4.3 performance upgrade
#11
12-27-2018, 01:34 PM
I'll be finishing it up sometime in January, so I'll be sure to make a nice how to once Its all set.
heres the wiring solution thanks to a member on a different forum:
You will need to cut the injector harness off at the connector.
There are 12 wires total.
ALL Pinks are 12volts with Ignition on. (hot)
All the other wires are grounded by the ECM.
You will need injector connectors for your stye or choice of Injector.(6)
Wiring is as follows:
(Letters are on the stock injector connector)*see picture below*
#1 injector: (E) Pink and (F) Black
#2 injector: (H) Pink and (G) Green/Black
#3 injector: (D) Pink and (C) Pink/Black
#4 injector: (J) Pink and (K) Light blue/Black
#5 injector: (B) Pink and (A) Black/White
#6 injector: (L) Pink and (M) Yellow/Black
Please take the time to solder your connetions and shrink wrap. Make sure your wires are long enough to go to each injector.
This is the only wiring you'll have to do on the entire project. Cool !!!
heres the wiring solution thanks to a member on a different forum:
You will need to cut the injector harness off at the connector.
There are 12 wires total.
ALL Pinks are 12volts with Ignition on. (hot)
All the other wires are grounded by the ECM.
You will need injector connectors for your stye or choice of Injector.(6)
Wiring is as follows:
(Letters are on the stock injector connector)*see picture below*
#1 injector: (E) Pink and (F) Black
#2 injector: (H) Pink and (G) Green/Black
#3 injector: (D) Pink and (C) Pink/Black
#4 injector: (J) Pink and (K) Light blue/Black
#5 injector: (B) Pink and (A) Black/White
#6 injector: (L) Pink and (M) Yellow/Black
Please take the time to solder your connetions and shrink wrap. Make sure your wires are long enough to go to each injector.
This is the only wiring you'll have to do on the entire project. Cool !!!
#13
03-12-2019, 04:31 PM
I am exactly in the same place as you. Although would love a V8 swap, it just doesn't fit the budget at this time. I did a V8 swap into a volvo 15 years ago, and the price to do it right was crazy.
i would like to keep my 4.3L build around the $3000 range.
Biggest problem I see is that our current fuel injection system really cant produce much more air/fuel volume being pushed through the engine. Keeping in mind an engine is nothing but a giant air pump.
I have gone over multiple scenarios that include a bigger cam kit with springs. Bore the Block .030 over with new pistons. Shave the deck and heads to produce a little higher compression. Perhaps find a marine intake with the fuel rails so I can increase injector size. Our ECU from what I read, will still be the limiting factor. Our stock exhaust system seems to be a great flowing system. Maybe some head porting, although I can't find any solid facts that it is worth it on these particular heads, I need to research that more.
The only other alternative for me is to put a Jasper or ATK crate motor in and find a used supercharger system on it with a dialed down PSI.
Thoughts?
i would like to keep my 4.3L build around the $3000 range.
Biggest problem I see is that our current fuel injection system really cant produce much more air/fuel volume being pushed through the engine. Keeping in mind an engine is nothing but a giant air pump.
I have gone over multiple scenarios that include a bigger cam kit with springs. Bore the Block .030 over with new pistons. Shave the deck and heads to produce a little higher compression. Perhaps find a marine intake with the fuel rails so I can increase injector size. Our ECU from what I read, will still be the limiting factor. Our stock exhaust system seems to be a great flowing system. Maybe some head porting, although I can't find any solid facts that it is worth it on these particular heads, I need to research that more.
The only other alternative for me is to put a Jasper or ATK crate motor in and find a used supercharger system on it with a dialed down PSI.
Thoughts?
Zero deck block
0.041 thick head gasket
SKB193L-030 12cc dish Pistons (1.560 compression height)
20560720LK Lunati Cam & Lifters (this is a balance shaft engine)
Use the stock 64cc Vortec heads with guides machined for high lift.
Stock exhaust manifolds (headers won't be worth it and the leaking SOBs won't play nice with O2 sensors))
Talk to Lunati, you may need to go to an adjustable rocker setup (but maybe not).
This will give you a 9.5:1 engine, with 8.0:1 dynamic compression at sea level (intake closes at 57° ABDC) and excellent quench (0.041) to combat detonation.
113 LCA will keep the fuel injection happy and the idle smooth.
Marine intake w/higher flow injectors to feed enough fuel for the extra power.
Professional tune
I would expect somewhere around 1 hp per cube like the Ramjet GM performance engine and I bet it will still pass emissions.
.
Last edited by LesMyer; 03-12-2019 at 04:36 PM.
#14
03-13-2019, 08:04 AM
At this point with the little bit of research I have done, I think I am going to do a budget build like back in the day.
Refresh block assembly
Refresh heads with a descent valve job and cleaned up ports
Undecided on cam at this time. Only know I want it to perform at the daily driver level with optimum performance around the 3000 RPM range. (Input here would be greatly appreciated) Not looking for top end here, got a Camaro for that. Just want to be able to bust through rush hour traffic.
Marine Intake (getting hard to find but think the guys at Michigan Motors are locating one for me with mechanical linkage). Gasket match. Undecided about injectors, hoping to use the ones that come with the intake.
Custom exhaust with stock manifolds
Electric fans
Tune
Motor has to be built, pouring oil out of rear main and timing cover. If I can get an extra 30/40 ponies in the range I am looking for I will be happy.
Am I being realistic or no.
Refresh block assembly
Refresh heads with a descent valve job and cleaned up ports
Undecided on cam at this time. Only know I want it to perform at the daily driver level with optimum performance around the 3000 RPM range. (Input here would be greatly appreciated) Not looking for top end here, got a Camaro for that. Just want to be able to bust through rush hour traffic.
Marine Intake (getting hard to find but think the guys at Michigan Motors are locating one for me with mechanical linkage). Gasket match. Undecided about injectors, hoping to use the ones that come with the intake.
Custom exhaust with stock manifolds
Electric fans
Tune
Motor has to be built, pouring oil out of rear main and timing cover. If I can get an extra 30/40 ponies in the range I am looking for I will be happy.
Am I being realistic or no.
#15
03-13-2019, 12:14 PM
https://www.powerperformancenews.com/tech/the-missing-link-v6-cam-test/
Power @ 3000 with the bigger cam was about the same. Less when below 3000 rpm. 2002 balance shaft 4.3 made 251hp vs 207hp, Comp 280 vs stock cam, using a carb for both.
Power @ 3000 with the bigger cam was about the same. Less when below 3000 rpm. 2002 balance shaft 4.3 made 251hp vs 207hp, Comp 280 vs stock cam, using a carb for both.
Last edited by LesMyer; 03-13-2019 at 12:17 PM.
#16
03-13-2019, 12:36 PM
https://www.powerperformancenews.com/tech/the-missing-link-v6-cam-test/
Power @ 3000 with the bigger cam was about the same. Less when below 3000 rpm. 2002 balance shaft 4.3 made 251hp vs 207hp, Comp 280 vs stock cam, using a carb for both.
Power @ 3000 with the bigger cam was about the same. Less when below 3000 rpm. 2002 balance shaft 4.3 made 251hp vs 207hp, Comp 280 vs stock cam, using a carb for both.
I have decided to go with the 5.3 V8 swap. Sourcing one from a 2006 Yukon with low miles. I'll refresh it with rings, bearings, the basics. After an upgraded cam I should be able to get a very conservative 350 HP.
Have all my info for cooling system, motor mounts, wiring/computer system, oil pan, shorty headers, etc.
I'll do the conversion myself, except the exhaust.......getting pretty excited about it, can't wait to have a V8 Zr2 Blazer done correctly.
#17
03-13-2019, 01:40 PM
#18
05-16-2019, 11:44 AM
Going to back up and punt on this one I think. May have a marine intake up for sale soon. Just not ready to spend the funds for all the head work, pistons and so on. Cam choice is a tough one, therein lies my problem. Just not like the old days where you just popped a little bigger cam and intake and went on. You can tell how old I am when I say "back in the day" I could do headers, cam, intake and carb for a nice increase in HP for under $500.
#19
06-16-2019, 01:34 PM
It has a deeper meaning. You cannot get the answer of what parts (cams, pistons, connecting rods, fuel injection system or intake) to use, unless You know what build You're trying to do. I.e. aggressive cams and I type connecting rods are for higher max rpm You'll find in racers. Define what You want 1st.
