More horsepower

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squaredeal91

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@SquareRoot I'm not a fan of ls swaps but I admire your tenacity,thus the like. Now who ever said tbi is real forgiving on cam selection,no they are not. Tbi is manifold pressure controlled,anything that effects vacuum is going to mess with your tbi. If you run much cam at all you will need a chip burned.
It was me
 

SubDominant

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Hi junior.
Got a timing light?
Try more ignition advance, that's what you're after. Save your funds for new parts and buy an advance light. Digital with buttons or get one with a dial. Stock setting is 0° I think. My truck is running at 9.5 in Oklahoma. (Digital light is win)

A K&N air filter won't cure what ails you. More ignition advance is a step in the right direction though.

If you throw away the stock muffler and replace it with a Dynomax Super Turbo at the same time you will then have a bonafide hotrod. Ask anybody.
I did a gear swap. 3.73 to 4.56 on 33" tires (may potentially go to 35's). Yes, more zoom off the line but still slow.

Advanced the timing to 9 degrees. Now its moving even better! Way better. Not a race car but I love it now.
 

Rusty Nail

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It's AWESOME you love it now but there is so much more.. in store.
That's likely gonna be your sweet spot...9°... in my experience you are blocked up in the cylinder heads now.

I do not believe vortex geads are a cost effective go-to at entry level. I bought #083 castings (TPI 64cc) for my engine and stick at that is probably the best flowing cast iron SBC head ever made. At the very least buy what they call "z-28" valvesprings and a "fluff and buff" porting to nuke the casting flash and the high spots...add Manley 1.94 intake 1.60 exhaust valves and a "3 angle valve job".
If you are running a #191 or #193 (76cc) swirl port cylinder heads it's a world of difference for a few hunnert bucks..1.6 comp cams roller tips are serious bang for the buck and i also condone the use of "copper shim" head gasket to gnash even more squeeze out of your dished pistons!
AND THEN?!

and then the next thing you know your engine will be exxxtra rumbeldy all brapp! brapp! brapp! like it's a flippin top fuel dragster except you'll be runnin pinché 87.
Like a G.
All S.B.C.

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But hey mannn, don't take my word for it, go prove it to yourself. Now you've got 4.56 youll actually be going fast - if it's got 1.5" headers.
..reality is now your heads are killin the high rpm power.

Dude that is the recipe for bolt on SBC power with a stock short block.

You can do it!
Swap the heads dude.
 
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SubDominant

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It's AWESOME you love it now but there is so much more.. in store.
That's likely gonna be your sweet spot...9°... in my experience you are blocked up in the cylinder heads now.

I do not believe vortex geads are a cost effective go-to at entry level. I bought #083 castings (TPI 64cc) for my engine and stick at that is probably the best flowing cast iron SBC head ever made. At the very least buy what they call "z-28" valvesprings and a "fluff and buff" porting to nuke the casting flash and the high spots...add Manley 1.94 intake 1.60 exhaust valves and a "3 angle valve job".
If you are running a #191 or #193 (76cc) swirl port cylinder heads it's a world of difference for a few hunnert bucks..1.6 comp cams roller tips are serious bang for the buck and i also condone the use of "copper shim" head gasket to gnash even more squeeze out of your dished pistons!
AND THEN?!

and then the next thing you know your engine will be exxxtra rumbeldy all brapp! brapp! brapp! like it's a flippin top fuel dragster except you'll be runnin pinché 87.
Like a G.
All S.B.C.

xc_hide_links_from_guests_guests_error_hide_media

But hey mannn, don't take my word for it, go prove it to yourself. Now you've got 4.56 youll actually be going fast - if it's got 1.5" headers.
..reality is now your heads are killin the high rpm power.

Dude that is the recipe for bolt on SBC power with a stock short block.

You can do it!
Swap the heads dude.
I think I am moving in that direction! I blew my 76cc's on a 118* day trip from Cali to AZ (think they was blown when I bought the truck). Stinking thing made it all the way and then hydro-locked in my driveway!! But I was just looking for some used replacements and was not sure about the bottom end so I found a set of used 64cc heads. I think they are tbi heads that someone tried to make into race heads and found out did not work. They are ported and had valves done and springs. I got em for $100 bucks so I slapped them on. This was a few years ago and I am still running them. Think they are 193 castings so maybe 65cc's. Yeah... no top end. But better than the original 76's.

I will keep my eye out for some of them 083's your are talking about and maybe swap em out.

I may just try some 1.6 rockers now.

Got shorty headers already.
 

Rusty Nail

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Some of the best realization in aftermarket rocked arms is found after the lift of each valve becomes the same.
Factory tolerance was not the greatest control ever. Ensuring uniformity will realize its' own gains, not giving mention to increased lift and improved flow. Your current factory 16 rockers allow for a LOT of variation across the engine and between each cylinder. In reality, Uniformity is vital.

These are a common, popular choice.
Be advised other weak links may become apparent after installation. It's hard to go wrong and you will probably have to buy new valve covers.
Installation can certainly open other doors but getting them settled is certainly a necessary step in the right direction and can be fun...your engine will thank you for tossing the stamped steel units, for certain... it will become a different animal - after all the valves lift the same. That is difficult to overstate.
 

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SubDominant

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Some of the best realization in aftermarket rocked arms is found after the lift of each valve becomes the same.
The factory tolerance was not the greatest control ever. Ensuring uniformity will realize its' own gains, not giving mention to increased lift and improved flow. Your current factory16 valves allow for a LOT of variation across the engine and between each cylinder. Uniformity is vital.

These are a common, popular choice.
Be advised other weak links may become apparent after installation. It's hard to go wrong and you will probably have to buy new valve covers.
Installation can certainly open other doors but getting them settled is certainly a necessary step in the right direction and can be fun...your engine will thank you for tossing the stamped steel units, for certain... it will become a different animal - after all the valves lift the same. That is difficult to over state.
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Good food for thought... and action!

I failed to mention I also have added a TB spacer and pod spacer. Both worth it to me.

Little gains add up.
 

vr1967

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May also want to swap fuel pumps. The ep386 (tbi) pump only flows about 75 lph where the ep381 (96-97 Vortec) pump flows about 155 lph.
It definitely makes a difference in the 7.4/454 tbi trucks, which always were fuel starved.

What color spring do you have in the tbi regulator?
 

SubDominant

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May also want to swap fuel pumps. The ep386 (tbi) pump only flows about 75 lph where the ep381 (96-97 Vortec) pump flows about 155 lph.
It definitely makes a difference in the 7.4/454 tbi trucks, which always were fuel starved.

What color spring do you have in the tbi regulator?
You know, I rebuilt the TB a couple years ago and don't remember the color of the spring. I have the Vortec fuel pump on my wish list.
 

Rusty Nail

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Later on I thought about self-aligning rocker arms and changed the picture to reflect a different part number that is likely more correct for your application.
 

SubDominant

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Later on I thought about self-aligning rocker arms and changed the picture to reflect a different part number that is likely more correct for your application.
So you are taking my current heads into account? I hope so. I am not sure I will be making a change like that soon. So a 1.5 ratio rocker arms, but rollers.

I had to study and build up the courage to do my gears myself. Turned out to be such a fulfilling endeavor. Gave me a sense of pride. Saved me a bunch of dough, so, I am much more willing to try things now.
 

Rusty Nail

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Adjusting rocker arms will be the same.

I only assume you run factory TBI heads, 091 or 093 likely with the swirl ports.
Those do in fact require the self aligning type or rocker which is why i changed the picture, the answer to your question is yes. Those rockers are also required for an 083 head, so they would transfer if necessary.

To be very clear - the main benefit of running after market rocker arms is uniformity. The allowed variance found in the factory units will make you puke. All of the factory rockers do NOT lift the same. You will always have certain cylinders stronger or weaker than the others. Rather you choose a full roller or a roller tip rocker, aftermarket parts will be superior because the quality control is better. The Comp Cams are cheap , strong, and very popular but you could spend a BUNCH more on 16 rocker arms if you want to.They will all be the same. Again, it's difficult to overstate.
Not like a 1.52 is a huge gain over a 1.5, but you can probably install those without opening too big a can of valvetrain woes like coil bind and new pushrods. They are pretty much bolt on spare whatever fun changing the valvecovers has to offer. Cuz there will be some...no doubt. Like bending your AC lines and finding a place for the various valve cover mounted sensors that will lose their brackets. Needing longer vacuum lines, etc. ... All part of the fun. Totally worth it and a necessity of truly hauling ass and roller tips really help it run smoother.

Like you said, the little changes really add up but changing rocker arms is kind of a big deal like rebuilding a differential but not really. It will make a huge change though.

You can do it alright and you might as well change those first so you can get that mod settled in good and proper.. it'll take a while.
AND THEN you can think about changing the heads if you wanna. New rockers will not get rid of the ramp in your intake ports however. By the time you ported on a pair of swirlport heads to "fix" them, if you could? you coulda bought better heads for cheaper. TPI 083s will flow just as good as a vortex head and putting those on is WAY cheaper than the headaches associated with cathedral heads. That's my opinion - somebody else has a different one.
Cylinder head porting is sold by the hour and the sky is the limit.

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SubDominant

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Adjusting rocker arms will be the same.

I only assume you run factory TBI heads, 091 or 093 likely with the swirl ports.
Those do in fact require the self aligning type or rocker which is why i changed the picture, the answer to your question is yes. Those rockers are also required for an 083 head, so they would transfer if necessary.

To be very clear - the main benefit of running after market rocker arms is uniformity. The allowed variance found in the factory units will make you puke. All of the factory rockers do NOT lift the same. You will always have certain cylinders stronger or weaker than the others. Rather you choose a full roller or a roller tip rocker, aftermarket parts will be superior because the quality control is better. The Comp Cams are cheap , strong, and very popular but you could spend a BUNCH more on 16 rocker arms if you want to.They will all be the same. Again, it's difficult to overstate.
Not like a 1.52 is a huge gain over a 1.5, but you can probably install those without opening too big a can of valvetrain woes like coil bind and new pushrods. They are pretty much bolt on spare whatever fun changing the valvecovers has to offer. Cuz there will be some...no doubt. Like bending your AC lines and finding a place for the various valve cover mounted sensors that will lose their brackets. Needing longer vacuum lines, etc. ... All part of the fun. Totally worth it and a necessity of truly hauling ass and roller tips really help it run smoother.

Like you said, the little changes really add up but changing rocker arms is kind of a big deal like rebuilding a differential but not really. It will make a huge change though.

You can do it alright and you might as well change those first so you can get that mod settled in good and proper.. it'll take a while.
AND THEN you can think about changing the heads if you wanna. New rockers will not get rid of the ramp in your intake ports however. By the time you ported on a pair of swirlport heads to "fix" them, if you could? you coulda bought better heads for cheaper. TPI 083s will flow just as good as a vortex head and putting those on is WAY cheaper than the headaches associated with cathedral heads. That's my opinion - somebody else has a different one.
Cylinder head porting is sold by the hour and the sky is the limit.

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Pretty sure whoever I got the heads from tried to build a race motor with these heads. They are 14102193 if I remember correctly and definitely have beehive or some type of race springs installed. I wonder if they would handle 1.6 rr's if I upgrade my stock pushrods?
 

Rusty Nail

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Don't you think it's weird there are 30,000 members of this board but nobody else has any input?
Ever heard of the Dead Internet Theory?

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