My 85 vette says it is 230HP.
I notice that it appears to be the same engine that
in later years was producing 300+ HP.
Are there simple things that can be done to boost the HP.
Why is it so low on the 85?

 

The HP is low by todays standards, but in 1985 it was the fastest production car built in the USA! 230 was the rated HP for the 85. It is the base L98 engine that over the years improvements were made. Aluminum heads were added in mid 86. Improvements to the heads etc were made in later years.

HP costs money. Your budget will determine how much HP you can squeeze out of the engine.

First, check out Vader86's web site and read it a couple of times.

The L98 responds to exhaust modifications first that can be inexpensive. If you are in a state with inspections and SMOG checks, you will be limited in what you can do. A good high flow cat, 2-1/2" front and rear "Y" pipes will help, as will a semi-stock muffler. I have had good luck with a "stock looking" muffler from Mid-America with two working outlets. Long tube headers if you can use them would really help. Many of the other mufflers on the market still do the job, but are personal choices mostly based on tone or sound.

Next you have to get the air/fuel into the engine. A free modification is to cut out the air box over the filter. The plenum, runners and intake base are next. You can port the plenum and gasket match plenum to runners and runners to intake. This will help, but there are after market set ups that are available that will flow much better. Next are a GOOD set of heads. Depending on your budget, aluminum is better than cast iron. There are good aftermarket cast iron heads out there so if your budget will not withstand the cost of aluminum go this route. If you are going to keep the bottom end (stock cam/pistons) then don't go larger than 180-190 heads. If you change out the cam, be aware that you will need a new chip.

On my base 85, I changed out the intake to the SuperRam base, SR runners and SR plenum. Went to AFR 180 heads, 1.5/1.6 roller rockers on stock bottom end. 2-1/2" front "Y", test pipe (for the track only). This combo was putting out 284 RWHP which is about 348 HP at the crank. The original 230 HP is also measured at the crank. The torque went up to about 434 at the rear wheels. This combination with 3.07 gears and automatic will put you in the mid 13's in the quarter.

Learn about the search function and do alot of reading before you jump in and start making changes. DON'T go with a off the shelf chip thinking you will add 50 HP....just won't happen.

-John

 

I also have an 85 with the base 230Hp. Been doing a lot of research on how to get to 350Hp. John is right on the money with the AFR 180cc heads. They'll bolt on approx 50Hp. You might want to look at some of the Competition Cams for TPI computer controlled engines. Once the heads can handle the flow, you'll need to open up the exhaust and intake to take full advantage. Check the TPiS website for increasing flow on the Tuned Port Injection. Their larger runners and manifold should get another 30Hp. John already mentioned the exhaust restrictions. Headers are a great add-on and can be 50 state legal. All told, you're looking at approx $5,000. Can't think of a better way to spend the money.

 

Easiest, simplest and Cheapest - bolt in an "out of the box" crate motor. Right now I'm using the "330 hp base performance" vortec head item straight from GM.

Combined with the Scoggin-Dickey intake manifold base (allowing the TPI setup to work with the Vortec heads), Edelbrock runners (and therefore a ported plenum), shorty headers and free flowing exhaust.

With the more modern combustion chamber shape and better cooling of the vortec heads (and GM's exhaust side happy camshaft that comes in this motor) you can Really play with the spark advance tables before getting into knock problems. Alternatively I've found that you can be conservative on timing and run the car happily on the cheapest (lowest octane) fuel to be found. And the gas mileage is even decent - still pulling a daily average of right at 22 mpg, with a "best" mpg in the 1500-1600 rpm range (someplace around 45-50 mph) where it will show a consistent 30 mpg....

All said and "in the car", the setup ought to be nearly the advertised 330 hp number, with something over 400 ft.lb. available. Given that this car is a 700R4, that's about enough before the "fuse" gets Too short

 

The easiest and simplest way is nitrous, not a crate motor. Most people don't like nitrous, but those same people usually don't know how it works. Their opinions are normally based on movies and what they have heard from other people who don't know what they are talking about.

My advice is to do some digging on the hows and whys of nitrous. There is no simpler, cheaper, or easier way to add power to your car.

 

How much does a brand new 330hp crate engine go for, and how much does the nitrous setup cost and how much is it to fill up a bottle with nitrous?