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Discussion Starter · #1 · (Edited)
ok, did a head cam and intake swap on a 351 roller engine, speed density. ive got a maf conversion ive ran years ago but didn't want to run it due to losing my cruise and 4 low...........anyway, ive ran the heads and intake with the stock cam before with no issues on s.d. so got a custom ground cam from cam research thinking it would even compliment the parts that much more. i told them what i was putting it in and that i wanted torque for pulling/offroading/etc........told him my list of parts i had etc.....typical cam grind questions, and told him that its speed density......yati yati yata....

after several heat cycles and checking for leaks, adj. timing etc.......set out for a test run.......throttle response is better under 2k but after that its like no more power? its worse than the stock cam........am i missing something?

no check engine light until i start to drive, after a hundred yards or so check engine light comes on but tells me its the purge valve solenoid and i think low battery voltage.

am i missing something here? could i still be a tooth off on the distributor? or my flywheel pointer bent or something thats throwing me off? ive set timing with the spout out, 3 times to veryify 10 deg, then plugged spout back in. cam was installed dot to dot like i was instructed by the company, no need to degree it. ive removed valve covers and checked valve lash cold and warm, air leaks, tps, all those sort of things.........just want to make sure im not missing something before i call the cam company.
these are the cam specs;
.480/.480
272/280
duration at .050 in 208, ex 213
112 deg lobe seperation
was ground for ported gt40's with larger valves, 1.72's, edelbrock upper/lower, big bore tb, shorty headers, speed density friendly.......
 

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Discussion Starter · #2 ·
as a follow up, if i advance base timing about 30 deg advance, helps it out the most.
i did by an aftermarket balancer to replace the original one, which the 0 seemed to line up with the pointer when the number one was at tdc when the head was off. could the timing marks be off on the balancer? something isn't right.
 

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'92 Custom w/ '95 MAF 5.0 M/T, 33's, 4.10 LSD
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My barely educated guess is you need to degree the cam and make sure everything is lined up properly. Having just started reading up on that topic, it's probably 50/50 whether your setup is retarded (that sounds bad!) by following the dot-to-dot method.

The fact that it's running better by advancing timing that far somewhat supports the theory.
 

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Discussion Starter · #4 ·
it starts right up but dies when you put it in gear or come to a stop
the power loss is all over the whole rpm band
i installed the cam dot to dot which i asked the guys at the cam shop if i need to degree it when installing it and was told no, everything will be taken care of so all i'll have to do is dot to dot. my luck its off lol.....because im at a loss.

vacuum has lowered slightly from 20 with the stock cam to about 17.5 now
i can remove spout, set it to 10 deg, put spout back in and does nothing for power or when putting it in gear.
 

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From the Picking a cam Tech Thread
For a good fuel injection truck cam:
intake duration @ 0.50" should be kept at or under 210
Gross valve lift should be kept under 0.500
Lobe seperation should be at or above 114°


If you find everything else looks correct, that Lobe Seperation ## may create issues with the speed density system. They are very picky to vacuum and/or manifold pressure changes. Which you have also seen.
 
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85 Bronco, 309ci I6 w/4bbl, np435, 4" lift, 37" Irok NDs, 4.56 w/ Detroit Locker and tru trac
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I only know of one guy able to run a 112LSA cam in a SD SBF. It really should be 114° LSA. The other specs look good.

What would you loose cruise and 4 low with a MAF swap??
 

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Discussion Starter · #7 ·
well i guess cam research was a waste of money.
so its either swap cams or put my maf back on.
my maf kit was purchased online and came with an a9p which don't have those functions of 4 low map, or cruise control, my baumanator tranny controller can get two maps but its just more work.
i wonder why they told me this would work for speed density? they are suppose to be the ford cam/engine building gurus and won several awards and contest, even the amsoil engine masters challange twice...........guess they don't know about stock speed density....lol

they originaly wanted me to run 110 deg lobe seperation until i told them im speed density, then they said the 112 will work but recommended 110 along with maf.
 

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'92 Custom w/ '95 MAF 5.0 M/T, 33's, 4.10 LSD
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i installed the cam dot to dot which i asked the guys at the cam shop if i need to degree it when installing it and was told no, everything will be taken care of so all i'll have to do is dot to dot.
My point was, them saying it doesn't make it so. They can limit the likelihood of dot-to-dot being inaccurate with a precision grind, but there are still alignment elements outside their control. I didn't order a cam degreeing kit at first, thinking I could get by with dot-to-dot, but reading up on it convinced me there's just no way of knowing if you got it right otherwise, until the performance is a disappointment.
 

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After you plug the spout connector in are you seeing the timing advance with increase in throttle at all? Perhaps the dizzy isnt advancing the timing properly. perhaps your needing more fuel? just throwing things out there.

i am also surprised about the 112 lob separation.
 

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The speed density setup in a FOX mustang, which I am sure they are more familair with, maybe more able to deal with the changes then what is in the trucks. This I do not know for sure.
The stock Mustang cam is also likely a bit more then the stock truck, therefore the cam you have now, maybe within what the Speed Density mustang ecm can handle, just not the truck....

I agree would be worth checking out the dizzy and making sure all the fuel side is in good shape. A Wideband would really help you see what is currently going on too.

EDIT: I had another though to verify the cam firing order matches how you put the plug wires on too.
 
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Discussion Starter · #11 ·
i took several videos to show you guys how it runs, i really don't know a difference from stockish engine to this one.

and i SHOULDN'T say there is less power but I don't notice any more than it was when it was stock, honestly.

the dizzy may not be working right, with the SPOUT IN, if I adjust timing i can see the timing change on the flywheel. im not sure if its suppose to do that. i did try setting it to 13 and made a test run and in pings at WOT like it did when it was stock.

the only REAL problem is has is dieing at idle or when you are coming to a stop sign. all else seems to be on par besides its running hotter than it should.

yes fodder, i should have degreed the cam, i have everything here to degree it, ive used it to practice on my other 351 on my stand to get stock truck cam specs. but i didn't, i did the swap in the truck and didn't want to be bent over that long, i had to sit on the top of the block with everything off to get the timing cover off and put the cam/timing set in and BTW you can swap a cam in w/o having to take the a/c condenser out.
 

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Discussion Starter · #13 ·
yes, radiator out and remove the bolt attached to the cam once you get it almost all the way out.

also a good tip, i use the big laundry detergent jugs with the spout as parts washers on its side with a large hole cut in it as a lid. i go to the store and get my 6 gallon gas cans full of e85 as parts washer fluid. and for big jobs, i put the e85 in my pump up sprayer as a portable parts washer, just don't leave the pump submerged in fluid when not using, makes a great degreaser for pretty cheap. i'll post pics of my setup
 

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Of course the only vids it loads are the not the ones I wanted. I'm thinking of moving the map sensor to a different spot closer to the manifold, question is, does it need to remain in its original position?
Parts buggy
171485

Here's the parts washer
171483
171484
 

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If you get a Bronco/F-series [MAF] PCM, you wouldn't need the MAP sensor at all. It's only used on the Mustang PCMs. Took me a while to find the source of that inconsistency in the MAF swap documentation.
 

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Discussion Starter · #17 · (Edited)
i didn't know that, what i do know is that you have to unplug the vacuum line going to it to change it from a MAP to a BAP sensor with my swap.

my kit "stupid overpriced" from massair.com
it came with a 76mm maf calibrated to 24# injectors, a9p, baumanator tranny controller, wiring, twin hego's and some horrible instructions.

ive always wanted to find an obd1 maf computer, ive been told there were very few and are hard to find. ive only seen pictures of them a few times, one was even supposedly a 93 model, a few 94 and some 95 cali models i think only. i found one at a local junkyard that was 95 maf but it was a 2 wheel drive. it also had a different harness to the tranny with an extra connection that mine doesn't have.

i read one article last night of a guy running a similar cam in his SD and he said he had to move the map sensor from the vacuum tree to its own spot closer to the intake manifold to get it to operate correctly.
 

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Discussion Starter · #18 · (Edited)
omg i thought i fixed it............lol
i moved my map sensor with a small hose right next to the vacuum tree as a test, truck starts right up as usual, i let it warm up until idle goes down and put it in gear and IT DOESN'T DIE..........so i go back and forth trying to kill it by putting it in gear and it never did.........but my dreams were shattered after a short test ride, as I came to a stop.....she died.

so im either going to have to put that maf kit back on (don't want to) or put the stock/other cam in it. i wanted to go back to sd just due to the fact of getting replacement parts is a lot cheaper and more abundant than the aftermarket stuff.

what did yall think of the vids? there was no extra power over stock, to me feels like a loss slightly in torque/power over stock cam and junky e7's
oh and "da river rat" "superjet701" and "jetski247" are now one......lol
 

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Have you gotten any further with your diagnosis?

I still don't understand why you lose 4low and cruise control doing a mass air conversion.

As for the truck computer you found being in a 2wd truck, that doesn't matter.

hth
tim
 

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Discussion Starter · #20 ·
ive switched it to mass air since this:
but could not keep it from dieing when putting it in gear or coming to a stop on SD, all other aspecs of the cam with the SD seemed ok but no more power than stock.

im running an a9p mustang computer, mustangs did not come with cruise control or 4x4.
although the 4x4 works no matter what computer; except for the dual maps for shifting, there needs to be two maps, one for 4 hi and one for 4 low. so a two wheel drive maf computer that controlled an e4od wont have a 4 low map, so shifting will have to be manual or it shifts very wierd with a lot of u joint snapping force.

since my maf conversion has a baumanator, it does have a function for two maps and the ability to select between the two. its just a bunch of wiring.
 
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