Vortec -> Carb now -> TBI

[PJG1173]

Ok, so I think I've collected enough parts for my carb to TBI swap. I've been working on soldering up my wire harness the last few nights. I started placing the sensors on the motor yesterday since it wasn't raining. I got to the knock sensor and ran into a problem. since I have block hugger headers the knock sensor won't fit between the collector and the block when put in the drain hole at the bottom of the block. Is there an alternate location to put the knock sensor or can I do like what the guy did in the below link?
http://www.chevytalk.org/fusionbb/showpost.php?post/1468867/cto_session_id/ac73651d27de2e46ba6ca44c74730d78/

[RobertISaar]

that route has been suggested on TGO many times, so it must have merit.

[pmkls1]

I've wondered myself about mounting one in a similar method. The new style GM knock sensors are designed to mount in a similar manner with a thru-bolt that doesn't enter a water jacket. I'd think that it probably works ok with at most a little fine tuning to the knock parameters.

[RobertISaar]

some older applicatons didn't mount into a water jacket either.... see ~85 and up 60V6 applications for example. i don't think it's that critical.

[EagleMark]

That works fine. Although it does de-sensitize the reading a little. Very handy with conversions and to reduce false engine noise knock counts. Just have to verify knock counts when done. When in block I usually back off timing 2 degrees, with the elbow 4 degrees. I am conservative with spark and have never hurt a motor!

[pmkls1]

some older applicatons didn't mount into a water jacket either.... see ~85 and up 60V6 applications for example. i don't think it's that critical.

That makes sense as the Gen III LS engines use a standard threaded style knock sensor that doesn't mount into a water jacket either. I'm guessing that on at least some applications the mounting location of the knock sensor was a matter of convenience in order to avoid expensive block re-tooling maybe ?

[RobertISaar]

possibly. or just attempting to locate the sensor in a central spot, regardless of water jacket location.

[PJG1173]

Hmm would a bolt through LSx style work with a 7427?

[RobertISaar]

depends on resistance, and what kind of ESC setup you're using.

with older OBD1 stuff with the external ESC filter, they ran 100K ohm sensors.
with the OBD1 stuff that have ESC filters internal to the ECM(MEMCAL), they ran 3.9K ohm sensors.
when OBD2 happened, they moved back to 100K ohm sensors, but used a different style of connector.

so, if you could use an external knock filter with a 7427, entirely possible.

[CDeeZ]

Damnit, where is that little popcorn eatin smiley guy now that I need him. This is interesting stuff.

I think Grumpy was one of the first to suggest using a elbow mounted KS years back. Especially useful for quelling false knock counts from a rumpity rump engine, as Mark mentioned.

[EagleMark]

Damnit, where is that little popcorn eatin smiley guy now that I need him. This is interesting stuff.

I think Grumpy was one of the first to suggest using a elbow mounted KS years back. Especially useful for quelling false knock counts from a rumpity rump engine, as Mark mentioned.He did. Also did a bunch of testing involving ESC modules and sensors. But I beleive it was lost as I looked pretty hard awhile ago to find it. I it was lost...
:popcorn:

[JeepsAndGuns]

I have read about that a few times on here, but the first time I have seen a picture showing exactly how someone has done it. Very interesting way of doing it.
I really should give this a try. I have never been able to use my knock sensor because of false knock. It would be nice to be able to use it.

[Six_Shooter]

I've done it differently on a few applications.

On my Nissan 2.8L I6 (Using Delco EFI), I used a 45* brass "street elbow." I threaded the elbow in place of where I had the knock sensor, then threaded the knock sensor into it.

[pmkls1]

I have read about that a few times on here, but the first time I have seen a picture showing exactly how someone has done it. Very interesting way of doing it.
I really should give this a try. I have never been able to use my knock sensor because of false knock. It would be nice to be able to use it.

I have considered this as well. But, I do have some mechanical noise that may be leading to some of my false knock counts that I will be repairing and I will re-evaluate after I make the repairs. GM uses the thru-bolt style knock sensors on everything nowadays and there are multiple part numbers for them. The next time I have a chance to grab a couple from a junk engine I will check the resistance of them and see if there are any that may work with the 7427 memcal.

[1project2many]

I just picked the wrong knock sensor. :) When I built the '57 I used a sensor from a Saturn with 1.9 PFI engine and ran a 3/8" die over the 10mm threaded stud. Since the '57 engine mount is attached to the front of the block, I used one of the holes on the side of the block for the sensor. It picks up knock but it's not overly sensitive. And boy oh boy did I get blasted on GMECM for mentioning using a knock sensor from the wrong bore size engine to discourage false readings!

Mark, if you have some idea of a post, or a note, or how Grumpy's tests were worded I may have a few saved messages here. In the beginning I saved each and every post I saw come across those lists.

[EagleMark]

I've heard about it, sure I've seen and read it, pretty sure I had it on my old laptop that had a cup of coffee go through keybord and out USB ports. But I can't remember where, DIY or early ThirdGen? Just the obvious keywords? I searched pretty hard when we were working on the knock sensor, ESC and Memcal stuff.

[CDeeZ]

On my Nissan 2.8L (http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&catId=6000&item=251113104639) I6 (Using Delco EFI), I used a 45* brass "street elbow." I threaded the elbow in place of where I had the knock sensor, then threaded the knock sensor into it.

Were you experiencing false knock?

[PJG1173]

I remember reading about testing of different knock sensors on tgo, but I can't find it again either. I,m going to see what I can dig up at Lowes tonight. I would really like to have a functional knock sensor on this build. The motor is real picky about timing

[Six_Shooter]

Were you experiencing false knock?

I think some was false.

[PJG1173]

So not much luck finding a 45* fitting to stick in the block for the knock sensor. I may take the header off and see if I can put the knock sensor and see if it will clear with the header back on. I have to weld a crack in the collector anyway. I think I'm working backwards on this. Another question I have is since I have a NP208 tcase with no provission for a VSS I found one of these at the right price (free)
2886
Would I be able to use this? If so would I still need a VSSB/DRAC?

[belaw]

Another question I have is since I have a NP208 tcase with no provission for a VSS I found one of these at the right price (free)
2886
Would I be able to use this? If so would I still need a VSSB/DRAC?

I'm a fellow TBI noob and I've been trying to figure out "hardware" issues- including VSS for a transfer case- too.

That's an 8 pulse (8,000 pulses per mile) speedometer sender, probably for an aftermarket gauge. Unfortunately a '7427 requires a 2-pulse input for VSS. Adding a VSSB/DRAC won't help with that sender, because they're calibrated to receive a 40 pulse AC signal.

If you can find a 2-pulse DC/square wave sender you can feed the output directly to your PCM . The VSS from Jags That Run is the only plug-and-play unit I've found.

[PJG1173]

IDK what that cable is/was for. i figured its worth a shot for the price. having the VSS isn't a requirement, but it would be nice for idle.

My other alternative is to get the toyota speedo working and see what kind of signal I can pull from the cruise control. I think with some crafty grinding I can get the toy speedo cable to fit the chevy transfer case.

This is what was rigged up on my buddy's truck when he bought it. not sure who did it but it works.
2887

[belaw]

I'm 99% sure Toyota used a 4-pulse generator; I would check on Mud or Pirate before spending a lot of time on it.

[PJG1173]

Just an update. I finished the wire harness over the weekend and installed it. I also roughed in a startup tune for it definately going to need some work. of course i forgot to run a wire for the coil which was real frustrating as I sat and stared at the schematics for an hour or so... then of course the transposed wires on the 454 tbi didn't help it run when once started. acording to UPS my WBo2 should be here today so I can really start trying to tune this thing. a few questions before I start on this.

base timing. how much is too much? when carbed this setup ran 21* initial 0* vac and 0* mech. it ran decent but would idle real rich. I figured it was because the carb was about toast, but now with efi it does the same thing. right now I have 10* base and 21* in the idle area of the spark table. no mater how much fuel I give or remove at idle it still puffs black/grey smoke and makes your eyes water. I adjusted the ve table for the best possible MAP reading, but it is still pig rich. I know with this cam I have some "self egring" or reversion going on from the amount of valve overlap. I have read on other forums that people have ran up to 30* initial timing with this cam carbed. would that still be possible EFI? I'm assuming so.

also does anyone know how to make $0D go open loop idle?

info on my build
87 Toyota 4runner
chevy 355
comp extreme energy 4x4 280hr cam
ported and polished vortec heads
air gap vortec intake
block hugger hedders
th350 trans
3000 ACC stall
5.29 gears
44x18.5x15 super swamper tsl
454 TB
454 injectors 83#
16168625 ecu running $0D

[EagleMark]

Min tempreture for closed loop should work to keep in open loop and with that cam will probably have to keep it an open loop idle, or just open loop always and tune via wideband.

30 to 35 degrees advance and more is needed for big cams and the reversion acting like an EGR, timing must drop right after that, can do with EFI and not carb distributor. Watch your Warm Spark Bias to see where timing really is compared to Main Spark Table.

Raise idle to 900 plus for a start.

Closed loop at idle with a cam like that is giving you wrong info, it's lying!

There's a Vortec head bin around here somewhere would be a good start for timing table after adding timing to idle.

It's going to idle rich and smell bad even running right, don't use your nose for AFR, it's a bad gauge.

[PJG1173]

once I get the WB installed and make sure my cobbled up knock sensor setup is going to work, I'll try to experiment with different settings. right now Idle is set for 850 as it was when carbed. I have also read on various fourms that people set idle around 900 +/- 50 for similar cams. I was kind of thinking that this would end up being a strictly open loop tune. right now it moves on its own power so its not stuck in front of my garage so I'll mess with it as time allows.

[EagleMark]

Wait, what are the cam specs @.050 ? What I saw online was not that bad... should be able to run closed loop... but it was 1000 RPM to 7000 RPM range.

[belaw]

There's a Vortec head bin around here somewhere would be a good start for timing table after adding timing to idle.


Since Mark shared this with me in another thread I thought I'd pass it on:

http://www.gearhead-efi.com/Fuel-Inj...ull=1#post2902 (http://www.gearhead-efi.com/Fuel-Inj...ull=1#post2902)

[PJG1173]

The cam is this http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=167&sb=2 duration is 230/234

[EagleMark]

I've done that before, looked up a cam and had differant specs. Yours is more radical then the one I saw, power from 1800 RPM up = not good idle...

[PJG1173]

I took it for a spin this morning before work today now that the WB is hooked up. I am quite supprised how lean it is at cruise with the BB injectors. of course cruise for this is 2800 rpm because of the stall. definatly thinking OL all the way. Hopefully I'll have time to get a good datalog this weekend see what is really going on. as far as idle goes im not too concerned with idle quality as much as it fuming me out of the truck at stop lights. any one have any suggestions on what parameters to change with this lumpy of a cam for idle?

[PJG1173]

I had a chance to go out and log some data. not as bad as I expected but :yikes: there were a lot of knock counts. I didn't see much retard if any though. it wasn't audible either but then again the truck is pretty loud so I may not have been able to hear any spark knock. how do I tell if its false knock or not? could this be caused by the knock sensor not being in the factory location? I'm going to pull 2~4* of timing out of the areas it detected knock. Also my VE is in the mid to upper 90's in some areas that are showing lean. which would be better turning up the fuel pressure or lowering the flow rate constraint of the injectors?

[RobertISaar]

you have knock counts, but not knock retard? that would imply that ESC isn't being enabled for one reason or another(coolant temp, RPM, MPH, etc).

[PJG1173]

you have knock counts, but not knock retard? that would imply that ESC isn't being enabled for one reason or another(coolant temp, RPM, MPH, etc).

I do have some KR but not in all cells where knock was detected. looking at my bin I see minimum MPH for KR is set at 3mph. since I don't have a vss I would assume this should be set to 0mph. the other two scalars is min RPM which is 1400 and min temp which is 74.8c. do all these need to be met before KR will happen or just one?

[RobertISaar]

i'm not familiar with $0D specifically, but generally, all of them need to be met.

[PJG1173]

Ok, I pulled a bunch of timing so my max advance is 28* in part throttle cruise and 26* or less in the high map areas. This seemed to take care of most of the knock counts and all of the KR I was seeing. the rest seems to be false knock which I think is coming from when I lightly let off the accelerator and my trans/tcase chatters (really bad drive line angle). This thing is apparently hungry for fuel, real hungry. I'm starting to max out the VE table and still seeing AFR's of 15.6 or higher in those areas. I've brought PE in early 40% tps (with no delay). I am using the 5235231 454 injectors at 12.5 psi. using a $42 bin and the injector calculator I was able to convert the BPC to pph, which worked out to 83 pph. for the injector offset I took the injector bias from the same bin and multiplied it by the injector correction multiplier then converted it from msec to usec. It came out with some low numbers from what I have seen for other injectors (attachment). Do these look right? would it be better to increase FP to get the fuel I need or lower the listed injector flow rate? I'm assuming raise fuel pressure. I haven't turned this motor up yet so I'm also assuming I will need a whole lot more fuel over 4400 RPM.

[RobertISaar]

i'm a fan of increased pressure, but i also haven't touched anything TBI in a good 4 years.

[PJG1173]

Well using the injector calculator and by going off of what the speed shop estimated my HP to be I need 214#hr of fuel to be safe. I'm sure increasing the pressure would be better than fudging the injector flow rate.

[PJG1173]

Looks like I'll be getting a better fuel pump. the stock toyota pump doesn't seem to want to run over 16psi. which is weird since the stock motor was supposed to run at 27~38 psi at the fuel rail, so I would assume it would be able to push the TBI with an AFPR into the same ball park (not that I need that much pressure). I'll do a dead head test on it tonight to make sure its the pump and not the regulator itself. pretty sure its the pump though just put a new diaphram in the tb last night. I just want to make sure I have some wiggle room with my fuel pressure and not have the existing pump maxed out or the regulator turned up all the way.

[PJG1173]

I closed off the return line and the FP went up to 60 psi so I don't think the pump is the issue. I think i need a 18 psi spring. $26 from ebay with shipping is highway robbery. anyone know what the spring rate is of the 18 psi spring? I should be able to find an spring that will do the job at a hardware store.

[EagleMark]

Hammertime had them lined up from the MSC catalog, there's 2 one for up to 18 and one for over. But we never followed up with a Group Buy? They were like 5 springs for $7.90

EDIT: Here's the link:
http://www1.mscdirect.com/eCommerce/SearchServlet/Motion-Control-Fluid-Power/Shock-Absorbers-Springs/Springs/Compression-Die-Springs/Compression-Springs/_/N-77g66Z1yy8fp1Z1yy8hhpZ1yy9l5w?refinement=429017127 9&searchandizedOk=Y&currentMSCtt=compression+springs&currentRawInput=compression+springs%A2compression+ springs&currentMSCtk=All_MSC&currentMSCtx=mode+matchallpartial

[PJG1173]

Hammertime had them lined up from the MSC catalog, there's 2 one for up to 18 and one for over. But we never followed up with a Group Buy? They were like 5 springs for $7.90

EDIT: Here's the link:
http://www1.mscdirect.com/eCommerce/SearchServlet/Motion-Control-Fluid-Power/Shock-Absorbers-Springs/Springs/Compression-Die-Springs/Compression-Springs/_/N-77g66Z1yy8fp1Z1yy8hhpZ1yy9l5w?refinement=429017127 9&searchandizedOk=Y&currentMSCtt=compression+springs&currentRawInput=compression+springs%A2compression+ springs&currentMSCtk=All_MSC&currentMSCtx=mode+matchallpartial

cool, thats a reasonable price. is this the one up to 18 or the one for over?

[EagleMark]

That's 17 plus, the higher one.



Spring Rating (Pounds)
17.2500




Maximum Work Load (Pounds)
22.4100

[PJG1173]

just for grins and giggles I put the spring for the feed head off my weed wacker in my regulator. it was almost the same dimensions as the stocker with the exception that it was thicker. with the regulator set at the lowest setting I now have 22 psi. I changed the flow rate in my bin and put injector offsets I found on TGO posted by someone running similar pressure on the same injectors. needless to say my PW at idle is .4ms and its still rich with my idle ve table in the teens. it has definatly richened up cruise and I'm able to get into the 12's for WOT and only hit 36% DC. I haven't pushed it over 4400 rpms yet so not sure if this is too much FP or what. anyone have any suggestions? I've read about people using vac ref FPR to control this but would this work for $0d?

http://i1129.photobucket.com/albums/m515/pjg1173/IMAG0429.jpg
http://i1129.photobucket.com/albums/m515/pjg1173/IMAG0430.jpg

[RobertISaar]

36% at WOT?

sounds like you need more engine. :D

[PJG1173]

36% at WOT?

sounds like you need more engine. :D

LOL isn't that always the case? although at 4400 I'm still below peak HP. the machine shop that built the motor said they had dyno'd similar builds in the ballpark of 385~400 hp, so this is what I have based my injector requirements off of. DD2000 estimates it at 409 but I definatly think I'm falling short of that number...

[EagleMark]

I put the spring for the feed head off my weed wacker in my regulator. Don't think I've ever heard that one before? :laugh:


36% at WOT?

sounds like you need more engine. :DOr less fuel?

You don't need a Vacuum Referenced Fuel Pressure Regulater... so far your not even close to using the fuel you have. It would keep the pressure down and when vacuum drops get more pressure. And it's a PIA to tune.

Do your calculations, enter them and set flow CID etc... and forget it and tune the Main VE. Should have table done between 20 and 80% + - 5%. If not then calulations were off. Use the Wire Frame view in TP to smooth out your Main VE, Get BLMs in order. Then do WOT with WideBand using PE AFR or adder settings. Sounds like you have the Spark Advance tables done. If you have an aggressive timing table look out for added Spark Advance from PE, it's not needed if AFR is richer then Stoich and you have an aggressive Spark Table.

[PJG1173]

Ok so working my VE table off the WBo2 it is starting to look like a quarter pipe. At WOT I am still able to maintain AFR's in the 12's at 40% DC, high 90's in the high map cells of the VE table, and PE AFR vs RPM table set in the 10's for afr. It seems this thing wants a disproportionate amount of fuel at WOT compared to the rest of the time. Does this sound right? should I look at reducing fuel pressure?

[EagleMark]

Could be? If there's not enough fuel in VE then PE adds more fuel.

[PJG1173]

the PW at idle is really low (.4) the spray pattern is pretty poor along with idle quality (worse than normal). I think I'm going to drop the and set the injector flow rate a little lower than calculated to increase DC and see how that goes. should I try 18 or 20 psi?

[EagleMark]

Ok so working my VE table off the WBo2 it is starting to look like a quarter pipe. At WOT I am still able to maintain AFR's in the 12's at 40% DC, high 90's in the high map cells of the VE table, and PE AFR vs RPM table set in the 10's for afr.


the PW at idle is really low (.4) the spray pattern is pretty poor along with idle quality (worse than normal). I think I'm going to drop the and set the injector flow rate a little lower than calculated to increase DC and see how that goes. should I try 18 or 20 psi?Where are you now? From quote above it does not sound like less pressure is needed?

So what's a quarter pipe VE look like? Your not going to increase Duty Cycle at idle... but I agree that .4 BPW is low. So your low at idle and seems a little short up top? This is an indication of wrong calculations.


I put the spring for the feed head off my weed wacker in my regulator. I'm wondering if this was a good idea?

Is your fuel pressure gauge accurate?

[PJG1173]

pressure gauge is acurate. I swapped the spring for a different one I found at homedepot, so I have some adjust ability starting at 16psi. currently it is 22 psi with the 454 injectors (GM5235231*RPD). using the injector spread sheet these should be 107# at 22 psi so that is where I have the tbi flow rate set in the bin. I'll have to take a screen shot of my VE table when I get home. ve at idle (60kpa) is high teens.