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Discussion Starter · #1 ·
are you guys still running the stock computer? I finally got someone to work my night for me and went down to the street drags last nite to see how the vette goes after all the mods. In one word CRAP. computer cut in at 5600 and killed me. ran consistant 15.21 all nite tho.:thumbsup: Every car i went up against got me 3/4 track including a porsche GT2. he was my biggest surprise.really thought he would do me on the line. Anyway i know the heads are a hold back but should i go to a aftermarket comp ?
 

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DC Crew
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Well for tunability an aftermarket computer would help. I'm not sure that's what is holding you back though. What is your full combo?

That car should run 14's stock.
 

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Discussion Starter · #4 ·
Riad ,thats what anoyed me the most,my old 88 did a 12.8 and only had the exhaust done.

one thing i found when i got home and checked what my rattle in the engine was(thought i broke pushrods again)was that i was running without fuel pressure. The vacuum pipe had burst and was'nt connected.
 

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i was running without fuel pressure. The vacuum pipe had burst and was'nt connected.
Opposite.
No vac to reg gives FULL fuel pressure all the time ; 45psi
Hi vac ( low load ); the reg cuts back the fuel pressure to 39psi

are you guys still running the stock computer? ?
Nothing wrong with stock ECM if tuned right for engine.
What mods do you have other than HSR?
 

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Discussion Starter · #6 ·
vetteoz,not much to engine. HSR.1.6 roller rockers,bit of a port /polish on stock heads,BBk t.b.Pacemaker headers .no cats twin exhaust.
3000 stall. transgo shift kit and 3.73 rear gears.

if you still have the heads and cam i will buy them off you.Have been pretty busy with the bakery and have only just been able to relax and do something with the vette.
 

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HSR.1.6 roller rockers,bit of a port /polish on stock heads,BBk t.b.Pacemaker headers .no cats twin exhaust.
3000 stall. transgo shift kit and 3.73 rear gears.
Something wrong.
Most report 50ish Hp increase and much higher revs just by bolting HSR on.
Obviously stock cam is not going to breath upstairs with increased range of intake but should be faster than stock.
The 1.6's should have given a little more breathing
How did it pull ?
5600; did it drop dead or just go flat?

Still have all the parts
Have you still got my email address?
 

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Discussion Starter · #8 ·
it pulled all the way,strong until 5600 then it got the comp chatter. i backed of but every time i went over 5600 cutouts.I set the msd rev limiter to 5800 still pulled strong to 5800 then cutout.didnt want to push 6000 as thats where it broke pushrods last time.
engine is rattleing now but p/rods are fine and still wont drive properly
 

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Check your ign. timing, try advancing it a couple of degrees.
Are you using an adjustable fuel pressure regulator?
Why do that? Why spray more fuel and advance timing all around? Some spots in the curve might not need or want it and it will back the timing down anyways. Why not have it tuned properly so that it advances as much as one part can handle and not so much at another part.

It always amazes me when people try those sort of tricks. Get the computer program for that setup and it will run right.
 

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Because some of those older ecms are not very tunable, its just an intake swap. Of corse it aint gonna be perfect but we're not talking about the spaceshuttle.Maybe the OP might see a result at the track, & it isn't gonna cost him anything. If you really want to "get a tune" rip out that harness & upgrade to the harness & ecm for the LS motors. That way you can get dis ignition too, its alot faster then any 90s or older computers.
 

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Because some of those older ecms are not very tunable, its just an intake swap. Of corse it aint gonna be perfect but we're not talking about the spaceshuttle.Maybe the OP might see a result at the track, & it isn't gonna cost him anything. If you really want to "get a tune" rip out that harness & upgrade to the harness & ecm for the LS motors. That way you can get dis ignition too, its alot faster then any 90s or older computers.
Thought 86 should be MAF and tunable? If it was an 84 crossfire, probably so. but 86 should be reasonably workable for a tuner, I would think.
 

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DC Crew
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Thought 86 should be MAF and tunable? If it was an 84 crossfire, probably so. but 86 should be reasonably workable for a tuner, I would think.
The hard part is finding people that will tune them that know what the hell they are doing. When I had my Stealth Ram and blower the "tuner" I was using wasn't worth a **** and when the opportuinity to swap to an LS came up I couldn't do it fast enough. No more tuning problems for me.
 

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The hard part is finding people that will tune them that know what the hell they are doing. When I had my Stealth Ram and blower the "tuner" I was using wasn't worth a **** and when the opportuinity to swap to an LS came up I couldn't do it fast enough. No more tuning problems for me.
Doesn't an LS also have to be tuned if you want your setup to run at optimum?
 

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Yes but it's live tuning no prom to be burned. Also it's a faster computer that sees fuel maps and timing faster.
Also not everybody got into tuning the older systems so the number of tuners who know what they are doing is limited
Everyman and his dog is tuning LSX's now ;
few of them are interested in playing with the old skool stuff , especially if it involves replacing chips
 

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Discussion Starter · #16 ·
I did not know i could use LS comp. on my 87 engine. If thats the case i will get one as like you say,even in AUST. there are heaps of guys tuning LS cars.

VETTEOZ will email you about the heads and cam,
 

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Discussion Starter · #18 ·
raid good point and excellent link.I think i will just go to carbs,when i do the head and cam i am over fuel injection.:thud:
 
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