1969 block 351w EFI upgrade

[NM_outdoors]

I'm in the process of a frame-off on my '70. I've owned this dude for 27+ years and put a 351w in it about 25 years ago. Ran a 2V on it ever since but am now planning to modernize with, among other things, EFI. I've aquired a few parts including the stock truck lower and am planning to adapt to a 5.0 upper and use mustang MAF. One recent snag was finding out the 351w block I have is a '69 (C90XXXX) and therefore has the .023" shorter deck height. I'm okay with fitting/machining the EFI truck lower intake as needed but I plan to freshen the lower end and possibly put some GT40 explorer heads on it too. After reading several threads on here re: the 69-70 blocks, I'm wondering if getting parts for a mild build will be more difficult than I expected? This engine ran well and didn't burn/leak any oil when I pulled it out for the bronco resto. It was my daily driver for half the time ive owned it but doesnt have alot of miles on it (<100k?). I'll know more about its current condition when I get time to pull the heads/pan (sometime within the next couple of weeks but I just wanted to get a few opinions before I get too deep into a rebuild. Thanks

 

[airbur]

You might consider looking for a later model block. I found a 1994 roller 351w for $200 locally.

 

[needabronco]

EFI is simply an intake swap! I know plenty of folks running efi on older late 60's to 70's 351's with absolutely no issues.

 

[airbur]

Sounds like he is doing much more than EFI.

 

[needabronco]

Like a head swap? No biggie either! Other than maybe a half a compression point...

 

[NM_outdoors]

Thanks for the input guys. I know a "roller" is a more preferred route but I'm also hearing that these older blocks are a thicker/stronger/alloyed casting. For what I'm doing (more tractor than race car), I don't feel the need for a roller block. I'm not sure how much is typically taken off when decked for a rebuild, but it seems like even a newer block (that has been decked) could be in a similar situation? When I picked this engine up years ago, it was a long block with original (just honed) bore so I'm thinking it probably is still at original deck height....... Based on how it ran when I pulled it, I don't foresee having to replace much in the lower end.

 

[70_Steve]

I'm not sure how much is typically taken off when decked for a rebuild, but it seems like even a newer block (that has been decked) could be in a similar situation?

The block may not be decked at all during a normal rebuild.

But, interestingly enough, I had my 86 351 block decked .023 or so intentionally. I wanted to bump up the stock 8.5-1 compression to around 9.0-1 but couldn't find off-the-shelf pistons to do that. My choices seemed to be either stock, or pistons yielding 10.0-1 and greater...

So, after playing with a couple compression ratio calculators, I decided to go with the stock 8.5-1 pistons but reduce the installed height from .028 to .005 (should that be -.028 to -.005?) by decking the block. With my E6 heads, with the huge 69CC combustion chamber, this gives me a 8.9/9.0-1 compression ratio while reducing quench height to .044.

 

[Timmy390]

The block may not be decked at all during a normal rebuild.

Ditto. If the surface is good and the block is square there isn't a need to do anything other than a cleaning.

I had the deck on my 390FE dropped it "0" and run a thin head gasket to get my compression up to 10-1. the Ebrock FE heads have huge 72cc chambers.....

Tim

 

[KyleQ]

The strength is moot point, you are not building a 700hp motor. You want the later roller blocks so you can run any Mustang cam and the factory roller truck cams are one of the best low end torque cams you can get in a stock motor.

I had a 69' block I was going to build a 427 out of- the stupid low deck height made it much more expensive and was just a general PITA.

F4 block, GT40 heads, Mustang injection and you are set- its a great combo for street or trail....

 

[NM_outdoors]

Great feedback. I guess I'll be able to make a final decision once I find out how much needs to be done for a stock rebuild. I'm hoping the rumored "higher nickle content" provides wear resistance and no machining will be required?!?

 

[KyleQ]

Great feedback. I guess I'll be able to make a final decision once I find out how much needs to be done for a stock rebuild. I'm hoping the rumored "higher nickle content" provides wear resistance and no machining will be required?!?

Here is my junkyard/craigslist special F4TE 351W that sat without heads on it outside and got rained on motor $100 motor.


180+K on it and factory cross hatching still going- look how nasty that piston is!


Ahh - there we go Everything was re-usable, original pistons and all.


I had it checked and it only needed bearings and a .001 hone and that was it. EFI is a lot nicer on engine components compared to out of tune carb setups...

 

[Timmy390]

Here is my junkyard/craigslist special F4TE 351W that sat without heads on it outside and got rained on motor $100 motor.

You got to be one luck (fill in the blank)....LOL

No way in hell I could come out like that or I would already have a 351W in the truck. I can get any motor from the yard, $300 I pull and $350 they pull but I just can't take the gamble. I'm unlucky at cards and I haven't hit the lotto yet so chances are I would get a cracked block form the yard.........I'd end up buying 5 and still not have a running combo......

Tim

 

[KyleQ]

You got to be one luck (fill in the blank)....LOL

No way in hell I could come out like that or I would already have a 351W in the truck. I can get any motor from the yard, $300 I pull and $350 they pull but I just can't take the gamble. I'm unlucky at cards and I haven't hit the lotto yet so chances are I would get a cracked block form the yard.........I'd end up buying 5 and still not have a running combo......

Tim

What, your junkyards don't come with a warranty? Even u-pull up here will warranty a motor for x months/x miles.

Get on craigslist or your local racer/bullshit center and put out a want add. There is stuff everywhere, you just need to know where to look. The same guy gave me a beautiful chrome fuel rail with 8 EV6 style fuel injectors. I bought a $20 rebuild kit and took the apart and cleaned them. Freebie ;D

 

[jckkys]

Seems the only reason to pull the heads is to satisfy your curiosity. The early 351 heads have big valves and ports so GT40 heads won't do much, except giving you a 4.5cc larger combustion chamber. The cam is very close to the Explorer roller cam.
Just change your induction and leave the rest as a known commodity so you can evaluate the EFI set up knowing it's the only change.

 

[KyleQ]

Seems the only reason to pull the heads is to satisfy your curiosity. The early 351 heads have big valves and ports so GT40 heads won't do much, except giving you a 4.5cc larger combustion chamber. The cam is very close to the Explorer roller cam.
Just change your induction and leave the rest as a known commodity so you can evaluate the EFI set up knowing it's the only change.

True- I forgot how decent those heads actually were. If a guy wanted to, he could just toss an upper and lower intake on the motor, run a few wires and drive away...

 

[NM_outdoors]

Seems the only reason to pull the heads is to satisfy your curiosity. The early 351 heads have big valves and ports so GT40 heads won't do much, except giving you a 4.5cc larger combustion chamber. The cam is very close to the Explorer roller cam.
Just change your induction and leave the rest as a known commodity so you can evaluate the EFI set up knowing it's the only change.

Gotta admit, since I already have the complete engine on a stand, I want to take a closer look at 20+ years of my driving and maintenance. On the other hand, I do like the idea of minimizing the changes to assess the EFI install. Hmmmmmm….

 

[rguest3]

Roller Block or not does not really matter. The EFI system does not know the difference. The main concern is a computer friendly Cam. (Most Non-Roller Cams are not)

Call up Comp Cams, tell them what you are doing and have then suggest a Hydraulic Cam for current block, or have your block set up for roller lifters and put a Roller Retro Cam in it.

Comp Cams will get it right for you the first time.

 

[70_Steve]

Call up Comp Cams, tell them what you are doing and have then suggest a Hydraulic Cam for current block, or have your block set up for roller lifters and put a Roller Retro Cam in it.

Comp Cams will get it right for you the first time.

That's what I did, except I filled out their on-line form. I'd been looking at their 4x4/RV cams in the on-line catalog. What they recommended was a couple cams that weren't in the on-line catalog. New cams (at the time) with grinds specific for EFI.