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Aloha C-4/5 specailist! Double Clutch again!

  • Thread starter Thread starter Da Hawaiian Punch
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Da Hawaiian Punch

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Aloha again to you C-4/5 Spec!! I have another question for you, this time it concerns may C-4. I finally got a K & N filter for my '91 after all these months. the reson for the delay was that I didnt think that it would be that much differences between that and a stock filter... which I should have known better from my past experiences with my other car after changing the stock filter out. I have two questions for you. 1st. How much of a gain should I notice in 1/4 mile times from doing this swap over? If I'm asking an invalid question, because of the lack of info, I'll try asking the question this way...how much increase in horse power and torque could I expect to gain? 2nd. With an L-98, which gear ratio would work better with this engine, a 307 ratio or a 342 ratio? I now have a stock 259 gearing and would like to change it out within the next few weeks. My driving habits are as follows... which, I know you need this info on what I want to accomplish with the rear end swap. I do want to do better on the 1/4 mile, but the car is also our only transpertation so it has to do not much worse on fuel mileage. I was told that the 307 gearing would work better with the stock L-98's power band, if any better with the 342 gearing I dont know. O.K... I lied I said two questions! actually more like 3! 3rd. How much of an improvement could I also expect by porting out the plenum box.. I mean really porting it out! cut open the runner holes to simease them ( I already have the simease runners) also the throttle body holes where the throttle body connects to (the front part of the plenum) and loosing all the the access metal inside. Mahalo again for your time and trouble...if I keep on my present course of question asking... we'll be on first name bases really soon!!!:)
 
Not that I'm a wealth of information, but I'll try and when I'm wrong or my answers need to be expounded upon, I'm sure someone with more knowledge will come to our rescue!

1) Not much, but you will feel a little more in the "seat-of-the-pants".
2) I believe the general consenus is for the use of the 3.42? 3.54.
3) Every little bit helps, these L98 really need to breath. So by opening up the plenum a little more and with larger runners you should pick up a several horses.
Next step, larger throttlebody (52mm), and a set of full length headers (shorty's won't help much more than your stockers).

Well guys, how did I do?!
 
intruder9 said:
Not that I'm a wealth of information, but I'll try and when I'm wrong or my answers need to be expounded upon, I'm sure someone with more knowledge will come to our rescue!

1) Not much, but you will feel a little more in the "seat-of-the-pants".
2) I believe the general consenus is for the use of the 3.42? 3.54.
3) Every little bit helps, these L98 really need to breath. So by opening up the plenum a little more and with larger runners you should pick up a several horses.
Next step, larger throttlebody (52mm), and a set of full length headers (shorty's won't help much more than your stockers).

Well guys, how did I do?!
Mahalo for your response intruder9. So your saying that 3.42 or 3.54 would work better for the L98 engines power band? Better than the 3.07 gearing? O.K, Mahalo again!!
 
I would like to no who lowed your car and how
it look good.
 
The 3.54 gears seem to be the general consensus of the "experienced" owners. And that is assuming you have an automatic trans.
If you have a stick, you could go to a 3.73 gear for greater acceleration with no appreciable difference in your gas mileage.
 
You really need to look at the big picture... how fast do you want your car to go in the long run? What mods are you thinking about? The reason why this is so important is you don't want to put really low-end gears on a car that has a ton of low end torque.... if you do, you will shoot right through the power-band... But, if you are planning on porting the intake, new runners, new Throttle body, maybe some head work, and a good exhaust.... then you will be sacrificing some low end torque for high end HP and the really low gears will help you out... start with the big picture, then work backwards to obtain it. Hope this helps!
 
darrellwest said:
I would like to no who lowed your car and how
it look good.
Aloha darrelwest!!! I and a buddy of mine. If you have any questions about lowering yours E-mail me at lokikalani@aol.com and we'll chat a while, or if you'd like leave your number then I can tell you step by step on how you can do yours, it's really simple, if you like to fiddle fart around with your car!!
 
intruder9 said:
The 3.54 gears seem to be the general consensus of the "experienced" owners. And that is assuming you have an automatic trans.
If you have a stick, you could go to a 3.73 gear for greater acceleration with no appreciable difference in your gas mileage.

O.K, sorry, yes I do have an automatic trans. also to VetteLT193, I do have siamiese runners, a ported out plenem will be on soon, I've gutted the center cat, and have no mufflers at this time, I do still have the other two cats on still. I do not plan on doing any head work at all, no cam change, just the usual simple average mods done to the car. I dont need to loose torque just take as much advantage of the power curve as I can, this has to be a daily driver because of it being the only car we now presently own, so gas milege is a must.... well I can sacrfice a little for performence I guess, ( hope my wife does'nt read this!!!)
 
Vettelt193 said:
You really need to look at the big picture... how fast do you want your car to go in the long run? What mods are you thinking about? The reason why this is so important is you don't want to put really low-end gears on a car that has a ton of low end torque.... if you do, you will shoot right through the power-band... But, if you are planning on porting the intake, new runners, new Throttle body, maybe some head work, and a good exhaust.... then you will be sacrificing some low end torque for high end HP and the really low gears will help you out... start with the big picture, then work backwards to obtain it. Hope this helps!
And one more thing ( I'm starting from where I left off on responing to you) I don't want to loose top end also, but want to do better on the 1/4 mile track then what car would normally do with the 2.59 gearing. I was told by a close buddy, who used to own a C-4, then desided to be a trader and get a C-5, just within days of finally convinceing me to get my C-4, because of how great these cars are (just kidding Todd!!) that the 3.07's actually work better with the normal power curve of the L-98's than the 2.59's do, in fact, not only the 1/4 mile will improve but also the top speed on the freeway, (all though we don't even nearly have enough room on this island to find this theory out) will be higher from the change. Don't get me wrong, I'm not asking this question on the forum because I don't believe my friend, but, I need some other opinions from outside before I make my choice on which gearing will next be on my... ah... sorry honey... OUR car.
 
darrellwest said:
I would like to no who lowed your car and how
it look good.
Aloha again darrelwest!! I just went ahead and copied a reply that I made to another person who asked me about lowering they're C-4. this is going to be long so if I were you if you canprint this instructions out. And if you have further questions just give me a call or E-mail me @ lokikalani@aol.com Happy lowering!!

It's so easy to do! Infact, the hardest thing to do is to cut the rubber off the spring.. that stuff on there is tuff!! Unbolt the outer tie rod & sway bar, on both sides, losen the spring retainers which is holding the leaf spring to the frame of the car. On either side that you what to start on first, get a block of wood ( 2 by 4 ) and a small floor jack will be fine, put the wood along with the jack under the spring closest to the a-arm, with out it being ON the a-arm it's self and slowly jack the spring up untill it's not resting on the lower a-arm ( about a 1/4 to an 1/2 inch off ) Disconect the ABS sensor thats located on the brake assembly, thats very important for you to do so!! ( if yours has one) remove the 2 bolts that are holding the shocks to the lower a-arm (they're located near the spring in the lower a-arm), unbolt the lower ball joint stud nut, you can use a two jaw puller or what I did was unscrew the nut untill it covered the end of the stud and with a hammer, tap on the top of the nut and not that hard or you'll ruin either the nut it's self or the stud or both. (try using a hard rubber mallet first) Before doing this, find something to put under the wheel hub.. another block of wood would be fine just to stabilize it and it should come free with no problem!! repeat this on the other side and let the presure off from the 2 by 4 and jack free and you should be able to slide the spring out from either side after you pull back at the wheel hub away little, the spring will slide out from the lower a-arm. It will not come out all the way if the car is not jacked up high enough and it does not have to!! you just need to be able to slide the spring far enough to be able to reach the rubber mounts. With a steak knife or I prefered a hack saw blade, saw off the rubber mounts and try not to cut into the spring it's self... take your time, don't rush!!. do this on both sides. this will give you the drop that your, I think looking for!!! The wheels will be, depending on what size rims you've got, if your running stock 17's will be about an 1 inch to an 1 1/4 from the fender wells, and NO!! THEY WILL NOT RUB!! You will have to of course hopefully with out saying, take the wheels off to do this job, and the ride is fine, just a little more stiff, and I do mean, A LITTLE!!
I hope this helps Aloha.
 

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