CorvetteForum - Chevrolet Corvette Forum Discussion

CorvetteForum - Chevrolet Corvette Forum Discussion (https://www.corvetteforum.com/forums/)
-   C4 Tech/Performance (https://www.corvetteforum.com/forums/c4-tech-performance-48/)
-   -   LT1 Heads on L98 (https://www.corvetteforum.com/forums/c4-tech-performance/1875788-lt1-heads-on-l98.html)

lumij3 11-29-2007 12:16 PM

LT1 Heads on L98
 
Is there any advantage in changing the L98 heads for LT1 heads. If so, what's the advantage and can I do it easily?

LJ

ToniH 11-29-2007 12:48 PM

No and no.

vader86 11-29-2007 12:49 PM

Nope. next idea.

lumij3 11-29-2007 01:08 PM

thanks. What would be a nice set of heads and cam for a l98 with ported runners and plenum, 52mm tb, street runner ship, open air filter, corsa exhaust sys.? I used to owned a 2001 cobra it made 350 hp, and I would like to get the same rush when driving my vett.
lj

ToniH 11-29-2007 01:49 PM

AFR Eliminators 180cc are nice heads for your application.

You might need to do a bit more on the intake parts to get the 350hp feeling you seek. I mean there is lots of nice cams but the intake might be restricting you. At least port the heck out of the base plate if you are not interested in upgrading the TPI. When your intake is sorted you can choose the cam. Crane, LPE and even GM have many good options.

PS. what year is your car? You might need to get a engine specific chip made to get everything out of it and to make sure it works ok.

PS2. also rear end mods and a good torque converter will help and might even be cheaper than the engine mods.

redrose 11-29-2007 01:54 PM


Originally Posted by lumij3 (Post 1562954515)
used to owned a 2001 cobra it made 350 hp, and I would like to get the same rush when driving my vett.
lj

'stangs are oem trans/rear axle geared for 1/4 mile, vettes are oem geared for insane top end/ cafe fuel consumption...you choose.

lt1 heads have been installed on the sbc1 block, not really worth the gymnastics...the lt1 intake modded to fit sbc1 (L98) heads/block rocks.

vader86 11-29-2007 01:57 PM


Originally Posted by lumij3 (Post 1562954515)
What would be a nice set of heads and cam for a l98 with ported runners and plenum, 52mm tb, street runner ship, open air filter, corsa exhaust sys.?

Your stock heads, ported.

LPE 211 or TPiS ZZ-9 camshaft.

Then a custom chip, toss the streetrunner junk.

lumij3 11-29-2007 02:26 PM


Originally Posted by ToniH (Post 1562954980)
AFR Eliminators 180cc are nice heads for your application.

You might need to do a bit more on the intake parts to get the 350hp feeling you seek. I mean there is lots of nice cams but the intake might be restricting you. At least port the heck out of the base plate if you are not interested in upgrading the TPI. When your intake is sorted you can choose the cam. Crane, LPE and even GM have many good options.

PS. what year is your car? You might need to get a engine specific chip made to get everything out of it and to make sure it works ok.

PS2. also rear end mods and a good torque converter will help and might even be cheaper than the engine mods.

It is a 1988 conv. By rear end mod do you mean Dana 36 with 3.73 ring and pinion? Also when talking about a good torque converter what would be your sugestion? Thanks again
lj

lumij3 11-29-2007 02:27 PM


Originally Posted by vader86 (Post 1562955125)
Your stock heads, ported.

LPE 211 or TPiS ZZ-9 camshaft.

Then a custom chip, toss the streetrunner junk.

Yes, stock heads ported to the max without siamesing.

lumij3 11-29-2007 02:29 PM


Originally Posted by redrose (Post 1562955066)
'stangs are oem trans/rear axle geared for 1/4 mile, vettes are oem geared for insane top end/ cafe fuel consumption...you choose.

lt1 heads have been installed on the sbc1 block, not really worth the gymnastics...the lt1 intake modded to fit sbc1 (L98) heads/block rocks.

better or equal to Accel Super Ram?

lumij3 11-29-2007 02:35 PM

Add to this equation headers, Do they make any difference when trying to gain torque and hp.?
LJ

ToniH 11-29-2007 02:47 PM

- 3.73 too high for L98 and automatic transmission. 3.07 better.
- for modified L98: 2600-2800 stall tc. Search for tc threads by PeteK
- LT1 intake vs. SuperRAM - which is better? not comparable at same rpm, do a search, >24000 threads about them.
- headers: yes very good for L98. Search for hookers, stainlessworks.

vader86 11-29-2007 03:01 PM

An 88 with this setup would need 2200-2400 rpm TC, if driven alot....if a drag only car go a couple hundred rpm higher.

3.73 wayyyy too low a ratio for this setup. Needs 3.07, nothing lower.

Headers=always.

Once you start talking about changing to LT1/MR or SR, then everything has to be reconsidered from scratch. If you want to optimize it for right now, then do what we've suggested. More is on my website, click my name.

ToniH 11-29-2007 03:17 PM

:rofl: too high / too low - well we mean the same anyway :)

lumij3 11-29-2007 04:15 PM


Originally Posted by ToniH (Post 1562955903)
- 3.73 too high for L98 and automatic transmission. 3.07 better.
- for modified L98: 2600-2800 stall tc. Search for tc threads by PeteK
- LT1 intake vs. SuperRAM - which is better? not comparable at same rpm, do a search, >24000 threads about them.
- headers: yes very good for L98. Search for hookers, stainlessworks.

Thank you for your help.

LJ

lumij3 11-29-2007 04:17 PM


Originally Posted by vader86 (Post 1562956083)
An 88 with this setup would need 2200-2400 rpm TC, if driven alot....if a drag only car go a couple hundred rpm higher.

3.73 wayyyy too low a ratio for this setup. Needs 3.07, nothing lower.

Headers=always.

Once you start talking about changing to LT1/MR or SR, then everything has to be reconsidered from scratch. If you want to optimize it for right now, then do what we've suggested. More is on my website, click my name.

Thank you for your help.

LJ

Orr89rocz 11-29-2007 10:47 PM

LT1 heads have more material on them and can be ported to near 290cfm. L98 heads seem to cap off at 250-260 from what i've seen.

BUT then again for the amount of work you will do to the LT1 heads to get them to work, then portwork involved, if you cant do any of that yourself, you can get AFR eliminators for 1450 and flow 280ish cfm out the box so it will make power.

but they are generally overkill if your not looking for big power and big cams. BUT even with smaller cams its good to have more head flow than anything. As long as your intake can flow the cfm needed for your hp goals

lumij3 11-30-2007 03:09 PM

As I am trying to calculate how much is all this going to cost I am coming to nearly 6K and that is doing all the work myself. The q? is: Is this worth it in a '88 corvette or should I try to sell it plus the 6 grand that I would use to try to make decent torque and hp and buy another year like in the '90s that comes with at least 300hp? Did I buy the wrong year?
LJ

redrose 11-30-2007 03:32 PM


Originally Posted by lumij3 (Post 1562970249)
Did I buy the wrong year?
LJ

nope...you have one of the best.

trash the tPi and put just an lt1 intake on and you have 300 hp, other mods when you need more.

Corvette Kid 11-30-2007 06:43 PM


Originally Posted by vader86 (Post 1562956083)
An 88 with this setup would need 2200-2400 rpm TC, if driven alot....if a drag only car go a couple hundred rpm higher.

3.73 wayyyy too low a ratio for this setup. Needs 3.07, nothing lower.

Headers=always.

Once you start talking about changing to LT1/MR or SR, then everything has to be reconsidered from scratch. If you want to optimize it for right now, then do what we've suggested. More is on my website, click my name.

If you get your HP peak up to near 6K or so, you'll want to consider more converter, even for a street car. I use a 3000 stall Vigilante on the street and while they're admittedly pricey, it drives like a stocker in normal driving. Plus, it saves about 17 lbs. of rotating weight over a stock sized converter. That's a big plus in power, the speed at which the engine wraps up and in overall efficiency.


All times are GMT -4. The time now is 02:23 PM.


© 2024 MH Sub I, LLC dba Internet Brands