"SteetMaster 390" intake manifold

[Alvin in AZ]

Final Results - First Great FE Intake Comparo

Recently bought a 390FE (C5AE-A 352 block) with a Streetmaster 390 intake manifold on it. :)
But since what I want is the highest amount of power+torque I can get below 3500 RPM... :)
I'd like to trade it for another 4 barrel intake manifold. :)

So a couple questions...
Do the aluminum intake manifolds tend to leak or cause other problems more than cast iron?
(because of aluminum's rate of thermal expansion is about twice as much as iron)

In your opinion, which intake manifolds should I keep and eye out for? :)

---------------------

It'll be for my '75 Dent with a T18 and the deal included a rusty, factory "T" two barrel intake
manifold. :)

Alvin in AZ

[dustman_stx]

Final Results - First Great FE Intake Comparo

Recently bought a 390FE (C5AE-A 352 block) with a Streetmaster 390 intake manifold on it.
But since what I want is the highest amount of power+torque I can get below 3500 RPM...
I'd like to trade it for another 4 barrel intake manifold.

So a couple questions...
Do the aluminum intake manifolds tend to leak or cause other problems more than cast iron?
(because of aluminum's rate of thermal expansion is about twice as much as iron)

In your opinion, which intake manifolds should I keep and eye out for?

---------------------

It'll be for my '75 Dent with a T18 and the deal included a rusty, factory "T" two barrel intake
manifold.

Alvin in AZ

I think you should stick with the Streetmaster. It produces good power. The only intake that you might see gains with would be the Performer RPM. Even if you did, I think they'd be minimal. I'm speaking from personal experience with running both on the same engine. The only difference I saw was a smoother idle to 2500 because of the dual plane design with the RPM. And this is a non-issue unless you are running an agressive cam.

[hotrodfeguy]

If this is truely what you are after "But since what I want is the highest amount of power+torque I can get below 3500 RPM... "

I would say SP2P or factory Iron 4V/GT/S-code and performer non RPM manifold. The SP2P has no benifits above 4k in any FE aplication. It is the worst manifold made for an FE over 4K. The others let go a bit higher around 5K-5500 and make more power 3500 and up.

[Alvin in AZ]

If this is truely what you are after
"But since what I want is the highest amount of power+torque I can get below 3500 RPM... :)"

-->{you betcha! :}
-->{sorta like a 300-i6 with two more cylinders;}
-->{I've got a T18 and "tall gears" figuring in the tires at 31.5" and 3.50:1}

I would say SP2P or factory Iron 4V/GT/S-code and performer non RPM manifold. The SP2P
has no benifits above 4k in any FE aplication. It is the worst manifold made for an FE over 4K.
The others let go a bit higher around 5K-5500 and make more power 3500 and up.

The SP2P is sounding good so far -if-... that "crummy" performance above 4k equates to
better-than-usual performance below 4k. :)

The little runners and small valves in the FT might be a little too much for a pickup but
I'm thinking along those lines, never said I was smart. :/ I really need to get off my lazy
butt and go get my 361FT and install it in my pickup temporary (if it'll fit) and try it out. :)

Alvin in AZ
ps- The 361FT is in Willcox AZ, about an hour away.

[Alvin in AZ]

Numbers for my 3.50 axle, 31.5" (235/85-16E's) and the T18 in 3rd gear (1.69)...

3500rpm = 55 mph, T18 3rd gear + 31.5" + 3.50 <---this is all the 360FE will do now and works ok. :)
4000rpm = 63 mph, T18 3rd gear + 31.5" + 3.50
4500rpm = 71 mph, T18 3rd gear + 31.5" + 3.50

I just expect the 390FE to get to 55mph quicker, that's all. ;)

Is my thinking kinda dumb tho?

Alvin in AZ
rpm x tire diameter / 336 x trans gear ratio x axle gear ratio= mph

[hotrodfeguy]

Between a 360 and a 390 they get the same milage, but the power is better with the 390.

[Dragon]

I used Streetmasters years ago and Torker 390s too both with smaller than Ford runners and both pulled from near off idle to 5200 with no loss of power. You don't go from 0 to 140 in a 68 F100 in 15 seconds if the manifold runners are holding you back above 3500. Both engines in my 68s were identical except for the intake one was a Streetmater and the other a torker. The torker went of the racer and the streetmaster on the street. Both did 140 and both played in the mojave desert and one played for 3 years in Baja.

[matt]

If you were looking for an intake in the lower rpms. and have the streetmaster to trade i have a three intakes toyou can coose from. I've been wanting to get a streetmaster for my mustang. I have a two factory 4bl. intakes one off a thunderbird and the other a galexie. Then a have a performer that i had in my truck.

[Dragon]

Factory intakes aren't well known for low end. Then depending on the years your factory intakes, especially the T-bird one will be a low riser. I have a C5AE low riser and low end does not come from that manifold. I have had to do more work to get my truck to take off smoothly with my 750 holley, and when I started writing this post it hit me all my street intakes until now have been medium risers or Streetmasters or Torkers. The Streetmaster and Torker intake has fantastic bottom end all the way to 5200 easy like I said above.

[Alvin in AZ]

Thanks for all the relies. :)
This is all new to me, never messed with cast-iron water-cooled engines before and
wanted my first to be an FE or at least a 300. :)

I can't see the graphs in this URL, are they still available somewhere?
http://www.network54.com/Forum/74182/th ... ke+Comparo

Not counting my chickens yet but kinda thinking the Edelbrock Performer (not RPM)
would be an "upgrade" for me and what I want to do?
The SP2P looks odd it's got such skinny runners. LOL :)
So a stock "T" cast iron intake wouldn't be any better than what I've got now?

BTW it came with the original four hole spacer that Jay Brown talks about so much. :)

----------------------------------

Loosened the rockers and all the valves are lined up straight as anything. :)
The seller thought the heads were messed up.
Should I next, mount a bell housing on it and do a compression check, or what? :)
#8 spark plug was so gunked up, it was bridged. LOL :) The rest are just black.

Alvin in AZ

[Dragon]

The comparo lost the pics and graphs because they were linked to a website that has been gone for over 2 years. The Streetmaster had real skinny runners but thin wall the Torker had larger runners at the carb base and street master size at the ports in the head.

A low riser manifold actually put the base of the carb about 1/2 inch above the point where they go and turn down to the valves. The medium riser has the inlets to the runners about an inch above the head entry points.

The original torker that I can't find anywhere even used for a 390 got put on my Baja racer. Both my 68s had identical engines. The cam a Crower Baja Torque Master, Headman Torque tube headers and EDC heads with 427 high riser valves, Cloyes roller chain and many tricks, oh and 7.75 forged pistons. From an 800 rpm idle both trucks would rip a house down at an idle. The Streetmaster truck if I towed anyone thought I had punched the throttle when all I did was let the clutch out at an idle. The torker would just build from idle to 5200 the more it revved the harder you got pushed back. The Streetmaster came on like I said at dead idle and jumped to peak torque close to 3000 rpm. The graph from the dyno went up at an idle to 1500 in 600 rpm to 359 ft lbs.

[hotrodfeguy]

If this is still what you are after " I want is the highest amount of power+torque I can get below 3500 RPM... ", I still stand by a dual plane intake and not a single plane. Pretty much all the numbers that Jay Brown did on the dyno were not under 3500. He did say that the SP2P had the most torque of all intakes under 4K. Thats the one I would go with for your original posting of under 3500 RPM. My S-code intake works great on my 390. It's what I went with, cause the SP2P intakes are going for a pretty penny. Last one I saw on E-bay went for over $200.

[george worley]

I have a S code on my 390 that's off of a 390 GT with a 1" four hole spacer. The spacer improves the torque quite a bit. Its heavy but it only cost me $25.00 and it pulls real good from idle to 4000 RPMs.

[Alvin in AZ]

Edelbrock Performer 390 intake manifold (P/N 2105)
(snipped from what Max wrote;)

The 2105, I figure, to be my best-bet, you suppose? :)

Are they going for less or about the same money as a Streetmaster 390? :)
I'm just looking for a straight across trade at some point.
Sounds like the SP2P would cost me more money. :/

Alvin in AZ
ps-
http://www.panix.com/~alvinj/file12/fe390crank.jpg
(stroke is for sure ~3+3/4" not 3+1/2" :)
http://www.panix.com/~alvinj/file12/fe390+55.jpg
(put a couple pieces of wood under it right after the pictures, ~foot x 1"x 2")
(haven't got a "store bought" engine stand yet ;)

[Dragon]

Well when I bought my new Streetmasters years ago I paid about $250 for them new.