motor (someday : pistons, cams etc.) ? I think I can find some good used heads on ebay and get them to ship here. Do you think I'll notice a difference with 4V heads, new intake and the same carb ? (Holley 600)

Click to expand...

I woulent do any engine mods untill you have added(in order of preference) Dual exhaust, 4bbl carb & aluminum intake( like Edelbrock or Weiand), and a good set of headers. Then, lower the rear gears. I understand that n OD trans can be expensive, how ever, My fuel mileage went from 17 MPG to 22 MPG after; Building a performance 5.0, switching the rear gears from 3.01 to 3.25 and adding a 4R70W automatic transmission. 5MPG @ Euro fuel prices can add up. And I got a huge increase in Performance. I plan to use 3.75 gears later, but 3.25 is what I had on hand.

As far as what heads to use, if you have a Cleveland, get a set of Aussie 2bbl heads. They will give you much better street torque tha American SBF 2 or 4 bbl heads. Given my choice, I'd look for a roller 351 windsor, though a donor in EU would prolly be hard to find.

Thanks that's amazing input, I already have the 44bbl carb and aluminium intake working properly so that's a good base Next step is definitely good dual exhaust and Hooker headers. Then rear gear ratio.

Exhaust-wise, What do you think of this ?

http://www.leboncoin.fr/equipement_auto/241515447.htm

It's cheap, in France and looks like THRUSH, but not sure.

Flowmaster 44 mufflers are a dream though.

And dont be afraid of open chambered 4 v heads...you will get alot less ping ... They are much better for todays fuel and will flow up too 800 horse power or more if needed<~~i know some closed chambers fans hate the open 4v...but really...they will do just as well and flow more than you will ever need.....how many pony's you wanting? them 2v heads are good up too 350 or 400ish..any more than that you should look into 4v heads....cam is a big helper and headers like said above...i got a 4v cleveland with open chambered heads....im putting a 5:25 lift cam...hooker headers...750 holley vacume sec....and even if i leave my stock 9.1 compression..im expecting about 425ish....with 10;1 im expecting around 450 horses...sence mostly you can get only 92 octange around here im not going to high on compression....with a 600 cam lift...you would expect around 550 hp...but any more than that..you will have to get a 4v block to go long with your 4v heads....2v's are usualy 2 bolt main...And anything over 600ish hp should have 4 bolt atleast...sence clevelands spin so many rpm's .

Thinks ill become the unofficial spokes person for the 4v open chambered heads... Sence not many stick up for them hehe

I agree with most of the post but have to disagree with the following "but any more than that..you will have to get a 4v block to go long with your 4v heads....2v's are usually 2 bolt main...And anything over 600ish hp should have 4 bolt at least...since clevelands spin so many rpm's ." As most 351c 2 or 4v blocks are 2 bolt mains. All can be modified for a 4bolt main set up, but in my opinion its not needed.