351 cleveland: new build plan

[Omie01]

OK, here;s the new plan. I finally got my motor on a stand yesterday, and found that this engine was JUST rebuilt. (351 2v) Pistons are still as new, crank appears new, and all valve train looks new. I have a pair of 73 OC 4bbl heads that are back fresh from rebuild and would like to use them, (gift from my father). I have blown my whole budget on getting the car road worthy so dont have much $$$ for engine rebuild. I would like to build a stock style 72 CJ, using the original valve train, and most stock components. The rockers arm fulcrums are the steel ones, not aluminum! I guess my major concerns are: Cam specs, which cam would work best for this build? I want to stay with a hydraulic, but would like a little performance out of this motor. I will install new cam bearings for the cam, which are the best ones? Should I buy all new rocker arm bolts? Head bolts? Any other considerations I should take into account. Which aftermarket intake still allows for use of the ram air system? What size carb should I use for a stock 4bbl? Are push rod lengths different from 2v to 4v? Keep in mind, in a year or 2 I plan on doing a better build, this motor will just be for me to have something to use for a year or 2 while I save some $$$. Thanks guys!!

 

[TommyK]

You are going to be limited on cam choice due to the desire to reuse the stock valve train. In this case something like a comp 268h would be my suggestion. It will work with a stock valve train and converter (assuming automatic) and provide a noticeable power boost.

If the engine is recently rebuilt the cam bearings should be good. If an inspection reveals otherwise Durabond cam bearings are a good choice but I would probably use whatever your machinist recommends.

For what you are doing the stock head bolts and rocker arm bolts are fine.

a 650 or 750 cfm vacuum secondary carb on a performer intake will work well and fit with the ram air.

A word of caution. I have run both 2V and 4V clevelands. A 4V cleveland while not difficult to build does require a certain combination of parts to get the best performance. A half baked 4V build more often than not results in a dog which in my opinion is what has given the 4V cleveland the reputation of not being a good street motor.

I know you didn't ask but my advice would be to consider a simple cam swap on the 2V you have now along with a recurved distributor, carb and intake and save up until you can afford to build the 4V properly. It will probably out perform the "half baked" 4V build.

 

[Don C]

I agree with Tommy. The only thing I might do differently would be to install Tim Meyer cam bearings for improved oiling in the future, when you upgrade. His cam bearings eliminate the need for screw in restrictors. The stock Cleveland oiling system is fine for most of us and typically just needs modifications for racing, but these cam bearings are an easy and inexpensive upgrade when you're going to replace the bearings anyway.

 

[will e]

I agree. Sell the 4v heads and use the money on the car. (And I am a big 4v fan). But for what you want and your budget adding the 4v heads with open chambers isn't going to give you much more than bragging rights. Don't forget you have to swap out the exhaust manifold/headers too when you go 4v.

 

[barnett468]

what is your gear ratio?

is your torque converter stock? . . if not, what stall rating is it?

are your pistons flat on top or is there a dish in the center?

if your compression is less than around 9:1, i would try to get it to that or slightly higher if you plan to run premium gas.

i would run a comp xe268h instead of a 268h . . it will have more overall power . . if your gears are 3.00 or numerically less, i would run the next size smaller . . this cam likes at least 3.40 gears but you can also get away with 3.23 gears in a 351.

 

[Mustang Dynasty]

OK, here;s the new plan. I finally got my motor on a stand yesterday, and found that this engine was JUST rebuilt. (351 2v) Pistons are still as new, crank appears new, and all valve train looks new. I have a pair of 73 OC 4bbl heads that are back fresh from rebuild and would like to use them, (gift from my father). I have blown my whole budget on getting the car road worthy so dont have much $$$ for engine rebuild. I would like to build a stock style 72 CJ, using the original valve train, and most stock components. The rockers arm fulcrums are the steel ones, not aluminum! I guess my major concerns are: Cam specs, which cam would work best for this build? I want to stay with a hydraulic, but would like a little performance out of this motor. I will install new cam bearings for the cam, which are the best ones? Should I buy all new rocker arm bolts? Head bolts? Any other considerations I should take into account. Which aftermarket intake still allows for use of the ram air system? What size carb should I use for a stock 4bbl? Are push rod lengths different from 2v to 4v? Keep in mind, in a year or 2 I plan on doing a better build, this motor will just be for me to have something to use for a year or 2 while I save some $$$. Thanks guys!!

650 holley is safe but before a concrete decision a good autiority to speak to like A-1 machine shop that helped my man take a hydraulic lifters to a 9.5 compression with solid lifters but with an Edelbrock 2 barrel intake manifold with 3.5 rear ratio on my 4 speed to toploader higher torque ft lbs at lower mph dyno via passiue 3rd and 4th gear pulled a 289. Also check on xado.com engine treatment not a snake oil and a Holley 780 cfm 4 barrel will do increase the hp and torque with better compression increase without all the upgrades of fuel addivies as methanol and supercharging an extravagant expense and xado guarantees nowear on motor for @ 40,000 miles of hard driving. Just premium gas and oil with lead additive. Get back to me if any of this pans out.could luck out and if u want to maintain its same cóndition in 2 years as it is when put together now. Ie A-1 machine shop Greensburg, PA whom did a lot of work with a guy whom use to do a lot of upgrading specializing in cleveland engines


they are all correct and a combination from the headers size xhaust pipes to minimize back pressure~see my profile and photo album for further ideas to tweak hp even an open K & N fllter system in the ram air set up...


pss check out closest hard copy on my expansions per se on my profile and 300 photo album. Not saying I am an authority but the guy that worked on my engine was and raced the circuit with his clevelands back in a day in Pittsburgh but passed on back in 09. Mark Brewer-Motorwoiks, Greensburg, PA

 

[Omie01]

3:50 rear end, flat top pistons, will be running 4v long tube headers, and duplicating size and configuration of "boss 351" exhaust system, and FMX trans. Remember, I'm trying to build a "Boss" clone, so kind of have to have 4v heads. I understand the limitations I will encounter using stock valve train, but I believe I can build a modestly fun car for my budget right now. Thanks gentlemen!!!

 

[c9zx]

Are you wanting to leave the short block intact or completely disassemble the engine? Have you verified the pistons are flat tops with just eyebrows? Chuck

 

[Omie01]

WOW! Ok, must admit I was wrong, I assumed being a 72 block they would have rebuilt with flat top pistons, but they didn't. They are dished! This block was built by Tampa Engine Labs of Florida. For some reason the block is bored .060 over!!! Is this going to be a problem??? Now I have to build with lower compression, and thin cylinder walls so I guess stock 4v is as good as its going to get for this motor. Also 4 of my rocker fulcrums had .020 shims under them, which leads me to ask, how do I verify if I need to put shims under the new rockers? Some of the little splash shields above the pushrods were missing, where can I get new ones? Looks like I have some studying to do!!!:s


PS, I want to leave the crank and pistons in the block.

 

[c9zx]

WOW! Ok, must admit I was wrong, I assumed being a 72 block they would have rebuilt with flat top pistons, but they didn't. They are dished! This block was built by Tampa Engine Labs of Florida. For some reason the block is bored .060 over!!! Is this going to be a problem??? Now I have to build with lower compression, and thin cylinder walls so I guess stock 4v is as good as its going to get for this motor. Also 4 of my rocker fulcrums had .020 shims under them, which leads me to ask, how do I verify if I need to put shims under the new rockers? Some of the little splash shields above the pushrods were missing, where can I get new ones? Looks like I have some studying to do!!!:s


PS, I want to leave the crank and pistons in the block.

With the open chamber 4V heads the CR should be about 8.02:1. It is a roll of the dice about .060 over being a problem. If the core shift is less than what is common you may be OK. If not, it could be a problem. The .020 shims may be there to compensate for the valve seats being cut deeper on those cylinders. If the new heads are done properly, uniform seat depth, you shouldn't need the shims. The oil deflectors are still available from Pioneer, PN PF-524. Studying is not a bad thing when it comes to any technical topic.

At 8 to 1 keep the durations and overlap small, with reasonable lift numbers.

Chuck

EDIT: http://reviews.birdeye.com/engine-lab-of-tampa-inc-545077408

Read the 5 star reviews. Very disturbing. I would say put it back together without upgrading. Save for a proper build and drive the car. Just my opinion.

 

[barnett468]

WOW! Ok, must admit I was wrong, I assumed being a 72 block they would have rebuilt with flat top pistons, but they didn't. They are dished! This block was built by Tampa Engine Labs of Florida. For some reason the block is bored .060 over!!! Is this going to be a problem??? Now I have to build with lower compression, and thin cylinder walls so I guess stock 4v is as good as its going to get for this motor. Also 4 of my rocker fulcrums had .020 shims under them, which leads me to ask, how do I verify if I need to put shims under the new rockers? Some of the little splash shields above the pushrods were missing, where can I get new ones? Looks like I have some studying to do!!!:s


PS, I want to leave the crank and pistons in the block.

you can run .020' thick cometic head gaskets with the same id as the bore, then mill your heads for the rest of the compression increase . . easy deal.

get a 3 row 24" high efficiency rad.

high flow pump

get the water bypass plate

180 or 185 non cleveland thermostat

run one of the 268 cams or the next step down xe262h

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=847&sb=0

.

 

[Omie01]

I was just looking at the xe262 cam today, I think that might be the way I go. And just get all the matching components from comp cams. Thank for the help, on a side note, I might have found a full cleveland a guy is willing to just give me if I go get it!! Then I can start a slow build after I get the car put together!!

 

[barnett468]

I was just looking at the xe262 cam today, I think that might be the way I go. And just get all the matching components from comp cams. Thank for the help, on a side note, I might have found a full cleveland a guy is willing to just give me if I go get it!! Then I can start a slow build after I get the car put together!!

yeah the dual pattern will work a bit better than a single one with those heads and it will be quite snappy off the bottom and pull decent to around 5k but i would definitely get the compression up or you won't be happy.

what intake are you using?

yeah, never turn down a free clevo.

don't buy comp lifters, use crane anti pump ones or any others.

.

 

[Mustang Dynasty]

3:50 rear end, flat top pistons, will be running 4v long tube headers, and duplicating size and configuration of "boss 351" exhaust system, and FMX trans. Remember, I'm trying to build a "Boss" clone, so kind of have to have 4v heads. I understand the limitations I will encounter using stock valve train, but I believe I can build a modestly fun car for my budget right now. Thanks gentlemen!!!

Good choice. If mine was originally an FMX, would have went that way as having bad legs but. ::beer::::beer::::beer::Other than the FMX tranny and still with 2 1/4" pipes from the 3" hooker headers, about the same set up as mine. If I ever do get the AC and brake job taken care of, will look at the 3" pipes from the headers to x pipe and into pair of flowmaster 10's. from there don;'t matter, will stay the same. Enough toasts for me.Mikke

3:50 rear end, flat top pistons, will be running 4v long tube headers, and duplicating size and configuration of "boss 351" exhaust system, and FMX trans. Remember, I'm trying to build a "Boss" clone, so kind of have to have 4v heads. I understand the limitations I will encounter using stock valve train, but I believe I can build a modestly fun car for my budget right now. Thanks gentlemen!!!

Good choice. If mine was originally an FMX, would have went that way as having bad legs but. ::beer::::beer::::beer::Other than the FMX tranny and still with 2 1/4" pipes from the 3" hooker headers, about the same set up as mine. If I ever do get the AC and brake job taken care of, will look at the 3" pipes from the headers to x pipe and into pair of flowmaster 10's. from there don;'t matter, will stay the same. Enough toasts for me.Mikke

re: my under carriage. Canton 7 qt extra wide/shallow oil pan with pick up baffles, of course baffles in the engine covers, gear vendors overdrive below the toploader and H pipe and through flowmaster 40s down to Mach 1 chrome tips.