Hi guys,

Over the past couple months I've learned a lot from this board just by reading the posts and projects you guys have done. Thanks! Ok, now on to my question...

I'm swapping a freshly rebuilt engine into my truck ('95 GMC Sierra GT) this weekend to replace the oil burning pinging hunk of iron that's in it now. I was hoping I could pick your brains on the best way to go about setting up the new engine fuel and tuning wise. I have been playing around with the tuning for the past two months with exhaust and intake upgrades.

The engine going in is going to basically be stock. It's a 350 with swirlport heads (for torque), but it will have a flat tappet 206/212 Comp Cam on 112LSA. It will also have shorty headers and an injector pod spacer put on during the swap.

What I'm wondering is can I break in the stock cam on the factory tune at close to stock fuel pressure? According to Desktop Dyno I should be making somewhere around 280hp with it tuned right, and using the stock 61lb injectors I need somewhere around 20 pounds of fuel pressure (i think lol). Should I just set it to 20lbs off the bat and edit out the extra fuel in TunerPro and add it as I need it?

I'm not sure what the best way to go about this is. I need to make sure it survives break-in and can do a couple runs on the highway to seat the rings.

If anyone can offer any advice it would be greatly appreciated!

Cheers,

John

 

just out of curiosity, if you don't have a thirdgen, why become a member of TGO in the first place?

www.fullsizechevy.com is a gigantic forum, and they'd probably have the same technical knowledge. Especially of the special needs of your truck...

 

why not become a member of TGO? I think theres pleanty of good knowledge of chevy engines (transmissions, rear ends, etc.) on here, so I'd say its a compliment that this guy decided to ask here! Now if he was asking where to buy interior pieces for his truck or how to fit big-*** mud tires, thats a different story, but i'd just like to post this in defense of this guy. Good luck man!

 

Alright, just saying...

That's not far off stock as far as motor modifications. I'd run the stock tune, and break in the cam. Be careful, I wiped out my first cam last spring, it's no fun. Just make sure you've got GOBS of lube on the lifters and cam lobes, and EOS in the oil. Anyway, you should be able to use the stock tune to break it in, and probably even to give it a jog on the highway and let it stretch it's legs and set the rings. Then i'd check the logs and play with tuning. Perhaps check in at the TBI forum for more TBI specific tips on tuning. Fast355 is probably a good resource for you.

 

Sonix,

Thanks for your help, I appreciate it. I figured I'd ask here first because it's more of a tuning/TBI related question and there seems to be a lot more knowledge running around this board for that compared to fullsizechevy. I find the DIY PROM and the TBI forums here are awesome.

Anyways getting back to the truck, I'll make sure there's lots of lube on everything, but what does EOS in the oil mean?

What should I do about the fuel pressure, or at least in the beginning? I bought one of those high pressure pumps from xtreme-fi off of ebay... so I should be able to get the pressure high enough.

Fast355, any input?

Thanks guys!

John