is the L98 worth building up or should it be replaced
08-18-2006, 07:48 AM
#1
Instructor
Thread Starter
is the L98 worth building up or should it be replaced
i need some input fella vette owners.
is the L98 in my 85' worth a build up or should i replace it with a Crate motor.
the season is winding down and my winter brings a new project
my L98 is bone a stock TPI with 79,000 miles on it
i want more power but not looking for 500 horses of course if it was free i would take it. and my wallet can not take any major damage
so my question is
Crate motor or L98 rebuild
and yes the cheaper the project the better.
i am looking for somewhere between 350-400 HP and i would really like to keep with the TPI
(there is just something about the way the TPI's look that i like)
is the L98 in my 85' worth a build up or should i replace it with a Crate motor.
the season is winding down and my winter brings a new project
my L98 is bone a stock TPI with 79,000 miles on it
i want more power but not looking for 500 horses of course if it was free i would take it. and my wallet can not take any major damage
so my question is
Crate motor or L98 rebuild
and yes the cheaper the project the better.
i am looking for somewhere between 350-400 HP and i would really like to keep with the TPI
(there is just something about the way the TPI's look that i like)
08-18-2006, 07:53 AM
#2
It is very difficult to get 400 hp from a long tube tpi runner motor. The length of the tubes limits the max rpm. Torque is very easy (by comparison). If high hp is desired, a short runner length manifold will be needed. Back in the old days(93-94) I managed to get my 350 tpi combo to run 12.80's in the 1/4.
08-18-2006, 08:26 AM
#3
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If your just building a "fun" street vette, stay with your L98.
Don't look at HP numbers, you can get a crap load of TQ out of a L98.
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down.
TQ ROCKS!
Don't look at HP numbers, you can get a crap load of TQ out of a L98.
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down.
TQ ROCKS!
08-18-2006, 08:38 AM
#4
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It can be done. It may take a little N20 to get to the 400 rwhp.
I'm currently running about 310 hp and the wheels and 385 TQ with a well know and proven setup. Price is not to bad if you do all the work yourself.
Check out my sig.
I'm currently running about 310 hp and the wheels and 385 TQ with a well know and proven setup. Price is not to bad if you do all the work yourself.
Check out my sig.
08-18-2006, 10:00 AM
#6
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St. Jude Donor '05
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down
Took me a long time to learn this one.
08-18-2006, 10:19 AM
#7
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i'll offer a simple observation that i've sort of pieced together here now for the 4 years i've been on this board and been exposed to.
with the L98, i would draw the line at about 400chp (not rwhp) for the intersecting point to where reliability starts going south and $$ expense to get there rapidly starts accelerating. in other words, to get even appreciably hp levels will start doubling after the intial investment to get to the 400chp mark, and reliability starts being a serious issue.
just my observations after reading tons of posts for 4 years.
for an L98, i'd go with a setup that gets you to the 350-400chp mark and be very happy. you'll have very good reliability -- not far off from factory, the one-time cost will be around $4-6k (depending), and you'll definitely have SOTP crunch that far outstrips stock L98.
is is all worth it? for my first time, you bet your sweet pip. would i do it again? no -- and i'll tell you why: i would much rather have the seller do that. that way, i'm paying 10 to 20 cents on the dollar that he spent to get it there. thats a deal. i'm not an engine builder nor do i care to be, but at leats i learned enough about these cars to have a a bit if a clue as to where to go and what to do to get it solved (this forum is one great place).
edit: i didn't read the whole OP, its interesting that you desire 350-400hp, thats the right idea for a DD
with the L98, i would draw the line at about 400chp (not rwhp) for the intersecting point to where reliability starts going south and $$ expense to get there rapidly starts accelerating. in other words, to get even appreciably hp levels will start doubling after the intial investment to get to the 400chp mark, and reliability starts being a serious issue.
just my observations after reading tons of posts for 4 years.
for an L98, i'd go with a setup that gets you to the 350-400chp mark and be very happy. you'll have very good reliability -- not far off from factory, the one-time cost will be around $4-6k (depending), and you'll definitely have SOTP crunch that far outstrips stock L98.
is is all worth it? for my first time, you bet your sweet pip. would i do it again? no -- and i'll tell you why: i would much rather have the seller do that. that way, i'm paying 10 to 20 cents on the dollar that he spent to get it there. thats a deal. i'm not an engine builder nor do i care to be, but at leats i learned enough about these cars to have a a bit if a clue as to where to go and what to do to get it solved (this forum is one great place).
edit: i didn't read the whole OP, its interesting that you desire 350-400hp, thats the right idea for a DD
Last edited by Red Tornado; 08-18-2006 at 10:26 AM.
08-18-2006, 10:29 AM
#9
Originally Posted by vetster86
If your just building a "fun" street vette, stay with your L98.
Don't look at HP numbers, you can get a crap load of TQ out of a L98.
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down.
TQ ROCKS!
Don't look at HP numbers, you can get a crap load of TQ out of a L98.
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down.
TQ ROCKS!
The torque I feel is phenomenal however Hot Rod 90 has it right too! 4-6K just in motor but then there is the other while you're in there parts...like torque converter, injectors, new hoses, possibly a custom chip and the list of things goes on and on and on. Once you start it's hard to stop.
08-18-2006, 10:37 AM
#10
Burning Brakes
Induction is the biggest limitation on our L98's. Until that gets replaced, nothing else much matters in the long block (new crate motor or existing engine). You might pretty happy with just intake manifold and large tube runners and existing MAF with a cam upgrade as that should give you a very good performance increase. If you have 2.59 gears, you might also want to get down around 3.08's and a converter change. If you have cast iron heads, a decent set of aluminum heads would be a good idea (weight plus performance), plus you save the cost of valve job. All or part of this should put you deep into the 13's at over 100 in the 1/4.
Actually, 79,000 is not a lot of mileage. You might not even need a rebuilt lower end. Do a compression check and leakdown test. That should tell you the state of your rings and valves. My stock '88 lasted to 175,000 and still ran fine when I replaced it. It only had a small puff of oil smoke from valve seals leak into the combustion chambers when I first started the engine.
Actually, 79,000 is not a lot of mileage. You might not even need a rebuilt lower end. Do a compression check and leakdown test. That should tell you the state of your rings and valves. My stock '88 lasted to 175,000 and still ran fine when I replaced it. It only had a small puff of oil smoke from valve seals leak into the combustion chambers when I first started the engine.
08-18-2006, 10:39 AM
#11
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Originally Posted by Hot Rod 90
i'll offer a simple observation that i've sort of pieced together here now for the 4 years i've been on this board and been exposed to.
with the stock C4/L98 setup, i would draw the line at about 400chp (not rwhp) for the intersecting point to where reliability starts going south and $$ expense to get there rapidly starts accelerating. in other words, to get even appreciably hp levels will start doubling after the intial investment to get to the 400chp mark, and reliability starts being a serious issue.
just my observations after reading tons of posts for 4 years.
for an L98, i'd go with a setup that gets you to the 350-400chp mark and be very happy. you'll have very good reliability -- not far off from factory, the one-time cost will be around $4-6k (depending), and you'll definitely have SOTP crunch that far outstrips stock L98.
is is all worth it? for my first time, you bet your sweet pip. would i do it again? no -- and i'll tell you why: i would much rather have the seller do that. that way, i'm paying 10 to 20 cents on the dollar that he spent to get it there. thats a deal. i'm not an engine builder nor do i care to be, but at leats i learned enough about these cars to have a a bit if a clue as to where to go and what to do to get it solved (this forum is one great place).
with the stock C4/L98 setup, i would draw the line at about 400chp (not rwhp) for the intersecting point to where reliability starts going south and $$ expense to get there rapidly starts accelerating. in other words, to get even appreciably hp levels will start doubling after the intial investment to get to the 400chp mark, and reliability starts being a serious issue.
just my observations after reading tons of posts for 4 years.
for an L98, i'd go with a setup that gets you to the 350-400chp mark and be very happy. you'll have very good reliability -- not far off from factory, the one-time cost will be around $4-6k (depending), and you'll definitely have SOTP crunch that far outstrips stock L98.
is is all worth it? for my first time, you bet your sweet pip. would i do it again? no -- and i'll tell you why: i would much rather have the seller do that. that way, i'm paying 10 to 20 cents on the dollar that he spent to get it there. thats a deal. i'm not an engine builder nor do i care to be, but at leats i learned enough about these cars to have a a bit if a clue as to where to go and what to do to get it solved (this forum is one great place).
I may still do it again.
08-18-2006, 10:42 AM
#12
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Horsepower = good...
Torque = ...better!
L98's are great street engines. Remember, you must take it out of sleep mode by increasing it's efficiency. Full exhaust, upgraded fuel system, the "usuals",...
Torque = ...better!
L98's are great street engines. Remember, you must take it out of sleep mode by increasing it's efficiency. Full exhaust, upgraded fuel system, the "usuals",...
08-18-2006, 11:28 AM
#14
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Originally Posted by vetster86
If your just building a "fun" street vette, stay with your L98.
Don't look at HP numbers, you can get a crap load of TQ out of a L98.
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down.
TQ ROCKS!
Don't look at HP numbers, you can get a crap load of TQ out of a L98.
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down.
TQ ROCKS!
without a sec thought, unless u wanna be at track, i have a SR intake but sometimes i think i would have been happy with TPI setup as i dont take mine to track anyway, just want to enjoy on street and highway.
08-18-2006, 11:32 AM
#15
The VetteDr's even offer an L98 package that gets you just over 350 HP. I believe their final cost is right around $5,000 (In line with what hot rod 90 said).
I believe that's even with them doing all the work. $5K is alot, but if you end up with a new 350HP L98... it's almost worth it.
I believe that's even with them doing all the work. $5K is alot, but if you end up with a new 350HP L98... it's almost worth it.
Last edited by mikey whipreck; 08-18-2006 at 01:21 PM.
08-18-2006, 01:17 PM
#16
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C7 of the Year - Unmodified Finalist 2021
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read my website
It will be difficult to make 350-400chp with TPI on, but a modified TPI setup could do it.
It will be difficult to make 350-400chp with TPI on, but a modified TPI setup could do it.
08-19-2006, 11:49 AM
#17
Instructor
Thread Starter
i want to thank you all for your thoughts and opinions
this is why i come here
i just want more spunk outta my 85
i know the first thing to replace is the exhaust
hopefully power effects will get there #%$# together so i can get this setup
i am new to the vettes and i am a gear head by heart but dont think i have the skills to rebuild the motor myself
i have been told numerous times to throw a set of 1.6 rollers on and change the runners and plenam
i have also been told to throw on a set of long tube headers and my l98 will be awake
then i here to throw in the crate motor because the l98 is very limited. and the price for a crate will be be cheaper then a build up
my locAL vette club fellas told me to replace the ECM with a ECM and harness from a 89 vette because it has a better learning curve.
and i would love todo all that however my wallet will not allow that.
my vette's suspenstion and tranny/rear are already setup
and i will admit the power throught 1st and 2nd is nice but then it drops off
need to change that
this is why i come here
i just want more spunk outta my 85
i know the first thing to replace is the exhaust
hopefully power effects will get there #%$# together so i can get this setup
i am new to the vettes and i am a gear head by heart but dont think i have the skills to rebuild the motor myself
i have been told numerous times to throw a set of 1.6 rollers on and change the runners and plenam
i have also been told to throw on a set of long tube headers and my l98 will be awake
then i here to throw in the crate motor because the l98 is very limited. and the price for a crate will be be cheaper then a build up
my locAL vette club fellas told me to replace the ECM with a ECM and harness from a 89 vette because it has a better learning curve.
and i would love todo all that however my wallet will not allow that.
my vette's suspenstion and tranny/rear are already setup
and i will admit the power throught 1st and 2nd is nice but then it drops off
need to change that
08-19-2006, 10:58 PM
#19
Burning Brakes
Originally Posted by vetster86
If your just building a "fun" street vette, stay with your L98.
Don't look at HP numbers, you can get a crap load of TQ out of a L98.
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down.
TQ ROCKS!
Don't look at HP numbers, you can get a crap load of TQ out of a L98.
For a street car I would rather have a ton of TQ vs HP, remember TQ is what you feel when you hit the hammer down.
TQ ROCKS!
Amen, brudder-torque is something you can use anywhere!
08-20-2006, 12:03 AM
#20
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Nothing new here...
Heads/cam/intake/exhaust
or just nitrous
Don't worry about the ECM, fuel, ignition, induction, gears, or shortblock.
Heads/cam/intake/exhaust
or just nitrous
Don't worry about the ECM, fuel, ignition, induction, gears, or shortblock.