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Some pics of my CNC ported LSA blower that I offer.....Im building a 416 CID engine now for a customer that I will be installing this blower on shortly and dyno testing at Westech
Moot point since we now know it's not a good idea. It's a dead end road....
I’d say it’s an interesting idea considering you can get a LT4 blower for a grand. It may not set any records on the dyno, but I think it would generate some interest for people looking for a budget supercharger set-up. Dropping $8,000+ for a Procharger may not make financial sense for most. I’d be happy to pay half that to get some blower whine and a modest boost in power - everything doesn’t need to be max effort.
I’d say it’s an interesting idea considering you can get a LT4 blower for a grand. It may not set any records on the dyno, but I think it would generate some interest for people looking for a budget supercharger set-up. Dropping $8,000+ for a Procharger may not make financial sense for most. I’d be happy to pay half that to get some blower whine and a modest boost in power - everything doesn’t need to be max effort.
You're dealing with heads that are a comparative compromise on any engine they're bolted to, as Tony stated above.
A crappy head isn't a reason to buy a cheaper blower.
Heck I’m just glad Tony showed up in here. The guy wasn’t going to believe me, that’s for sure. Lol!
I had the same problem like 15 years ago when I ported the inlet of my FAST 78 to 85MM and posted it up on here. Everyone was saying it was pointless and wouldn't work and that the 90MM was different internally... until Tony showed up and was like, "Nope. Only difference was the inlet size."
Heck I’m just glad Tony showed up in here. The guy wasn’t going to believe me, that’s for sure. Lol!
Well THE GUY brought up a topic that nobody had real knowledge on.
and is different. If you feel happy with discussing here the 20000000 Cam head combo questions then go ahead. at least now we know whats going on in the LT world.
however not even tony has commented on the CHEAP stuff option 5.3s with L83 heads. tony probably dont deal with them much and that is fine. i do since i am always on a budget and its ture hotrodding to use what you have. and i have those parts
DUSTYWS6 makes a great point for 90% of us, and that is not everything being built has to be a max effort, 6 second 1/4 miler. When I was 20 years old, I once built a 4 cylinder motorcycle engine that was running under the NHRA class record at the time. Before I could get it to a record meet, the record went lower than I could run (and afford!!). So I didn't bother. Right then I learned the no matter how fast you are, there'll be someone faster. Sebambam, you make a good point on using what you have. If you like doing a lot of modding, to get less than optimum results, and it's cheaper, I say go for it. If you end up with a low 11 second car@125mph 1/4 mile, for less $$$ than going for all LS stuff for a marginal gain, but more $$$, you engine, your decision. But I'm with Tony and the others who know these heads are second rate to the LS stuff. As I get older, I tend to try projects that are less labor intensive if the $$$ signs and performance are close going either way. Nobody will know what combo you have if all they see is your rear bumper....
Just my .02 but I think for a 5.3 or smaller bore that can't use the ls3 head(or rectangular port) this could be a pretty decent upgrade.... If you can use the LS3 or rectangular port head this wouldn't be worth it at all. The LS3 outflow the LT1 heads, the biggest thing giving the LT era of engines more power is more compression and added lift with a slightly larger cam. Don't get me wrong, I like how the LT1 runs, but the ls3 has more potential.
LT1 Tech Specs(460/465)
Part Number: 19328728
Engine Type: Direct Injection spark-ignition Gen-V Small-Block V-8
Displacement (cu. in.): 376 (6.2L)
Bore x Stroke (in.): 4.065 x 3.622 (103.25 x 92mm)
Block (P/N 12619171): Cast aluminum with 6-bolt nodular iron main bearing caps
Just my .02 but I think for a 5.3 or smaller bore that can't use the ls3 head(or rectangular port) this could be a pretty decent upgrade....
And that is the point i wanted to discuss.
STOCK for STOCK headswap
706 Stock for L83 Stock head on a 5.3 ( NO Stock Rec port heads available for that SBE.
At the risk of digging up a dead horse...
I'm a high school teacher building an engine with my students. I'm also in TX and 6.0's are like unicorns, but the local yard will give us a 5.3.
I picked up L83 heads for $100. We are going to give it a try. When I do the math, with the LT2 intake deal from Mast, I'm at less than $2k at full retail including heads, springs, cam, intake, fuel rails and injectors. This includes the stuff I need to make it work like the pushrods, DI plugs and machine shop services.
Seeing how my only goal is making 500 NA at the flywheel and the engine doesn't have to do anything else right now, I'm not sure there is a more cost effective way of doing this.
I'm sure I can get there with ported stock heads, cam, springs, aftermarket intake and fuel system, but it adds up to more, especially since I can't use grant funding to buy used parts.
Don't get me wrong, I understand the limitations. I don't think think this is going to be the next big thing. However, ugly flow is still flow and when you don't have the budget, suboptimal is better than nothing.
If anyone has a less expensive way to meet my goals that doesn't involve used or Chinese ebay parts, let me know.
At the risk of digging up a dead horse...
I'm a high school teacher building an engine with my students. I'm also in TX and 6.0's are like unicorns, but the local yard will give us a 5.3.
I picked up L83 heads for $100. We are going to give it a try. When I do the math, with the LT2 intake deal from Mast, I'm at less than $2k at full retail including heads, springs, cam, intake, fuel rails and injectors. This includes the stuff I need to make it work like the pushrods, DI plugs and machine shop services.
Seeing how my only goal is making 500 NA at the flywheel and the engine doesn't have to do anything else right now, I'm not sure there is a more cost effective way of doing this.
I'm sure I can get there with ported stock heads, cam, springs, aftermarket intake and fuel system, but it adds up to more, especially since I can't use grant funding to buy used parts.
Don't get me wrong, I understand the limitations. I don't think think this is going to be the next big thing. However, ugly flow is still flow and when you don't have the budget, suboptimal is better than nothing.
If anyone has a less expensive way to meet my goals that doesn't involve used or Chinese ebay parts, let me know.
243 heads with a bowl clean up could have easily gotten you there.....and you would have made mountains more torque and throttle response at the same time
Besides the fact Im really questioning whether the larger LT intake valves would clear that small bore (I dont think they will), that head is waaaaay too large for that little 5.3 engine.
The engine will be a complete turd till 4000 RPM's or more
Its just a bad combination.....you can do alot better for similar money or even less
Keep in mind I'm not trying to sell you anything....just offering some helpful advice
At the risk of digging up a dead horse...
I'm a high school teacher building an engine with my students. I'm also in TX and 6.0's are like unicorns, but the local yard will give us a 5.3.
I picked up L83 heads for $100. We are going to give it a try. When I do the math, with the LT2 intake deal from Mast, I'm at less than $2k at full retail including heads, springs, cam, intake, fuel rails and injectors. This includes the stuff I need to make it work like the pushrods, DI plugs and machine shop services.
Seeing how my only goal is making 500 NA at the flywheel and the engine doesn't have to do anything else right now, I'm not sure there is a more cost effective way of doing this.
I'm sure I can get there with ported stock heads, cam, springs, aftermarket intake and fuel system, but it adds up to more, especially since I can't use grant funding to buy used parts.
Don't get me wrong, I understand the limitations. I don't think think this is going to be the next big thing. However, ugly flow is still flow and when you don't have the budget, suboptimal is better than nothing.
If anyone has a less expensive way to meet my goals that doesn't involve used or Chinese ebay parts, let me know.
if your goal is 500 N/A at the flywheel, instead of spending $2k an on LT2 intake from mast, why not spend $1100 sending the heads to TSP for the PRC port job, then get a sponsor or what not to cut you a deal on a fast 102 intake manifodl? https://www.texas-speed.com/p-1172-p...-castings.aspx
any loss of compression on that 5.3 will kill you. since the 706/862 heads that came with it have the smallest combustion chamber, they are a great starting point.
243 heads with a bowl clean up could have easily gotten you there.....and you would have made mountains more torque and throttle response at the same time
Besides the fact Im really questioning whether the larger LT intake valves would clear that small bore (I dont think they will), that head is waaaaay too large for that little 5.3 engine.
The engine will be a complete turd till 4000 RPM's or more
Its just a bad combination.....you can do alot better for similar money or even less
Keep in mind I'm not trying to sell you anything....just offering some helpful advice
-Tony
The L83 heads are off the LT 5.3 with 1.930/1.556 valves, so clearing the bore shouldn't be a problem since the LS and LT 5.3s have the same 3.780 bore size. The heads do have large 248cc intake and 102cc exhaust ports, though. The combustion chambers are 58cc, so as long as the 5.3 has flattop pistons, compression should be a tick over 10.5:1. I'd probably look at milling the heads to get to 11-11.5:1.
I'd like to see a comparison between these L83s and ported 862s.
if your goal is 500 N/A at the flywheel, instead of spending $2k an on LT2 intake from mast, why not spend $1100 sending the heads to TSP for the PRC port job, then get a sponsor or what not to cut you a deal on a fast 102 intake manifodl? https://www.texas-speed.com/p-1172-p...-castings.aspx
any loss of compression on that 5.3 will kill you. since the 706/862 heads that came with it have the smallest combustion chamber, they are a great starting point.
What you suggest would undoubtedly work and result in a far better power curve. In fact, it was my original intent to use ported 706 heads and a Holley Hi-Ram (I like the idea of the kids being able to design and 3D print their own upper manifold to attach to the Holley base),
but I did the math a thousand times and couldn't make the money work.
I need heads, intake, workable fuel rails, injectors, cam and springs. With the L83 heads (smaller combustion chamber, not bigger) I'm $1700 all in on those parts including the supporting parts to make it work.
If I spend $2200+ on heads and and intake, I still need appropriate injectors, cam and springs, maybe $700-800. $3k plus shipping is significantly more than $1700.
I'm not stupid, just broke. My wife has cancer and hasn't worked in over a year. Being a high school teacher doesn't begin to cover the bills, so this summer, I'll need a second, second job.
If my life hadn't fallen off a cliff we wouldn't be having this conversation. The engine would be mine, built along the lines you describe and going into an '81 Mustang Cobra, but stuff happens.
As things are, this engine will likely never see a car in this configuration. It will go on the dyno and impress my students, grant committee and admin types with peak power numbers. That's the only job. We get the kids excited to learn science and math in order to build a better engine. The right people see their money being spent on some thing "impressive". It took lots of work on my part to get us this far, including winning two competitive grants. This is what it takes to get more for next year, you have to results to show and then more people will work with you.
Maybe we recycle the heads and intake for a turbo project down the road.
The L83 heads are off the LT 5.3 with 1.930/1.556 valves, so clearing the bore shouldn't be a problem since the LS and LT 5.3s have the same 3.780 bore size. The heads do have large 248cc intake and 102cc exhaust ports, though. The combustion chambers are 58cc, so as long as the 5.3 has flattop pistons, compression should be a tick over 10.5:1. I'd probably look at milling the heads to get to 11-11.5:1.
I'd like to see a comparison between these L83s and ported 862s.
The core ate a valve seat and needs bored. No reason not to punch it out, so 3.907" pistons. Combined with the required valve reliefs I get 11.1:1 +/- about the same as the L83, but with 347ci.
Keep in mind I'm not trying to sell you anything....just offering some helpful advice
-Tony
I don't disagree, and I absolutely appreciate you taking the time to lend your expertise.
As already mentioned the L83 are the smaller LT head and are slightly more efficient although they share many of the design features that make the L86/LT1/LT2 frustrating crap when it could be great.
I'd do exactly as you say if I could, but I can't go out and buy a pair of 243 heads and even if I could, you wouldn't want any that I had worked on. I won't bother my local guy either (even though he'd probably do it).
He's already helped us too much.
I wouldn't even have the L83 heads if they hadn't been thrown in with the short block core that I bought for $100 to turn into a teaching tool. I didn't really have money for that either, but I ate ramen for lunch at work for a month.
I 'd be interested in improving the flow of the heads, even if it isn't elegant. We have access to 3d scanner and printers and a getting a 4 axis CNC mill this summer. I keep thinking there should be a way to "shrink" the ports while maintaining/improving flow
by manipulating the boundary layer, but it really isn't my area.
If nothing else, I'll get good data to show exactly what the combination does. It's looking like a repeat of the 4v 351 Cleveland, like the intervening 60 years of engine development never happened.
02-04-2023, 11:04 AM
