need more hp for my 74

[TRAVIS74]

I was hoping someone could suggest a good setup for a 195 horsepower L-48. I am looking for around 300 horsepower.
I am a novice mechanic at best and was hoping there was a simple fix. Any suggestions would be appreciated. The engine I have is completely stock. I was thinking a cam and carburator would do the trick. Thanks Travis

 

[rgtrough]

more horses

Hey Travis, there are some very basic things you can do to your car to improve performance. Don't be swayed by the propaganda that the advertising mopes add to every so called performance part. Very few bolt-on items will add 10-15 rwhp. Figure out what you want out of your engine and start calling manufacture tech lines and posting questions on forums like this. The only dumb question is the one you won't ask. A good start is a matched combination of intake manifold, carb, and cam that will go with the heads you will be using. There is no use in putting on big time racing parts if you don't match things up. Headers and low restriction mufflers are also a must. There are many very knowledgable people here at CAC that are more than happy to help. Have fun dude.:cool
Bud

 

[MoeJr]

Keep the QJet carb as it is a great fuel mixer when properly set up. I would like to see an Edelbrock Performer Intake and a good exhaust system of 2.5 inches and appropriately sized headers. I did not notice whether car was Automatic or Manual Trans so with Cam selection I would go with a Cam with 214-224 Duration at .050 on the intake and use a dual pattern cam for wider powerband and a 2400 Stall converter if it is automatic. Now it probably has 3.08 gears in the rear so I would probably go with 3.55's with 27.4 inch tires which would be about the stock size(225/70R15). A shift kit in trans would be good and have it set up for Full throttle shifts to occur at 5500-5800 which will be about 400-900 rpm higher than the hp peak.Also instead of buying heads you can have yours given a mild polish and port job and smooth under the valves for better flow. This should help you get close to the magic 300 net hp mark about 250 rear wheel. Hope this helps.

Moe

 

[Jack]

Plan, Do, Check, Act

Travis:
Welcome aboard CACC! 74 split-tail’s are cool!
For most street cars a good Qjet is hard to beat ... keep it, repair if need be.
Horsepower & Torque are often misunderstood. What most street rodders actually want is “useable power” ... and that equates to a long, flat torque curve. Horsepower becomes more important in drag racing.

Start with the basics: verify what you have and formulate a plan from there.

First, verify that your jurisdiction has no practical prohibition of modifying your year car ... and verify that any changes you might make will not prevent you from passing any smog/emissions testing your jurisdiction may (or may not) have.

Next, verify what you have: note axle ratio, pull valve covers and note head casting numbers, note which transmission you have, headers or cast iron, note any current engine-driveline mods. Knowledge of this will help get more reliable answers from both suppliers and forums.

Go get yourself a dial back timing light ... it’ll quickly become a valued companion.

Verify condition of your motor & driveline before hopping it up. Check & note compression on all 8 ... & any unusual oil/gas consumption. Verify oil pressure w/ a second gage. Map out & note your ignition timing curve ... to identify if distributor advance is faulty & id any slippage in harmonic balancer/damper ... an improved curve can easily add 20hp/tq for next to nothing$. Visually inspect the distributor’s internals closely; verify both vacuum & mechanical advance are in good condition & operate freely.

You can do it! Done with moderation an intake, cam & a little headwork will easily get you an obvious increase of reliable, street-friendly, pump gas-friendly “useable power” for under $750 ... probably exceed your goals for even less$.
JACK:gap