Good evening all. New to this whole Corvette thing, but learning very quickly. A 2000 C5 that was built up and modded in 2000 literally fell in my lap. I knew very little about the car when we got it other then it was supposed to be a 383 stroker. The build was done in 2000 with 200 miles on the car. The car now has 19,000 miles. When I got the car, I took it and got it looked over and thought why don't we dyno and tune it and see how it does?? Car made 417 to the wheels and 418 torque. Car at the time had a Callaway Honker Intake, factory stage 2 heads port and valve, cam (not sure, but on the smaller side), 1 5/8" headers, what I believe to be early Corsa exhaust and that's about it. Felt great for a while and I thought, I need some more power!!

I did a bunch of research and found a guy who worked on and tuned LS motors. He thought we could get more by doing a LS2 Throttle body, Fast 92 Intake, 1 7/8" headers and we already needed to do the dampner so why not do a slightly larger cam. I bought a Mamo Ported LS2, Mamo ported Fast 92 intake, 1 7/8" headers and a 236/238 115 cam (per tuners recommendation). Put the car back together and made 477 RWHP and 435 TQ on his dyno. Had some issues with him getting it tuned, it would hang at 1500 and then almost die. Back and forth and I would say we got it 90% there in regards to the tune.

So I took it to the 1st guy that tuned and dyno'd the car, to see if he could get the bugs worked out of the tune. Went back on his dyno today and made 460 rwhp and 407 TQ on a baseline run. He is going to put on the a 85MM MAF I had to get rid of my 75MM MAF to complete the MAF/Throttle/Fast mod to the car. Then he is going to dyno tune it with his tune and the 85MM MAF.

I will say the car feels faster especially above 4000rpms and makes power longer. I would say this cam is a little tougher to drive around town, not bad, but a little tougher. I would say Lower RPM feels the same ish in regards to power, higher RPMS more power? Is the 236/238 115 cam the wrong choice, I wouldn't have thought losing torque would be a good thing? Or is this what you would expect from the parts I added? Where did we go wrong, or is this about right. I spent allot of money for 50hp lol. Thanks

 

This is the 1st tuner baseline car as it sat when I got it with his tune in blue. Baseline today in red after all the work. I will find the dyno from the gentleman that did all the work that shows 477/436. I am so confused, lol.

 

You should have left it as is, then get A and A or ECS supercharger and you would make massive power.

My C5 is still stock and will go with one of those brands centrifugal supercharger, maybe long tube headers, even with stock exhaust manifolds on stock LS1 they make 500 or more rear wheel horsepower.

 

You make good points in favor of going FI. BUT-I'm glad the OP went for a change. Granted, his cam may be a little hairy for everyday/street use, but the build was done in 2000!!! Cams have developed in leaps and bounds since then. Hell, the LS1 design was only in only its 4th year of production in 2000. Much has been learned and developed in the last 22 years.......

 

You've already done the work now, but I agree that you would have gotten a better result from adding a supercharger to the setup you had when you bought the car. I have an A&A kit, and I LOVE it. The car would have been just as easy to drive on the street, but you would have gained another 200+ RWHP. IMHO an aggressive cam build is better suited to track cars.

 

Thanks for the replies thus far. I was all game for ordering a kit, I talked to both A&A and ECS and both are on back order until the end of season. The shop I am working with just got and ECS kit ordered in January. Like I said I called both to order, unfortunately, there is not kits:0( and I didn't feel like waiting. On second thought I should have just been patient and waited, but I didn't. So now, I just have to figure out how to get this set up running right. Thanks again

 

Yeah, parts are hard to come by all around right now. Good luck!

 

I didn't see anything about the fuel system on the car. Is it stock injectors and fuel pump? Might be time to upgrade injectors and fuel pump.

 

Does have "upgraded" fuel pump and we did 42lb injectors with the Fast/LS2/Headers and so on. Hope this helps. Thanks

 

Tuner just got done with the dyno tune... looks pretty good picked up a fair amount of torque! Was wondering where that went. Next he will street tune. Thoughts?

 

I bet it ran just fine before these "improvements"

 

Are you talking about the retune or all the parts we just put on, lol. With all the parts it is definitely faster, was it worth it probably not, lol. You live and learn, if I had it to do over again, I would have done headers. I'm not sure how much the intake and throttle body added? I am guessing I would have got to 435ish with just the headers? That would have been a cost effective mod. The other things were allot of money to spend for 30ish horsepower over what I would have had with headers. I would not have done that cam, the cam I had was just fine. That said 467rwhp at the wheels is a good number. I will see after I pick it up, how it behaving, lol

 

Honestly, I think you're pretty light on power for a 383 stroker with a Fast Intake.

Going from 1 5/8 to 1 7/8 header probably didn't net much of a gain at that HP level.

With all that cam you now need gears. More cam needs more gear. If you are running a 3.42 in it make the leap to 4.10s. You'll absolutely adore driving the car with that power and cam, with a 4.10 gear. It will rip when you get on it and low speed driving & from a stop will improve drastically.

 

How will 410's do on the highway and all around driving? Thanks for the suggestion

 

They are a great gear in a big cam NA setup. I drove 428rwhp/408 TQ with that gear on an LS1 H/C/I for many years. I don't have first-hand experience with 383 stroker build. But many that do run either a 3.90 0r 4.10 gear.

I've had both the 3.90 and 4.10s and 4.10s are outstanding. Cured all that low speed parking lot clutch manipulation instantly. And highway driving is great. 6th becomes a pulling gear and as a lucky byproduct the exhaust drone many have at that 1800 rpm mark in 6th goes away completely because the RPMs at typical 70mph highway cruise is just above 1800.

The 3.90 in the MN6 is almost exactly like for like gearing as a c5 Z06 with 3.42s. The MN6 with a 4.10 is marginally higher in the RPM band in all gears.

 

Go with the 4.10s!

might as well go w a RPM built dif when you do the gears.

 

RPM is the way to go.

https://rpmtransmissions.com/product...differentials/

 

For all those of you who were wondering... please see final Divo dyno tube below... not bad!

 

Nice! You have to love that low end torque from a 383 stroker!

Now that it's dialed in how does it drive? If she's happy now with the tune, driving perfectly at low speed as well as high, and you are happy, you may not want to explore the gears.

Just get out and enjoy that baby!

 

Thanks for the reply.... How does it drive??? That's a good question, lol. I would say it drives great ish. I have had 2 really good tuners work on the tune. For some reason it will randomly hang at anywhere from 1500 to 2000? Picked up from the tuner drove 30 minutes home no issues what so ever. Pull into the drive way and it hangs at 1500 almost like cruise control, all the way up the driveway. Shut the car off, went in for an hour or so and took it back out, hung at about 1800 for 3 or 4 minutes. Then it went away?? I can't find any vacuum leaks, pcv is all there? I am thinking maybe the throttle body, sticking blade or something along those lines?

I am going to switch out the throttle body with either another ported LS2 or my ported LS1 that was on the car. If anyone has any ideas of what to do, please let me know. Thanks