1974 390 Camshaft

[FoMoCo1]

I'm one of the older (1960's) FE engine guys and I have acquired a 1974 390 "mirror" 105 engine that was in an old U-Haul truck. Does anyone know if Ford retarded the 390 cam grinds 4 degrees like they did in the later 360's and other engines?

[fastEdsel]

That is a really good question. My son and I just repaired a flat cam in an International Harvester 345 V8. My son, a parts man by trade, located a new cam for this engine from Comp Cams. It fit right in and has a little more duration on the intake side to let slightly more air in for higher compression and does it ever work nice. We also replaced the hydraulic lifters. My advice is to get all the info, casting numbers etc you can from your engine and call Comp Cams, they are on the net and are very helpful. We also did a FE 390 and had an RV cam installed and it seems fine, good tone, and excellent performance, 600 Holley 4 barrel, #53 primary jets, 18 MPG. It dynode 325 HP, 425 ft/lbs torque. Don't get crazy with the pistons and these engines will turn a lot of heads! Good luck with your project!

[hazelnut]

Got to ask the question : Are you sure that it's a FE and not a FT ? Ford made 389 FT engines just for U-haul

[FoMoCo1]

Got to ask the question : Are you sure that it's a FE and not a FT ? Ford made 389 FT engines just for U-haul

I don't believe so because it has the 3 bolt crank pulley and smaller snout. The block cast is D3TE but that of course was used for the 391 FT also.

[FoMoCo1]

That is a really good question. My son and I just repaired a flat cam in an International Harvester 345 V8. My son, a parts man by trade, located a new cam for this engine from Comp Cams. It fit right in and has a little more duration on the intake side to let slightly more air in for higher compression and does it ever work nice. We also replaced the hydraulic lifters. My advice is to get all the info, casting numbers etc you can from your engine and call Comp Cams, they are on the net and are very helpful. We also did a FE 390 and had an RV cam installed and it seems fine, good tone, and excellent performance, 600 Holley 4 barrel, #53 primary jets, 18 MPG. It dynode 325 HP, 425 ft/lbs torque. Don't get crazy with the pistons and these engines will turn a lot of heads! Good luck with your project!

I'll take you're advice and get in touch with Comp Cams and thank you! Do you recall what cam you installed in the 390?

[cpuchalski]

We also did a FE 390 and had an RV cam installed and it seems fine, good tone, and excellent performance, 600 Holley 4 barrel, #53 primary jets, 18 MPG. It dynode 325 HP, 425 ft/lbs torque.

Do you happen to recall which RV cam you used in the 390? My build has a Comp 268DEH, Holly 600 (not sure on jets) and Holly Street Dominator intake and I'd be thrilled to see mileage and torque specs like you mentioned.

I assume you're running headers and dual exhausts?

Thanks,
Corey

[fastEdsel]

I will try to track down the cam we installed in the FE390 and report back. I know it was sold to me as an RV cam but I think it could also be used in the Ford GT390 applications and perhaps some 410 and 428 engines, all I know for sure it has given the engine a very subtle rumble which I am happy to report a very good performance. Due to limited space I could not run headers so the factory cast iron manifolds were reinstalled, connected to 2" inlets on dual stainless Flow Master mufflers, 1 7/8" tail pipes out the back, full length. Remember that the 390 is still putting out 180 cubes of exhaust per side so big pipes are just more expense for your project and this combination more than handles all the wind off the 390. I went stainless Flow Master's because of my "unusual cruising habits" I have blown apart 2 sets of so called "stock mufflers" in 21,000 miles since the rebuild! I am plenty happy with this engine but if I change anything on it I would switch out the old cast iron intake and install an aluminum one because they are much more efficient and because I can. I also should report that it has a Pertonix ignition set at 9" advance. Done up right these engines will continue to surprise a lot of folks. I have owned Ford trucks with 352's, older 360's which went like crazy and newer 360's which were complete dogs but they too with cams changed, planed heads and different pistons ran just long enough to get me to the closest GM dealer and trade them off before they started smoking like a warming up 400 Cummins diesel. I also know there are folks on this forum that have waaaay more experience with FE engines than I do, this combination worked for me, I will help where I can.

[My427stang]

That's a good question on cam retard. The answer is yes, sort of, but NOT like the later 335 and 385 series.

Ford used a few different cams in the 360/390 over the years and they were all wide lobe separation and late intake centerline. However, no stock timing set did it on an FE, period, not even the later 360s, it was in the cam grind itself, and generally it was somewhere close to a 112-114.5 intake centerline, which is really late by today's standards, but it did allow them to get a little RPM out of a cam that was incredibly smooth. Additionally, late cam timing sort of acts like an internal EGR, I am not sure cared about it then, but 2000+ Mopars did the same technique

So likely advancing the stock cam using an aftermarket multi-position lower gear will drive vacuum, torque and drivability way up, and with the short lift and well advanced intake lobe right not, you should check, but I'd be amazed if you had any intake valve clearance issues even if you advanced it 8 degrees.

Just remember though, to make an FE run well

1 - Recurve the distributor
2 - Headers and good duals, preferably some style crossover and err to the large size, not small, intermediate and tail pipes do not affect torque. 2.5 is a good safe bet, but on a very wimpy build 2.25 will do OK
3 - Gears, intake and carb to match use
4 - Then go inside if you need more.

I will add, recurving is always good for part throttle drivability in a 70s Ford, but there is no reason to put any money in an FE without some sort of headers and exhaust, it is THE biggest gain, and must be done to support anything else you do.

While on a soapbox LOL also, when looking at heads, realize FE heads have different exhaust port locations (high or low), you need to match headers and gaskets to the heads you use, and many "experts" overlook it. If you do, you will likely blow out header gaskets if you have a mismatch

[FoMoCo1]

That's a good question on cam retard. The answer is yes, sort of, but NOT like the later 335 and 385 series.

Ford used a few different cams in the 360/390 over the years and they were all wide lobe separation and late intake centerline. However, no stock timing set did it on an FE, period, not even the later 360s, it was in the cam grind itself, and generally it was somewhere close to a 112-114.5 intake centerline, which is really late by today's standards, but it did allow them to get a little RPM out of a cam that was incredibly smooth. Additionally, late cam timing sort of acts like an internal EGR, I am not sure cared about it then, but 2000+ Mopars did the same technique

So likely advancing the stock cam using an aftermarket multi-position lower gear will drive vacuum, torque and drivability way up, and with the short lift and well advanced intake lobe right not, you should check, but I'd be amazed if you had any intake valve clearance issues even if you advanced it 8 degrees.

Just remember though, to make an FE run well

1 - Recurve the distributor
2 - Headers and good duals, preferably some style crossover and err to the large size, not small, intermediate and tail pipes do not affect torque. 2.5 is a good safe bet, but on a very wimpy build 2.25 will do OK
3 - Gears, intake and carb to match use
4 - Then go inside if you need more.

I will add, recurving is always good for part throttle drivability in a 70s Ford, but there is no reason to put any money in an FE without some sort of headers and exhaust, it is THE biggest gain, and must be done to support anything else you do.

While on a soapbox LOL also, when looking at heads, realize FE heads have different exhaust port locations (high or low), you need to match headers and gaskets to the heads you use, and many "experts" overlook it. If you do, you will likely blow out header gaskets if you have a mismatch

Yes, I've built FE engines from the 60's era and I agree 100% about the iron log exhaust manifold, they don't flow all that great. I've never had a later 390 like this '74 however I've heard several times that Ford did not use cams that were altered in their 390 truck engines like they did in the 360's and other emission engines but I've never had a degree wheel on one. I do know its the mirror 105 block and has C8 heads on it. BTW- Great post you did there.