First time out with the n20 and I give it a 50hp hit, everything seems to be OK - but I'd rather feel something alittle more dramatic. So I take her home, hook up the 75 hit and check for leaks, loose stuff all that jazz.

After I do a 3-5k 2nd gear spray - the engine starts making a funny "chop-chop-chop-chop" sound under acceleration and very quietly during idle. At idle, it seems alittle more rough and it kinda surges forward with each chop-sound. Other than that, it accellerates fine, launches fine - no other sputters or surges - just that funny sound. Any ideas?

I also have the autolie 104 gapped at .34 with an MSD 6A sparking it all.

Thanks guys.

KASR

------------------
94 Z28 Hardtop - (stock: 10.5:1, 5.7L, rated 275hp@5200, 325lb@2400, MFI - Current Rating: ???)
Throwing money at the hungry beast and moddin' away like a mad-man =) Holley CAI, !TB, !MAF, Flowmaster Catback, Monza Quad Tips, 3" cutout, 3.23 gears GU5/G80 perf. axle, QLC, 4L60-E, Spectre Breather and Filter, Autolite 103 plugs, wires, and filter, MSD 6A MODS TO COME: Jet-Hot Hooker Long Tubes, Yank 3000 TC, cc305 cam, 1.6 rockers, NX Gen II

 

I can't help you with your problem but I hope you don't break something before you get to destroy the GN, good luck my brotha


-Z

 

LOL!! Hey man, what's up!! I'm seeing you all over the net! I got plenty of time - with my luck it's something serious!!

KASR

------------------
94 Z28 Hardtop - (stock: 10.5:1, 5.7L, rated 275hp@5200, 325lb@2400, MFI - Current Rating: ???)
Throwing money at the hungry beast and moddin' away like a mad-man =) Holley CAI, !TB, !MAF, Flowmaster Catback, Monza Quad Tips, 3" cutout, 3.23 gears GU5/G80 perf. axle, QLC, 4L60-E, Spectre Breather and Filter, Autolite 103 plugs, wires, and filter, MSD 6A MODS TO COME: Jet-Hot Hooker Long Tubes, Yank 3000 TC, cc305 cam, 1.6 rockers, NX Gen II

 

I hope its nothing serious, good luck ****

 

Sounds like you may have a header gasket or collector leak.

------------------
Greg
95 Z28 conv M6
Georgia F-Body Association

Stage 1 heads, 1.6rr, Meziere WP
lt4 hot cam,lt4 timing chain kit,52mm TB,
Hooker Headers, Pro 5 shifter,3.73s,
NX 150 progressive,
Self-tuned via Tunercat

 

Just a quick thought....Did you retard your timing before running 75 shot? Sounds to me that you might be detonating(not good) due to higher timing and more nitrous. I am still confused when you say it does it at an idle though (usually detonation happens under a load). Check timing...1 degree every 25 horses.

Later

------------------
1989 Formula 350
K&N air filter, air foil, TB Bypass, AFPR (set at 45 psi), A.I.R. yanked out, Accel 8mm wires, Fireball external coil, Pulley (just the crank), gutted MAF, corvette servo, Hooker super comp. shorties, 3" exhaust all the way back, No cats, Flowmaster 40 series muffler (one in one out turned down)---Developed a bad habit....bottle related!!!!75 Shot of Nitrous
http://www.theformulasource.com/owne...php?siteid=144

So they made him get rid of it...For decency ya know....But it came back the next day...

My webpage:www.cardomain.com/id/1fastformula

 

I'll change the retard by one or two degrees and see if that helps. Also going to check all my wires - make sure I'm not missing a plug somewhere...if all else fails - take it in.

KASR

------------------
94 Z28 Hardtop - (stock: 10.5:1, 5.7L, rated 275hp@5200, 325lb@2400, MFI - Current Rating: ???)
Throwing money at the hungry beast and moddin' away like a mad-man =) Holley CAI, !TB, !MAF, Flowmaster Catback, Monza Quad Tips, 3" cutout, 3.23 gears GU5/G80 perf. axle, QLC, 4L60-E, Spectre Breather and Filter, Autolite 103 plugs, wires, and filter, MSD 6A MODS TO COME: Jet-Hot Hooker Long Tubes, Yank 3000 TC, cc305 cam, 1.6 rockers, NX Gen II

 

Possiby listen and feel around your head gaskets. Check your coolant also for any misc. debris. Goodluck!!

------------------
Denny Villemure
1989 Camaro IROC-Z Convertible, 305 TPI, 2.73 Gear, Flowmaster 2 chamber. 15.60 on motor, 14.20 on a 75 shot from NX. Woo hoo!
www.denny.cz28.com

 

I know it's a pain in the ***, but check your plugs. You may have nothing left on one of them. Also, did you go with a colder plug? Some people don't, no flame entended.



------------------
James
95 Z28 M6
-355 forged 11:1 motor and Nitrous Works Wet kit 125 shot

 

opps, guess I should read the whole thing first.... my bad.

------------------
James
95 Z28 M6
-355 forged 11:1 motor and Nitrous Works Wet kit 125 shot

 

I concur with Greg... you may have just blown out an exhaust gasket somewhere!


Good luck... hope it isn't more serious!

HInk

[This message has been edited by Redbird (edited July 31, 2002).]

 

Lucked out in a way - turns out #7 plug wire was burnt cuz the knuckleheads that installed it, put it right on the manifold!!!
(I hear that thing gets pretty hot....

Anyways, I had to go to a GM service center to find that out - so I called Tires Plus to tell them they jacked up my car and raised hell like you wouldn't believe. I told them, the first shop screwed it up - the second shop found one problem but missed another and I finally had to take it a GM service center to find out what really happened!! (I was just trying to save some time and they said they could do it - my bad!!) and the store I called was the store that tried to fix the mistake a previous Tires Plus had made. So they gave me the number for their district manager - so to make a long story short - they cover the costs of having GM take a look at it, refunded my labor costs that they charged me, and re-wired the entire car with a new set of wires (which GM quoted at $607!!!) ...heheheh...


Runs like a dream now!! LOL!!

KASR


------------------
94 Z28 Hardtop - (stock: 10.5:1, 5.7L, rated 275hp@5200, 325lb@2400, MFI - Current Rating: ???)
Throwing money at the hungry beast and moddin' away like a mad-man =) Holley CAI, !TB, !MAF, Flowmaster Catback, Monza Quad Tips, 3" cutout, 3.23 gears GU5/G80 perf. axle, QLC, 4L60-E, Spectre Breather and Filter, Autolite 103 plugs, wires, and filter, MSD 6A MODS TO COME: Jet-Hot Hooker Long Tubes, Yank 3000 TC, cc305 cam, 1.6 rockers, NX Gen II

[This message has been edited by KASR_Z28 (edited July 31, 2002).]

 

I'm glad to hear it's running good again bro.
Have you run a bigger shot than the 75 yet?

 

Going 100 and then 125 this week...let's see how it goes.

KASR

------------------
94 Z28 Hardtop - (stock: 10.5:1, 5.7L, rated 275hp@5200, 325lb@2400, MFI - Current Rating: ???)
Throwing money at the hungry beast and moddin' away like a mad-man =) Holley CAI, !TB, !MAF, Flowmaster Catback, Monza Quad Tips, 3" cutout, 3.23 gears GU5/G80 perf. axle, QLC, 4L60-E, Spectre Breather and Filter, Autolite 103 plugs, wires, and filter, MSD 6A, Compucar n20 125 MODS TO COME: Jet-Hot Hooker Long Tubes, Yank 3000 TC, cc305 cam, 1.6 rockers.