so i have an 83 gsl, 13b 6 port swap
mods

stock port 175+k
gsl-se fueltank, pump, lines
weber 48dco carb (60f9 idle jets, 175 primaries, 160 air bleeds)
holley regulator
rb collected header and presilencer, 2.25 custom presilencer back with magnaflow
s4 lower intake manifold
no port sleeves

car made 123.8 hp ande 117.3 tq

must say im not happy with those numbers but theres room for improvement

 

We can get that motor running. Head out on the highway and look for adventure!

 

Wheel HP?........sounds about right,roughly 140 crank HP.

Hard to improve on EFI for nice round HP numbers.Carb might do better on the topend,but then again you've got stock ports.....

 

You might have done a lil better on the bottom end with working AUX ports.

 

yes thats rwhp

 

rear whel Horse power.

 

That's about normal for that motor

 

not shooting for low end power,
also my power dove after 6400rpms
ill get a scan of the dyno sheet tomorrow

 

im basing this off a friends setup which was practically identical and made 140whp and he was running a 45mm

 

Just a guess from me, but maybe you got to much carb. Ive never really messed with them on a rotary though.

 

also my friend made his peak hp an tq at the same spots i made mine at
peak hp 6400 peak tq 5200

 

well i thought that to, im sure this carb would perfom better on a street port or 1/2 bridge motor
but my engine is breathing the most it possibly can for being stock port

 

Nah the 48 should make more power!

 

why did you remove the port sleeves? from my understanding it ***** up the flow when you do that...witch makes the motor not flow as well...the whole is bigger but it does not move as much CFM

 

Like I said it was just a guess. Kinda like how 3 2barrels make more power than 2 4barrels.

 

Where did you hear that? I've never heard that! I've never seen any car run 3 2barrel carbs. when Chevy guys go huge they do 2 4barrels. not 3 2 barrels. And running w/o the sleves is way better. Just look at my dyno sheets. No loss of TQ or flow.

 

I heard it a long long time ago. Basically it has to do something with the air velocity, and that the 3 2barrels have more than the 2 4barrels. Some of the old pontiacs came this way and they were the most looked for models. Whether it is accually true or not I am not sure. I could always try and find that book that had it in it and scan up the pages.

 

Makes sense I guess, but I guess most 2 4barrel cars are charged. and we've officially stolen this thread. gr8... Well I think the big problem is tuneing and intake manifold, but that's something I'll remody this weekend. hey Rotorsex you should come over some time this weekend and we will get this taken care of.

 

Oh yeah. I apologize about the quick thread stealing.

 

meh, it keeps it at the top. gnite... LOL!!!

 

hyper, youve never seen the weber "6 packs" back in the 70s on the v8s those were the ****, not as common and redneck as a 4bbl more unique and defniatley more expensive. hahaha

ill come up, prolly tuesday or next weekend, dont get payed till monday and im dead broke

 

My '73 Z had three 2 barrels and hauled ***. Anyway....

Take a good look into your ignition. There is a lot of power to be had there. Check out the 2nd gen coil/transistor trick setup. This made a huge difference in my car, especially at the higher rpms. Normally my car would start to die off around 7k, but after the upgrade she would pull hard to 8k and beyond. Might go further than that too, but I never tried and don't want to blow my motor.

 

any vacume leaks? or does it run rich with an se pump?


Stock ignition? e fan?

 

The multicarb setups used in the early 60's Pontiacs, Olds, etc. were to compensate for the lack of a big four barrel carb. Holley didn't come out with the larger 600 cfm and up models in production cars until the real "muscle car" era kicked in. The odd shape of the runners in the multicarb manifolds make tuning notoriously difficult. They do help intake velocity at lower rpms because just one of the small dueces functions as the primary circuit, while the other two function as large secondaries. The six pack cars were more of a marketing gimmick than a real power producer. Swapping the 3 deuces for a single large four barrel is usually worth some power.

A large single barrel almost ALWAYS outperforms multiple carb setups in V8 applications. The design of the intake manifold dictates this.

Kev

 

Disappointed? That's really good for an essentially stock engine. Using a carb is hurting you a bit, and having no sleeves is *definitely* hurting you.