LSXpensive!

I have an LS1, 220r cam (.600 lift)A4, Yank ss3200 stall, 3.42 rears, 1 3/4" ARH LTs, no cats, X pipe, LS6 manifold, CAI.
I know I don't want a big cam and it's personality traits.
I love the low end torque the 220r cam brings. If I put LS6 243's with PRC 1.0 heads, will I gain lots more low end torque?(shaving heads to 59cc chambers) I'm not going 1/4 mi racing, rarely see 100 mph, just want more low end on demand power without going high rpms to find it. Dyno number aren't ultimately important to me(but they tell a tale) I dynoed 369/364 before the rear end/stall. I'm guessing I'll pick up 30-40hp with ported 243's, give a little back with the stall.....but will the heads really pull hard with that 220r cam?
I'm doing the work myself. Hopefully with help. My dad says if you can read you can do anything. I guess I'll find out!)
I bet this combo has been done lots of times on a 5.3 truck that weighs 1500lbs more. Must be fun in a vette!
Massachusetts isn't the ideal place to run around at 100 mph+ or the conversation might be different. These places just don't exist here without exposing others to risk. Racetracks are few and far between here as well. I just try to go fast slowly

Markolc1981

Ported heads should increase your power at upper RPMs the most, but the extra power will be felt at all RPM. If you already have the heads, throw them on, leave the cam you have in there and feel it out. As you increase cam duration from what you have, you will continually shift the powerband into the higher RPM range.

LSXpensive!

Hi Mark,
Good advice. I do not have 243s yet but I will start shopping. Ultimately if I dislike the h/c combo I can always get a different cam next winter, but I suspect I'll be just fine. I doubt the heads will send me in the wrong direction. More power at the expense of a little more rpms will work. I was hoping to hear from someone who had the same h/c combo with similar mods. Seems they are trucks. I am new to Ls engines. The last time I put heads on they were single hump in 1984.

LSXpensive!

Why mess with it? To improve upon it, of course. Isn't that what we are here for?

vette4fl

I have a 218/226 587/587 114+3 Cam Motion cam, so the same ballpark as yours. I have stock 243 heads, stock exhaust manifolds, 4.10 gears (6 speed). Around town its about as much as I can get away with.

Ported 243’s and a tune will really finish off your combo with more response across the rpm range. Ported heads are a no lose proposition, and you can get some 243 cores for under $400.

More cam, more power, but I’m sure you’re aware of the trade offs. Personally, I like the mid range cam and low gearing. Mad as hell to 5200 rpm, but good manners putting around the neighborhood. Like you, there’s nowhere is my typical driving radius that I’m going 100, or even close.

I would be considering lower rear gears, 3.73 or 3.90 for neck snapping response. Ported heads and/or lower gears would be a big step up without downgrading drivability.

LSXpensive!

Im all over those heads and off to TSP. I have newish 918 springs so those will move over. Trunion time.
Have you put you car on the dyno with that cam?
I just put the 3.42s in. I figured it might rev too much on the highway with a 3.73+. I don't know anyone with a modded vette so I have little to go on. I just joined Baystate Corvette Club so hopefully I get a bit more exposure.
Thx for the help!!

vette4fl

My car dyno’d at 366 hp, 370 tq. That’s about 420 at the crank. With headers/port work could be over 400 at the wheels with this cam, but I do like the quieter drive.

I have a speed calculator, so if you like I could jot down your rpm/speeds with a couple gear options.

Markolc1981

If your plan is to buy 243 cores and send them off to TSP and get them worked, then you'd just be better off purchasing their LS6 Brawler heads. Unless of course you plan to keep your springs, then you could save a few bucks by finding 243s, disassembling them, and shipping them.

LSXpensive!

Good call... TSP is sold out currently, and has been for at least more than a month since ive been looking. . Michigan Motorsports has them advertised, but Certainly requires a call before ordering. I'm planning this for this Nov so I am in no rush. I've only had the stall/3.42s for a few months, I do mods in the winter....I was thinking start looking for the cores now and ship them in October for the machine work if I go that direction. I do think it makes sense to get all new heads and parts for the money.

Beast

3.73s may be a little much for you, I like it though, I’m also running a slightly smaller diameter rear tire then stock, 305 30 19, 26.1 inch tire. I turn roughly 2500 RPM at 76mph. I do have drag radials in my garage that I can play around with as needed. I too have a 3200 stall. With all these mods you want, and possibly a fast intake, you already have gear and converter, you might benefit more with a 224/228 cam 224/230 or 228/232, keep it under a .600 lift for valve train longevity. I’m still running stock internals, so maybe more experts can chime in. Sounds like you have a good build going, and almost a top end full rebuild soon.

Also, I just put 3rd gear to the max last weekend at road America. 3rd gear goes up to 125-126 mph at 6,000 RPM, with a cam, 3.73 gear, and 6500 RPM redline, your 60-130mph would never shift into overdrive, or would be right there at about 130. I hit 137 mph on road America straight.

Navy Blue 210

Agree with Beast.
With 3200 stall converter and 3200 lbs
Cam Motion Titan 3 224*/228* should be minimum, imo on a 114*+2* would drive pretty close to stock,
I would even consider the Titan 4 227*/232* . either of those with 243/ported or aftermarket heads will run
great at 11.0 -11.5:1 comp depending on fuel 91-93.
3.42s are perfect also>
My .02

LSXpensive!

According to an email from TSP today it will be another 3-4 months until Brawlers are available. If that's the case I'll probably buy used 243s and get the PRC 1.0 work done, in Nov.
I appreciate the input on cam info. I like all that I hear.
However, I think ill go with the 220 cam and 243 1.0. Probably get a fast 92/fast 92 TB. I have an LS6 manifold now. If I go this route and hate it I can throw another cam in
Is there any reason the fast 92 would not work with a small cam?
I read in a post that a small cam may not work well with a FAST manifold. Is there any truth to that?

Remember, not going to 1/4 mi track, prefer low- mid range torque over top end build. Thx!

Markolc1981

I wouldn't bother with a FAST 92 if you already have an LS6 intake and keeping a streetable cam, at least not right away. Fast intakes tend to really shine in the upper RPM ranges so I'm not sure it will be worth the money, and also you can keep that mod in your back pocket once you get bored of the new power and want a little extra in the future.

vette4fl

This info may be of some interest. I installed the BTR V2 trunnions. There is a link below for the trunnion tool. Same design as the Comp Cams model, but a lot less expensive and it worked fine. I did the swap in my bench vise. Easy. Make sure the trunnion bearings are pushed all the way in, so they are flush with the outside edge of the rocker, and make sure they all rotate easily. Prior to installation I dunked them in a pan of oil and rotated them back and forth until the oil displaced the dry shipping protectant, and they rotated effortlessly.

I had a couple washers that did not want to rotate smoothly, but BTR advised that didn’t matter so long as the rocker rotated freely. Took a few calls to set my mind at ease, but finally got in touch someone who understood what I was talking about. The kit ncludes an extra bearing and washers, so if you mangle one you get a free re-do.

A very well engineered system and I’m happy with them. They are the only ball bearing trunnions with internal oiling holes.

https://www.corvetteforum.com/forums...post1607377907

https://www.corvetteforum.com/forums...today-789.html

Trunnion Tool
https://www.summitracing.com/parts/PQX-1213469

BTR Trunnion Kit
https://briantooleyracing.com/btr-pr...kit-tk002.html

LSXpensive!

Thanks Mark. Saved me $1600. Free seats!
Vette4fl...thx! Ive been mulling the different trunion kits for a while now. It looks like the tool makes sense.
I had 1219 springs put in with the cam (220r /.600 lift) 2 years ago. Roughly 6-7k ago. How often do I need to change the springs? I was planning to send them to TSP with a set of cores.

vette4fl

I don’t know how long the springs last and would ONLY contact the manufacturer for their recommendation. .

Absolutely send your springs to TSP and include the installed height and seat pressure specs from the manufacturer so they can be set up properly. As long as the valves that come with the heads are within spec, they’ll machine and assemble them, or you can opt for new valves. Once you get them back do a cursory inspection, clean with alcohol, and they’ll be ready to install.

Just make sure to measure the zero lash to verify the the pushrod length you’ll need. Anytime you change cam, lifters, or heads this needs to be checked. Comp Cams makes a tool for measuring. Pushrods should be .080” wall chromoly, in either 5/8” or 11/32” diameter. BTR has both available. IMO, you can’t go wrong buying from Summit in general, and BTR for their brand products.

LSXpensive!

If I buy used 243s and they come with rocker studs, do I re use them? I see ARP rocker stud bolts everywhere so I'm guessing no...?
Thanks all for the cam/tech advice! At some point I may do the cam but first I think I'm going to run the prc 1.0 heads with the current .600 lift 220 cam with the ls6 manifold, with all the same bolt ons, and compare.
I ordered a Dragy. I'm going to find a stretch of road that will serve as a track and begin to gather data pre head swap. I'll do the heads over the winter, back to the "track" and compare new times.
I gotta know!!!
The track would be better, but currently no rollbar in the convertible.

Beast

Be careful on the street my friend, you can get thrown in jail if caught. Make sure there is nobody around or coming from the opposite direction. Be safe, don’t hurt anyone. Tracks are better, safer, prepped, and legal. I got my need for speed out at Road America. I’m good for a few more months.

LSXpensive!

That is the issue. I agree. I'm thinking 60' and 0-60, not more.i have a private road in mind.

vette4fl

Studs are $400-ish, so you may be overpaying for heads equipped with them. As with any ARP fasteners for LS, make sure to follow their instructions for assembly/torquing.