What mod to do first? Please read.....thanks!!
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What mod to do first? Please read.....thanks!!
A little history.
A own an 1988 L-98 4+3 with 103000 Canadian K's(62000 miles), and runs in good tune, very strong motor. I have been a fan of Corvette's for years, and have knowledge of L-98 motors, but I want to ask the experts before I do anything, because I want to do it right, with NO short cuts.
I have 2 simple mods on my car, and in my opinion has gained me modest HP gains of about 5-10 horse. The mods are a K&N filter, and a Monza Catback muffler system..........well not really a muffler system considering there are no mufflers, just a very loud somewhat euro sound, and I hate it.....too loud in my opinion, plus a rich smell sometimes.
So my question, Is what mod to do first? and how much horse approx.....I am looking about 280-300 horse to be realistic this summer without taking the heads off, or adding a cam.
I was thinking of an intake, or a good exhaust? headers? Can I just do the intake? I hear the stock one is from a 305 TPI, How much torque and horse will an aftermarket give?
please help if u can......and I was curious, if there are any police officers on this board?
[Modified by 88BlackZ-51, 11:57 PM 2/10/2004]
A own an 1988 L-98 4+3 with 103000 Canadian K's(62000 miles), and runs in good tune, very strong motor. I have been a fan of Corvette's for years, and have knowledge of L-98 motors, but I want to ask the experts before I do anything, because I want to do it right, with NO short cuts.
I have 2 simple mods on my car, and in my opinion has gained me modest HP gains of about 5-10 horse. The mods are a K&N filter, and a Monza Catback muffler system..........well not really a muffler system considering there are no mufflers, just a very loud somewhat euro sound, and I hate it.....too loud in my opinion, plus a rich smell sometimes.
So my question, Is what mod to do first? and how much horse approx.....I am looking about 280-300 horse to be realistic this summer without taking the heads off, or adding a cam.
I was thinking of an intake, or a good exhaust? headers? Can I just do the intake? I hear the stock one is from a 305 TPI, How much torque and horse will an aftermarket give?
please help if u can......and I was curious, if there are any police officers on this board?
[Modified by 88BlackZ-51, 11:57 PM 2/10/2004]
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St. Jude Donor '10
Re: What mod to do first? Please read.....thanks!! (88BlackZ-51)
Well if you hate the mufflers they should be first to go. Get flowmaster or Dynomax. Ive heard they aren't as harsh, but C4s are known for exhaust resonance.
Make sure you cut open the air filter lid and take the screens out of your MAF. Headers and catalyst removal will free up power as well, but your exhaust note will become louder. You can have a Corsa system fitted to the car and take car of that.
I wouldn't do the intake until youre ready to add a cam, then go for it.
Make sure you cut open the air filter lid and take the screens out of your MAF. Headers and catalyst removal will free up power as well, but your exhaust note will become louder. You can have a Corsa system fitted to the car and take car of that.
I wouldn't do the intake until youre ready to add a cam, then go for it.
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Re: What mod to do first? Please read.....thanks!! (SurfnSun)
thanks, I like the Corsa but they don't make it for the 88......So headers won't hurt any low end grunt?
how much horse with a good set of headers, and exhaust?
how much horse with a good set of headers, and exhaust?
Team Owner
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St. Jude Donor '10
Re: What mod to do first? Please read.....thanks!! (88BlackZ-51)
You'll have the have the Corsa's custom fitted to the car. Do you have emissions tests?
I can't say about the gains...others may know better. Id guess between 25-35hp.
I can't say about the gains...others may know better. Id guess between 25-35hp.
Race Director
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From: Lake Wylie SC
Re: What mod to do first? Please read.....thanks!! (88BlackZ-51)
I'd start with gears. As far as the engine mods go, first decide on what you want out of the engine and how much you are willing and able to spend. Horsepower costs $$$. Build you engine in packages that are already proven. I wouldn't buy a head here and a cam over there and a chip somewhere else. I'll give you an example: goto http://www.moreperformanceinc.com look under top end packages for your year group Vette. These packages work well. Other companies do the same. If this is too much $$$, then find the optimum ratio for that 4+3 and go with that. Headers and exhaust always make your Vette more efficent. Maybe a set of roller rockers. That's my dollar three eighty.
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Re: What mod to do first? Please read.....thanks!! (SurfnSun)
did not see any L-98 mods on that site?
gears? i have 3.07............the only mod i have only seen is 3.73 is mid america and ecklers........
gears? i have 3.07............the only mod i have only seen is 3.73 is mid america and ecklers........
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From: Athens AL
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Re: What mod to do first? Please read.....thanks!! (88BlackZ-51)
You dont need gears in the L98, 3.07 is about perfect.
You could get the 300hp at the crank with just exhaust work and changing to bigger runners and a better base manifold.
Hooker 2149 headers and whatever catback you like, then some AS&M Runners and an Accel/TPiS/or edelbrock base.
If you want that at the rear wheels you might need to check out the Superram.
You could get the 300hp at the crank with just exhaust work and changing to bigger runners and a better base manifold.
Hooker 2149 headers and whatever catback you like, then some AS&M Runners and an Accel/TPiS/or edelbrock base.
If you want that at the rear wheels you might need to check out the Superram.
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From: SE NY
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Re: What mod to do first? Please read.....thanks!! (88BlackZ-51)
You should see the most gains from exhaust mods; don't wory about low end loss:
-20chp from 2 1/2" front Y, good cat, good cat-back
-another 15chp from FL headers.
Toss the "frisbee" from in front of your water pump pulley for another 10chp.
Cut back the spark plug ground electrodes for 8chp gain or so.
Install an AFPR to add more fuel at WOT.
Port the plenum & upper runners to enhance air flow into the runners.
You might try the siamese intake base to increase the power band; but then a HyperTech coil/cap/rotor & good wires might be handy.
A March Power& Amp pulley set will help a little and still charge well at idle.
A 160 deg stat & aux fan switch will add 10chp or so over the stock setup.
You should get close to 300chp that pulls well to 5,500rpm of so; with 3.07 gears it should be a very sweet street ride.
BTW, what is the low (1st) gear ratio on that 4+3?
-20chp from 2 1/2" front Y, good cat, good cat-back
-another 15chp from FL headers.
Toss the "frisbee" from in front of your water pump pulley for another 10chp.
Cut back the spark plug ground electrodes for 8chp gain or so.
Install an AFPR to add more fuel at WOT.
Port the plenum & upper runners to enhance air flow into the runners.
You might try the siamese intake base to increase the power band; but then a HyperTech coil/cap/rotor & good wires might be handy.
A March Power& Amp pulley set will help a little and still charge well at idle.
A 160 deg stat & aux fan switch will add 10chp or so over the stock setup.
You should get close to 300chp that pulls well to 5,500rpm of so; with 3.07 gears it should be a very sweet street ride.
BTW, what is the low (1st) gear ratio on that 4+3?
Racer
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From: Louisville KY
Re: What mod to do first? Please read.....thanks!! (88BlackZ-51)
If you are going to spend 4 grand, why not get the fast-burn 385? $4200 buys you 385 hp/ 385 ftlbs, and you have a brand new engine. Interesting as well, add the hot cam kit and get 425 hp.
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Re: What mod to do first? Please read.....thanks!! (Chosen Won)
If you are going to spend 4 grand, why not get the fast-burn 385? $4200 buys you 385 hp/ 385 ftlbs, and you have a brand new engine. Interesting as well, add the hot cam kit and get 425 hp.
You dont get 385hp and 385 lbft after you take off their carb and put your TPI on. TPI chokes the hell out of it.
Racer
Joined: Feb 2004
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From: Louisville KY
Re: What mod to do first? Please read.....thanks!! (vader86)
Then don't put on the TPI. Sorry, hadn't seen this on previous topics. If you talk about stuff long enough, eventually you will say stuff twice.
And that's US $
http://www.gmpartsdirect.com/perform...ATID=1099.html
And that's US $
http://www.gmpartsdirect.com/perform...ATID=1099.html
Drifting
Joined: May 2003
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From: Lakeport CA
Re: What mod to do first? Please read.....thanks!! (boxerlover79)
After the cheap/freebie mods my first things years ago was exhaust (lt headers) and 1.6 roller rockers.
Made for some modest power gains for minor $ & minor tear down.
Made for some modest power gains for minor $ & minor tear down.
Pro
Joined: Dec 2002
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From: Rolling Meadows IL
Re: What mod to do first? Please read.....thanks!! (Trog)
I depends on you goals, time and money. What are you going to do with the car? Quarter mile, road race, street, drop C5's and ricers at a green light?
