Popping under heavy throttle

v6buicks

Well-known member
Joined
Oct 22, 2018
Messages
181
Reaction score
11
Location
Franklin, IN
Hello,

I don't have a build thread so I'm going to update you now. My '02 turbo Camaro ended up getting an AEM 320LPH pump, 80# injectors, and E85. Thank you for convincing me to go big!

I tried having the car tuned by a guy who started making mail tunes his side gig. When I finally got the ECM back the car wouldn't run worth a crap and his responses were coming in as long as three days later. I gave up and called John at Intense.

Now the car runs much better. Granted, it's just a safe tune to get me by until I can get it dynod. However, I can't seem to get into boost like at all. I'm running Autolite 104s gapped at .045" and I plan to take it down to .04" to see if that makes a difference. Any other suggestions?

I have an Aeroforce scan gauge and Torque Pro, but I don't really know how to use them to their fullest potential. All I can see is that I have 0 KR which is great. Is there anything else I should look at?
 

Yaj Yak

Harbor Master
Donating Member
Joined
May 24, 2007
Messages
90,126
Reaction score
1,000
how much boost?

that gap sounds huge for a turber car
 

v6buicks

Well-known member
Joined
Oct 22, 2018
Messages
181
Reaction score
11
Location
Franklin, IN
It doesn't even need to get to 0 vacuum before it starts doing it. Right now, I have the 2psi spring in in, but I'm going to put a heavier one in it tonight, because I can hear the gate opening even at idle. lol

Good to know though. Do you think I would be safe going down to .035"? What are the side effects of having too tight of a gap? Thanks
 

SaturdaysGS

Well-known member
Joined
Jul 15, 2007
Messages
4,130
Reaction score
8
Location
Chicago (Southside)
Tighten that gap. I had to go pretty tight (.030 rings a bell) on mine for ~15ish pounds. Otherwise it would stutter (mis under high load high boost).
 

Yaj Yak

Harbor Master
Donating Member
Joined
May 24, 2007
Messages
90,126
Reaction score
1,000
yeah mine was under .030 otherwise id get blowout



worth a shot to tighten it up
 

1quick

Well-known member
Donating Member
Joined
Jan 29, 2008
Messages
19,780
Reaction score
254
Location
coal city
I, had to go down to .022 but that was on 24psi
 

1quick

Well-known member
Donating Member
Joined
Jan 29, 2008
Messages
19,780
Reaction score
254
Location
coal city
I run my coyote at .0265, there isn’t much down side to a tight gap especially if you need it to run right on the top end
 

Yaj Yak

Harbor Master
Donating Member
Joined
May 24, 2007
Messages
90,126
Reaction score
1,000
I run my coyote at .0265, there isn’t much down side to a tight gap especially if you need it to run right on the top end
i think the only thing i could think that got "different" when i dropped smaller was it would occasionally misfire at idle? :dunno:

while ago.
 

1quick

Well-known member
Donating Member
Joined
Jan 29, 2008
Messages
19,780
Reaction score
254
Location
coal city
i think the only thing i could think that got "different" when i dropped smaller was it would occasionally misfire at idle? :dunno:

while ago.
It can misfire at idle with a really tight gap I’ve never really noticed it doing that on any car, the Grand Prix did have a fairly choppy cam so it was probably hard to tell
 

Yaj Yak

Harbor Master
Donating Member
Joined
May 24, 2007
Messages
90,126
Reaction score
1,000
It can misfire at idle with a really tight gap I’ve never really noticed it doing that on any car, the Grand Prix did have a fairly choppy cam so it was probably hard to tell
mines stock so that's possibly why i noticed.
 

MonzaRacer

Well-known member
Joined
May 15, 2016
Messages
75
Reaction score
0
Location
Burns City, Indiana
My tuning experiences lately

I'll share my experiences lately.
Several local guys have picked up larger cubic engine BBC. Anything from 496 up to one guys 785 cu in and all of them from one builder and his" cnc" aluminum heads.
Well he sends Autolite plugs and claims "warranty" only if they are used.
And so far I have seen about 40 sets of Autolite plugs that are pure junk. The ONLY way to get any of them of them to work is to take new ones, gap them carefully, then bake them at 400 degrees for about two hours.
Not sure what happens but then we only get about 2 of 8 in a set being useable.
As for ability to make power I still find more and better results with AC Delco, NGK and Denso.
My preference if not using ACs I use NGK.
Also reducing gap from 060 to 050 gains decent power on NA 3800. Then remove .001"-.003" for every lb of boost
We added a pair of 101mm turbos to one 565 and ran it down to .022" .
But that engine eventually got a prototype ignition.
But I'll tell you I've been seeing a LOT of bad Autolite plugs lately. Either failing after bit of running OR dead out of box.
 

v6buicks

Well-known member
Joined
Oct 22, 2018
Messages
181
Reaction score
11
Location
Franklin, IN
Sorry for the poor focus...



All six looked pretty good.

I put the 8 psi spring in the waste gate and gapped all the plugs to .035" She scoots now! She idles just fine too. Since I noticed some smaller break-ups in certain situations, I might close them up a couple thou later. I don't plan to run boost much higher than I just did for quite a while, so I don't need to go crazy.

Damn, I'm excited! Thanks for the help everyone!
 

willizm

Ho fuckin Ho!
Joined
May 13, 2009
Messages
10,531
Reaction score
86
Location
Saint John, IN
Drop that plug gap down to .023-.025 and use some Br7’s. That will drive fine. People over think tightening the gap but the reality is you’d probably be fine even tighter than that. I’ve seen guys go as low as .017 without issue on part throttle driving.
 

willizm

Ho fuckin Ho!
Joined
May 13, 2009
Messages
10,531
Reaction score
86
Location
Saint John, IN
Sorry, BR7EF plugs. They are like $2/plug and I’d run them on e85 up to 20-22psi without a problem gapped to .022
 

Yaj Yak

Harbor Master
Donating Member
Joined
May 24, 2007
Messages
90,126
Reaction score
1,000
Sorry for the poor focus...



All six looked pretty good.

I put the 8 psi spring in the waste gate and gapped all the plugs to .035" She scoots now! She idles just fine too. Since I noticed some smaller break-ups in certain situations, I might close them up a couple thou later. I don't plan to run boost much higher than I just did for quite a while, so I don't need to go crazy.

Damn, I'm excited! Thanks for the help everyone!

:fy:

that's awesome, im glad.
 

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Top Bottom