88RS

iTrader: (7)

Were these engines the same? Searching leads me to believe they are, but driving them they felt entirely different. We used to have these vehicles years ago, and the extended cab 2wd truck with an automatic felt a lot more powerful than the lighter Camaro with the 5 speed. Is it just that the air cleaner assembly is THAT bad on the third gens? Or is there more to it? I think the truck had 2-1/2" exhaust vs the 2-1/4" on the Camaro, so there was that.

Something I have been wondering about since I started cutting up the tbi air cleaner off my 92 parts car for cowl induction use... Admittedly never paid much attention to the truck's though. Thanks.

NoEmissions84TA

iTrader: (1)

Subscribed because I still have my 1995 GMC 305 TBI extended cab 4wd truck with an automatic.

Schurkey

What was the axle gear ratio of the 1500 vs. the axle ratio of the Camaro?

A TH700/4L60E has a deep first gear plus torque converter multiplication. The 5-speed has no added torque from a converter.

dmccain

iTrader: (2)

The truck L03 has a flat tappet cam and the car has a roller cam. Both cams are equally as pathetic as the other. The car may make 10-15 more HP but is definitely more restricted by a **** poor stock exhaust system. Trucks exhaust should be a lil better.

88RS

iTrader: (7)

The Camaro had a 3:42 axle swapped into it. I have no idea what the ratio was in the pickup truck. Just with the weight and shorter tire alone, one would think the Camaro would have waxed the truck. We never did get the two next to each other, but sotp said the truck was a lot quicker. Perhaps the miles and bad valve seals played a bigger role in the car's asthmatic performance than I initially thought too, and the cat may have been clogged.

I was mainly investigating the stock Camaro lo3 air cleaner and seeing it as one of the main differences between the vehicles. I never have taken a close look at the truck's air cleaner either. I definitely think there is more to the story now with how that car ran, but I can't believe how terrible the f-body air cleaner is. It's like everything that was well known about air traveling into a carburetor was totally disregarded in creating it.

aliceempire

iTrader: (14)

I'm not saying the air cleaner is great for performance but I had a cammed L05 in my 92 at one point. It had headers and better than stock exhaust on it too. With either the standard air cleaner lid or the 82-84 HO lid that got air from the power bulge hood it made no difference on street or at the track. Leading me to believe the power bulge air cleaner added nothing or the L05 wasn't taxed by the air cleaner by much if at all. If it wasn't the air cleaner being a restriction then I doubt it has any effect on the lowly L03. But I also have no proof that the HO air cleaner added anything to speak of.

dmccain

iTrader: (2)

The cars L03 must have been in bad shape. I could see a Vortec 305-350 truck being stronger but with 3.42 gears and the same engine the car should have been WAYY quicker than the truck. I remember outrunning every L05 showtruck I ran back in the day with my old LG4 Formula even when it was stock. The car L03 was definitely stronger than the truck L03 if they are running right.

TransamGTA350

iTrader: (2)

Back in 1994, my Dad owned at the same time 1994 GMC 4wd pickup with an L05/auto and a 1992 Camaro RS with an L03/auto. Even with the truck having a 350, the Camaro was definitely faster.

dmccain

iTrader: (2)

Took an LB9 out of my 87 T/A and put over in an 87 Chevy Truck that had the L05. That truck was stronger with the LB9 than it had been with the L05 powered 350. But as we know an LB9 was definitely stronger to begin with than the L03.

88RS

iTrader: (7)

That pretty much confirms it for me guys, that Camaro lo3 had something wrong. Likely heavy deposits on the valves, maybe plugged cat as well. I remember driving it and not being able to even scratch 2nd.

So you were only using the lid with the hole in it attaching to the bulge with the f-body lo3 air cleaner base? I think the lo3 base itself is where all the problems are at.

NoEmissions84TA

iTrader: (1)

It's the snorkel being reduced down to the size of a drinking straw.
You can add a 2nd snorkel.
https://www.thirdgen.org/forums/carb...l-snorkel.html
https://www.thirdgen.org/forums/tech...-housings.html

88RS

iTrader: (7)

I agree, but that's not all. The one on my parts 92 Camaro has a cylinder that extends up from the tbi pretty close to the lid. It forces all incoming air to come straight in from the top and around the injectors. Air flow through the short filter to this cylinder is making some funky turns to get up there, and there isn't a lot of space.

I have a 4" cowl hood on my current 88 Camaro I'm planning to make use of. Plan is to cut the floor out of the stock base and weld in an aftermarket base, doing away with the spacer underneath as well so air can flow in from the sides of the injectors. I'll also fill in the snorkel hole. I cut the edge of the stock lid back to the filter, and bought 2 different 12" Wix air filters for a 95 Chev c1500 on Rock Auto. One is 3-1/2" tall, other is 5". The hood opening is centered, the engine in chassis is not so I'll need to offset stock base somewhat before welding to the aftermarket base to get a good hood seal. Likely won't use the 5" tall filter but it might come in handy for fitment. I'm sure I'll come across issues along the way, but this is the plan.



Wix 42098

Wix 46220


Minor progress

If anyone know where to get a 1988 "FUEL INJECTION" decal for it, I'd love to get one.

dmccain

iTrader: (2)

Check with "Hatfields Decals" on Etsy, she made me some very nice custom decals for my car.

Schurkey

So now you've got either an open-element air cleaner, pulling in hot engine compartment air, or you've got a cowl-induction hood spilling cool, high-pressure air into the engine compartment, reducing air flow through the radiator.

I don't see either one as a net benefit.

Cowl hoods MUST be SEALED to the air cleaner using rubber seals, or foam gaskets--something has to prevent the cowl air from blowing into and around the engine compartment. The "cowl air" needs to be directed into the air cleaner, and nowhere else. It's how the OEMs did it, and they did it for a reason. Even non-cowl-induction hoods had a rubber seal at the windshield area, to prevent high-pressure air from being blown forward into the engine compartment.

88RS

iTrader: (7)

Thanks for the recommendation! I saw some Firebird decals in there, did you create the designs?

I am aware. Please read post #12 as it seems to me that you have only looked at the picture. This is still a work in progress. At this point I think the only thing I'm in the clear to do with it is cut off the snorkel and weld a piece in to block it. The other engine isn't in the 1988 Camaro yet, and it's getting a Vic Jr 2 barrel with an adapter and polyurethane engine mounts, so I don't trust any measurements I'd get off the stock 220k mile 1992 parts Camaro that the unfinished air cleaner is sitting on in the picture.

Fast355

iTrader: (2)

My factory 94 G-van had a 305 roller motor the way it came from GM and atleast in the vans was rated more hp and more torque than the F-car version. Vans of that era had 2 1/4" exit under the spark plug log manifolds that flowed alot better and a larger y-pipe. With the 3.73 G80 it was a good bit quicker than a LG4 or L03 F-car under 50 mph or so.

88RS

iTrader: (7)

Well, I was at the junkyard yesterday looking at the tbi truck air cleaner base. The air cleaner base the lo3 f-bodys got is a total joke by comparison. The truck base I looked at didn't have that silly ring welded into it, and air had a more direct path to the throttle body from the filter, along with a much bigger snorkel opening and a taller filter. It makes sense to me why so many guys on here have been happy with their aftermarket open elements sucking in hot engine bay air.