Hmmm, might have trouble makin that IAC connection.
Hmmm, might have trouble makin that IAC connection.
yeah I dont know why it wont let me directly upload a second pic...Originally Posted by TriumphR3
just linking the second pic from another forum. I got this adapter as its got a square base so I can rotate it.
doesnt bother me if its sideways as it'll be easier to get 90s on vacuum connections from cars at the junkyard. the 91 truck 350 throttle cable is extra long as well so I dont care if it swings around in a loop to make proper connection. I can just bend up some flat bar to make a linkage bracket.
It appears the TPS is missing? I curious, is it the Early style TPS (3 pin flat) or Late style TPS (3 pin round)?
this is just one I had laying around for mock up purposes. when I go to the u-pull this weekend to grab a couple more sensors/plug connectors I'm going to grab one with all the sensors, mounting bolts and injectors, etc. hoping to score an air cleaner as well. at least these are my "plans" at least. its getting to be slim pickins with the TBI stuff these days.
my harness I have is from an 88 1500 so 3 pin flat (at least I'm pretty sure this is it?):
any idea what the 2-wire sensor with the inlet/outlet hose is (cant see it in the pic, its attached to the backside of the bracket)? I'm pretty sure the other two are the map sensor and the EST (or ESM)? havent had a chance to go through the harness yet to determine which other sensors I still need to grab. I hope to do that tomorrow or thursday.
I'm going to attempt to grab a complete throttle body with mounting bolts/throttle body riser (or whatever that ring is that sits on top of it) injectors/IAC/TPS as well as a coil with harness connector, fuel lines, o2 sensor connector, and air cleaner assembly. I think thats pretty much all I will need though? I plan to buy a new o2 sensor as all the cat pipes are normally cut off at the u-pull so those are usually missing but I know a 92 truck there still has the connector dangling with whats left of the o2 sensor.
Last edited by stackz; 03-28-2023 at 11:07 PM.
no clue why the pic is so small. per the pic below looks like the sensor not pictured above is the EGR solenoid. the big sensor is the ESC module (will read up on what that does) and yeah, map sensor. so yeah, I think my buy/find list is pretty complete.
2012-07-19_021611_egr.gif
Last edited by stackz; 03-29-2023 at 01:15 AM.
Correct. On the carbureted engines used in medium duty trucks and marine applications vacuum advance was often replaced by a flat plate. There are aftermarket copies available. If you do a search for HEI vaccum advance lock out plate you're likely to find a number of vendors.I'm curious why he completely removed the vacuum advance unless its for asthetics? I mean if you dont hook it up, it wont be used right?
I'd like to suggest using a throttle body from a 2.8 powered vehicle for your conversion. With the large throttle bores of the 4.3 and V8 throttle body and the relatively low air demands of the engine it may be more challenging to tune small changes in throttle angle. Additionally you will need to work to get fuel delivery correct at idle and low rpm due to the amount of fuel delivered by the injectors. The 2.8 / 3.2 throttle body has much smaller bores and it already includes injectors sized appropriately for a lower horsepower engine.
If you need a really long throttle cable look for one from a late '80s to mid '90s van. The van wiring harnesses are very long also because the ecm was mounted under the driver's seat.the 91 truck 350 throttle cable is extra long as well
been sitting and thinking on this. I get the bore sizes and all but the 235 vs the 4.3 (262) isnt that much. I think what you are saying is that I can only reduce the injector duty cycle so much at idle but I can increase it as much as I want. right?
my thoughts.
I get this. maybe I'll start out with the 2.8/3.2 injectors (IF I can find them), would rather not just start buying up new injectors at $60/pop from rockauto vs $5/each at u-pull (if I can find them). Along these lines, I can use the larger throttle and just toss in the smaller injectors and then put the injector size in the tune right? I'm initially going to use the 88 1500 4.3 ecu to get it running but from what I've seen with others...I know I'll need to fine tune this thing or I will always have issues. already eyeballing the for sale sub forum for that pre-chipped ecu with chip. then get a burner or maybe that new ostrich clone? which, if I read right, once I get tune right, burn to chip and be done. but at least the ostrich will let me quickly swap out injectors and change scaling, etc (no, I have not downloaded the tuner software yet, just browsing available videos and such at this point to get up to speed).
I'm still trying to figure out how to delete the ESC/knock sensor as well. If the legacy kit from affordable fuel injection can come with the 7747 ecu with this stuff tuned out and/or bypassed through the wiring, then it has to be sorta simple. I tend to "learn by doing" but with a bit of "pre-education" so while I'm gathering parts, I'm doing my pre-education. it just seems most of the ESC/knock sensor stuff is assumed to be pre-learned from the online stuff I am finding. people just assume you know you can bypass the ESC by twisting wires together. um, ok? which ones?
I assume also the knock sensor stuff is like the EGR stuff and I can eliminate it in the chip itself with a tune?
Posting Permissions
Reply With Quote
Bookmarks