Tight budget performance mods. What do you think?

[GMTMark]

My 98 has the stock L31 with 162,000 mi and in excellent shape. Uses no oil; had mobil 1 most of its life and compression test is great. I’m thinking about upgrading to the newer spider, 0411, lightly ported heads w good springs and more lift capacity (heads are done) and a Bullett recommended cam. No mods to the short block for now. RPM range of 1500 to 5500. Does anybody here have better suggestions for the money? Can the same money be better spent for better performance? I plan to street/strip.

 

[RanchWelder]

The mileage would concern me.

Adding power to a bottom end without freshening up the lowers is asking for trouble.

The mod sequence I would recommend is a new oil pump, copper oil pump gasket, ARP oil pump bolts, replace the plastic oil pump connector rod end with a solid ARP steel pump to distro rod, fresh crank bearings and ARP Crank Bolts, not stretch to torque bolts like GM uses. Size and check the rods, lil' dingle berry, New Rings. Polish/file the oil pump gears before install.
New Seals... fresh bottom, then fresh top.

Know that is not what you asked...

The Jasper Marine I bought, came with brass freeze plugs and a Fuel Pump machined and tapped boss, in case I wanted to run a carb down the road. The GM casting was brand new from Mehico, machined at Jasper by the good old boys from Indiana. It also came with forged flat top pistons, Chevrolet Performance Crankshaft.

I cannot recommend Jasper enough, the way the engine turned out after what I thought was a nightmare.

Contact Jasper for stock heads or call a circle track engine builder/machine shop and buy good quality Vortec's or copies made from good quality castings. If you can possibly save your block as a backup build and afford the package Jasper sells, you'll be very glad you did, from my experience.

The racetrack head builders you'll find online from Indiana, Wisconsin and a few other states, have the secret sauce, however you'll only want the sauce on a good to very good bottom end, or you'll be back in there way too early and wast your money.

LTL shipping rates are about to freak out, so think it through quick before it becomes un-obtanium or outrageous to ship a block.

I have 2 sets of swirl port heads but you do not want them, really. If you were local... They are not worth the $85 each to ship them, is the problem. By the time you flux them and deck them and grind a 3 angle on them, all you have is swirl ports.
I guess you could try to find somebody here on the forum who is closer with similar low dollar heads, they don't want?

Good luck!

 

[GMTMark]

Thank you for the excellent advice. My heads are already done by a good friend that does circle track heads. He did all the checking and put in new guides, valves, studs, springs and guide plates. The heads were proven from another engine I ran before. I don’t have money for parts to do the short block or I would buy a balanced rotating assembly in 383ci. I should have said that I’ve built several engines for performance and your advice is correct. I’m retired and very little money so I might just run it bone stock until I can have enough money to do it right. Thanks.

 

[Schurkey]

My 98 has the stock L31 with 162,000 mi and in excellent shape. Uses no oil; had mobil 1 most of its life and compression test is great. I’m thinking about upgrading to the newer spider,

YES

0411,

Maybe. Only if you can tune the thing.

lightly ported heads w good springs and more lift capacity (heads are done)

You already own 'em. Might as well. But that wouldn't have been a high priority if you didn't have 'em already. Take care with selecting the head gaskets. Easy to get too-much piston-to-head clearance leading to lazy burn and lower compression ratio.

and a Bullett recommended cam.

Depending on the grind, only if you're able to tune the computer.

No mods to the short block for now. RPM range of 1500 to 5500. Does anybody here have better suggestions for the money? Can the same money be better spent for better performance? I plan to street/strip.

FIRST thing I'd have done is to improve the exhaust. If the small-block muffler is anything like the big-block muffler, it's hatefully restrictive.

Assure that the catalyst(s) aren't plugged or partially-plugged.

The Y-pipe may be restrictive. It is on the TBIs.

Fresh O2 sensors. They get lazy with age/miles.

Some folks on this site--that I generally trust--say that headers make a big difference. I did not notice much improvement with mine. Didn't hurt any, though.

 

[GMTMark]

YES


Maybe. Only if you can tune the thing.


You already own 'em. Might as well. But that wouldn't have been a high priority if you didn't have 'em already. Take care with selecting the head gaskets. Easy to get too-much piston-to-head clearance leading to lazy burn and lower compression ratio.


Depending on the grind, only if you're able to tune the computer.


FIRST thing I'd have done is to improve the exhaust. If the small-block muffler is anything like the big-block muffler, it's hatefully restrictive.

Assure that the catalyst(s) aren't plugged or partially-plugged.

The Y-pipe may be restrictive. It is on the TBIs.

Fresh O2 sensors. They get lazy with age/miles.

Some folks on this site--that I generally trust--say that headers make a big difference. I did not notice much improvement with mine. Didn't hurt any, though.

 

[GMTMark]

I forgot
to say that I have shorty headers, stainless. Not as good as long tubes but better than stock. Good thoughts about exhaust. I can tune the ecm since I have HPTuners and have used it a few times. Thanks.

 

[L31MaxExpress]

I like the Volant air intake system on the Vortec trucks. It makes a difference even on a stock truck. The MAP sensor reading does not drop off as much at WOT and the MAF reads higher airflow, both a solid indication that it in fact is allowing more airflow to the engine and more power.

 

[Erik the Awful]

I forgot to say that I have shorty headers, stainless. Not as good as long tubes but better than stock. Good thoughts about exhaust.

What does the rest of your exhaust consist of? Most people who buy shorties buy them because they bolt right in place of the stock manifolds, but they're limited if the rest of the exhaust system is garbage.

 

[GMTMark]

What does the rest of your exhaust consist of? Most people who buy shorties buy them because they bolt right in place of the stock manifolds, but they're limited if the rest of the exhaust system is garbage.

The cats are new stock from Walker and the rest is original. When I can afford it I’m thinking about a Flowmaster 2-in 2-out quiet muffler and duals. The planned exhaust could be better but I want quiet and something easy to return to stock.

 

[RanchWelder]

Cool. It sucks making tough descisions when you already know better.
So many of my projects are getting screwed up because the budget I had three years ago to build my truck is hitting the wall.

GMTMark good luck with your build.
It sounds like you already know what you are going to do...