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hi all; very shortly I hope to have my 'new' LS4 in the garage and onto the engine stand for a full refresh. In my rebuild I plan on eliminating the DoD. I have a couple of questions that relate to the DoD.
I have read a number of threads to try to find out the actual role of the OPSU and whether it has to be relocated to another place and thus avoid the problems with the intake manifold. Or can it be pulled and the hole simply plugged?
It strikes me that this thing has 5 wires, so it is not just a simple sender, but I am not sure what it actually does. Is this supposed to be in a certain oil passage that feeds the DoD lifters? Is it located due to solenoids or some other devices? Is it in fact a 'sender-TO' the lifters (so sends oil I guess) or is it just a sensor for the ECM?
I have looked at various mfr's 'kits' for eliminating the DoD. They seem to all include head gaskets. Why would I need to pull the heads to eliminate the DoD?
My uninformed plan was to simply replace all the lifters with conventional ones and have the DoD programmed out, but are there still active oil passageways that will need to be plugged or treated in some fashion?
I haven't been able to find this particular info on the forum; if it is here I'd be happy with a pointer or link; thanks in advance for any info!
The OPSU senses the oil pressure. You can relocate if you like, modify the existing OPSU bung, or get a whole new valley cover.
The reason they include head gaskets is because you have to pull the heads to get to the lifters. Which if you're going to have the block on an engine stand I'd also cam it and switch oil pumps while you're at it. Lastly for the oil passages yes there are DoD specific oil passages which a new non-DoD valley cover would block off. I personally went with the Katech valley cover and OPSU bung, which is expensive ($250 for them both I believe) but solves all of your OPSU relocation problems. There are cheaper alternatives if you wish to go that route however.
You can relocate the OPSU to oil filter sandwhich adapter for ~30bucks from glowshift. Great alternative to Katechs senselessly over priced valley cover. If youre deleting the DOD then all you need is a LS2 Valley cover or Escalade non dod valley cover for ~30bucks, which blocks the oil passages and all youll need is the oil filter sandwhich adapter to relocate the 3 wire OPSU too. https://ls1tech.com/forums/ls4-perfo...installed.html
The 5 wire connector youre reffering too is the DOD solenoid connector which is not needed as long as the DOD is shut off in the PCM.
as IVloses said though while you have everything apart cam that ******, get new lifters, id also add the the LS2 timing chain damper as well.
Great; what I needed to know.
VLOM? still trying to figure that one out... help?
I'm old school SBC stuff so I'm learning as I go. This is all very helpful; thanks guys.
The OPSU didn't look like it did anything (ie it wasn't any kind of actuator buried inside) but I wanted to be sure. Any LS2 valley pan will work? Will start looking.
Yes, I am going to cam it, already have a ported aftermarket LS6 intake manifold; LS7 exh manifolds, LS6 injectors, with the plug adapters, coil packs, wiring harness and a bunch of other stuff and I don't have the engine yet!
(waiting for space to open up in the garage... this Thurs?)
I have a complete new sandwich kit now; will wait to see if it is the same size and thread etc. I will be space-challenged (another fiero) but will triple check what fieroguru did in his threads. Oil pump? Is there a problem with the LS4 unit? Don't recall seeing anything on that; was planning on shimming the pressure relief spring a tad and ensuring the pickup was brazed to the tube and pump, assuming it is that style which I think it is.
Great; what I needed to know.
VLOM? still trying to figure that one out... help?
I'm old school SBC stuff so I'm learning as I go. This is all very helpful; thanks guys.
The OPSU didn't look like it did anything (ie it wasn't any kind of actuator buried inside) but I wanted to be sure. Any LS2 valley pan will work? Will start looking.
Yes, I am going to cam it, already have a ported aftermarket LS6 intake manifold; LS7 exh manifolds, LS6 injectors, with the plug adapters, coil packs, wiring harness and a bunch of other stuff and I don't have the engine yet!
(waiting for space to open up in the garage... this Thurs?)
I have a complete new sandwich kit now; will wait to see if it is the same size and thread etc. I will be space-challenged (another fiero) but will triple check what fieroguru did in his threads. Oil pump? Is there a problem with the LS4 unit? Don't recall seeing anything on that; was planning on shimming the pressure relief spring a tad and ensuring the pickup was brazed to the tube and pump, assuming it is that style which I think it is.
Thx
GP
Vlom=valley cover.
The opsu the sensor that screws in by the throttle body.
The 5pin connector under the intake manifold is what actuates DOD solenoids.
What year is your engine? 05-06 have 13\16 thread iirc
07-08 are diffrent size.
The DOD oil pump is super high volume of all the Ls oil pumps. When dod is deleted all that volume is not needed instead you'll want a ls6 oil pump which can maintain pressure better at higher rpm.
As for brazing there's no need the pickup bolts on to the pump. Its a pretty solid unit. The only mod that might be worth wile is picking up a crank scraper from improved racing.
.... id also add the the LS2 timing chain damper as well.
Again this is the kind of thing that is really useful; I will go with the 3 bolt cam and 3 bolt, 4 reluctor timing set; I'd like to use a double roller type but CC (at least for one) doesn't offer that combo; it is all single roller chainsets for that particular application.
What is the plus for the LS2 timing chain damper?
This is off-topic for this thread, but....
Fieroguru (might be in his more detailed thread) installed a stock coolant 'tube' that apparently joins all 4 corners of the block at the heads, is supposed to help with coolant flow and is found on (he thinks) 2000-ish LS equipped trucks.. Does anyone know for certain what vehicles would have this? It fits under the intake manifold and above the valley pan.
This one, below:
Since my plan is to take the car to the (roadrace) track and run it for extended periods, I want to have everything I reasonably can to keep it within temperature and pressure parameters.
Thx for the ongoing info and support!
GP
Photo credit: 'Stolen' from Fieroguru's build thread ;-)
Again this is the kind of thing that is really useful; I will go with the 3 bolt cam and 3 bolt, 4 reluctor timing set; I'd like to use a double roller type but CC (at least for one) doesn't offer that combo; it is all single roller chainsets for that particular application.
What is the plus for the LS2 timing chain damper?
This is off-topic for this thread, but....
Fieroguru (might be in his more detailed thread) installed a stock coolant 'tube' that apparently joins all 4 corners of the block at the heads, is supposed to help with coolant flow and is found on (he thinks) 2000-ish LS equipped trucks.. Does anyone know for certain what vehicles would have this? It fits under the intake manifold and above the valley pan.
This one, below:
Since my plan is to take the car to the (roadrace) track and run it for extended periods, I want to have everything I reasonably can to keep it within temperature and pressure parameters.
Thx for the ongoing info and support!
GP
Photo credit: 'Stolen' from Fieroguru's build thread ;-)
Sorry for the typo i mean LS2 timing set, its a single but is stout as hell. You do have other options like a C5R timing chain if you want, youd have to lookinto the specifics though in what you really need. Id say the double chain is definatley overkill though for your application. As for the coolant crossovers, early LS1 camaros came with them stoc, Theres also AN adapters so you can just do it youreself.
What kind of application is this motor going into?
it's actuallyl a fiero according to the gov't... which is just fine. I got the specs for the real McCoy and my plan is to beat them in every way... except perhaps for comfort which is ok with me!
With the F40 6 spd manual; which is sitting in my garage at the moment...
So fieroguru's build is of utmost interest to me, as are some of the pieces he is turning out.. like a 2" thick aluminum flywheel....
Here is one on ebay.
http://www.ebay.com/itm/1999-2007-2000-4-8-5-3-6-0-CHEVY-GMC-Knock-Sensor-Steam-Vent-Lines-Silverado-/221576765517?pt=Motors_Car_Truck_Parts_Accessories&hash=item339701204d&vxp=mtr
The last one of those I worked on, I put this in:
You do such nice work, Paul. It's an inspiration to me to do better - really! While I don't have the equipment and tooling you have, I can still pay more attention to detail, fit and finish.
Just bought a cabinet sandblaster from Harbour Freight so no more rusty parts and better looking paint jobs on everything! I'm also going to see if I can get a 'decent' but still small, sheet metal bender for the same reason. (I'm space challenged...)
I'm guessing this is an 'old school' SBC for me to reminisce over; but still upgraded to FI. Still aluminum? Very nice, which is your signature!
GP
I think the most HP the real 308's ever had was in the 260-ish vicinity. So that won't be hard to beat. I want it to turn better and stop quicker as well. Will be very interested in how close I can get my corner weights; the car is quite stripped out as we WERE making it into a race car (it got declined by the series as it didn't have the stock body...) We were not amused...
I have some very stiff, short travel coil overs but not sure I will use them or at least, just yet. I think when I checked the clearance of the rear struts to the 10.5" rims and 315 tires it DID clear but only just. I have to recheck that with coil overs in place to see if it will actually work. Otherwise I might make up some inboard shocks and the necessary links and mounts. Have to see how much room there is over the 5.3 when it is in place. With the 3.9 V6 it is doable but I keep being surprised with how physically BIG the LS4 seems to be!
I have the other 308 specs and think I can top them and that's using reliable north american parts that I can find in any town (also part of the goal).
Finding the sway bars that Herb Adams put in his track car is almost impossible, guru; if you are looking for a product line you might consider that! I'd be in line! ;-) He ran 1" front and 1-1/4" back; this was in the 84-87 models which you might be allergic to(?) but it IS virtually impossible to find a set.
Re: this thread that I am self-highjacking so well:
the Ebay pic said knock sensor and steam vent..
I don't see where it actually would 'vent' steam so I guess it is almost a 'pressure relief' for any corner that develops steam; it 'dumps it' to another corner based on a very localized increase in pressure at that corner (to a lower pressure corner that isn't developing steam. Interesting.)
I don't recall seeing knock sensors in the valley pan area; did I miss them?
The steam pipes... why change what the LS4 has and works as in it allows trapped air/steam directly to/ from the top of the system and reservoir. Remember theLS4 has a completely different front assembly.
The knock sensors on the LS4 are located on the sides of the block, one on each side.
The steam pipes... why change what the LS4 has and works as in it allows trapped air/steam directly to/ from the top of the system and reservoir. Remember theLS4 has a completely different front assembly.
The knock sensors on the LS4 are located on the sides of the block, one on each side.
re: ADDCO - yes; have checked everywhere. The 'reverse' sizing (smaller front than rear) is what makes it an unusual combo. Herb Adams is a fiero and general GM "Handlingguru" but he doesn't manufacture anymore..
I'll have to check my engine when I get it to see what the arrangement is for supplemental cooling. Interesting that they put this extra tubing (from what I can tell) on SOME engines (truck only?) and not others.
re: ADDCO - yes; have checked everywhere. The 'reverse' sizing (smaller front than rear) is what makes it an unusual combo. Herb Adams is a fiero and general GM "Handlingguru" but he doesn't manufacture anymore..
I'll have to check my engine when I get it to see what the arrangement is for supplemental cooling. Interesting that they put this extra tubing (from what I can tell) on SOME engines (truck only?) and not others.
to put it simple, trucks that were equipped with this typeof system had the engine much lower than the radiator and air and such naturally found its way. Also these engines equipped with the 4 point system had a bleeder in the system that the LS4 does not.
to put it simple, trucks that were equipped with this typeof system had the engine much lower than the radiator and air and such naturally found its way. Also these engines equipped with the 4 point system had a bleeder in the system that the LS4 does not.
Excellent point; just as I pressed 'post' for the last one I started thinking about that item! It sure looks like this tube assy would create a 'trapped' high point by itself. I believe fieroguru has this in place for his car engine and hope he chimes in on what he has done about it (or hasn't had to, somehow)!
Pull the rubber hose off while the engine is running and you will find that a steady stream of water comes out the end. They are called steam lines, but water flows through them when the thermostat is closed and takes any air bubbles with it. On a running engine air can not be trapped within the lines - regardless of elevation difference to the inlet of the radiator.
10-20-2014, 05:46 PM
Eliminating DoD - specific questions 
