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Good to know, I was just considering air flow, & not air temp, sounds like I probably do need to get the coned air filter back in a air box to get that temp back down. How did you go about getting a reading on the intake air temp ?
I'm using the OBDlink Bluetooth communicatior paired to a 7" tablet. It has a 1 time $10 Ford pcm software with it. You can go in and design your own gauge cluster, digital / analog, diagnostic and code resets us a bunch of other useful things. I have a gauge setup for towing that shows me trans temp, air intake temp, oil temp ac clutch on/off. Software connects to my home network and keeps firmware updated and emails data logs.
Curious on how much intake air temp affects your performance & how that might be measured?
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I'm going to be using the SOHC MAF, and would definitely think you would need to adjust the tune. I think not so much for the size, but for the airflow calibration in conjuction with the pcm... Those SOHC heads breathe differently, so the calibration for fuel/ air needs to be modified. I planned on a complete custom tune from the beginning.
Cooler air is more dense with oxygen, which means more fuel for combustion,which means more power....When I compared my intake temp from inside the engine compartment vs. from stock air box ther was a 50/60 degree temp difference during the summer. I noticed the difference in throttle response instantly. Im also using 2 oil catch cans which prevent blow by gases from being sucked back into my intake for reburn, and robbing octane.Its a bunch of small things that can help pull every little bit out of these engines. I have an idea for converting individual plug mounted coil packs from a 5.0 on my 4.0 by dissecting the one pc coil pack and fabing a wire harness from it that delivers the firing order and powers the individual coil packs. Do these motors experience spark fade above 3000 rpm?...probably not, but you wont see another one like it...lol
RhodesCD,
Since you chose 98tm ohv heads my advice is that you use 2.9L headers and have the ports matched to them. Ford cut the 94 and 95tm exhaust ports perfect for 2.9L headers but the inlets to the exhaust manifolds they used were oversized to try and trick/beat emissions; this ruined the exhaust velocity as will a set of 4.0L headers.
To be clear bpsinned is using 90tm heads in a 97 4.0L; he can safely add 94, 4.0L OHV pistons and run very near stock compresion. He can use 4.0L SOHC flat tops and raise the compression a whole point because he is using the big dish 90th heads.
With 97TM HEADS you can use 97 ohv pistons and mill the heads 0.030" and realise a full compression point. I have been told that a 97 EEC will run 95 or 97 4.0L ohv pistons no problem but that it will not get along with 94 shallow dome pistons and using SOHC 4.0L pistons is definitely not recommended for that EEC.
Neither of you need more than #19 injectors; they are supposed to be plenty through 250hp.
bpsinned,
If you haven't bought your cam or springs yet, I can help you save some money. My custom reground cam only cost $200 including shipping both directions from Oregon Cam Grinders of Vancouver Wa (they offer both Comp Cam profiles). My springs are a double set used in Ford V8's which worked out perfect for the new lift needs, the set was only $80. I have the part number if you are interested. I also have the cam specs that I'm using, though they are specific to the flow characteristics of my engine and used with an automatic.
I strongly urge you both to consider having your stock T/B bored, though not the cheapest procedure, that extra 3hp across the RPM band is a solid gain!!!
Also, since you are both stepping into higher compression power, don't skimp where money is best spent; spend the extra couple dollars and get the ARP piston rod bolts. If you are adding headers, Stage 8 offers great locking header bolts; there is nothing better than torquing header bolts once, FOREVER
FYI; the heads need a little work but of the 4 pieces that lower intake manifold came back the lightest. Just like with it's sibling the 2.9L, the lower intake manifold required the most material removed.
Any tips or notes on how to use the ford pcm software?
It's an older Street Smart Design with a carbon fiber shield box, air comes in from underneath, but it isn't totally sealed
Those monitoring aspects like air intake temp are great, but wouldn't I still need to get a programmer for tweaking the pcm to take advantage of the compression change to 10:1 with the 422 comps cam, bbk throttle, heads ported & polish with expanded exhaust ports, jba shorty headers, upper & lower intake ported ?
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