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No worries man, not upset at all. Just don’t want some poor kid to throw 20*+ at his tune without reading plugs and taking “baby steps” as you say. I am talking about E85 as well. I torched my E85 5.3 on 17* timing and 25lbs. (thats intercooled with water/meth inj as well!) Tiny cams that don’t bleed off compression on small bore engines with fast burn head designs don’t need much advance... esp if you are running 10:1 plus compression wise to start with. I’ve seen LS stuff make no noticeable gain MPH wise over 11-12* of timing. Some took 20-25*.
Ethanol burns faster flame front wise than 91 octane. With 2 identical engines MBT timing will be lower on E85 than it will be on a standard premium octane (91/93) tune. This is of course assuming you can reach MBT timing levels without detonation on both engines. If you can’t, guys will crutch the “pump gas” tune with super low advance... that’s a different story as E85 will of course not need that crutch.
I’ve read about some being 4-5* off, but personally never seen any that bad. Believe my first GEN3 5.3 was 3.5* retarded on my AEM EMS. Verified TDC with a piston stop. My gen4 stuff has been within a degree or so on the mS3 setups. I'm sure like everything GM there is some sort of tolerance.
Also now that I think back on it I wonder how the dished piston and piston stop setup worked together. That may have been a mistake on my part.
I’ve read about some being 4-5* off, but personally never seen any that bad. Believe my first GEN3 5.3 was 3.5* retarded on my AEM EMS. Verified TDC with a piston stop. My gen4 stuff has been within a degree or so on the mS3 setups. I'm sure like everything GM there is some sort of tolerance.
Also now that I think back on it I wonder how the dished piston and piston stop setup worked together. That may have been a mistake on my part.
I have done only 3 engines checking timing all Gen 3 and have had them from 6 advanced to 3.5 retarded. Always check as there is no better way to keep your pistons from being ashtrays
Since mine is apart right now, I’ll set up a timing pointer after I degree the cam so I can check this.
I set timing at 16-17 degrees on all the turbo E85 cars I tune. Plugs always show the timing is good.
Hi bit of a newbe but would love your advice Stock ls1 lil jons s2 turbo cam and springs billet 88 BW clone in a boat E70 mix. started at 10 deg and 7.5 afr on the E85 scale 3000 rpm was egt at turbine inlet 1650 ucu took 5 deg out due to knock, timing checked at 0 deg and was correct.changed the sensitivity in the holley software down to 50, ran leaner to 8.5 afr ran to 5000rpm and egt up to 1900F getting worried, upped the timing to 14 ran to 5300 still over 1900F cooked the fibreglass wrap off from between the header collector and turbine.but no knock.still throttle left and plugs still look ok nippon denso 22 heat range. Hoping this weekend to move the egt to no7 header tube 1" out from flange and add another stand alone wide band for lambda aiming for .8 thinking of upping the timing to 16 then 18 to lower the EGT
What are your thoughts?
Hi bit of a newbe but would love your advice Stock ls1 lil jons s2 turbo cam and springs billet 88 BW clone in a boat E70 mix. started at 10 deg and 7.5 afr on the E85 scale 3000 rpm was egt at turbine inlet 1650 ucu took 5 deg out due to knock, timing checked at 0 deg and was correct.changed the sensitivity in the holley software down to 50, ran leaner to 8.5 afr ran to 5000rpm and egt up to 1900F getting worried, upped the timing to 14 ran to 5300 still over 1900F cooked the fibreglass wrap off from between the header collector and turbine.but no knock.still throttle left and plugs still look ok nippon denso 22 heat range. Hoping this weekend to move the egt to no7 header tube 1" out from flange and add another stand alone wide band for lambda aiming for .8 thinking of upping the timing to 16 then 18 to lower the EGT
What are your thoughts?
Is the setup intercooled? Inlet temps? How much boost are you running? Have you checked cranking compression? Sure cam isn’t off a tooth?
I’d verify those EGT temps are accurate. If so, they are extremely hot and you should not operate at those temps. I doubt those temps are very accurate as they would be melting plug straps. And your plug reading would not be “OK”. Do you have a pic of your plug? Do you know how to read them properly? What procedure did you use to read the plug?
Have you checked cranking compression? Sure cam isn’t off a tooth?
Straight from NGK
Whether the spark plugs are fitted in a lawnmower, boat, or a race car, the spark plug tip temperature must remain between 500C-850°C. If the tip temperature is higher than 850°C the spark plug will overheat which may cause the ceramic around the center electrode to blister and the electrodes to melt.
Problem with EGT readings and “group opinions” is they can vary a TON depending on placement and thermocouple used. For example I ran mine around 1500. Around 1700+ it would munch a head gasket every time. Others report no issue above 1700 and some target much less...
What WBO2 are you using that reads E85 AFR? Are you sure the WB02 readings are correct? Can you verify with LAMBDA numbers? Or “gas scale” numbers?
Knock likely was not happening either. You were probably just getting goofy harmonics that the sensor picked up on. Without OEM style soft mounting, knock sensors are basically useless. There is too much noise in general to detect actual knock VS noise in general. I’m not saying they aren’t great tools, just that many times they aren’t useable.
thanks
timing was marked at tdc and is at 0 when programmed to 0
egt sensor was boiled in water and read 100 deg C
Water to air intercooled 5200 at 8 psi MAT 97deg F
Holley NTK sensor thru the holley software
runs to well to have valve timing incorrect
no I haven't checked cranking compression
no I haven't got an accurate plug reading as the boat is single seat enclosed cockpit and gets driven back to the bank but they are not blistered or melted but the heat band is nearly at the base
Last edited by selff123; Aug 23, 2018 at 06:26 PM.
Reason: More information photo
Sure sounds like something is off. 1900* temps would read extremely hot in the plug. That one hasn’t even blistered the cad near as I can tell. Which makes me think it’s likely fine with a false hot EGT reading. You’ll have a clear marking where the cad plating blisters off when it gets close to optimal on the tune. Don’t’ want it getting down past the 2nd thread or to the bend. Pic is about perfect, if slightly aggressive.
Then again I’ve never heard of cooking off heat wrap either. I run 16lbs or so non intercooled on E60 with 19* in my 5.3 and the heat wrap is perfectly fine.
Only time i’ve seen manifolds glowing at moderate loads like you are talking about is when a cam was installed a tooth retarded. Compression check might be a good indicator. The engine was just down on power... it idled and drove fine (aside from glowing manifolds). Might also verify timing as you raise the RPM and ensure it isn’t wandering.
Did you degree the cam when you installed it?
I also had a 5.3 with a crank keyed 8* retarded from the factory. Installed my cam dot to dot with oem timing set. It idled great and ran smooth. Just way down on power. Re-degreed the cam with 8* back in it and picked up 12MPH at the track at the same boost level... (if you aren’t a drag race guy thats a huge power gain) I’m betting EGT was thru the roof on that setup too.
To get a good WOT fuel reading might be impossible, but to get a good heat reading you should be ok. Just toss in a new plug and go WOT. (no anti-seize) Pull plug when you can. Having a bunch of idle/cruise time on it will just foul up the fueling marks, not so much the heat mark on the ground strap.
Best of luck with it... its will need more than a tune adjustment IMO.
Thanks again for your input
Next time in the water we will try a few other variations with the egt probe 1/1/2" out from head header flange
15 deg and super rich with fresh plugs
then 20 and see if the knock sensors or plugs show detonation
And take it to 6000 this time
Yes the cam was dialed in with a new rollmaster chain specs were for 109 centreline and it was 109.5 so I left it alone
I'll get some DEI Titainium wrap as the chinese stuff on it obviously cant cope
just for your interest a clip at 5200rpm
https://www.facebook.com/133853830004136/videos/711088422561733/
Looks like fun! FWIW I use the cheap lava rock china stuff on mine. Secure it super snug with .040 SS wire and hose it down good with BBQ grill paint to help seal it so it wont soak up moisture or oil. Has worked really well for me. Stays on for years.
I’ve been wanting to read my plugs, but I’m not sure how to go about it on the street.cant I just go WOT in 2nd gear, then pull over and pull a plug? Top of 2nd is 80mph. too much traffic around here to do much else.
OK so all went well
egt probe at header flange, afr at 7.5 programmed in the holley software, E85 scale,another wide band standalone in the dump pipe to read lambda scale
6200 rpm 8-9 psi boost 16 deg timing 1530F egt .78 lambda
Where I was going wrong was thinking I had to program in altered AFR ratios for the E70 fuel scaling them between E85 stoich of 9.9 and gas At 14.7
wot 8.5 or 12.5 gas I found a table for percentages of ethanol blends and AFR ratios to suit which I used as a guide BUT I was wrong. the programmed AFR in the Holley must be/ is just a lambda reading and scaled to E85 or gas so the blend doesn't matter the reading will be same but will take more(high ethanol blend) or less fuel in the base table to get it.The Holley data was 7.5AFR and the standalone lambda .78 which is the same (well almost)
next run more timing and fuel
That’s great news... Should really be able to turn that sucker up now! What RPM are you targeting? I know the props load the engine a bit differently, but I’d steer clear of PK TQ timing from 4800-5400ish, then pour it on after. Cylinder pressures/heat can get ridiculous around there, esp. if you load it for long periods in that range.
I was thinking only 6500 and 10-12 psi. I put arp rod bolts in those skinny gen3 cracked cap rods so maybe a bit more later on, the plan was less revs than 500+CI BBC that came out, and use the torque of a turbo LS and bigger gears for the same speed. Best was 144MPH @7200 BBC before and we got 131@6200 with lots to learn and more to go with the LS But it is alloy 5.7 junkyard with a few fresh bits so don't want to break it too early.
this clip is at 5600
https://www.facebook.com/133853830004136/videos/903454796504941/no one filmed the last lap at 6200 just our luck as she was actually flying as a hydro should
whats your thoughts on more power at the 3000 mark? boost is there but big load with our big gears in the corner I was thinking boost control I'm just on spring only now,give it more 3000-4000( if its there, to get) then back it off again for the straight and longativitiy of the engine hydros need less power when they are up out of the water
Last edited by selff123; Aug 28, 2018 at 06:16 AM.
I’m trying to relate drag racing experience to boating... So probably not the best guy to take advise from. I can see a turbo LS boat in my future though, so I’m trying to learn what I can about them.
90% of failures are crushing the ring lands and/or bending rods. I’ve yet to see a turbo LS fail due to rod bolt failure or over revving. Aftermarket rod bolts or not. Latest trend with the record holder SBE guys to it rev them clear past 8k. One of them has the limiter set at 8400 and I’ve heard him hit it on many passes. Last I checked on FB he had almost 90 7 second passes at over 170mph on that engine this year and is still going.
I’d be more worried about the GEN3 rod strength at low RPM than anything. At 10-12lbs I don’t’ think you have much to worry about. I think you’d be fine up 15 easy the way it sits, likely more. I’ve bent a few GEN3 rods around 800ish crank (25lbs on my setup) with a very conservative tune... but I wasn’t geared to rev it over 6500. Think I shot myself in the foot there. I’ve seen others bend the gen3 stuff around 600hp. It’s mostly in the tune and how you load it at PK TQ IMO.
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