300 hp?
Thread Starter
Intermediate
Joined: Jun 2012
Posts: 33
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300 hp?
hey i was just wanting an estimate on how much hp my car has, inever had a chance to dyno it so id apreiciate the help, the mods i have are: accel super coil, msd cap/cap, msd wires and module, jets stage 2 chip, mickey thompson drag radials, headman headers cats removed, cold air intake with the cut lid through liscense plate/front bumber, throttle body spacer, 160 tstat, air foil. thanks
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
We need to know the year of your car for the base.
But figure everything before the headers will give you ZERO hp. Headers add 10-15 HP, no cats add 5 HP, cold air....perhaps 2 HP...and ZERO hp for everything after.
But figure everything before the headers will give you ZERO hp. Headers add 10-15 HP, no cats add 5 HP, cold air....perhaps 2 HP...and ZERO hp for everything after.
Melting Slicks
Joined: Jan 2009
Posts: 3,181
Likes: 286
From: Puyallup Washington
hey i was just wanting an estimate on how much hp my car has, inever had a chance to dyno it so id apreiciate the help, the mods i have are: accel super coil, msd cap/cap, msd wires and module, jets stage 2 chip, mickey thompson drag radials, headman headers cats removed, cold air intake with the cut lid through liscense plate/front bumber, throttle body spacer, 160 tstat, air foil. thanks
In my opinion, most of the items you list as mods will give you no, or virtually no HP gains. The only ones I see that MAY give you any gains would be the chip (depending on what it is, exactly), the headers, if they are long tube headers and not shorties, and the cold air intake.
Race Director
Joined: Apr 2003
Posts: 17,699
Likes: 1,667
From: moraga ca
You're running drag radials. Have you run it at the strip? If so, you can work backwards based on your mph to figure out your horsepower. Try the shift key on your keyboard. It probably won't make your car any faster, but your posting will be easier to read. 
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
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Le Mans Master
Joined: Mar 2004
Posts: 5,107
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From: Dublin CA
The L98 covers years 1985 up thru about 91. HP varies from year to year. What year??
So take the year with the HP rating and add about 22 HP.
Like we have said most of the things you list as modifications add ZERO HP.
Or like 383vett said, if you took the car to the track and have a MPH number for the 1/4 mile there are mathematical formulas to get you close to a HP number.
So take the year with the HP rating and add about 22 HP.
Like we have said most of the things you list as modifications add ZERO HP.
Or like 383vett said, if you took the car to the track and have a MPH number for the 1/4 mile there are mathematical formulas to get you close to a HP number.
Melting Slicks
Joined: Jul 2002
Posts: 2,223
Likes: 556
From: Tallahassee fl
on top of that, headers on an L98 don't add much without doing something to the intake.
It's all a system, you have to worry about all the ins and all the outs. The open air box for example is great... if the air didn't have to pass through peanut runners in the intake later.
It's all a system, you have to worry about all the ins and all the outs. The open air box for example is great... if the air didn't have to pass through peanut runners in the intake later.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
John Marker is right. All this stuff......is just about worthless, as "hp upgrades". In fact, the "Stage 2" chip may have taken away more than you could have gained. I agree ~+20hp for the headers and no cats.
Team Owner
Joined: Dec 2000
Posts: 21,094
Likes: 282
From: Phila., PA burbs
Years ago when my 91 was stock I bought a Jet Stage 2 chip. I took it to the track and did testing with the stock chip vs the Jet chip. If I recall correctly the stock chip was about .15 seconds quicker on average. I promptly sold that piece of garbage on ebay.
As others have mentioned, get your car to the dragstrip and you'll be able to get a pretty good HP estimate.
Safety Car
Joined: Sep 2010
Posts: 3,752
Likes: 190
From: Indiana PA
http://www.wallaceracing.com/hpcalculatorquarter.php
Inputting my data 13.38, 105, and 3350. I get about 310 flywheel HP off of MPH. Which is about right for a stock LT1.
That an my 60' needs help so the ET is a bit misleading for HP calculations.
Trap speeds generally don't lie about HP production.
Inputting my data 13.38, 105, and 3350. I get about 310 flywheel HP off of MPH. Which is about right for a stock LT1.
That an my 60' needs help so the ET is a bit misleading for HP calculations.
Trap speeds generally don't lie about HP production.
Melting Slicks
Joined: Apr 2011
Posts: 3,493
Likes: 475
From: New Jersey
The 101 Projects book talks about this at length. Most of the HP "adds" that people attempt are pure fantasy. How anyone thinks a set of wires and a cap are going to add horsepower is beyond me. How is that going to help? If it makes the car run better than what was there before all you are doing is gaining lost yardage back.
Drifting
Joined: Aug 2010
Posts: 1,704
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I agree with previous posts,only headers and cat delete make some real hp.But if you want to help that engine to breath a few more then go to intake porting, work on plenum, runners ridges and intake base ports.These are zero costs works and you can perform a good porting by yourself with basic air tools and a compressor:you tube has lots of video about this.if you want future real power heads and cam and a REAL tune based upon your engine specs.
Last edited by tunedport85inject; Mar 13, 2013 at 07:53 AM.
Instructor
Joined: Jan 2011
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From: Tulsa OK
Instructor
Joined: Jan 2013
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I can relate to your estimate of hp, I had mine dynod last week, justa quick 2 runs I was hoping 280-300hp. I got a few more bolt ons but nothin crazy, stock tune. Stock cam. Coil, rotor, cap. 1.5 roller rockers. Exhaust, delete frisbee, 9.5:1 compression(150) @ crank ported plenum, runners and base, I hauled 262hp/398trq @ 4000rpm if I remeber correctly. Numbers won't always make you satisfied but the feel will!