Sloppy stage 1 or 2 work great in 5.3s

 

The Brian Tooley is using a little less intake duration though the exhaust at 23X degrees needs some definition?

Basically without timing cards to see exactly where the events are occurring my off the cuff reaction is this is two different routes to the same place. Just trading durations and lifts around. The timing card would tell a lot about the overlap that would tell you useful information that the LSA can only allude to.

Bogie

 

I'm not too keen on 230somthing either.

 

Requested cam card from BTR...... doubt it will materialize.

 

Send a RFQ to Jones and Bullet, just for a sanity check?

How much rear axle gear and how tall of a rear tire are we looking at here? While that doesn't specifically effect the cam, it DOES effect how the vehicle will behave in traffic. For myself? Id want to keep the dur down in the low 220s, but Im pretty conservative when it comes to "street car". With a stick and that deep 1st gear, it'll be very fun regardless, but the milder manners will tolerate the overdrive a bit better I bet.

 

vacillating on the current 3.07 or 3.54 for the rear 26.85" diameter rear tires. first two gears will need to be light on the throttle as there will be wheel spin. I dont generally lug a motor, keeping the rev's above 1500-2000

 

BTR got back with 217/241 .619/.617 114 +3

not really a cam card and 23X = 241 LMAO

 

You're playing with "the house's money" here. I'd leave the 3.07s and get some saddle time. You may find that this doesn't really require the overdrive as much and it'll mellow out that 1st gear agressiveness a bit. Once I'd have some seat time, then I could decide if I wanted more gear out back or not.
My employer has sold over 1000 2.98 1st gear 4-speed gearsets (some as complete units, some as kits, some as just gearsets) in the 14yrs I've been here, and theres piles of 2.88 1st gear T10s in the world.
Generally for a street guy with a short tire, we market that to folks with 3.08s/3.23s and 3.31s or so. 60-65 is about 2200rpms in 4th gear. So for you, you would have the ability to crank it up and drop it in OD for extended 4-lane trips (72-75+) and still keep your engine off the idle circuit and running efficient as you mentioned above.

Our own esteemed Bogie has a 3.07 rear in his S10 with a 700r4 and he's in the PNW, so lots of weather changes and elevation. Heck I think most Vipers were a 3.0x rear and the 2.97 1st, standard fare Camaro/Fbird synchros T56.

Now, if you go rowdy on the cam, with a singleplane and carb, the 3.54 will help you mitigate some of the soft bottom end and keep the RPMs a little higher (with less throttle input) where she runs clean and tight. At the expense of 1st and 2nd gear being essentially " ".
If you plan to let other people drive it; there might be a passing thought or 2 to making it a little less feisty in 1st/2nd?

You'll be fine either way, just some things to think about.

 

my college ride was a 330hp Buick V6 (8000 RPM )in front of a T-50 trans and a 2.73:1 Chevy Monza limited slip in my 2100# Opel GT. I would get 32mpg on the highway at 70mph all day long. first gear would pull all the way to 70mph if I wanted to bang the rev limiter, 2nd gear was 95mph, initial stomp on the throttle just initiated tire smoke once I got the carb dialed in (long story on the holly 650dp). it was useless on rainy days, much less the one time I took it out when it was snowing.

1st gear was 3.10
2nd gear was 1.89

any of my gear-head friends loved driving it. My father took it to work a few times and scared the crap out of his co-workers.

the Fiat should be a lot quicker with a whole lot more torque in the LS. doubt I would let anyone else drive it without a throttle stop or a low rev limiter

Im leaning toward keeping the 3.07:1 D36 in the C4 rear as its there. however knowing a gear set is under $400 if needed. currently when calculating acceleration, everything says wheel spin with the 3.07 rear diff in the first 3 gears



This is what I put together for the car with a moderate 6500 RPM about 3-4 months back. most of the cam changes I am looking at will pull to 7k without a problem

Rear tires are 285/35/19's

Trans. Gears for MW5 Aisin 5-Speed Manual (Solstice)
RPM limit=	7000​
Gear	RPM	Transmission	ratio change	Axle	Final Drive	Tire dia	MPH
1	6500​	3.75​	0.397333​	3.07​	11.5125​	26.85433​	45.1​
2	6500​	2.26​	0.393805​	3.07​	6.9382​	26.85433​	74.9​
3	6500​	1.37​	0.270073​	3.07​	4.2059​	26.85433​	123.5​
4	6045​	1​	0.27​	3.07​	3.07​	26.85433​	157.4​
5	5200​	0.73​	0​	3.07​	2.2411​	26.85433​	185.4​
REV	6500​	3.28​		3.07​	10.0696​	26.85433​	51.6​

 

digging around over lunch, came across this. https://www.motortrend.com/how-to/sucp-1112-5-3l-ls-small-block-build-part2/

its a comp cams XR281RH XFI RPM HI-LIFT 228/230 Hydraulic Roller Cam for GM LS GEN III/IV

if you believe the trade mag.... 480hp, 435 lb-ft.

 

Of course these pop press engines are built by professionals with complete shops and test labs at their disposal which the average guy in his carport doesn’t posses nor is likely to even afford to have a shop like that do the build. So to a certain extent to join in with Johnsongrass1 on this is to say that these engines are ringers. Not that they are impossible but one needs to compare how and where they are built to what’s in your backyard.

As far as believability a very well built Gen I, 305 can easily pull 370 hp on a carburetor with big valve heads and high compression pistons and it isn’t a very efficient engine like the Gen III and up engines. No mater what you do with a Gen I or II it’s still a doctored up mid 20h Century technology where with the Gen III and beyond your starting with 50 years more technology in materials, processes and capabilities. Consider the technical leap between the 1955 SBC and the technology of anybody’s 1905 engine. You can get a glimpse of the engineering struggles and how fast things were changing from the late 1940’s into the late 1950’s By just comparing engines of different makers and how fast designs were obsoleted between the beginning of that period to the end. When looking at introduction model years compare the Ford Y block of 1954 to the Chevy SBC of 1955. The Ford looks like it was designed by Fred Flintstone in comparison. So things were changing fast back then and we saw this again an the 20th century was closing out and the 21st starting.

Similar things were going on with automatic transmissions in this time period as well, the manufactures were sinking huge amounts of monies into designs and facilities to make those designs and some of this stuff of engines and transmissions had some pretty short life spans while some stood the test of time.

Bogie

 

But we are specifically talking Gen III LS 5.3 here. Not the gen 1 / 2 SBC which did start out life as a bent stovebolt variant or the Y-block which came after the flathead

I agree that most trade rag builds are not simply pull a motor from a salvage yard and swap in parts builds that most of us do, even if they claim to.

I take most of these "dyno shootouts" with a grain of salt that I add to the rim of my margarita glass. however I have helped build some fast LS motors with junkyard long-blocks and a cam kit

Just simply looking for real world experience. Plenty with the 5.3 and XR275HR as that cam has been around going on 20 years. LS1tech and other forums have plenty on it with time slips and dyno graphs. only the one youtube comparison on the BTR "Hotrod" cam. some builds I found on the XR281HR were in holdens (AKA Pontiac GTO's) however those were much heavier cars with slushomatics

You mention automatic transmissions....... I am now in the hate them more than lima beans and humus category....... Both ford and gm have soured me on their POS automatic transmissions to the point when it comes to an upgrade to truck, I will be building the next one from the ground up with a Cummins 6.7 and a 6-speed in something pre 1973 unless I get my hands on an 8.3/allison combo. Automatics have gone backwards in reliability over the past 15 years.

 

someone recommended a Crane cam (.590, 224/232, 114 lsa)

 

Summit is recommending the Pro LS 8704 https://www.summitracing.com/parts/sum-8704

 

after hearing what some guys are running for cams in oval racing LS3, i would find a custom cam grinder that understands how the heads on these engines impact cam specs.

 

Won’t be a night/day diff between the two if I’m honest. But IMO I’d favor the tighter LSA MS3. It will be “snappier” and have a little more up top. That summit cam is as I mentioned is “for the masses”. They even mention “the biggest cam for a daily driver” which in my mind means tame! Lol

That’s not for us guys with 2200lb cars. We can get away with a lot more cam. You could likely go more radical than the MS3… the MS4 comes to mind with a 239/242 .649"/.600" 111.5 LSA. Though I’m not a TSP fan boy. Lots of places to get a similar grind. The COMP CAMS 54-469-11 is another that has made over 470 on an SBE 5.3. Its a 231/247 .0.617/0.624 LSA:113

It's all a trade off. Going from say the MS3 to the MS4 you will be giving up a little more power below 5k and gaining more from the 6000 and up range where you want it. Also a tighter LSA which in my experience has always made for a more crisp and responsive cam. More aggressive idle lope as well if that's appealing to you.


Def not something id suggest to the masses with a 5.3 (like the Summit cam) But you aren’t a 3500lb typical car either. You’d also want a decent shortish runner intake to go with it.

Fun project you have going there! Best of luck with it. Not gonna break the bank either way. Any of those cams will scoot in that chassis! More radical ones will just have a bit more umpth up top is all.

Here's my little budget NA rx7 I've been working on. junk yard 5.3. 13.25:1 milled .100 off the heads, otherwise untouched. Fly cut the pistons myself. CD009 trans and a pretty mild 228/232 .550"/.550" 110+5 cam. (i was worried about PTV clearance) Turns out I had a ton and could have cut the pistons alot further. Wish I had went bigger cam wise.

 

You’d also want a decent shortish runner intake to go with it.



Here's my little budget NA rx7 I've been working on. junk yard 5.3.

I will most likely be running one of the Amazon chinesium Holley 300-132 medium rise clones as I dont have much room under the hood.

I like the ITB's. Is that the SCE setup? Borla (old TWM)? , or did you make that from the chrysler LHS V6 TB's like this thread. LocostUSA.com • View topic - Homemade ITB set-up for LS motor

 

Its the Speedmaster kit. Horrible company to work with. Can't stress that enough! But the kit thats normally $2500 was on sale for 40% off this past black Friday. So I bought it knowing it would test my patience and be a total PITA. It has done that and more! But I think I'm close.

Chevy GM LS3 Downdraft EFI Stack Intake Manifold System Complete Polished

SpecsBrand:SpeedmasterPart Number:1-148-002Part Type:Intake Manifold, Fuel InjectedProduct Line:Individual Throttle Body / 8-StackEngine Block Style:LS3Injection Style:8 Throttle bodyBasic Operating RPM Range:Idle-7,000Intake Trumpets:Intake Trumpets IncludedEGR:NoInjectors Included:NoFuel Rails...

www.speedmaster79.com

 

The SCE (speedmaster) was my first guess. If you got it cheap enough, it should be worth it. I have SCE metering blocks on my HP950. I did have to change all the bleeds and set it up properly. They are masters at copying stuff, but don't know what they copied. Almost ran their heads on my BBC in the boat, however was warned the valve seats may come loose at extended WOT runs

The comp 281LRR HR-13 (54-469-11) is listed as a rectangle port cam. However should work with cathedral ports. Still awaiting comp to return correspondence.

 

Yes, def a rec port ls3 cam. But it worked well on the more radical cath port small bore stuff as well.

 

so being the geek I am. I dumped all the cam data into Dyno 2000 to generate simulation numbers. Note, much of the simulation does correlate to the Richard Holdener videos. While it may not be accurate, there is a correlation.

I will have to dump a few more cam cards in there, but based on below, it makes sense to stick with either the TSP-MS3 or the XR281HR.

 

added the Summit 8709 cam as there is a richard holdener vid with the cam and it made great power on the junkyard 5.3. they all have similar trend lines, however the magic stick 3 is still looking to be better from 5500-7500. I think at this point I am suffering from analysis paralysis.

 

Cam Motion finally came back with their Titan 3. However, it's only a 224/228 can. So I asked about the Titan 4....... Crickets so far

 

Have you thought to ask Jones Cams and Bullet?

 

No. Didnt even know they existed. Just looked at them, not much information on their sites, and Bullet cams website is busted if you try to look at their catalog, or something is being blocked while looking from work over break

 

Jones Cam Designs (Mike Jones) goes by "CamKing" on various web forums. While there are many really good designers, he is widely respected and considered the cream of the crop here in the US. He even does (or has done) some work with OEMs.

Bullet is a very good company, they bought a lot of Harold Brookshire's cam designs (Ultradyne, General Kinetics, and the guy who designed some of Comp and Lunati's most famous grinds).

Last 2 engines I was involved with (Non LS) had both these guys quote them. Good pricing, knowledgeable and reasonable turn around (one was jammed up during the Covid era and there were no cam cores available; not the grinders fault.

 

Jones Cam Designs (Mike Jones) goes by "CamKing" on various web forums. While there are many really good designers, he is widely respected and considered the cream of the crop here in the US. He even does (or has done) some work with OEMs.

I bought a cam from Mike Jones several years ago for a 327 Chevy. It was the only cam I ever measured with lift and events that were right on the money. Try doing that with some of the mass market cams which can be +/- a few thousandths and a few degrees. And I may be generous by not saying "several" instead of "a few".

 

went down various richard holdener video rabbit holes. basically any of the 230-234 cams will be more than enough for a small light car.

 

So bored and fueled by whiskey the other day........ started reading about the stock plastic lifter trays on the LS and how some sustained upper-RPM and higher spring rates had the plastic trays deforming or cracking causing the lifters to rotate...... which eats the cam and the glitter fairy spreads its magic dust....

Not sure on the number of occurrences, however it appears if you stay below 6500 RPM your fine with stock GM plastic trays..... its that 6500-7500 RPM range that things happen.

went down a Morel or Johnson link-bar lifter rabbit hole.

Trying to keep this side of a solid cam and stay in the hydraulic lifter range...

looking at some of the "drift" cams which push the power up the RPM range a bit which means power up over 7500 RPM which will keep the car interesting....

I need to stop drinking.

 

Still going down rabbit holes.

Next one is rockers

Stock rockers with lash caps

Or

TSP roller rockers?

Texas Speed & Performance 1.72:1 Ratio LS3 Steel Roller Rocker Arm Set w/ Roller Tip

The benefits of stock rockers.... They are cheap..... They are fairly light on the nose

Roller rockers do free up power that would normally become heat

Then there are all the trunion upgrades....shaft rockers, etc that are rabbit hole adjacent

 

Local seller has new in box Summit 8712. Not ideal, but $50

Another local seller has 1.8 rockers for $100

Toying with this path for the Luddite build to get it running.

Working on a second set of 243 heads for $200