Rebuilding my L31, need some opinions on mild upgrades.

[TylerZ281500]

your not a wealthy person so heres my question, is the motor blown? answer no then keep driving it and save for a crate engine, if it is same route crate engine do your research on them. i would never halfass a build and skip a tune with a cam and with motor work comes work with the rest of the driveline. so...i nlight of that place a budget triple it to make sure your comfortable with spending that as things add up fast, if your not ok with it do what you have to to keep it driving and let it be.

 

[Constantine]

I've never done a high performance / non stock engine build for a computer controlled vehicle with fuel injection.

when I mentioned running a camshaft without a tune, it was a question.
A question brought forward by my ignorance of what can be done with the factory computer system.
it may make sense to you that you can't do such a thing, but if you didn't know from experience then you wouldn't be able to make such remarks.

I'm simply trying to learn here.

The engine is not blown, it does run good.
although it has 240, *** mile on it and leaks from rear main, and behind the harmonic balancer.
It has also recently developed a haze from the exhaust when you first start it up in the morning like possibly valve seals/guides are past tolerances.

 

[TylerZ281500]

a build is a build, as for every build you build up to a specification or vehicle use, same here the only thing is is that yo know have limits. your factory computer can handle quite a bit of reprogramming, sure you can just throw eveerything in and hope it runs but a tune would make a world of difference, just like a carb if you tune it poorly you wont gete everything out of the engine if you tune it to max its potential it will react alot differently. now if you want to go past the limits of factory then 411 swaps are out there. lt4 cams are popular and easy, exhaust and stuff like that is rather timeless and easy hp.

the question is though do you have the budget for all new everything plus machine work if it comes to that? that means honing, line bores, boring, magnufluxing, valve jobs etc etc. otherwise read up and you can get yourself a decent 383 crate motor for pretty cheap nowadays. as far as camshafts, if you know how to properly selct one id start looking at the factory specs and reading up and seeing what people are having success with, with the computer controlled trucks your durations, lsa and such matters quite a bit more than pre efi where itll run somehow regardless of what you throw at it. within your tuning you could also delete knock sensors/ Air, egr and stuff like that.

with vortec you already have the advantage of a better head, a better computer system somewhat than tbi, and a mpfi upgrade where you can use a basic carb intake and elbow and be making plenty of power to keep you happy.

 

[Constantine]

Current Budget in pocket is $3500.
I would like to include the rebuilt engine or crate motor in that amount of money.
For the pricing of a reman. Long block from say O'Reilly auto, for example, and the parts included in replacing is about $2000.

I do agree we need to look into what I'm wanting performance wise and use of my truck.

My truck lost some performance when I installed the 285/75 tires and also some towing ability.
about the heaviest thing I haul is my Volkswagen (near 1800 lbs last time on the scale) on an 18 ft car hauler, unsure of weight but it has a steel diamond plate floor so pretty heavy.

I'm looking for some low end pulling power that is still highway freindly.

maybe a few external power adders and a good tune would help me out.
that's in conjunction with some tranny work to come after I recoup from the engine build/replacement.

I'm not sure that a good fresh engine wouldn't satisfy my butt dyno.
I'm sure some power has been lost due to mileage.

 

[Constantine]

Carry over from your other thread.

I've updated my supporting products to purchase.

2 engine oil cooler lines. Stick to GM or make some using fittings to replace the quick connects. The dorman ones SUCK.

3 water pump and thermostat. Always with a fresh engine. I always buy the delco thermostat.

5 felpro intake gasket set, felpro manifold bolt set & plenum gasket set. No need to replace the intake bolts. Use the good fel pro MS98000T comes to mind, it comes with all gaskets for about $60.

6) accell ignition kit with distributor. Junk, Junk, Junk. None of the after market crap holds up well. If you want to upgrade the dizzy look at this: http://www.ebay.com/itm/Ignition-Di...Parts_Accessories&hash=item4613d3f64c&vxp=mtr

You do not have angle plug heads. You need to look and see if your manifolds had more than just the EGR tube. If it does then you have A.I.R.

Do the tune one way or another! Most companies have free retunes for when you upgrade.

Is that ebay distributor really a good option? $45 looks a little scary

 

[TylerZ281500]

id upgrade gears if you want more towing ability

 

[Constantine]

Pasting this here so I can find it later.

http://www.crankshaftcoalition.com/wiki/Vortec_L31_cylinder_head

 

[Constantine]

You must be registered for see images attach

You must be registered for see images attach

OK so researching and talking to comp cams has me in a split between the k08-300-8 cam kit and the k08-302-8, either will use 1417-16 rockers (1.52 stamped self aligning)

The -300 doesn't require a tune and operates in 1000-5000 which is good for me, the lower it starts making power the better.
Has lobe sep. Of 112 and lift with the rockers is 450 in 480 ex.


The -302 requires a tune, which is fine with me as well and affordable, too.

But the down fall us an operating range of 1200-5200.
Lift with rockers is 480 in 480 ex. Lobe sep. OF 112 as well.

I'm not sure if the 200 rpm difference will be noticeable?

Will have threaded studs installed,
Pacesetter 2262 headers,
Shop installed 2.5" exhaust with converters from collector back,
Flowmasters (not sure which yet, have delta 44's now)
Delphi mpfi upgrade,
CAI but not sure which one.

Oh and stock ignition at least for the time being, research has me undecided about the longevity of aftermarket parts.

 

[TylerZ281500]

ill keep reading but heres my inital thoughts before looking at that picture. and lt1 fbody has a 1600 stall, a 4.3 s10 has about 1900 which is a looser converter, stock should be ok but the fbody one may help the overall feel and function of it, im told the ebay dizzys are ok, i was gonna lookinto it as my friends truck has been splitting the plstic casing in his regardless of brand, so yes stock should be fine.

roller tip stamped rockers arent gonna benefit you much besides noise, theres no lessening of resistance, only way to do that is go full roller, and im not one to talk i have stamped 1.6;s on my tbi truck right now only benefit they gave me was the different valve train angle.

if you research flowmaster is one of the poorest flowing exhausts out there, most people like it for the sound, im very vocal and hate flowmaster so i enjoy telling people its crap =) (im sorry for not being a nice person but i am a nice person overall if you knew me)

Pacesetters long tubes should sorta depend on what cam you go with, long tubes are gonna kill some of your low end power so for DD purpose it wouldnt be as beneficial id go with a mid length.

Mpfi Upgrade hell yes, iid definitely go with a tune with all this it would benefit you as would a 411 PCM swap for tuning purposes.

Volant makes the best true CAI for a vortec truck.

lastly your cam selection, breifly seeing them heres my thoughts, .480 lift is cuttin git close to max range of stock press in studs, so in light of that either pin them if you want to be cheap, or if your gonna build it proper your heads are gonna need to be magnafluxed anyhow so some screw in studs and LS2/6 springs with comp retainers would do your well with room to grow, as said you can run a stall converter with the larger cam and itll react fine, a trans cooler is recomended if you dont already have one. and imone to tune anything i modify engine internals so if it were me id be tuning both cams, i started tuning tbi for myself and very close friends DD's and such and going from a decent running truck with cam exhaust etc to a truck with the same stuff but has an extra few mpgs' , better pwoer and torque curves, idles smoother etc ive never turned back and not tuned something.

also with your exhaust, what are your plans? 2.5 " is just about damn perfect for these trucks, id go with an x or an h pipe to get everything you can out of your setup.

 

[Constantine]

ill keep reading but heres my inital thoughts before looking at that picture. and lt1 fbody has a 1600 stall, a 4.3 s10 has about 1900 which is a looser converter, stock should be ok but the fbody one may help the overall feel and function of it, im told the ebay dizzys are ok, i was gonna lookinto it as my friends truck has been splitting the plstic casing in his regardless of brand, so yes stock should be fine.

roller tip stamped rockers arent gonna benefit you much besides noise, theres no lessening of resistance, only way to do that is go full roller, and im not one to talk i have stamped 1.6;s on my tbi truck right now only benefit they gave me was the different valve train angle.

if you research flowmaster is one of the poorest flowing exhausts out there, most people like it for the sound, im very vocal and hate flowmaster so i enjoy telling people its crap =) (im sorry for not being a nice person but i am a nice person overall if you knew me)

Pacesetters long tubes should sorta depend on what cam you go with, long tubes are gonna kill some of your low end power so for DD purpose it wouldnt be as beneficial id go with a mid length.

Mpfi Upgrade hell yes, iid definitely go with a tune with all this it would benefit you as would a 411 PCM swap for tuning purposes.

Volant makes the best true CAI for a vortec truck.

lastly your cam selection, breifly seeing them heres my thoughts, .480 lift is cuttin git close to max range of stock press in studs, so in light of that either pin them if you want to be cheap, or if your gonna build it proper your heads are gonna need to be magnafluxed anyhow so some screw in studs and LS2/6 springs with comp retainers would do your well with room to grow, as said you can run a stall converter with the larger cam and itll react fine, a trans cooler is recomended if you dont already have one. and imone to tune anything i modify engine internals so if it were me id be tuning both cams, i started tuning tbi for myself and very close friends DD's and such and going from a decent running truck with cam exhaust etc to a truck with the same stuff but has an extra few mpgs' , better pwoer and torque curves, idles smoother etc ive never turned back and not tuned something.

also with your exhaust, what are your plans? 2.5 " is just about damn perfect for these trucks, id go with an x or an h pipe to get everything you can out of your setup.

I had edited my post to include other details after I initially posted the cam specs, seems it did not take when I came back so here is a repost:

OK so researching and talking to comp cams has me in a split between the k08-300-8 cam kit and the k08-302-8, either will use 1417-16 rockers (1.52 stamped self aligning)

The -300 doesn't require a tune and operates in 1000-5000 which is good for me, the lower it starts making power the better.
Has lobe sep. Of 112 and lift with the rockers is 450 in 480 ex.


The -302 requires a tune, which is fine with me as well and affordable, too.

But the down fall us an operating range of 1200-5200.
Lift with rockers is 480 in 480 ex. Lobe sep. OF 112 as well.

I'm not sure if the 200 rpm difference will be noticeable?

Will have threaded studs installed,
Pacesetter 2262 headers,
Shop installed 2.5" exhaust with converters from collector back,
Flowmasters (not sure which yet, have delta 44's now)
Delphi mpfi upgrade,
CAI but not sure which one.

Oh and stock ignition at least for the time being, research has me undecided about the longevity of aftermarket parts.