Many of you have been following along my previous threads discussing the issues I have been having with my built 347.
To sum up, it was burning oil from 2 cylinders. The plugs in those cylinders would foul within 30 miles.
I got to the bottom of it tonight. Ran a compression check...was perfectly fine. Did a quick leak down test by spraying air into the chamber and did not hear it in the pan. I was actually happy at this point and was hoping it was something in the head.
Got the head off, and those cylinders have DEEP gouges running vertically the entire bore. When you feel the bore, it feels like you are reading brail. The other 6 cylinders feel great by comparison. I am already running slightly overbored at 3.905. The max you can bore an LS1 is for 3.908 pistons so I am pretty sure this block is screwed and cannot be saved but maybe you guys have a better idea.
Looks like I am smurfed. Andrew gave me a deal on that block since he is a friend at only $300. No way I will find another that cheap. I know the machine shop will try to avoid liability since it is now more than just a simple rehone and rering (they said they would cover that on their dime based on our previous discussion before we knew exactly what was wrong).
It is now a $600-800 dollar mistake....I only paid them $1800 for this job.
In b4 Mike ends up paying over 5Gs for a simple forged 347.
CURSE ME FOR NOT DRIVING THE 200 MILES TO ANDY. That would have been a minor inconvenience but it would have been done right. Yay I am now a cautionary tale. Learn from my mistake...go to only people you know and trust.
No longer wanting to light the car on fire
Not a bad idea on the iron block, but I don't think they make 5.7 iron blocks do they?
Lots of iron 5.7 motors running around, especially in trucks. What they do is take a iron 5.3 block and bore it out to LS1 size and use a LS1 rotating assembly. Thompson Motorsports is a good example of a machine shop that does this, they sell various assembled short blocks (one for less than $2k with forged pistons). They also sell assembled iron 370 short blocks with regular pistons or forged. TMS has a good reputation over at LS1Tech.
2004 torrid red with red interior A4 GTO (1 of 499)
"It's a well know fact that after you hit 400 HP you have to go with split dual exhaust like the LS2 GTOs. The '04s could get away
with single side because they were only 350 HP. With 400 HP and beyond the car wants to turn right at WOT from the thrust."
But moreover junkyard iron LQ9 blocks are el-cheapo and might be an option.
Used to be that way before the word got out on what a great deal they were, but not so much anymore. I haven't been able to locate a LQ4/9 block within reasonable distance of me that wasn't >= $800, and I don't consider $800 el cheapo.
Shaking/vibrating/rattling more is actually a bonus to me. I enjoy the Parkinsons effect at a stop light while the car belches out fumes of unburnt fuel from its monster lopey overlap. To me, thats muscle car.
Maybe consider just sticking a 5.3 or a 4.8 in there? You can get a very nice build within your power goals with one of those motors. They're also kind of throw-away motors in the sense that if you blow it up, you can buy a complete long block for less than it would cost to fix the damaged one.
Especially with the longer rods of the 4.8, you can have a very stout bottom end with just ARP rod bolts being the only upgrade. My sister's boyfriend has a 5.3-swapped Chevelle that had about 130,000 miles on it BEFORE he started pushing 8 PSI through it. Motor is still going strong. He has another one sitting on a stand ready to go in when that one blows up.
That's not a bad idea. You wanted to boost your car eventually anyway right? Grab a 5.3 block, build it and boost the hell out of it. Certainly much cheaper to replace the block in case the next engine builder sucks too.
I know of a good shop but it's sort of far away from you. It's a one man show up in boyertown, pa.
As for the idea of throwing a 5.3 in, I have $3400 into this motor already. What happens to that? I need to try to salvage this as I am already heavily invested. I am meeting with the builder tomorrow morning to give him the news, I am crossing my fingers he stands by his work.
Knitting is a great idea LOL. I already retired from drag racing...the only times my cars have ever had issues either broke directly at the track, or shortly after. The GTO was 10,000 miles on the cam with no signs of any issues. Broke the rear then shortly after it had lifter issues. The vette had almost 25k miles with zero issues. Took it to the track, popped the piston then shortly after popped the tranny.
I am retiring my daily drivers from ever seeing the track. If I ever want to go again, I am building a dedicated car for it.
I see what you are talking about. Texas Speed does say this:
The TSP Street Racer 347 short-block will use a new GM Gen-III, LS1-style 5.3L aluminum block that is bored to 3.903".
Presumably, that's a mistake, because I found numerous other references to state otherwise:
5.3L truck: The cast iron blocks have thick walls so they can be bored up from the 4.8L/5.3L standard bore of 3.779" to 3.893" to make them into a 5.7L standard bore block if the additional weight of the iron block isn't an issue, but the aluminum blocks shouldn't be bored over .010" according to GM.
There seems to be conflicting info on LS1 Tech, although a couple people over there claim to have done it.
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