How do you guys with the 250 like the 274 cam?

69stang_250

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So I have finally gotten around to pulling the engine out of my mustang and after pulling the head I see that it needs some TLC. I am going to rebuild her and have a few questions for you guys with 250s.

1. How does is the 274 cam working out for those that have it?
2. I was going to get an aluminum head a while back but I'm not sure my budget will fit it in; however, I'm not sure how much the machine work will be just yet for the head I have (69 250) how much have you guys spent rebuilding the head, bigger valves, 2v conversion, seats, and the exhaust devider?
3. What Pistons would be the best for this build? ( will be a weekend and some times during the week driver)
4. Have any of you pulled one of these engines apart and found some kind of metallic curd on the Pistons and on the chambers of the head? ( this is the reason I ask about Pistons)
5. Have any of you guys had any issues with duel exh. And starter clearance with the 250?

Those are all that I can think of right now, but I am sure I will have more. Also, to clear this up. I grew up in old muscle cars so a rough idle does not worry me at all. The car has a 3.03 and 3.00 gear right now. This stuff will be changed a little down the road, but for now I am working on the engine so once the car is back form the body shop I can get her put back together and have some fun.

One more question. How much have you guys paid for a performance build?

Thanks guys and gals.
 
paid $1800 in West. MA (suburban/rural). Is for a bronco so can't say on a 274 cam (when I pick up the pieces to the puzzle in a wk or 2 it'll have the Comp 260).
Better get the alu head now (no matter yer budget if serious), I doubt any will B around shortly.
Starter clearence - I got a late 80s/90s V6 'stang for my '69 250. It will clear any headers out there.
Keep postin as U go...
 
as it's in a bronk - I wanna lill (low rev high) tq monster for off rd (30% on/70% off rd).
:eek:
not sure this build will achieve that. It's 170ci wrked "OK" for almost 30 yrs.

seek 9 - 9.2:1 compression
RBS carb (215 cmf 1V)
3 ang. valve job
back cut ex/int valves
advance cam by offset key
sm head port by machine ('port averaging') - is a '79 250 head
254 ci boar result,
decked block
260 Comp cam (440 lift, 110 LC)
machined to avoid umbrella VS
Molly 1st rings
regrind crank (? Moio Roio ?) not sure of his handwriting here
There seems to B some other minor things done at the shop. I'll try'n get details when I p/u in a wk or 2.

I wished to use the 300/4.9 for this project but I've been running this lill bobtail since '87 and have never had the money for that goal. This one will B stretchin me as it is. The application is (as stated above) a "wrk truck" if U can call an SUV that. It skids logs up to a neighbor's band saw mill in my swampy/hilly neighborhood. Serves as a back up vehicle (off site employment commuter) when an '01 Focus wagon breaks down. Takes a trailer full of sometimes green lumber to home building sites that have no 'official driveway' (often backing in a good distance) sometimes 30 mi away, on 2 lanes and I 95. If able (1 reason 4 the SBF bell) I'd like another gear on top/bottom of my oem 3.03 (3 speed top loader) installing a 1 inch BL to ease swap in of an NV3550. Not the nice low 6:1 I'd like but 4:1 low and a overdrive 5th gear. Other dreams - rework the frnt of the motor to add 2 accessories. I have a sno plow pump (the rig was an income producer there as well) to add and the alternator can B a hi amp Porta Power mig welder. Lastly there's a York ac compressor that can fill an air tank for pneumatic tools. The PTO needs a rig built for an auger I have planned. As it has 3 tops (rag, wagon, p/u) I'd like to place tool boxes on the rails. It's a heavy machine, will need to take it to the town dump to get on the scales at some point.

The vehicle has it's full fenders, no flairs, original seats interior/exterior, etc (see sig below for additions).
- What's ur goal? -
 
@69stang_250,

1. Absolutely love the 274 cam now. It always pulled strongly for me, but with the DUI it idled quite roughly (although it never stalled once warmed up) - with the MSD 6 AL it idles much better.

Have the 274/274/108 in my 250 - '62 Ranchero. My goal was to build the strongest, most durable N/A 250 that could run on pump gas. The 250 makes the most of the cam with higher compression than stock (about 9.3 SCR), the AL head, a Holley "500 CFM" 2 BBL, custom curved DS2 with MSD 6 AL, CI headers, true duals with an "X" crossover and Flow Masters, and a stall speed converter. The engine is also durably built with forged pistons, ARP main studs, ARP rod bolts, rotating assembly statically and dynamically balanced.

3. Out of the box, the 250 has about .100 deck height, which is bad for squish and encourages detonation. I used early 300 rods and custom RaceTek (formerly JE) pistons to raise the pistons and achieve .005 deck height. If your budget allows this might be a good option for you. I think the cost for pistons and rods, including minor rod work and ARP rod bolts, was about $1K.

5. In my Falcon Ranchero, the headers, starter, auto trans cooler lines, and starter cable from starter relay all tried to occupy the same space. :) I resolved this by rerouting the trans cooler lines on the driver's side and by using a PowerMaster mini-starter. The pivot joints on the CI headers also helped with fitment quite a bit. However, if I remember correctly your later Mustang has quite a bit more engine compartment room than my early Falcon.

With the AL head, intake, and Holley 2 BBL, and including the TCI stall speed converter, my engine build was probably $5K (I did all the assembly myself). Certainly if you include the cost of the DUI that eventually failed and was replaced with the DS2.

Thanks
Bob
 
Can't comment on the cam, but I can say I'm very happy with the other work I did on my 250. See the thread, 250 "Freshen up" for all the details.
 
Thanks for the input on your engines.
This engine will be going right back in the mustang once it comes back from the body shop. I am trying to stay below $4,000 on the engine build, this is why I asked about the head and how much you guys and gals have spent on your builds. Thinking about how much it will cost to improve the head I currently have, I think the AL head will only be a couple hundred more than the mods I would be doing. As far as the build goes, I will be doing it myself. I've never built one of these before but after rebuilding Aircraft engines for the past 10 years it can't be that much different or difficult.
I will start a new thread and ask y'all a couple more questions, along with posting some pics up of the tear down and build up. Thanks y'all.
 
"...that much different..."
@ assembly ck back - every one has anomalies & there's 3 or 4 here as well.
 
Well I say that because of the general mechanic practice. I am aware that each engine has special things you should go the extra mile to do just to ensure extra oil flow, prevent oil leaks, and things of that nature. but when it comes to critical measurements, such as the bores, crank journals, and such, procedure I am sure is about the same. I have read up on some of the issues people on here have had with their builds, and have made plenty of notes so I don't make the same mistakes. I hope none of this comes off being cocky, if so, that is not my intention. I am very humble when given advise and take any I can get, but I am very confidant in my mechanic abilities :)
 
"... engines for the past 10 years…"
"...confidant in my mechanic abilities …"

I wish I hadem!
 
It's just all in practicing. I was lucky my dad was one of two mechanics in the town I grew up in and I got a lot of exposure to engine building and other stuff at a very young age. Joining the military and working on helicopters just made me better at documenting the work I do....... And it made me start triple and quadruple check my work lol! Them things can't just pull over to the curb if they brake lol!
 
But they are super fun to work on. Get tare into the engines and rotor systems pretty regularly to inspect them, all depending on the air craft. And you get to see where the auto industry gets their futur tech from lol
 
:beer: For sure I went to school and got my A&P licenses after High School I tried to get transferred to Choppers when I was in the Army. :nod:
 
That license opens up a lot more doors than I thought it would. I was a UH60 Blackhawk mech/CE while I was in, but I cross trained on every air frame other than fixed wing and MD500s. Then worked down in the gulf on EC145/BK117, now it's school full time lol I miss the hands on stuff some kinda bad! What did you do in the army if ya don't mind me askin? I always enjoy talking with prior service.
 
All my A&P training was on really old fixed wing stuff didn't get into choppers at all except for book training looking at a couple that they brought to the school. The Army was also a long time ago was active duty in 1970 to 72 (during the Vietnam era) was stationed over in Germany. Infantry (11C) a 4.2 mortar gunner, also drove an APC, Jeep, a 5 quarter (Jeep pickup) and once in awhile a Duce and 1/2 (2 1/2 ton truck). Called up to Help train a Nation Guard unit on the 4.2 during mid 70's then inactive until 77.
 
My moms husband was in Germany at the same time. He was a chap assist. I just joined up with the VFW here in the area and have been talking with a lot of guys that were in the older wars. I just got off active duty last April.
 
Excellent glad to hear that the VFW is great haven't been to one since I moved out Ca. am hoping soon to get signed up again with one in this area. Take care and good luck on that 250 build they are great engines. :nod:
 
Thanks. I just sent Does10s an email and going to pick up one of the bare AL heads and intakes. I'll be posting pics and stuff on the "250 build" thread. Think I have a pretty good idea of what components I am going to throw together.
 
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