I think what John is fishing for above is not the motor performance, but rather the "bolt" torque spec's to affix the upper half of the intake manifold to the lower half.

John, here is a link to a SAE chart for general torque guidelines based on bolt stretch. You likely are using grade 5 hardware (stock marine). Seeing how you are threading (torquing) into cast iron, I would have no concerns using these numbers. If I was threading into the truck aluminum lower manifold, I might reduce these by 15%

http://www.brakeproducts.com/ajax-uj/p29.htm

and another -

http://aplsweb.com/Topics/Torque-Chart.htm

EDIT: As far as bolt torque specs, I think in this application, the intent is proper gasket compression, not maximum clamping force. So I would not follow the generic bolt stretch charts I posted earlier in this thread. Gasket compression is independant of manifold material. Use the same torque specs as the truck manifold and I think you will acheive the proper gasket compression. I am open to comments and other opinions on this. Does anyone have access to the service manual for the marine motor application? That would end the speculation right there.



Last edited by Pecos on Wed Jul 27, 2005 11:00 am; edited 2 times in total

Got some work done on Pecos's DIY MPFI harness kit! I've got loom for it too but will not be putting the wires into loom until locations for all the bolt-on accessories (coil, evap, EGR, etc) have been choosen.

Lookin real good James.

No before and after dyno for torque curves? I guess I'll copy your installation and do baseline before and after on a stock motor once you are done.

Care to help me perform this conversion on my truck? I'll make it worth your while. =)

James B. wrote:

Got some work done on Pecos's DIY MPFI harness kit! I've got loom for it too but will not be putting the wires into loom until locations for all the bolt-on accessories (coil, evap, EGR, etc) have been choosen.

Looking good James! Very nice!

In case others need a basic refresher course on wire striping, crimping, soldering, splicing, and sealing of GM Metripack and Weatherpack style connectors, and general automotive wire harnesses assembly "best practices" for under hood applications, here are the DIY instructions to go along with the "kit". Remember, crimp, solder, and seal. You need all three for long term reliability. On page #8 of the below guide, automotive grade bathtub silicone calking called RTV (room temperature vulcanizing) is a good general purpose silicone sealant for wire splices, but should be applied to the crimped and soldered splice connection BEFORE heat shrink tubing is put in placed and heated. Inserting RTV into the ends of the already shrunken heat shrink tubing will not get you a reliable weatherproof seal for the long term.

http://www.powertraincontrolsolutions.com/download/tcu/wiring/Proper-Wiring-Techniques.pdf



Last edited by Pecos on Wed Jul 13, 2005 5:53 am; edited 3 times in total

Good work James. Looks like everthing so far is doable and repeatable.

Hog

postcleaning



Last edited by Hog on Thu Aug 18, 2005 10:11 am; edited 1 time in total

Hog wrote:

Stealth97 wrote:

Lookin real good James.

No before and after dyno for torque curves? I guess I'll copy your installation and do baseline before and after on a stock motor once you are done.

Care to help me perform this conversion on my truck? I'll make it worth your while. =)

I'll get the before and after ET, MPH and 60ft time for a stock NA L31. There will be gains, but how large and at what rpm. I just got my rear changed today, so its time for some full track passes. No vibrations and posi to boot.


PECOS Thanks for the soldering, info. That'll come in handy.

Hog

I'm getting my truck back next Friday complete. I will weigh the vehicle at a local scale, with a full tank of fuel, with me in it. I can subtract for fuel and give weights for the runs I make at the track. Weight is important for comparisons.

I will have a dyno done on my stock tune, and my westers tune. I have the TunerCat programmer, so I will begin programming out my stock motor (I KNOW I can gain 30HP more than westers, and gain it all through the curve as well).

I will also run the track at the local track in the coming weeks. I will post my stock numbers (expect some sucky times). Then, my big list will start, and the times will drop sequentially.

I look forward to seeing your truck, James truck, White350's truck, Burbmans, and anyone else with power adders (Ken, etc.) perform their absolute best this year. I'm only at the beginning of the performance journey, and I have a ways to go.

30 hp OVER a Westers custom mail order tune is a bold statement. I really hope Tunercat can unleash some serious gains for me also, over and above those from Fastchips.

Goodluck with the truck Stealth. You are off to an awesome start.

Hog

James B. wrote:

Got some work done on Pecos's DIY MPFI harness kit! I've got loom for it too but will not be putting the wires into loom until locations for all the bolt-on accessories (coil, evap, EGR, etc) have been choosen.

Looking very good James....I just received my inductive rpm pickup for my wideband since I could not get the multi spark ignition to work correctly by direct hookup...you may need to borrow this soon?

Ken

Thanks Ken, I probably will take you up on that!

Here is a color pinout for the CPI connector I just drew to add to this archive:


Tonight I got the old spider connector soldered in.


Everything is sealed up with clear silicone. I will get a picture of that tomorrow when it's cured and I put this all into wire loom. In the "spirit" of the original design, the wiring harness will still look like a spider. The runs are so short that I'm keeping them separated to minimize loom junctions where tape would have to be. Tape just eventually comes off and gets gooey.

Well im really tired right now but the manifold is installed. I will post up some information that i think will be found usefull for others which includes injector wiring if your not going to make the stock connector work, fuel line information, coil mounting information and probably a couple other things. Anyways i worked from 12pm to right now (3:40 am) and i worked from 10am-11pm saturday putting the engine together (ran into a lot of problems, will post those later also). Anyways the engine is in everything is bolted up, I just need to install the radiator, bolt the ac compressor up and put the belt on and its ready to be fired up. Tommorow i will probably be posting up some tips, hopefully some pictures, possibley a video, and some first impressions.

Pretty weird, eh?

rcfast wrote:

.....I just need to install the radiator, bolt the ac compressor up and put the belt on and its ready to be fired up. Tommorow i will probably be posting up some tips, hopefully some pictures, possibley a video, and some first impressions.

WooHOO!! PICTURES!! VIDEO!!!

The suspense is too much!

James,

That thing is looking great, looks like it could have been stock. This is a project I am very interested and think could use. I am going to keep watching for updates.

RCFAST I am excited to see what happens when you finally get it running..


RU

Ru wrote:

James,

That thing is looking great, looks like it could have been stock. This is a project I am very interested and think could use. I am going to keep watching for updates.

RCFAST I am excited to see what happens when you finally get it running..


RU

Its in and runs.. will post more information later, just busy cleaning everything up in the garage

rcfast wrote:

Ru wrote:

James,

That thing is looking great, looks like it could have been stock. This is a project I am very interested and think could use. I am going to keep watching for updates.

RCFAST I am excited to see what happens when you finally get it running..


RU

Its in and runs.. will post more information later, just busy cleaning everything up in the garage

It runs, AWESOME. This is a milestone in L31 Vortec history. Good work.

Hog

Ok well i will post some of my thoughts now that i actually have time. I spent over 30 hours these last 3 days getting the engine built and installed.
First ill talk about the engine build:
Saturday I was helping my machinist build my engine and we ran into a few problems when we where building it. First problem of the day is the number 6 rod hit the camshaft, it didn't on the old cam but this one is much bigger. So we took care of that but grinding the end of the rod a little. After that we where checking the heads for proper clearance and found that there wasn't enough clearance for the seals for the cam im running, so we ground down the seats for the seals. Well doing this we found that one of the valve guides was destroyed because of a rocker arm that had came loose on the old engine. We replaced the guide but then found that the seat had been messed up so bad from the guide that we had to press in a new seat. If that wasn't enough when we where re-assembling the head we found that the valve was also bent, so we had to replace that also. Not fun, anyways long story short on the engine it got all assembled but took way longer because of the added machine work that needed to be done. Now it has a fully forged lower end.

After i got the engine i got it home and installed the lower of the marine manifold, I also installed some other small things like the oil filter adapter, distributor, injectors, and fuel rails. Sunday I got the engine bolted to the engine mounts and the bellhousing bolted all up and all the accesories and stuff

Now for getting the manifold installed I soldiered all the wires and heat shrunk them. The one thing i recomend when splicing the wires is splice after the connector that makes the 4 wires into 6. The reason for this is if you dont splice those 4 wires all together it will not complete the circuit for the other injectors so the engine won't run.

As for the coil the bracket i made worked perfectly and the connectors where able to reach it. The wiring for everything i just routed between the fuel rails and it holds the wiring in place really well. I also routed the wires from the injectors up through the middle on each side of the manifold. I will try and snap some pictures and post them tommorow.

Now for the fuel lines. I ordered some adapters from pure choice and got lines also, I had them make 2 lines 1 8" and the other 7". When i bolted it up to the stock location it seems like the lines would fit better if they where actually shorter because with the length i got i had to zip tie the lines back a little to make them fit, if the lines where shorter this wouldn't need to be done.

I filled the engine with fluids and primed it, after this i started it and the engine started on the first try. I programmed the pcm for the bigger injectors (35lb@60psi) and left everything else the same (had a ed wright program for a 383 with slightly smaller cam). Went for a test drive and everything is running perfectly, checked the fuel trims and they where all within +-5%. So it looks like i won't have to do much tunning other than WOT and idle tunning. This cam i got lopes really hard and shakes the whole truck a lot, it also looks like my gas mileage has suffered severly because of it. I have some start problems where i have to give it gas until it finds the idle then its fine, but i can take care of that with tunning. Also i did a couple of low rpm 75% runs from about 2000-4500 rpms (i will be shifting at 6500) and it pulls WAAAYYY harder than it did before with the same parts (aside from forged pistons instead of hypers, the cam, and manifold) and this is at 75% not even up in its power band. Also on the 75% it actually ran a little rich, something that has never happened for me with the 383. I could never give it the fuel it wanted before. It seems like the PCM has no problems supporting the 35# injectors i have so far. So all and all it runs very good and im happy with everything except the gas mileage. Also as far as the EGR i just plugged the header and programmed out the EGR so there is no check engine light. I also plugged off the EVAP and dissabled those codes as well. I plan on getting the EGR and EVAP running properly, I just wanted to get it running first. I would like to get some video but i just have a digital camera to take video, so i will try that and see how that comes out. I will also try and snap some pictures tommorow and post all that up. Anyone have any comments or questions?

Thats awesome. Definitely great progress for this engine.

Wish I were still interested in getting it going. I don't think a 305 with a decent set of heads and cam will need all that though, seeing as the current system can support a 350 with no problems. I dunno, time may change my mind, but doubtful since I see a definite end in my ownershop of the Tahoe, and that end is 5 years from now.

I also wouldn't worry about mileage at all till the whole truck is broken in and tuned. I imagine you can get huge gains in mileage over the next few months.

Congrats on all you've accomplished in such a short amount of time. But you *really* need to get dialed in sooner than later. Ask Steve what happens when you run one too rich for any length of time. Go change your oil now!