84 H.O. MODS
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From: SAN DIEGO CA
84 H.O. MODS
I REALLY CAN'T FIND A BOARD THAT FITS INTO THIS. I CURRENTLY HAVE A 1984 T/A H.O. (L69) WITH A FUNCTIONAL HOOD SCOOP AND A DUEL SNORKEL AIR CLEANER -W- K+N FILTER. I'VE ALREADY GOT AN EDELBROCK TES ON ORDER. I JUST WANT TO KNOW ABOUT CAT-BACKS THAT WORK WELL WITH THIS SYSTEM, AND ANY HEADS (I KEEP HEARING WORLD) FOR UNDER $900. ALSO, WOULD A CAM CAM SWAP AND INTAKE REALLY MAKE A DIFFERENCE WHILE REMAINING STREET (CALI) LEGAL? I JUST BASICALLY WANT TO BE A STANG/ HONDA EATER FOR UNDER $2000. ANY HELP WOULD BE APPRECIATED! P.S. I HAVE THE T-5 , SO I COULDN'T BE TOO OUTRAGEOUS WITHOUT SWITCHING THE TRANNY OUT.
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From: Philly, PA
The factory has done a lot of work for you already. The LG-4 has the most left in it stock, since it is so weak from the factory.
The headers (and y-pipe) will help out a lot. A good flowing cat-back will also help, assiming the stock cat (which is 2.75" inlet/outlet) is in good shape. Don't assume it is- the car is getting pretty old at this point.
I know you want to keep the stock air cleaner assy. cause it's a pretty cool piece but it's restrictive. An open element with a cold air kit from Air Inlet Systems (ramairbox.com) would work much better.
The factory aluminum intake manifold leaves a lot to be desired and a dirt-cheap Edelbrock Performer will be worth an easy 10-15 HP, plus retaining the EGR valve for emissions compliance.
The carb itself (computer controlled QJet) is not too bad for performance right from the factory but can be improved on by loosening the secondary air vavle tension, adjusting for full secondary opening and upgrading the vacuum break for faster secondary opeing. Shoot me an email if you want to know how to do this.
I wouldn't bother with a hotter cam unless you plan on getting some good flowing heads up top. You'd be money and HP ahead by porting the crap out of the stock heads, rather than buying new (unported) World Products castings. I speak from personal expereince on this. Ported World Products heads would be even better (but you're up around $900 by now). Others have used L-31 Vortec heads or Trick FLow Twisted Wedge heads with success but both require moderate levels of modification to make them work.
Assuming you do the heads, look for a cam with about 210-220* duration intake and exhaust, about .450-.460 lift and a tighter 110* lobe separation angle (Comp Cams 268 High Energy or 262 Xtreme Energy works very well in these motors). The stock L-69 cam is no slouch but it's still an emissions cam and can be improved on. The computer controlled carb, distributor and ECM can handle some pretty stout cams without any need for a custom chip.
End of the day (and a lot of people with suggest this) you'll go faster for less money by just dropping a mild 350 in there. All your 305 stuff will bolt right on, too. Yes, the computer controlled carb and ECM will run it just fine.
Even in California they have no way of knowing if you swap out a 305 for a 350 as long as you retian all the emissions stuff and it still blows perfume out the tailpipe.
The headers (and y-pipe) will help out a lot. A good flowing cat-back will also help, assiming the stock cat (which is 2.75" inlet/outlet) is in good shape. Don't assume it is- the car is getting pretty old at this point.
I know you want to keep the stock air cleaner assy. cause it's a pretty cool piece but it's restrictive. An open element with a cold air kit from Air Inlet Systems (ramairbox.com) would work much better.
The factory aluminum intake manifold leaves a lot to be desired and a dirt-cheap Edelbrock Performer will be worth an easy 10-15 HP, plus retaining the EGR valve for emissions compliance.
The carb itself (computer controlled QJet) is not too bad for performance right from the factory but can be improved on by loosening the secondary air vavle tension, adjusting for full secondary opening and upgrading the vacuum break for faster secondary opeing. Shoot me an email if you want to know how to do this.
I wouldn't bother with a hotter cam unless you plan on getting some good flowing heads up top. You'd be money and HP ahead by porting the crap out of the stock heads, rather than buying new (unported) World Products castings. I speak from personal expereince on this. Ported World Products heads would be even better (but you're up around $900 by now). Others have used L-31 Vortec heads or Trick FLow Twisted Wedge heads with success but both require moderate levels of modification to make them work.
Assuming you do the heads, look for a cam with about 210-220* duration intake and exhaust, about .450-.460 lift and a tighter 110* lobe separation angle (Comp Cams 268 High Energy or 262 Xtreme Energy works very well in these motors). The stock L-69 cam is no slouch but it's still an emissions cam and can be improved on. The computer controlled carb, distributor and ECM can handle some pretty stout cams without any need for a custom chip.
End of the day (and a lot of people with suggest this) you'll go faster for less money by just dropping a mild 350 in there. All your 305 stuff will bolt right on, too. Yes, the computer controlled carb and ECM will run it just fine.
Even in California they have no way of knowing if you swap out a 305 for a 350 as long as you retian all the emissions stuff and it still blows perfume out the tailpipe.
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From: GO PACK GO
Car: 83Z28 HO
Engine: Magnacharged Dart Little M 408
Transmission: G Force 5 speed
Axle/Gears: Moser 9" w/Detroit Trutrac
Well, I decided to keep the 305 H.O. I had, and I have no regrets whatsoever. I have owned a couple of 350 GM's that are slower. I did decide to change out the cam, but otherwise, it's stock. I chose the Crane Compu-cam because I still wanted a reasonable idle, with the higher lift (440-454). I am also considering the TES headers, but I see no real benifit in getting a cat-back system for these cars. It may be a single exhaust, but they are a fairly large diameter (2 1/4 I beleive). Heck, the only reason I'm considering headers are because the manifolds are slightly restrictive as compared to a tubular design.
I would, in no way, ditch the duel snorkle air cleaner. There's a reason why the newer Firebirds with the Ram-Air package are rated 20 HP above one without. Cooler outside air is more dense than the hot, underhood air it would breath otherwise. Oh, and it looks cool too.
Sure, open element air cleaners flow better, and thats a good thing since the air is hotter. I bought the K&N filter also.
Sometime in the near future, I would also like to change to a Performer as Damon recomended.
The only problem I seem to have is keeping the tires from spinning. One-Leggers Suck.
BTW, I'm not knocking Damon's opinion either. I just don't think it would take that much to beat a Honda....
[This message has been edited by Confuzed1 (edited September 16, 2001).]
I would, in no way, ditch the duel snorkle air cleaner. There's a reason why the newer Firebirds with the Ram-Air package are rated 20 HP above one without. Cooler outside air is more dense than the hot, underhood air it would breath otherwise. Oh, and it looks cool too.
Sure, open element air cleaners flow better, and thats a good thing since the air is hotter. I bought the K&N filter also.
Sometime in the near future, I would also like to change to a Performer as Damon recomended.
The only problem I seem to have is keeping the tires from spinning. One-Leggers Suck.
BTW, I'm not knocking Damon's opinion either. I just don't think it would take that much to beat a Honda....
[This message has been edited by Confuzed1 (edited September 16, 2001).]
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