I’m wondering, how far have you guys gone on boost with pump 93 only? No meth. No additives. I’m at 18-19psi nominal right now and it’ll peak at 20.2 on the 2-3 shift. I’m running 12.5 degrees timing till about 6000 and tapering up to 13.5 by 7000. 9.4:1 compression 5.3.

just curious. I did have to pull a degree of timing at the 4800-5200 spot on the 2-3 shift. It was pulling one degree after making a couple passes. I will say, it was a huge different going from 15 psi to 18-19. I’m pretty surprised.

 

What do the plugs look like after a 3rd gear pull at 20 psi? That's getting up there. Surprised it's handling that much timing.

 

I have not done a plug chop. Heck, I haven’t even pulled a plug. I’ll go pull one for you. Wreck less I know. However, my car is very quiet and I can hear when it rattles. I am conservative on timing at torque peak. Afr is fat too at 11.2 up to 6000rpm and then it Richens up to 10.8 up higher. Lemme go pull a plug.

 

General rule of thumb is if it's detonating Lou's enough to hear during a pull you may have already done damage. Definitely check those plugs. You really only need to do it once so you can find the hottest cylinder and then just check that one to dial it in. 11.2 isn't rich to me at all for that boost and 93.

 

here’s the notorious cyl 7

 

What type of plugs are those? Pics need some help but the timing mark in pic too looks like it's too much.

 

So I forgot. My wideband reads about .2-.4 leaner than it really is. I totally forgot about that. So really my afr is 10.6 in higher boost and rpm and 11.0 mid rpm and boost. The wideband is far back in the exhaust and I have a slight leak at a joint before the wideband that I just can’t get to seal perfect. It’s a slip joint.

 

Looking a the 3rd plug you've got too much heat in the threads too. I'd go to a colder plug, preferably nonprojected and probably pull a degree or 2 and reassess.

 

tr7ix iridium. So you think I need to take a degree away?

 

The problem is, those plugs aren’t fresh. I’ve had the timing too high in the past. So I’m not sure how accurate that is. I’ll buy a new plug and make a rip and check it.

 

I'm not a huge fan on projected tips on a booster setup, especially one running that much boost on 93 only. If you've change timing then I agree, plugs are a no-go, but you can see you've got too much heat in the threads. If you get a new plug in there and get a good 2-3 pull it'll be easier to confirm what that plug looks like.

 

will do sir. Appreciate the advice.

btw, I’ve not heard any rattle in this motor. If that means anything lol. I’ve only seen it pull timing one time and that was last night on the 2-3 shift. So I pulled some just to be safe.



on a side note. I got tired of getting beat or running side by side with people. Raced 4 new Camaro’s. I wasn’t happy with the outcome. The first two were like 17’s or 18’s. One had a cam. And drag wheels. The other said he only had headers. My ***, I heard him purge nitrous. I was dead even with both of them or beating them. Except if we ran em out far they would start to creep on me. Well one did. I wasn’t happy. Then I raced a 10 speed 2019 up zl1 with mods, mods unknown. This was Friday night after I added another lb or two. He jumped out on me (boost lag) and I stopped him from pulling. I was on his back bumper. Again, not happy. So yesterday I took the wastegate off and added a stiffer spring. That bitch runs now. I wish it would have been like this Friday night. Ida walked him. I’ve been trying to be easy on it and not go up in boost because the driveshaft and axles are stock. So guess I’m gonna see what happens. I had plans on doing my meth this weekend but still waiting on a part. I was redoing my charge pipe near the throttle body. Then I’ll install the meth before the throttle body instead of before the turbo as it is now, I haven’t been using it as it is right now btw.

then next plan is a full 3.5” single exhaust to replace the 3” single I have now.

 

Careful when changing exhaust, you may find more boost lol. Your driveshaft and axles should last if you're not hooking from a dig.

 

yea I’ll probably have to swap springs back. Or, just go with the extra boost. Lol.

 

used to run 20-22 on my pickup (basic 5.3 build) with tr8 plugs.
my evo saw 30-32 on a daily basis when i had the stock 2.0 short block in it.
its been a little while since i was pushing a turbo car hard so the details are a little fuzzy off the top of my head.

 

I have been wondering how far I could push my truck on 93-I am around 8-9 PSI now, when I was playing with the boost reg I had the Holley set to kill ign over 13, I could see it spike to 15 for a second. Guessing due to the weight of the truck, over 4K, I prob cant run as much boost as a lighter car-thinking 12 could be a safe spot. May do a trip to a dyno just to get a baseline.

 

So far I hit 15 in high gear, but I'm also 10.5:1 CR. I'm going to swap in a 9 inch and drop from a 4.10 gear to a 3.50 which should make more boost lol.

 

See what I’ve noticed is with my 5.7 with like 10.5:1 compression, at 11-12 psi I had to have 11 degrees of timing. This 9.4:1 5.3 will take 13 degrees at 18-19psi. At 12 it’s like 19ish. I’ll confirm this evening.

the key to mine is it would clatter on the 2-3 shift so I added in tq management on the shift so it pulls a few degrees on the shift and it goes away. So if anyone picks up knock around 4800-5200-5600 rpms, Try adding some tq management on the shift and see what happens. If it don’t help, just pull a little timing in that area. Kind of a band aide but iirc the factory map has less timing in the 5200 range too.

 

what compression? If it’s in the 9’s you should be able to get 15psi out of it. Just run your afr fatter around 11.0-11.2. At 12psi, I leaned my 5.7 to 11.6-11.8 and it broke a piston. Stock pistons.

 

How much power you guys making at such high psi? My car does 30ish HP per psi with twins. My buddies making 500 at 9psi with a single. Both on stage 2 cams with 5.3. I could t imagine running 16psi on either car on pump gas. Hell my tuner has me running M1 on the 14 I’m in now.