Newly built motor running great at 14* WOT timing?

[DR BOOST]

Need to use different spark plugs. They are supposed to be a taper seat with a .460" reach and 5/8" hex. The Autolite # 23 is an example of the proper spark plug.

With the plugs currently being used the tip will be extended well into the chamber. This causes two issues, the first is that it is the same as advancing the spark timing some. The second and more important issue is that the threads that are protruding into the chamber can glow red.

This will cause pre-ignition. Which may be what happened.

RemoveBeforeFlight

+1

you are using a long thread, gasket seal plug on a head that requires a short thread taper seat.

whats the part number on the plugs you are using now?

 

[TurboDave]

RmvBfrFlght is correct. You have completely the WRONG style/type plugs in there.

Autolite 23's or 24's depending on the heat range you want are best. Probably 23's !!!!!!!!!!

 

[forcefed86]

Not sure why I didnt' get an email notification on this thread...

Well don't I I feel like a goober! Although i'm sure it doesn't have much to do with my timing settings I'll get the correct plugs in there asap. I toatlly spaced out on the plugs. Thankyou for pointing this out!

Anyone know the NGK plug PN off hand for the shorter reach taper plug?

 

[Pronto]

Stock heads. I run NGK UR5s at .030...

 

[forcefed86]

Stock heads. I run NGK UR5s at .030...

Thanks, although accoring to NGK's listing that is a projected plug.

I"m guessing I"d want a.... NGK R5673-9 (3442) (yes I'm looking for a 9-10 heat range thats not a typo)

http://www.ngksparkplugs.com/images/pdfs/product_list.pdf

 

[87buickracer]

motor break down... is in my sig.

Dropped this “fresh” the engine in the car and after a lengthy break in, immediately blew both head gaskets at 18* timing and 15psi. Not sure what happened here. I was running 11.8-12.0 AFR's. No knock, no detonation on plugs. I'm told with alcohol fuel (I run e85) you skip the detonation and go straight to pre-ignition. This may have been the case. I've since replaced the OEM HG's with SS shims and studs.

In a mad dash I made it out to the last few hours of the local test'n'tune this weekend. With a overly conservative tune and surprised myself.

I mixed my own e85 this time around to assure I had a decent blend. Also since the last incident I use a fuel/ethanol percentage tester to verify 85% ethanol mixtures. At 14* WOT timing, 10.0-10.2 AFR's and 19psi I went 10.79 @ 128. That was with a weak foot brake launch of 1.67. Later I played with the t-brake a bit and managed a new personal best 60' of 1.51 on a 9-10 lb brake launch. This was with 19psi in a 9" x 26" slick. Lots more left there. Unfortunately I had issues blowing the charge piping off at anything over 19psi. So I didn't get to turn up the boost.

At this point I'm thinking the timing on the car is off somehow. I do have a MAF translator II installed. Timing settings are straight up. Using turbo tweak chip to control timing only (set at 103). Grounded the aldl pins and I'm seeing 13* or so at the crank. I'm stumped, yet happy.

(Signature doesn't seem to be updateing?)
86 Rx-7 GXL Hybrid 86 Grand National motor. (2820lbs race weight) (9:1) TRW pistons, Webber ported IRONS, Turbo Tweak E85chip,Translator plus,PT68 turbo,CPT 9" Competition converter, Powerglide, 83lb inj's, Magna Flow 650HP fuel pump, 218/218 flat tapp. cam, 10mm Race Wires, Adj. FP Regulator,RJC PP ,FMIC 18x32 spearco bar&plate, Custom 3 inch mandrel DP, postons X-over pipe. deltagate WG, 3.27 gears, WB 02, 26"x9 slicks,

had similar problem on new motor and tt chip..found out that my speed-o cable was cut from welder and maf screen was out..when I replace speed-o cable and maf screen in my zo6 maf sensor -problem solved..tt chip reads mph and adjust timing according to vehicle speed..when I went back and read chip instructions it made everything clear...this maybe one area you can check...also speed-o calibration..

 

[Scott Atk]

Do you drive the car to the track? IF so chances are a 9 or 10 heat range will be fouled before you even get to the track.

 

[forcefed86]

had similar problem on new motor and tt chip..found out that my speed-o cable was cut from welder and maf screen was out..when I replace speed-o cable and maf screen in my zo6 maf sensor -problem solved..tt chip reads mph and adjust timing according to vehicle speed..when I went back and read chip instructions it made everything clear...this maybe one area you can check...also speed-o calibration..

Thanks for the idea, but I only have one timing adjustment on this chip. It was burnt for my power glide trans setup. I don't have the nice option of separate WOT timing tables per gear. Also I have my maf screen installed.

Do you drive the car to the track? IF so chances are a 9 or 10 heat range will be fouled before you even get to the track.

I can see how you would think that, and it is true on pump fuel. e85 does not foul plugs like std pump fuel. I run NGK 9 heat range in my daily driven eclipse. Plugs look great. I went to a 10 for safety purposes, the pictures of the plugs above have roughly 40 miles and 5 1/5 passes on them. Once I get the car dialed in safely I may switch to an 8 or 9. But I let the plugs tell me what the engine likes. (assuming I have the right plugs installed )

For example these 8's have 900 miles on them. I switched to 9's and they look very similar.