351c Build Suggestions

[TheJ]

Hey guys, This may have been covered before but I can't seem to find some info for my 351c build. I bought turtle5353's reworked 2v heads and I am looking to make the most of them. They have new guides, hardened seats, 3 angle valve job, new springs, new valves, they were decked, milled and tapped for screw in studs, and had port work done.

My goals for the car are a nice street car that I can have some fun with. Maybe 350-400hp at the crank.

So here are my questions, most of them are newb questions:

What are some suggestions for a cam? (I am running a stock converter and plan to put either 3.25 or 3.50 gears in the rear end) I know some of you guys have used camquest to help but it keeps timing out and freezing on me.

I need screw in studs and guideplates, any suggestions for these?

As for rockers, what are the advantages of a full roller vs a roller tip? I found this company (probably chinese) called PRW, has anybody heard or used these?

What material of headgaskets are good to use?

Can I reuse the head bolts or are they torque to yield bolts?

Thanks for looking and sorry about the lengthy post.

 

[cazsper]

400 hp at the flywheel should be fairly easy. The following should get you right there:

9.5:1+ compression

224/232 @ .050 (flat tap or hydraulic roller)

Your heads

Edelbrock RPM or Air Gap intake manifold

3.25 gears should be fine but 3.50 will give you a bit more for low end and should be fine for the freeway. If you ever plan an overdrive or 5-speed, definitely go with the 3.50's

 

[TheJ]

Thanks for the reply, I forgot to mention that I'm not doing a full rebuild right now, just swapping the heads and intake and I'm on a tight budget. I haven't decided on swapping the cam yet because I want to take a look at the one that's in there first but I just want to get some ideas.

 

[Totalled]

Don't fear the gear. Also, go conservative with cam (generally) but don't put a truck cam in it either. Are the heads tapped for 3/8 or 7/16 studs? Are you gonna run stock 5/16 or 3/8" pushrods.... Determines on what studs and guide plates you get.

 

[TheJ]

Heads are tapped for 7/16, turtle5353 gave me a set of 5/16 pushrods but I don't know if they're the right length yet. What are the advantages of a bigger pushrods? I was looking at this cam but I'm not sure about the stall speed of the converter: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=848&sb=2

 

[cazsper]

I understand you're just swapping the heads and intake. I just wanted to show you how easy 400hp really was. The cam specs I gave you are good for 1500-6000RPM. Your cam may be a bit much for 351 inches with and 3.50:1 gears. Unless you want an upper RPM engine. Just figure out what you really want from your engine/car and then backwards plan.

 

[TheJ]

Oh ok, I don't know what the stock compression ratio or volume of the combustion chambers (especially since the heads have been milled). As for the cam I don't know too much, just looking around. I guess I'll have to decide what exactly I want out of the car.

 

[cazsper]

Well, the Edelbrock Air Gap is said to do well with the 2v and 4v heads. It's more of a high-rise but it's a dual plane so it will give you better low and mid range than a single plane. As for your heads, I guess you just have to figure what size the chambers are that you have and what the new ones are.

 

[Tnfastbk]

Call Comp cams and be honest with them on what you want and the will walk you through the process. I would stick with one brand or make sure all components work together (cam Kit) should be a very easy number to hit.

 

[clevelandcoupe]

Two items,

Keep in mind, especially in Wisconsin, an air gap manifold has no cross over provisions for exhaust warm up and will be very cold blooded.

I had at least (4) of 16 PRW roller tip rockers go bad. I believe it was a heat treatment issue and they are Chinese.

I would suggest going with a good name like comp cams or crane. I am using crane roller rockers with no issues.

Thanks, Jay

 

[Mister 4x4]

I've also got a 351C-2V and have punched it out to what CompCams CamQuest says should run around 400hp.

- Rebuilt the 351C-2V with:

-- .060" bores w/9.5:1 Keith Black hypereutectic flat-tops

-- CompCams Roller cam - not too wild, 274/274 @ .566 lift (which works out to 218/218 @ .500 lift)

-- CompCams 1.73 High Energy roller rockers

-- CompCams roller lifters w/spider guide

-- CompCams High Energy push-rods & rod guides

-- Crane Cams 7/16" screw-in rocker studs

-- 3-angle valve job & hardened seats (rebuilt the stock 2V heads)

-- Edelbrock Performer intake

-- Edelbrock Performer 600CFM carb (might go to 750... maybe)

-- Holley "Black" electric fuel pump

-- Mr. Gasket fuel pressure regulator & gauge

-- Chrome 'stock' oil pan w/Canton windage tray

-- Duraspark II ignition module

-- Accel Super Coil

-- Accel 8mm wires

-- Hooker Competition Ceramic-coated Long-Tube Headers

-- Pype 2.5" stainless exhaust w/X-pipe - Pypes Violator mufflers

Once the engine's broke in, I'll be swapping the carb for an Edelbrock E-Street fuel injection system - I'm used to not waiting around for a carb to warm-up, and mine will become a daily driver.

I also went with the Edelbrock Performer intake because I actually want to use the Ram-Air feature that came with the car.

All of that will be ahead of an AOD and a 3.00 9-inch. My intentions are to get decent fuel mileage and have enough power on-tap to have some fun now and then - which I think will work just fine with the things I have going on. If the 3.00s are too much, I'll swap in some 3.54s or similar, but having done gear swaps based on tire-size and lack of power, I don't think this car will have any problems moving along.

I know a lot of people are going to give me crap about the engine being bored .060" over - but it is what it is and what I had to work with. I'm not planning on racing my car so I think it'll be just fine. As long as the oiling and cooling systems are working properly, the whole 'thin-wall' heat issues won't be an issue.

 

[TheJ]

Thanks for all of the help guys, I forgot to mention that I have a Edelbrock Performer intake. I tried giving Comp Cams a call but got a busy signal three times. I'll try again later.

 

[marks73]

Try this sight and plug in the numbers.

http://www.compcams.com/downloads/register.asp

 

[TheJ]

I tried that but for some reason it wouldn't suggest a cam and didn't have any in its library. The online version works for me, sometimes. What is the stock compression ratio of a 351 2v and what would a Edelbrock Performer intake be considered high flow or max flow?

 

[c9zx]

In 73 I believe the CR for 351C 2V was 8.0:1. Between the 8.0:1 CR and standard stall convertor the cam is going to need to be pretty conservative. Chuck

 

[TheJ]

What would a good conservative cam be, I may just stick with the stock cam for now until I get some more time and money. I need rockers but I'm not sure of the advantages of a full roller vs a roller tip.

 

[cazsper]

For conservative, I would think something like 220/228 @ .050. As for rockers, I would assume the full roller would have less friction and free up some HP.

 

[Mister 4x4]

For conservative, I would think something like 220/228 @ .050. As for rockers, I would assume the full roller would have less friction and free up some HP.

I'm not entirely sure what the factory cam specs are for a 351C-2V (I think it's in the 170-ish/170-ish @ .480-something lift), but the cam I picked being 218/218 @ .500 is 'middle of the road' on CamQuest's range of 'out-of-the-box' cams. The description is something like 'optimal street performance, slight choppy idle.' The next cam on the list starts getting into race cams.

Just a tad more than 'conservative,' I'd say.

 

[c9zx]

What would a good conservative cam be, I may just stick with the stock cam for now until I get some more time and money. I need rockers but I'm not sure of the advantages of a full roller vs a roller tip.

There are a lot of unknowns here but, I'd say about 208-214 duration (I&E), .480-.510 lift (I&E), 112 LSA installed at 108. A 110 LSA will build power quicker and roll off quicker as well as have more overlap causing a rougher idle. A 114 LSA would have a smoother and somewhat wider power curve, have less overlap and smoother idle. If you use stock exhaust a small split, favoring the exhaust, may help a bit. Perhaps 4 degrees more duration on exhaust than intake and .010-.020 more lift. What ever cam you choose you must match the other valve train components to the cam. Mis-matched valve train components have ruined a lot of engines. The steel roller tip rockers would work fine and SHOULD be more rigid to maintain full lift of the cam. However, as with most parts these days the quality of the metallurgy and manufacturing is always a question. Unfortunately, these problems are not limited to just off-shore products. If you shop around you can find these for as little as $90 (DragTimes). Buy and use a checking pushrod and checking springs to determine optimal pushrod length. This maximizes cam effectiveness and and reduces valve train and guide wear. Given the circumstances, I'd put the gear in first to see how much it makes you smile then consider your next steps. The cam swap is not exactly cheap when you start adding up everything required to do it. Let us know what you decide to do and how things work out. Chuck