youll be even more disappointed.
91 upgrades,Dissapointed.
Safety Car
Joined: Dec 2004
Posts: 4,088
Likes: 0
From: Poop land
It is very easy to break the tires loose with 12 degrees base timing. With stock 6 degrees, it is just not as fun from stoplight to stoplight. I'm certain that 4-6 degrees of extra timing is at least worth 10-15 more hp as long as the coolant temps are between 160 and 180 degrees. And yes, you gotta fill her up with premium or your motor will knock to hell.
Drifting
Joined: Aug 2004
Posts: 1,430
Likes: 2
It is very easy to break the tires loose with 12 degrees base timing. With stock 6 degrees, it is just not as fun from stoplight to stoplight. I'm certain that 4-6 degrees of extra timing is at least worth 10-15 more hp as long as the coolant temps are between 160 and 180 degrees. And yes, you gotta fill her up with premium or your motor will knock to hell.
Drifting
Joined: May 2005
Posts: 1,370
Likes: 1
From: Raleigh NC
well here is the deal i have a 91 and my previous things were.cut air lid , k&n , tb bypass,cat removal ,12* timing, and borla exhaust.i took it to the strip , and made an 8.84 1/8 mile pass.i was ok with that.i bought a new set of as&m runners ,bb&k adjustable fuel pressure regulator, accel big mouth base , ported my plenum , and installed 1.6 roller rockers. i just drove it and i am so dissapointed in the way it feels, it just disgusts me.i guess those things really hurt my torque.or maybe i was just expecting to feel too much.i will know the whole tale when i go back to the strip.
I eventually went with a dyno tune on the car. If you don't have the right tune, it won't run well.
Thread Starter
Heel & Toe
Joined: Aug 2006
Posts: 23
Likes: 0
Im in liberty sc
i did not change the cam b/c i did not want to lose bottom end.the port work on the heads is just a gasket make / deburring really.the only thing we went wild on was the plenum, there was a lot of stuff in there blocking flow.do not know about the chip , lost there. it feels like it is not getting enough fuel , no matter which way i go with the regulator.i threw poundage out the window yesterday and just crunk on the screw. i turned it all the way up and it still felt like someone had a rag shoved in the tb.before it would jump sideways when it hit 2nd, now it does not even scratch, hell my wifes nissan will smoke it.if you set and let the temp get up some , it gets worse.i am getting really pissed at this thing......if some one is willing to help , i will be glad to come to you if you are not too far i feel like it is gonna tear something up.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Turn it back down to where it was before you do end up destroying your motor.
Thread Starter
Heel & Toe
Joined: Aug 2006
Posts: 23
Likes: 0
omg its getting worse!
i worked on it today till i wanted to throw something thru the windsheild. i reset the timing to 6* then checked it with the computer hooked up , and it showed 36* total.still sick , then i tried everything from 45 psi to 60 psi on the fuel, i ended up just putting it on 45 with the vaccuum off it.now it pops back like a carbureted car with a wiped camshaft , no im not kidding. i guess im gonna pull the covers and go thru the valves again. they are a little noisy , could this be triggering the anti knock? i ran them to zero , then put 3/4 turn in them with the i/c- x/o method. i am about ready to buy 5 gallons of gas and some matches
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Burning Brakes
Joined: May 2006
Posts: 1,097
Likes: 2
From: Richfield Utah
Let's not forget altitude in this discussion. You can use more advance at higher elevations. I can't remember the formula. I believe it is like 1* per 1000ft. above sea level. I am at 5500 feet ASL. We always notch our initial timing advance up to between 10*-12*. There are always plenty of variables. However, I say contain your temper, till you get it figured out, and you will figure it out... 
Last edited by Steel Breeze; Mar 6, 2007 at 08:34 PM.
Safety Car
Joined: Dec 2004
Posts: 4,088
Likes: 0
From: Poop land
i worked on it today till i wanted to throw something thru the windsheild. i reset the timing to 6* then checked it with the computer hooked up , and it showed 36* total.still sick , then i tried everything from 45 psi to 60 psi on the fuel, i ended up just putting it on 45 with the vaccuum off it.now it pops back like a carbureted car with a wiped camshaft , no im not kidding. i guess im gonna pull the covers and go thru the valves again. they are a little noisy , could this be triggering the anti knock? i ran them to zero , then put 3/4 turn in them with the i/c- x/o method. i am about ready to buy 5 gallons of gas and some matches
If you want you base timing to be accurate, you must disconnect the EST connector right near the brake booster and then start adjusting timing. You either have too much or too little spark timing. Drive with the car with retarded timing and it will feel super slow and probably backfire through the intake. Too much spark advance will cause pinging. Just a heads up...
Thread Starter
Heel & Toe
Joined: Aug 2006
Posts: 23
Likes: 0
Well..............
i found the problem.it appears someone has worked on it before(the fel pro gaskets gave it away).i do not know what was done, but i obviously did not have enough clearance for my 1.6 rr's. i have some bent valves heard it actually when i set them right , started it heard knocking for about 10 seconds then a terrible skip.so........im gonna pull it at a friends hot rod shop then build a 383 to go back. i plan on going all out and replacing the tpi with an alluminum intake and 750 mech secondary holley.
anyone interested in all the tpi junk i have now? i have all my stock equipment plus the complete after market setup i bought.my # is 864-505-3854 if i do not get a call in the next couple days, i will post this stuff elsewhere. i want to sell it all together at one time, not in pieces.if you are close , i will drive somewhere and meet you to deliver it.just call and offer what you think it is worth , be sure you have the cash because i may let it go real cheap.i have $1200 total in the after market stuff alone.
anyone interested in all the tpi junk i have now? i have all my stock equipment plus the complete after market setup i bought.my # is 864-505-3854 if i do not get a call in the next couple days, i will post this stuff elsewhere. i want to sell it all together at one time, not in pieces.if you are close , i will drive somewhere and meet you to deliver it.just call and offer what you think it is worth , be sure you have the cash because i may let it go real cheap.i have $1200 total in the after market stuff alone.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
How does rocker interference with the VC bend a valve? Pushrods sure, but I'm not seeing how it can bend valves.
Are they self-aligning rockers and bent the valve by twisting or somthing?
Are they self-aligning rockers and bent the valve by twisting or somthing?
Racer
Joined: Sep 2005
Posts: 271
Likes: 0
From: New Freedom PA
check your valve train
If you are bending or breaking pushrods , there is an obvious clearance issue in the valve train, Either your 1.6 roller rockers are causing coil bind problems at the valve springs , c valves are hiting the pistons due to excessive camshaft lift or something else.
I have seen cheap roller rocker arms even hit the edge of the valve spring retainer because they were machined improperly in taiwan or china.
I would check everything in the valve train before condeming the whole motor.
Any of the problems I mentioned would cause all the problems you mentioned earlier in this thread.
1. No power
2. Backfiring through the intake or exhaust
3. low intake manifold vacum
Desert
I have seen cheap roller rocker arms even hit the edge of the valve spring retainer because they were machined improperly in taiwan or china.
I would check everything in the valve train before condeming the whole motor.
Any of the problems I mentioned would cause all the problems you mentioned earlier in this thread.
1. No power
2. Backfiring through the intake or exhaust
3. low intake manifold vacum
Desert
Thread Starter
Heel & Toe
Joined: Aug 2006
Posts: 23
Likes: 0
fixed it
well i pushed it aside for awhile to clear my thoughts.it helped.i went thru the valves again , they were too tight
now it feels good, the changes pepped it up.cant wait to get it on the track.thx to all the replies on here it really opened my mind up some!