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first post...h3 ls swap...wanna follow?

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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
Hello to all, first post of what will most likely be many…Back in may I blew chunks out the side and bottom of my h3 I5 and have since gone off the dive at the deep end, deeply committed in dropping a 6L ls2 in its place. So far things have been very slow…very little info on this swap…will be posting pics and such going forward…may request a pic or two from some alpha owners from time to time. Got the hummer on the rack and parts all over place, See how things go...
 
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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
will post pics this week of the mess so far...got a drop out 04 6.0 ls2 on the stand getting a good look'n at it. current performance is building the harness now and programing also using their mounts. junkyard trailblazzer ss ecm and releated modules. new alpha oil pan, long input shaft and bell housing going to reuse the 4l60. I'll detail everything and start a build thread soon. stuck on the exhaust though...going to try shorties and make some "off road only" down pipes but theres just not a real good way to get the left side over theres stuff block'n every which way. Hince the need for some alpha pics. From what I can tell smashed pipe and a different cross member is how its down from the factory but I sure don't wanna buy that rather pricy factory cat/down pipe unless I really have to. till next....
 
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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
p.s. a picture of the alpha firewall would be great as well. theres a lip that seams to be an issue with the truck intake...seen BFHM done before to get around that but I'm going to try and keep the hammer in the tool bag for this one.
 
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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
p.s. a picture of the alpha firewall would be great as well. theres a lip that seams to be an issue with the truck intake...seen BFHM done before to get around that but I'm going to try and keep the hammer in the tool bag for this one.
 
SuperBuickGuy

SuperBuickGuy

Well-Known Member
Messages
3,403
Location
Woodinville, WA
exhaust, stock alpha pictures


LS shorty headers from a 5.3L 2003 Avalanche (you'll find that a lot of Avalanche stuff fits... not this, though)




that gives you an idea, all of these pictures and more are on my build thread (H3 SAR)... the avalanche headers don't work on either side because they're too wide, but the worst of the problems is the passenger side next to the starter... driver's side wouldn't be hard to make fit with a pie cut and reweld at the right angle... the passenger side would simply need a complete rework.
 
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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
Long story short…yes all factory functionality will be there but what I’m going to be running is a cluster f#%@ of modules, programing and custom harnesses. (mostly trailblazer SS). Current performance is building the harness and doing the factory programing. I’ll detail it all in the build thread that I’m going to start here very soon.
 
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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
superbuick you got any pics near the y pipe and the cross over near that cross member just at the top of the first photo?? that is what i'm looking for. got some shorties in the garage i'm going to test fit with know there bowtie but not sure exactly what they came from...we'll see what gives there here in a week or two....
 

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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
test fitted yesterday and all is well so far...no issues with fitment at all other than the factory manifold on the drivers side hits the engine mount will need to trim it a bit...no issues with the truck intake hitting the firewall and it looks like there will be room to clear the frame rail on the drivers side for a "off road only" down pipe...I still need to start a real build thread but I got to sort at least a hundred photos first....engines back out now...ordered a set of 799 heads and trading a buddy for a factory vette cam he had collecting dust. Soon she'll be all cleaned up and ready to dropped in for good.
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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
Thanks super-b for the pics!!! it looks like the cross member of the alphas got a notch that is not in the older h3s like mine...there is stuff in the way every direction going to have to get creative...can only smash, twist and loop-de-lu the pipe down so much...my goodwrench bud is like "so, whatcha think about some side pipes?" maybe better fitted on a 71 GS stage2 (wishin I had one of them to put side pipes on) ...then one would think that if this is to be the ultimate off roader the pipes should go strait up and out the hood...deep creekin style. going to try fitting some short tube headers that are from a 4x4 p/u once the motor and tranny are ready to go back in and see how they fit seeing as the truck manifolds are looking like a fit. we'll see...
 
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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
nice!! my dad bought a 71 skylark base new and I loved that car when I was a kid...sold it when I turned 16 after he found out how much his insurance was going to sky rocket. Ended up with a rusty pos 2 door 81 jetta instead kept his insurance bill within reason I guess. Back from vacation now so should be making some progress this week on the swap...still waiting for the harness and the modules (ecm,bcm & tcm) to get back from the programer...taking forever...got to rape a torque converter out of anouther truck to use (blazer 4.3) higher stall than the h3 factory...friend bought it for his truck like 3 months ago now wants to go aftermarket so worked out a deal with him for it...so far looking pretty good to have this finished up for around 5k....depending on the exhaust.
 
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rocketgti

Active Member
Messages
25
Location
pataskala, ohio
hadn't added to this in awhile had a drinking related accident and left me on light duty for awhile...got the h3 back in my buds garage this week and have started back working on it again. Heads are to be back from shop next week...found 799 cast vin b on car-parts.com for 350 to the door...had no major issues but are having them beaded, decked and a good valve job. Engine will be going in this week...harness and such back from current performance took a while first and second junk yard ecms I sent to them were locked out...ended up buying a new one on amazon for $200...leason learned just by a new one. purchaced alpha steering lines and a/c lines and we have rerouted the fuel lines...will have pics coming soon things are moving along now...
 
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Hunner

Hunner

Well-Known Member
Messages
2,334
Location
Arkansas
If I recall correctly, can't find the article, but I believe the frame was spread and the firewall was moved back when they (GM) installed the V8.

That may be why you are finding some space limitations.
Good luck, interesting to see your solutions to fitment.
 
Cyouincourt007

Cyouincourt007

Pavement Prince
Messages
542
Location
Miami,Fl
rocketgti said:
hadn't added to this in awhile had a drinking related accident and left me on light duty for awhile...got the h3 back in my buds garage this week and have started back working on it again. Heads are to be back from shop next week...found 799 cast vin b on car-parts.com for 350 to the door...had no major issues but are having them beaded, decked and a good valve job. Engine will be going in this week...harness and such back from current performance took a while first and second junk yard ecms I sent to them were locked out...ended up buying a new one on amazon for $200...leason learned just by a new one. purchaced alpha steering lines and a/c lines and we have rerouted the fuel lines...will have pics coming soon things are moving along now...
Click to expand...

What ever happened..any update?
 
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