Me and one of my buddies have been working on a project car together recently. Its a b18b block w/ new bearings, seals, rings, and pumps. It has ctr pistons and a gsr head on top. We strapped it on the dyno tonite. Baseline run. Couldnt even peform a drivability tune with out getting a severe pinging. Pulled timing all the way out on the distributor. Still severe pinging before even pressing gas down to wot. Decreased the gap on the plugs and bumped fuel pressure. Hooray!!! We can now tune drivability with the afc. (approx 25% throttle till 4500 rpms. Finally for a baseline run. 40 mph, 4th gear nailed it. Mph didnt increase 3 mph before sever pinging again. Installed 4 step colder plugs gapped to 28, and added a can of octane booster on top of the 93 octane. Try again..... 40 mph 4th gear....nail it....41,42,43,44,45,ping, ping, ping.
Last try. 4 cans of octane booster on top of 93 octane. guess what ping! Just thought I would put some useful information out there that I wish I could have found before buying this block. Now my next step is to go to a thicker headgasket. Wish me luck. Any feedback is welcome.

 

how come my LSVTEC motor dint ping as much, at least not that much.......i was using GSR head ,oem 3 layer head gasket`and i was running on 91 octane and even tuned on 91 octane......183whp 135lbs.tq

 

CHECK YOU INJECTORS

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b20vtech &raquo;</TD></TR><TR><TD CLASS="quote">how come my LSVTEC motor dint ping as much, at least not that much.......i was using GSR head ,oem 3 layer head gasket`and i was running on 91 octane and even tuned on 91 octane......183whp 135lbs.tq </TD></TR></TABLE> Where you running the ctr pistons????? Maybe the block was machined more than I think it was.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 912 &raquo;</TD></TR><TR><TD CLASS="quote">CHECK YOU INJECTORS</TD></TR></TABLE>Really how come???? I was under the impression fuel doesnt have much to do with detonation. Besides the fact it can help cool things down.

 

thats alot of compression for pump gas... at least mid 13's

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JCushing &raquo;</TD></TR><TR><TD CLASS="quote">thats alot of compression for pump gas... at least mid 13's</TD></TR></TABLE>
Word up. Good luck with that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MassScene &raquo;</TD></TR><TR><TD CLASS="quote">Really how come???? I was under the impression fuel doesnt have much to do with detonation. Besides the fact it can help cool things down. </TD></TR></TABLE>

Running lean can cause detonation.
Reason being what you said lean a/f mixture raises combustion temperatures.


Detonation=Pre-ignition

Try running a thicker headgasket like you said.

What kinda fuel setup are you running.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MassScene &raquo;</TD></TR><TR><TD CLASS="quote">Really how come???? I was under the impression fuel doesnt have much to do with detonation. Besides the fact it can help cool things down. </TD></TR></TABLE>
How much fuel it gets has a lot to do with suppressing detonation. Look at what you did it got a lot better when you raised the fp. Excess fuel cools things down from more evaporation and a rich mixture burns cooler. Too much heat is what causes detonation. Keep giving it more fuel until the ping goes away but so will your fuel mileage, one good reason to not use ctr pistons in anything but a b16. Dan

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dan Ruddock &raquo;</TD></TR><TR><TD CLASS="quote">
How much fuel it gets has a lot to do with suppressing detonation. Look at what you did it got a lot better when you raised the fp. Excess fuel cools things down from more evaporation and a rich mixture burns cooler. Too much heat is what causes detonation. Keep giving it more fuel until the ping goes away but so will your fuel mileage, one good reason to not use ctr pistons in anything but a b16. Dan</TD></TR></TABLE>

Agreed

Check the PCT/CTR thread. I believe you can get the set-up to work but you will need some 'high' octane gas &gt; 104.

 

yeah no kidding, id still prefer mid 11's so you can tune a/f ratio and tune timing maps to make power not so the car will limp around without pining. the goal is afterall to make power.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JCushing &raquo;</TD></TR><TR><TD CLASS="quote">yeah no kidding, id still prefer mid 11's so you can tune a/f ratio and tune timing maps to make power not so the car will limp around without pining. the goal is afterall to make power.</TD></TR></TABLE> well the thicker head gasket is now in posession. i am waiting for my cam gears before doing the install. as for the fuel setup, everything is stock except for the afc, fuel pump and fpr. so far the problem hasnt been lack of fuel. I am hoping this set up will get me buy happily till i get cams, injectors, and better management. looking for 180ish whp.

 

What kind of tuning setup do you have? A chipped ECU+ a wideband= incredibly necessary. Just bump up the fuel curve, I doubt your setup will bring the injectors anywhere near 100% cycle.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MassScene &raquo;</TD></TR><TR><TD CLASS="quote"> so far the problem hasnt been lack of fuel. I am hoping this set up will get me buy happily till i get cams, injectors, and better management. looking for 180ish whp.</TD></TR></TABLE>

My question is how much damage was done by running so lean that detonation occurs, not during a single startup but during driving. All that I can see are scored cylinder walls with improperly seated rings.

 

What ECU are you running? I'd say to try some less agressive igniton maps, and more agressive fuel maps?

Also, Bigger cams may just be what you need. A bigger cam will drop the dynamic compression of a motor.

I'm running an LSVTEC with CTRs and a PR3 head, Agressive timing maps, (Timing 16deg BTDC), both cams advanced, (semi-)Tuned with VAFC and mugen chip. Yes, running only 93 octane.

Motor runs great, never any pinging issues, ever... but I'm running fairly large cams.

I don't see why you wouldn't be able to run that motor on 93 with proper cams, and a proper tune.

 

Do you really think that by adding more octane booster that you're increasing the octane of the fuel with each can you add?

 

Really how come???? I was under the impression fuel doesnt have much to do with detonation. Besides the fact it can help cool things down.

only because when i did ls vtec, b18b p30 pistons standard bore, gsr head,pherable.net chipped p06, started it up had pinging sounds it was a fresh rebuild, i was like damm what the f#@k went to work boss said your runnin lean check your fuel system, pulled injectors out to find that the # 3 injector the tip was broken it wasn't spraying right i guess causing it to run lean and ping

 

Look into Toulene as well... If you need to use it.

Octane booster bottles are crap IMO

 

I have been down that route. B18C5 Block/ CTR pistons GSR head OEM head gasket... my gosh that was a whole lot of detonation going on. Especially going up hills. I hated it.

 

Just run a half race fuel half 93 octane mix. That is what I am going to do. Also you might want to find out exactly what your c/r is. I bet your compression is too high. Detonation can have a lot to do with compression.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSVT3K 91 C1V1C &raquo;</TD></TR><TR><TD CLASS="quote">Look into Toulene as well... If you need to use it.

Octane booster bottles are crap IMO</TD></TR></TABLE>

+1

You've got to have at least 13.xx compression. Wow. I'd definately check the compression if I were you.

 

Fuel has a lot to do with detonation! I run 370cc injectors on my allmotor setup.

I'd at least upgrade to 310's and throw the AFC in the garbage. Chip the ecu and start playing with fuel and ignition maps.


Do you know what your total timing was?

 

this is a sign that you need the biggest cam you can fit in there...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pomansouth01 &raquo;</TD></TR><TR><TD CLASS="quote">this is a sign that you need the biggest cam you can fit in there...</TD></TR></TABLE> Your not the only one that is saying this. I am about to spend money on the gasket and still have stock cams and valve train. If this pinging situation can be fixed with bigger cams lol i would definetly rather do that.
the computer we are running is a p30 that was sent out to spoon. just to let everyone know we do not have a fuel supply problem as of now.

 

a cam with LARGE primaries will help blead off some of that part throttle compression. just getting cams with a big vtec lobe wont help you part throttle up a hill at 4k...