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So I’m putting together a spare motor I have for a 78 Vette that my father handed down from him passing recently. I wanted to pull this 383 and swap in a 5.3. I wanted to use parts that I already have. The motor already has fbody oil pan and a stock 5.3 cam. I had the heads off and did pac1218s and I got a dorman LS6 intake coming tmrw. I have a new LS9 cam sitting on the shelf as well as a 2 piece timing cover with a sensor installed. All I would need is the 1x timing gear and I have a summit cam retaining plate. I also have a used torqstorm centri supercharger that I can on my firebird with a 5.3. In stock form it made 12psi and 10psi with a 218/228 custom blower cam. I have 2 options I can leave the engine alone and bolt the supercharger on it and make 12psi it about 550-600hp or swap in the LS9 cam and pick up the gear and let it eat. I know the LS9 losses a bit down low compared to stock but since this is boosted I would be in boost by 3k so I would think it would make stock like power and then take off above 3k right? I want great drive ability which both cams will give me and losing alittle low end doesn’t hurt the weak corvette rear end. Figure its also light enough to not need the low end as much.
So since I have the cam and cover/sensor would you spend $50 on a cam gear to swap the LS9 or just leave the stock cam? I would rather save the money to put towards a Holley terminator EFI to run the combo than spend $400 on a cam which is almost 1/2 the price of the EFi. The motor already had 70lb injectors and will be good to go.
RH has covered tests with various cams including the LS9.
Really...even a mild aftermarket cam shows considerable gains everywhere. But yes the LS9 would be better than.....who knows exactly what cam you have.
What Richard fails to show ever is real world testing at a track or on the street at big boy boost. What the LS9 does a great job of is limiting power around PK TQ rpm area, and making large strides over stock in the upper RPM. It's a great CAM for the $ imo, just needs real boost and some RPM. Which is also the case with a centri blower. Gear it super short and make use of the RPM, and it'll work OK IMO. Better than the factory 5.3 cam anyway! Honestly 10-12lbs peak will make diddly for boost down low near PK TQ where you'd have to worry about bending rods and things anyway. So obviously an aftermarket cam would shine a bit more for a low boost build.
Yea, I’ve read the articles on the LS9 and factory cam tests as well as the aftermarkets. The low end loss sucks and I don’t like spinning my gen 3 factory rods and bolts much higher than 6500 currently and I don’t see myself spending a lot of time up there where the LS9 shines. I figured given that it’s a
supercharger cam and I have a supercharger it would make more sense to use over the factory 5.3 cam. Even if I only see the gains 4k plus I’m fine with reducing power down low to help prevent bending rods like you said.
So I pulled the balanced and cover last night, looks all original and the chain has some slack in it. Ordered a eBay LS2 timing kit with gaskets for $50 and will throw that in. Cam and cam plate will go in soon. I lined up dot to dot and have the cam pin at 3oclock and crank key at 1:30 so it’s at #6 TDC I hope for the cam swap.
last time I had the heads off I did the fbody oil pan which I put a cheap oil pickup Tube support bracket on so it looks like I can’t pull the pickup to remove the oil pump without dropping the pan... damn it. You guys doing the East oil pump alignment trick...leave the oil pump bolts loose and spin the motor 3x to center it and just bolt it down?
Def. better than the lm7 cam. RPM isn't what kills these motors, and the factory bolts ar ejust fine. Too much cyl pressure too early in the revs kills them quick. It'll spin 7k all day, gen3 or no. But hey to each his own!
Not to mention he never pushes the things where everyone want to see them pushed especially whey you have the opportunity too. Some people want to see say the s475 vs. VSgen2 billet 7875 to its max not interchanging parts between sessions etc. I would want a one for one, like the cam test for example just keep swapping cams so just keep swapping turbos...
Not to mention he never pushes the things where everyone want to see them pushed especially whey you have the opportunity to. Some people want to see say the s475 vs. VSgen2 billet 7875 to its max not interchanging parts between sessions etc. I would want a one for one, like the cam test for example just keep swapping cams so just keep swapping turbos...
How many tests have you to offer ?
And what is the point in pushing something to destruction, when any trends have already been proven ? That makes zero sense when whatever needs to be proven, has already been proven.
So many really seem to miss the point of his tests ? Of course there will always be a million "what if's"....but it would be impossible to test every single thing, they way ever single person wanted it tested. And in many respects it would be largely pointless too.
And what is the point in pushing something to destruction, when any trends have already been proven ? That makes zero sense when whatever needs to be proven, has already been proven.
So many really seem to miss the point of his tests ? Of course there will always be a million "what if's"....but it would be impossible to test every single thing, they way ever single person wanted it tested. And in many respects it would be largely pointless too.
Im not knocking the guy so your missing the point and I'm not missing the point of his test either in fact I'm quite appreciative of them. I'm also not saying push to destruction either that would be pointless and a waste of money and parts that someone else could have eventually used.
My point was you have an opportunity to quantify a test that someone would have loved to see.
I know for a fact there are a ton of people who would have loved to see his s475 vs the VS as I used for an example. Why use a small back side on the VS when the people who are contemplating purchasing either or will not do a T6 1.32 vs a T4 96 but a T4 1.25. That is my point.
Next time Ill just keep my comments to myself and If I have anything to offer too which I actually do Ill just keep that to myself too. Maybe I need a YouTube channel or a shop with a sign to look professional. Maybe Ill do that so I can get some street credit. Everyone knows you have to be a celeb of sorts to know what your talking about these days.
Sorry for the hijack and rant, still would like to know why not keep the 383 though.
Presumably he's just using the parts he has been sent and has lying about.
If people send him parts I'm sure he'll test them.
But most of the tests, the genuine BW units etc do seem to outperform the Chinese stuff. Although ultimately they all make power easily....which kinda makes the tests not that big of a deal. They all work.
I would need all new brackets and crank hub basically I would only be able to use the head unit. Brackets would prob run me 1k easily. Factor in that the 383 has Iron SR torquer heads (Basically cheap iron replacements that don’t flow worth a damn) and then the motor is carbed so that would have to be converted to blow through, carb hat and stuff. I wouldn’t dare boost the 383 with iron heads so I would swap to aluminum heads and drop compression a bit (dunno what the compression is). But if I had to guess no lower than 9.5:1. All I know is he put those iron heads and a small
comp cam inside it.
Swapping to LS I get aluminum heads, EFI and supercharger is a bolt on deal. Besides the $370 Intake and $50 cam gear I have everything to swap it in. I also have a 2 bar stock OS stand-alone. But i would prob still run a self tuning system bc it’s so much easier lol.
Last edited by customblackbird; 08-18-2020 at 05:57 PM.
I was under the assumption it was a well built unit. In that case yeah I would too, by the time you sink more money into it you'll be further ahead and yes way easier.
I was under the assumption it was a well built unit. In that case yeah I would too, by the time you sink more money into it you'll be further ahead and yes way easier.
I’m sure it was a budget build prob a cast crank and hyper pistons. My dad wasn’t going for all out power honestly. I could swap aluminum heads on it and a bigger cam but would prob still have to do a carb upgrade at minimum. The 383 isn’t setup for boost figured the LS would be easier with the drive ability of EFI.
Masked off and painted the motor tonight. Also got my Dorman LS6 intake from summit but dorman didn’t include any bolts with the intake. 40 min on hold with summit they have no more in stock and will have to reach out to dorman tmrw. Dorman LS6 intake should include button head valley bolts, throttle bracket, fuel rails, Map sensor etc. even with the rear coolant block off plates and the front crossover it still hit the front crossover. I had to bend the crossover down a bit and then turn and bend the outlet on the driver side.
overall the dorman intake looks fine, alittle cleaning up/porting will be done in the runners at the head And a little behind the TB opening. Won’t take more than 15 min with a electric grinder and an aluminum carbide bit (did my dorman truck intake before and it was a breeze). Had some old eBay billet fuel rails and tapped the plastic fuel rail mounts in the intake for M6 bolts, 70lb Dekas bolted right on. Weird thing with the intake is that the lower half of the intake has molded in bosses for a nut or bolt head but the upper half doesn’t and it doesn’t extend enough to utilize the holes. Almost like the lower half is generic for multiple platforms and they just change the upper.
I did not swap the cam yet, waiting on the timing chain and gaskets but just mocked up the 2 piece cover with sensor.
what do you guys think this 5.3 could make with the LS9 cam, stock heads, pac 1218s and the dorman LS6 intake NA and then with 10ish psi boost?
Have a 5.3 LC9 with a LS9 cam and T4 S475 turbo . I love the cam with forced induction I barely ever miss the low end torque even though it's a heavy vehicle @ 3900lbs or so. It'll go up steep grades in OD just fine . I love how smooth it idles at 600 rpm and the exhaust doesn't smell horrible and it pulls clean to 7000rpm .
R u running the bbc electric water pump with the ict billet adapter plates?
negative, those are 3/4” spacers so I can use the Fbody waterpump on the truck crank/accessory spacing. Need it for the supercharger and for the car intake. I wouldn’t run electric WP on the street...
08-17-2020, 05:32 PM
LS9 cam for centri 5.3? 
