further upgrades that will play nice with speed density?

[BerniniCaCO3]

I think I may have asked some of these questions before, but I wasn't serious about anything at the time and I've forgotten what advice I may have received.

On Tuesday the 24th I'm yanking my engine again. Why? 'Cause my oil pan is leaking from a crack, AND, my rightside header gasket is blown and my header bolts are mostly stripped out. Either one I might just do with the engine in the car, but with both of them, I might avoid some grey hairs by just biting the bullet and pulling the engine.
by the way, when I reado that header, what's the proper length header bolt, and should I use a lockwasher?

SO, while the engine is all out again, may be the best time if there are any last things I want to do to this engine.

What I have now is:

Mark vii speed density computer
stock HO block w/ forged connecting rods, flattish topped pistons
stock HO intakes
stock HO throttle body; modified to accept panther linkage
stock airbox
explorer camshaft
explorer gt40 heads
mustang shorty headers, h pipe, impala tailpipes for dual exhaust

timing is correct for stock spec. Plugs and wires are pretty new, and quality (iridium and silicone respectively), and and rotor are fresh, so those basics have always been good. Dunno what my fuel pressure is. Seems to be running rich usually, just on the basis of fuel economy/ slight fuel smell whenever I do an oil change.


I have lots of power 2500-3500rpm (in my highly inexpert and inexperienced opinion), but it seems to fall on its face and just not deliver past 4000rpm if I stab the go pedal.
Would a proper HO camshaft now be appropriate, with my 3.55 rear gears, now that I see 2000rpm+ consistently? (used to be I hung out at 1500rpm all the time).
Local guy has a ground billet camshaft for $150, stock HO specced, might actually be more precise than factory oem? (it's from CI cams?)
Also found these heads for sale locally, dunno if they're better than the gt40 heads I've got, or $300 better any way: http://baltimore.craigslist.org/pts/3086357317.html I'd have to buy rockers for them.
Finally, wondering about a proper gt40 intake rather than the HO.

I don't want to go too far, however, and seriously trip up my speed density system. I don't know at what point you need larger injectors (and I guess that would require a modded ecm to accommodate?). I don't know, if I put on an explorer throttle body, how to tell the ecm that it's now got a larger throttle body and to calculate for more airflow. I don't know if I put 1.7 roller rockers and a gt40 intake and tb and those windsor jr heads, if I'd lose the low end I've got? I don't want to build an engine that now has power at 4000-5000rpm, but none at 2000.


Final question on the side. If I put in an HO camshaft, I might as well toss the cheap ass chinese CAT lifters I bought a year ago. They're working fine now as far as I can see, but even out of the box you could tell there was more slop than oem lifters. What brands do you recommend for a quality build?

[BerniniCaCO3]

Well, main question for now, would an HO cam make sense now with my 3.55 gears?
Any talk of computers, harnesses, larger injectors, different heads, roller rockers, etc., now starts to talk about several hundred to 1000$ and gets into dreaming territory.

Better lifters an an HO cam?
Or keep the explorer cam?

[pantera77]

What valve springs are you running? I hope not the stock explorer ones.

I liked the HO cam that was in my 89 with 3.55's. It was advanced 4*, pulled decent up till 3K then it really kicked in to about 5200.

I'd certainly ditch the stock SEFI intakes for the gt40 style ones, along with the 65mm TB.
Don't forget to drill and tap for the IAT.
The SD question is really a toss up. I apparently owned the only decent running explorer motor (with an HO cam, 1.7rr's and a full 2.5" exhaust) on bone stock SD. What should be fine by SD standards, just doesn't seem to be the case with these cars. Everyone is different.

[1990LTD]

I was told that most of the stock lifters you can buy for our motors from parts stores etc are all from the same company. I don't know how much truth there is in that, it's just what I was told.


Were I in your position I would do the MAF swap. It's an upgrade that will play nice with everything in the future - and it can be tuned. Don't know if you have the D9S or DX3 computer so I don't know if you can tune your SD setup or not.

[BerniniCaCO3]

D9S. What is the difference?

[BerniniCaCO3]

I actually don't know. I bought my block and some other spare parts from a 'stang enthusiast, who had a box of new valve springs-- not in the original box, however, so they're mystery springs.
Is there a way to tell if my top end is limited by valve float (vs some other cause)?

[1990LTD]

One can be tuned and one can't. Yours can. I have the DX3 and can't.

[zoomie]

OK apparently i need to get serious and make a mondo HO tech thread, becuase people dont do enough research nor do they listen.
HO cam if you want more top end that expo cam is tqy but i wasnt impressed with it.
if you have a HO block with flat tops its an no go 86 block, might as well just use the stocker you have in your car.
keep the p heads the jrs are basically modified gt40 heads and you wont see much difference.
why use cheap lifters, as long as the stockers are good use them they will be fine.
i was going to use the stock expo ones only becuase they were newer and had bigger oiling holes.
for the tuneability factor, a stock fox Sd computer will work just fine
a very basic, but workable recipie that will net decent power

HO motor 87-90 88-89 were said to be the best years
Ho has 9:0:1 compression forged pistons

stock 5 slo has 8:5:1
expo intake tb and heads
ecm choices: d9s,a9p,a9l,DA1 i suspect the only difference between d9s and Da1 is the code....
do replace the timing chain,waterpump and whatnot while at it.
unless your going all out just use the gt40 stuff and port it ...carefully, there is a very nice drop in kit that works and is made specific to those heads as well as p heads.
put it together and have a ball.
oh MSD stuff yeah thatll help too like wires and cap it makes a difference....trust me

I have my own preferences for things, and i can suggest others, but my stuff works and works well.... or did before i had to get rid of my baby.

[zoomie]

One can be tuned and one can't. Yours can. I have the DX3 and can't.

anythign can be tuned, just need the right tuner.

[zoomie]

I actually don't know. I bought my block and some other spare parts from a 'stang enthusiast, who had a box of new valve springs-- not in the original box, however, so they're mystery springs.
Is there a way to tell if my top end is limited by valve float (vs some other cause)?

take the springs to a machine shop they can check they springs for you.

[zoomie]

one more thing unless its flat tappet cam stock lifters should be fine. if your worried clean them up and then stickem in oil until ready to use.

[Crownvicman289]

HO motor 87-90 88-89 were said to be the best years
Ho has 9:0:1 compression forged pistons

87-88 were the best years, SD supposedly had 10* more intake duration (advertised, not @ .050"). That buttplug of a 55mm MAF isn't helping anything on a stock motor. HO goes about 9.2 with GT40P heads FWIW.

My SD setup had a tip in hesitation that was largely cured by bumping fuel pressure from 39psi to 43psi, but it still had it in certain conditions. When I went to sea level, my WOT AFRs were much better and the tip in hesitation was gone. Yes it's true it learns itself stoich and applies said learning to the WOT curve as well, but it seems to me the DA1 over-leans for altitude. After it learned enough, the idle surge disappeared too.