What my real horsepower

[ps374]

This is my first post. I own and 84 Corvette which the previous owner made some mods on. I am not sure if these mods really gained much horsepower. The car runs very good. Its not a rocket ship but it can brake the tires loose without power braking. Never had it to the track so I have no idea how to compare it with other 84s. Here is what the last owner did. He put and Xram intake with a Wealand illiminator 4bbl manifold. I had it apart because the seal was leaking on the intake and giving a high idle. The ports are much larger on the intake then the stock crossfire. He put and 85 fuel pump in the car with some kind of fuel pressure regulator and and 8746 ECM with some kind of chip which I was told was not programable. I believe the ECM is from a Camaro. He inlarged the throttle bodies, removed all polition equiment and guttted the cat with flowmaster mufflers. The car always throws a check engine light which I believe is normal with such mods. He also made the 84 hood air ducts funtional by cutting the fan shroud and sealing it with weather stripping. He also weilded the butterfly flaps in the open position. So I have several questions which i am hoping some of you guys or girls can answer. Has anyone heard of this conversion before and can anyone give me and estimate as to how much horsepower these mods may have gained?

 

[SuperBuickGuy]

You lost me at "he put an X ram manifold on the car and a Weiand intake".... two intakes on the same car?

and other questions - what does the ecm control? spark? does it have a carb?

As for hp - measure it with any of a number of iPhone or Android acceleration apps - it'll reverse calculate your hp given your et's

Pictures?

Congrats on the C4

 

[phantomjock]

Beg, borrow, or buy a data acquisition "tool."
I have the G-Tech Pro, and will give the details you are interested in.
Likewise, many apps out there for I-phone (poot-twie) or Android. [ Sorry I'm not into cr-apple products]

Or hit a Dyno. Not terribly expensive - maybe a 100 bucks for 3 to 5 pulls.

Welcome aboard - enjoy the journey here.

Cheers - Jim

 

[ps374]

The Xram is a plate that is made up of special airplane aluminum material which replaces the stock crossfire one. That plate is attached to the wealand illiminator intake whose ports are double the size of the stock crossfire intake. This plate was designed by and sold by a private person about 10 years ago. A lot of these were sold and a whole web sire was dedicated to the conversion call Cross Fire injection vault which seems to no longer be working. I have heard all kiinds of stories about the Xram producing 60 horsepower which is a myth at best. I was wondering if anyone else has this conversion and what their results were as far as horsepower gain. As far as a dyno I have seen to many blown engines on a dyno to chance that.

 

[mrvette]

Welcome to the motley crew......

Sorry I don't have much to say about your engine there, :clobbered:

 

[69427]

I've got an '84 that I've made a bunch of engine modifications to. Like to see what ya got. As a previous poster mentioned, post a few pictures so we can get a better feel for what you've got there.

Welcome to VetteMod!

 

[ps374]

I am not to good with a computer and have no idea how to post pictures but if you google Xram intake manifold under google images the first two photos are what the Xram was which is no longer made. Suppose a new replacement by another company which is suppose to give the crossfire life is available. The new intake set up is called renegade. I know nothing about it but it is suppose to exist.The crossfire was a reliable simple set up but the ports are so small very little fuel and air gets into the cylinder. I can tell you this car get plenty of fuel in the cylinder. My gas mileage is about 10 MPG. thats what the dash always says anyway.

 

[68/70Vette]

. Here is what the last owner did. He put and Xram intake with a Wealand illiminator 4bbl manifold. . The ports are much larger on the intake then the stock crossfire.

Background: I was on a tour of the Edelbrock facility and our group was introduced to their engineer in charge of cylinder head and intake manifold development. I was impressed he had a PhD from California Institute of Technology. I was putting together a ZZ4 SB engine into my 68 and it had D port exhausts. The headers I was installing were square ports. I asked him if the slight head exhaust port to heater ports was a problem.

His answer: A slight mismatch on exhaust ports is usually not of consequence because the exhaust gases are so energetic and pressure driven. What is important, he said, is the the intake manifold ports and the cylinder head ports match.
..............................
A rear wheel dyno is of course the way to measure hp, at least rwhp. A pretty good method, at least when drag strips were plentiful and convenient, was to run it in a quarter mile. I've seen long time ago a chart where you noted the mile per hour speed through the traps and the weight of the car, and the chart indicated your horsepower. It was pretty accurate. Surprisingly, the hp figure it indicated was not a function of elapsed time (ET).

Another similar thing would be to run the car at a drag strip and compare it's mph through the traps and then google for the 1/4 mile times for a 84. Compare your mph through the traps with the google'd article speed. Compare mph, not ET.