3 easy mods $10 huge bang
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
yeah please take it easy on rookies like myself;that is with the money anyway..i know where the real power lies in real deep pockets,,lol..i wish i had a fraction of the money it took mod some of you guys vettes..think one of my first choices would be changing the rotating assy. for a higher revvin motor is this poss good choice or do most guys go directly to other areas like heads and computer work
Start with the exhaust. The stock 2-1/4" pipes are too restrictive. Long tube headers will give a good boost. 2-1/2" diameter pipes will help, others will tell you to use 3". I went with 2-1/2" and a Corsa cat back system.
Porting the plenum and intake and installing enlarged runners can net approx 30 Hp. The enlarged runners cost approx $450.
I found an adjustable fuel pressure regulator made a nice difference. I got one from TPiS for $69. The 85 responds quite well to an increase in fuel pressure. I increased mine from 39 to 47 psi. According to TPiS, you can see a gain of 15-30 Hp. I certainly felt the difference.
Full roller rockers can get you 10Hp. If you use 1.6 ratio for the intake, you might get a little more.
To get serious power you will need to replace the heads. The cast iron heads are woefully inadequate.
That's about the extent of what you can do without pulling the motor. Unfortunately, all this costs money. Plan on owning that 85 for a long time and do the mods as you can afford them.
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Drifting
Joined: Nov 2005
Posts: 1,324
Likes: 5
From: Charlotte NC
yeah please take it easy on rookies like myself;that is with the money anyway..i know where the real power lies in real deep pockets,,lol..i wish i had a fraction of the money it took mod some of you guys vettes..think one of my first choices would be changing the rotating assy. for a higher revvin motor is this poss good choice or do most guys go directly to other areas like heads and computer work
Pro
Joined: Apr 2008
Posts: 542
Likes: 0
From: middle of Illinois
yeah please take it easy on rookies like myself;that is with the money anyway..i know where the real power lies in real deep pockets,,lol..i wish i had a fraction of the money it took mod some of you guys vettes..think one of my first choices would be changing the rotating assy. for a higher revvin motor is this poss good choice or do most guys go directly to other areas like heads and computer work
Pro
Joined: Feb 2009
Posts: 589
Likes: 1
From: PA
I did all this to my 85. Cut the air cleaner lid and added a Kool Blue air filter, air foil, straight coupler hose between the air cleaner and throttle body, moved the MAT sensor, removed the screens in the MAF, no mufflers just straight pipes (the cat keeps it sounding like a regular car), put synthetic oil in the engine trans and rear axle. Yep I did these things when I first got mine and I'm probably forgetting 1 or 2 small things I did.
Does any of it work to an advantage? Who the heck knows. But I do think all of it works together and the car gained something good out of it. I wasn't really trying to make it faster. I wanted things to breath easier and maybe let the engine and such work a little easier. I would like to take the cat off and go with mufflers, maybe 1 day I'll do that.
Does any of it work to an advantage? Who the heck knows. But I do think all of it works together and the car gained something good out of it. I wasn't really trying to make it faster. I wanted things to breath easier and maybe let the engine and such work a little easier. I would like to take the cat off and go with mufflers, maybe 1 day I'll do that.
Thread Starter
Intermediate
Joined: Apr 2009
Posts: 41
Likes: 0
From: lake wylie sc
you guys defenitely have the knowledge and experience and i will surely follow all the advice and tips offered here.. hey,back to the t-stat results,,i'm fortunate in having many years in hardcore auto repair,,but only learned my performance mods on rotory engines,, so i only knew how to repair corvettes correctly,,but i always knew an air fuel ratio that ran 30 degrees cooler than before was a much stronger ratio ... guys,, 1 degree in temp drop in cyl head = 1hp gain..those of you who ever put the 190 back in and went for a ride can relate when they realized how much less responsive the car is
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
you guys defenitely have the knowledge and experience and i will surely follow all the advice and tips offered here.. hey,back to the t-stat results,,i'm fortunate in having many years in hardcore auto repair,,but only learned my performance mods on rotory engines,, so i only knew how to repair corvettes correctly,,but i always knew an air fuel ratio that ran 30 degrees cooler than before was a much stronger ratio ... guys,, 1 degree in temp drop in cyl head = 1hp gain..those of you who ever put the 190 back in and went for a ride can relate when they realized how much less responsive the car is
When running a cooler engine, you can run a leaner AFR and more advance to make more power, than a pig rich AFR on a hot engine.
Too many people jump on the bandwagon though, because they don't understand enough of what they are talking about. They think the temp directly equates to power.
While I don't think a 160 would be of much benefit, I use a 180 and have a good working combination. 10:1 compression ratio, a supercharger (not intercooled), 26 degrees of advance and around a 190 degree operating temperature. No knock, makes plenty of power.
The engine combo is the best thing about the car! It's the rest of the car I hate.
You can lead a horse to water but...
-- Joe
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Safety Car
Joined: Jan 2008
Posts: 3,939
Likes: 1
From: Vero Beach Florida
I call most of these Feel Good Mods either free or low cost, it also lets a first timer or novice do some things under the clamshell, do they work? do we really care? Every one knows real HP cost real $$. However it always feels good after working on your Corvette no matter what the project is, some of those are because we have to, some just because we want to. 
Thread Starter
Intermediate
Joined: Apr 2009
Posts: 41
Likes: 0
From: lake wylie sc
recently learned that all the fwd rice burners are finding ways to inject some sort of water or cooling mchanism right into their intakes to cool them down reporting major hp gain,,, not that this gives me any wild ideas,,first and foremost,,h8r of the fwds,,just sayin,,by droppin engine coolant tempts in a large capacity system such as vettes,,you truly gain more than you realize and may be giving some other mod credit ,,, i promise guys,,very pleased with the tourque and hp gain to the point i never imagined gettin this w/out spendin a grand.. took my wife out all weekend in the vette and she asked me wtf i did to the car,,, i told her i spent 10 dollars,, she said holy ----,,this thing feels scary fast from last time
Safety Car
Joined: Jan 2008
Posts: 3,939
Likes: 1
From: Vero Beach Florida
you guys defenitely have the knowledge and experience and i will surely follow all the advice and tips offered here.. hey,back to the t-stat results,,i'm fortunate in having many years in hardcore auto repair,,but only learned my performance mods on rotory engines,, so i only knew how to repair corvettes correctly,,but i always knew an air fuel ratio that ran 30 degrees cooler than before was a much stronger ratio ... guys,, 1 degree in temp drop in cyl head = 1hp gain..those of you who ever put the 190 back in and went for a ride can relate when they realized how much less responsive the car is
Thread Starter
Intermediate
Joined: Apr 2009
Posts: 41
Likes: 0
From: lake wylie sc
in response
When running a cooler engine, you can run a leaner AFR and more advance to make more power, than a pig rich AFR on a hot engine.
Too many people jump on the bandwagon though, because they don't understand enough of what they are talking about. They think the temp directly equates to power.it does.
While I don't think a 160 would be of much benefit, I use a 180 and have a good working combination. 10:1 compression ratio, a supercharger (not intercooled), 26 degrees of advance and around a 190 degree operating temperature. No knock, makes plenty of power.
The engine combo is the best thing about the car! It's the rest of the car I hate. hey there,, i actually have the luxury of watching my ecm adapt to the 30 degree drop thanks to my snap-on-scan-tool.. everything adapts to the change,,the fuel inj pulse width,,the cooler combustion temps have eliminated spark knock,,my fuel economy is signif better..the credit for this enhancement is only possible thru the cts and the aits because the ecm is designed to adapt to new conditions and the new feedback can be seen on a good scan tool..these two sensors are the only ones that actually see difference..
You can lead a horse to water but...
-- Joe[/QUOTE]
Too many people jump on the bandwagon though, because they don't understand enough of what they are talking about. They think the temp directly equates to power.it does.
While I don't think a 160 would be of much benefit, I use a 180 and have a good working combination. 10:1 compression ratio, a supercharger (not intercooled), 26 degrees of advance and around a 190 degree operating temperature. No knock, makes plenty of power.
The engine combo is the best thing about the car! It's the rest of the car I hate. hey there,, i actually have the luxury of watching my ecm adapt to the 30 degree drop thanks to my snap-on-scan-tool.. everything adapts to the change,,the fuel inj pulse width,,the cooler combustion temps have eliminated spark knock,,my fuel economy is signif better..the credit for this enhancement is only possible thru the cts and the aits because the ecm is designed to adapt to new conditions and the new feedback can be seen on a good scan tool..these two sensors are the only ones that actually see difference..
You can lead a horse to water but...
-- Joe[/QUOTE]
Thread Starter
Intermediate
Joined: Apr 2009
Posts: 41
Likes: 0
From: lake wylie sc
relocating the intake air temp sens. can poss fool the ecm negatively showing cooler air than its actually gettin will fool the ecm to thinkin it needs to increase the injector pulse width when it should be leaning due to the new rich cond. the lower temps try to create
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
recently learned that all the fwd rice burners are finding ways to inject some sort of water or cooling mchanism right into their intakes to cool them down reporting major hp gain,,, not that this gives me any wild ideas,,
,,, i promise guys,,very pleased with the tourque and hp gain to the point i never imagined gettin this w/out spendin a grand.. took my wife out all weekend in the vette and she asked me wtf i did to the car,,, i told her i spent 10 dollars,, she said holy ----,,this thing feels scary fast from last time
,,, i promise guys,,very pleased with the tourque and hp gain to the point i never imagined gettin this w/out spendin a grand.. took my wife out all weekend in the vette and she asked me wtf i did to the car,,, i told her i spent 10 dollars,, she said holy ----,,this thing feels scary fast from last time
When my cat was clogged I lost about 5 mpg. It was rattling around for a few weeks before I fixed it. It also shot a piece out the back on the highway and broke a buddies windshield that was following behind.
I'd say I was probably down at least a full second in the 1/4 from the power lost. Cat removed problem solved.
Last edited by rickneworleansla; Apr 14, 2009 at 12:07 PM.
Safety Car
Joined: Jul 2008
Posts: 3,966
Likes: 4
From: Made In America
St. Jude Donor '10-'11
Most of them are running the water/alky injection to increase boost. Here's a C4 kit.. http://www.blowerworks.net/GI.html
When my cat was clogged I lost about 5 mpg. It was rattling around for a few weeks before I fixed it. It also shot a piece out the back on the highway and broke a buddies windshield that was following behind. I'd say I was probably down at least a full second in the 1/4 from the power lost. Cat removed problem solved.
When my cat was clogged I lost about 5 mpg. It was rattling around for a few weeks before I fixed it. It also shot a piece out the back on the highway and broke a buddies windshield that was following behind.
I'd say I was probably down at least a full second in the 1/4 from the power lost. Cat removed problem solved.
That just made my day! 
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
[QUOTE=Aurora40;1569694018]I think all people are getting at is that the 160-degree t-stat and the de-screened MAF are not likely to make any or any noticeable gains.
I agree, the mind does interesting things sometimes.
I agree, the mind does interesting things sometimes.
Thread Starter
Intermediate
Joined: Apr 2009
Posts: 41
Likes: 0
From: lake wylie sc
I all but took my vette to the dyno cuz i was really impreesed after seeing how much slower the car was when i reinstalled the 190 t-stat just to make sure my mind wasnt doing one of those[interesting things]..hey,,just why do our cars feel twice as strong after the sun goes down than in the middle of a hot summer day.. physics cant be denied accuracy,,why do they sell intercoolers cuz hot air produces less hp than cooler in same atmosphere
Last edited by born2corner; Apr 14, 2009 at 01:05 PM.
Pro
Joined: Feb 2009
Posts: 589
Likes: 1
From: PA
Hahahaha, I like what Badduck just said and it's so true.
What most people don't understand is a 160, 180 or 195 thermostat is nothing more than a gate and it's designed spring weight opens at a specific temperature. That's all a thermostat is and that's all it does is open at whatever temperature it's designed to open at. Look at your 195 thermostat and look at the 160, the opening under the stopper is the same diamiter isn't it. Everyone I ever seen is. Now, with a thermostat opening at 160 or 195 in any engine passing water through the same diamiter hole, how can that make your car run cooler? It can't and it doesn't.
What most people don't understand is a 160, 180 or 195 thermostat is nothing more than a gate and it's designed spring weight opens at a specific temperature. That's all a thermostat is and that's all it does is open at whatever temperature it's designed to open at. Look at your 195 thermostat and look at the 160, the opening under the stopper is the same diamiter isn't it. Everyone I ever seen is. Now, with a thermostat opening at 160 or 195 in any engine passing water through the same diamiter hole, how can that make your car run cooler? It can't and it doesn't.