can confirm, this is a thing. Happened to my best pal and his L76 in his 3rd gen. But it happened after running it then shutting it down. I guess the seat cools faster than the head on a cylinder with an open valve and the seat just drops out.

 

435hp cam only LS1 that ran 10.98 @ 125 right here



modest goal would be 450whp HCI LS1. There’s dozens of ways to do it.

 

Don't sell your LS1 and why your at it go ahead and scratch any thoughts of going with an LS3 or LS7...Apparently those LS1's with the cathedral ported heads are some of the most powerful LS motors that GM has ever put together. You don't need a big camshaft or anything like that just a good induction system with a small LLSR with some worked over 243's and good ole 93 octane and you'll be making 427 ci power. BTW my 01 SS is putting down 540+ at the back tires and you know what? Those are legit #'s on 93 octane from PG and his MD. Hell yeah I can make more, an engine is nothing more than an air pump.

 

Sounds like you need some help modding your 427.

there’s 3-4 LS1 on here the have made 520-540hp. Fairly well documented. If you don’t wanna believe Hios dyno that’s fine, but there’s Darthv8er that maid 540 to the wheels with a LS1 and the same cam and intake as Hio. Tony Mamo had a build last year that made 504 off the hop and later made 520 to the wheels with a fairly mild hyd cam. Chris1313 made 520 to the wheels through a stalled auto like 10 years ago. So, sorry you 427 makes as much as max effort LS1 but bear in mind max effort LS7 can make 650-680whp so your leaving a little on the table dude.

 

Yeah, max effort was not my end goal when I built the engine. It was built for NOS and 200 through a plate is very doable. I'm not butt hurt about my 427's power. It makes more than a stock LS7 and it should based on the cam, intake and exhaust it has. I also haven't gutted my car to shed weight in order to get to 3,300 pounds race weight so there's that.

 

It kind of depends on what the engine is being used for. A 346 needs rpm to turn big numbers. That shifts the powerband upward, that's fine for the track. But a BTR stage 4 size cam isn't optimal for a street engine. People generally aren't doing 4000 rpm clutch drops at every red light(anymore).

 

I have seen this on Mopar (Mitsubishi?) 2.2l 4 shots. Sometimes when it would happen a rocker arm would move off a lifter. Keep in mind this was an ohc engine. But, yes, dissimilar metals, and aluminum will expand more than steel/iron. I can see this potentially happening on any aluminum head with steel seats, depending on how it's engineered. Some companies clearly have superior engineering and machining on some select components. It could potentially happen to anyone.

 

ignoring the pissing contest above...

that ls1 can make 450whp through a stick with those heads if theyre 241's, just needs enough cam/compression and intake/1-7/8 longtubes

 

Convert your LS1 into a 383.....put some high flow really efficient aftermarket cathedral heads on there and the right spec custom cam and you will be blown away by the results relative to what the engine is producing now

Your never going to see a big gain here unless you spend some money.....but with the advice I just gave you I know you would be blown away and absolutely thrilled with the results

22 years ago I built a 383 that made 535 at the wheels with parts not nearly as good as the stuff Im selling today

Can you do if for the type of budget you were originally discussing.....clearly not.....but you have to be committed in this hobby if you want to really shine and part of the commitment means spending the money to build things correctly

Or you spend half of what it might cost to do it right and only gain a third of the performance increase Im discussing here.

You have the foundation there to get you where you want to go but you have to be willing to spend the money to get there or start saving so maybe next year you achieve what you want

It's simple really.....but half measures never provide big changes and your left feeling disappointed with the money spent and the final results.....it's cheaper to build it properly the first time in the long run

If you have an interest to learn more call or email me and we go from there

My 383 in my C5 circa a video taken in 2005....and keep in mind the new heads that I offer now blow these older heads away offering even more potential (the old timers on this board have already seen this video Im sure)


Regards,
Tony

 

Tony, I followed your old build well back in the day as mine was just a year or two after 2007ish. I had damaged my c5z ls6 so decided to make it a 383 (for my first ls build), but reuse the CNC 243 heads and it ended up making 482/445 with the ls6 intake and 501/452 with my ported fast 90 and a 238 242 XER hyd roller. You had a lot of posts about trying different cams and how they affected the powerband, etc it was quite interesting back in the day of very little youtube.

Lots of claims and what not in here, I mean if a car/engine is set up for road racing it needs to live a lot longer at high rpm and have a wider powerband than a drag or street car running times in negative DA then claiming SAE power on the dyno, which could be a 40-50 hp difference (uncorrected vs SAE). Most of this path is already proven decades ago and yes the outliers are doing quite well, but it's done in ways that are quite possibly not for the other guy to reproduce in his cars intended usage. Obviously there are some faster combos out there and I don't want to take away from that fact as it takes talent to put it all together.

 

Have that video saved Tony and we watch it from time to time…I don’t see how you got that t56 to shift that quick. Those headers and X sounded way better on yours vs on my Z.

 

If I was in your predicament I would keep what you have for the time being, as the funds permit pickup that L92 and work with that. Keep an eye on the classifieds here for a LS3 intake and Summit when they have their sales and other manufacturers with Black Friday promos for other parts. When someone asks what to get you for your Birthday or Christmas........I tell my wife to get me something I need for my car.
I had a traditional SB then went to an iron 6.0L with LS3 heads and have a blast every time I take out my ride. Mild cam- 478 ft/lb torque @5000, 507 hp @6100 at the crank with more available and plenty of room to grow with.
Cathedrals work slightly better down low but I've got 350 @ 2000rpm, 400 @ 3000 torque etc..+.........match your rear gearing to the trans gearing along with a good tune and you should be good to go.

.

 

Idk why you crying so much if you're so happy.

5.7s are pretty legit.

His 427 definitely needs some help.

I don't think my 5.7 is max effort at all. It’s really pretty basic ****. Just built off of jaiks combo with a lil' more this and that.

2 more points of compression and 20* of cam, light weight rods, knife edge crank would get it close to max effort.

If you gut a fcar and it still weighs 3300lbs.......then you're just ******* stupid at that point.

Bolt on ls7s has made 540whp and nearly 500wtq.

the cam in my 5.7 is nearly the same as the "stage 4" btr. No need for 4 k clutch dumps to leave a stop light. It cruises in 6th gear fine.

With that said I've always been a proponent of good bolt ons. 450whp is oe cam territory. My bolt on ls6 made 451whp 423wtq. Limiter was set at 7200 rpm. I think a good set of ported milled 243s and a ls7 cam could get near 500whp.

 

Wow that's funny because that's basically what I ******* have Hio and making those same kind of numbers..

Nothing more than a stock LS7 with bolt ons...Same compression, same size CNC heads with just a bigger hyd. cam, 102 intake and TB with KOOKS 2" headers and 3" true dual exhaust.

 

You have brodix heads and a cam. Built bottom end to....that's more than a stock ls7.

If you didn't cross your t's and dot your i's on the build that's on you. 600+ whp is pretty easy for a ls7.

Sometimes it isn't about taking big swings at ****. Maybe just a few small changes here and there......that's usually what makes the difference.

I've said it on here before......you can turn a ls into a sbc if you ain't paying attention. Build on what they gave you.

 

whats your beef with SBC???

 

I was very competitive when I was young, especially in motorcycle drag racing. I gave up spending money and chasing big numbers years ago. Why? I learned a valuable lesson at 20 years old. I had no money!!! I had my 4 cylinder Honda running under the national record in D/modified. The national meet I was going to enter at US131 Dragway in Martin, Michigan, got rained out. By the time the next national meet came, it was out of state. Most 20 year olds dont have the $$$$ to run around chasing records. That, and the record had dropped almost a full second. I simply didn't have the resources. So no matter who you are, there's always someone faster/better/more powerful. It's like a Mike Tyson syndrome. You're the baddest man on the planet......Until someone badder comes along and kicks your ***.....

 

not really what this is about to me. It's about sharing info, techniques and parts to further the development to exploit the performance of this platform. Some people just get offended when their **** gets out performed by relatively lesser builds.



nothing.......love them. Would like to revisit a build with one someday and make more asses raw.

I would look to turn a sbc into a ls......while utilizing oe components as much as possible......including heads. A 500whp oe headed sbc is entirely possible.

 

I guess some of this comes down to a person's definition of bolt-ons. For me, bolt-ons exclude porting stock heads, replacing cams, or replacing any internal engine components, except higher ratio rockers, and FI is not allowed. But altering stock cam timing, headers and exhaust mods, external intake mods, MAFs, U/D balancers, tunes, etc., are all fair game. My opinion, sure to be different than others.....

 

That is the definition. There is no person's definition. It goes back to the 80s and those techniques continue to this day......except some go to the extreme by destroying the car. Then there's these fuels that add insane amounts of power. I don't consider those a bolt on ......they're a power adder.