L98
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 112
From: Michigan
Increasing the plenum volume and lowering temp is a big deal. Stock ignition & valvetrain are junk!
Change the cam & intake and you have the early zz engine and what are they rated for? Now add accessorys, cats, poor exhaust, the tpi intake in stock form.
Change the cam & intake and you have the early zz engine and what are they rated for? Now add accessorys, cats, poor exhaust, the tpi intake in stock form.
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
I always though the stock ignition was fine. Reliable and perfectly capable of handling large hp numbers.
Team Owner
Joined: Jul 2004
Posts: 28,378
Likes: 3,261
From: Hartford WI
Cam, intake, heads change requires computer tuning which you don't have. I'd love to see you hook up the ZZ4 engine to your ECM and see what it will do or won't. You don't make the same lift and if you did, the ECM probably will freak out. You can't make that ZZ4 power (355 HP) on the stock tune. I don't think GM put the Vette on a Chassis Dyno to get 240HP. I would suspect it was on an engine dyno since that is the most impressive without all the stuff on it.
See below excerpt from Summit Racing. Tell me exactly what you have that equals that:
The aluminum angle-plug cylinder heads have screw-in rocker studs, 1.94 in. intake and 1.50 in. exhaust valves, and 58cc combustion chambers that yield a crisp and responsive 10:1 compression ratio. Also included are lightweight valve spring retainers, radiused valve seats, and valve stem seals to help keep the oil where it belongs. To complement the cylinder head design, we've incorporated a billet steel hydraulic roller tappet camshaft with a .474 in. intake and .510 in. exhaust valve lift. The combination makes 355 hp at 5,250 rpm
Last edited by aklim; Dec 3, 2015 at 03:30 PM.
Team Owner
Joined: Jul 2004
Posts: 28,378
Likes: 3,261
From: Hartford WI
Works for my 383. I had to change to the small cap distributor because of the HSR but it did supply the power needed in my F-body before the transfer to the Vette.
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 112
From: Michigan
That's one of the reasons I haven't changed the cam or done any major mods and this is a MAF car.
I still use the stock dist just I do a lot to the ignition in general. I've listed some of them before but I'm not bored enough to go over all the details LOL
edit: A good engine builder could take apart that crate engine mod the parts, change some small stuff, but not change the cam or port the heads and pick up more HP. Still a great engine would already have ported heads and the right cam.
edit2: I want to be clear since we have hijacked this thread to debate on my ET based rwhp claim. I did not suggest the OP do what I have done nor do I expect him to know all the stuff I know. I only suggested he could get 300rwhp with the right cam, exhaust, intake and not heads. You can clearly see my point by looking at the zz engines. Of course more HP should be expected with good heads and how much more is based on skill/effort and combo match.
I still use the stock dist just I do a lot to the ignition in general. I've listed some of them before but I'm not bored enough to go over all the details LOL
edit: A good engine builder could take apart that crate engine mod the parts, change some small stuff, but not change the cam or port the heads and pick up more HP. Still a great engine would already have ported heads and the right cam.
edit2: I want to be clear since we have hijacked this thread to debate on my ET based rwhp claim. I did not suggest the OP do what I have done nor do I expect him to know all the stuff I know. I only suggested he could get 300rwhp with the right cam, exhaust, intake and not heads. You can clearly see my point by looking at the zz engines. Of course more HP should be expected with good heads and how much more is based on skill/effort and combo match.
Last edited by BOOT77; Dec 3, 2015 at 04:35 PM.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
That is true. Nothing wrong with the stock ignition for most applications. NO power to be gained there.
Team Owner
Joined: Jul 2004
Posts: 28,378
Likes: 3,261
From: Hartford WI
That's one of the reasons I haven't changed the cam or done any major mods and this is a MAF car.
I still use the stock dist just I do a lot to the ignition in general. I've listed some of them before but I'm not bored enough to go over all the details LOL
edit: A good engine builder could take apart that crate engine mod the parts, change some small stuff, but not change the cam or port the heads and pick up more HP. Still a great engine would already have ported heads and the right cam.
edit2: I want to be clear since we have hijacked this thread to debate on my ET based rwhp claim. I did not suggest the OP do what I have done nor do I expect him to know all the stuff I know. I only suggested he could get 300rwhp with the right cam, exhaust, intake and not heads. You can clearly see my point by looking at the zz engines. Of course more HP should be expected with good heads and how much more is based on skill/effort and combo match.
I still use the stock dist just I do a lot to the ignition in general. I've listed some of them before but I'm not bored enough to go over all the details LOL
edit: A good engine builder could take apart that crate engine mod the parts, change some small stuff, but not change the cam or port the heads and pick up more HP. Still a great engine would already have ported heads and the right cam.
edit2: I want to be clear since we have hijacked this thread to debate on my ET based rwhp claim. I did not suggest the OP do what I have done nor do I expect him to know all the stuff I know. I only suggested he could get 300rwhp with the right cam, exhaust, intake and not heads. You can clearly see my point by looking at the zz engines. Of course more HP should be expected with good heads and how much more is based on skill/effort and combo match.
Feel free to point out the post because I am curious how much you can do to a stock ignition to make a significant difference to a well functioning stock ignition system.
More, yes. Even if you gain 1 HP, you can call it "more". Again, what is the definition of "more"?
Hell with the ZZ engines. They have different heads and cam and intake so you have your apples and they have their oranges. Feel free to edumakate us on how to take a perfectly functioning L98 vette and make 100 HP more with bolt ons and a cam. Dyno sheets would be interesting. Butt dyno is meaningless.
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 112
From: Michigan
LOL you just don't get it, the power was already there! Prob wouldn't believe me if I told you certain coils like diff rpm ranges.
I did say early zz engines and from what I've seen the smaller 350 size(the size I'm talking bout) used the same cam for awhile. Headers & exhaust are know improvers, people have swapped out the stock zz cam for improvement alone on the zz engines with the same heads(find one of those cams), it's also well know a good intake pick ups decent. Add it up 100hp isn't a stretch from a matched combo. Then tune it with. People constantly go overboard with one of those(usually headers & exhaust 1 3/4 & dual 3") and ruin potential.
I don't even care bout the dyno I care bout real world and being out front of the other car.
I did say early zz engines and from what I've seen the smaller 350 size(the size I'm talking bout) used the same cam for awhile. Headers & exhaust are know improvers, people have swapped out the stock zz cam for improvement alone on the zz engines with the same heads(find one of those cams), it's also well know a good intake pick ups decent. Add it up 100hp isn't a stretch from a matched combo. Then tune it with. People constantly go overboard with one of those(usually headers & exhaust 1 3/4 & dual 3") and ruin potential.
I don't even care bout the dyno I care bout real world and being out front of the other car.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Team Owner
Joined: Jul 2004
Posts: 28,378
Likes: 3,261
From: Hartford WI
LOL you just don't get it, the power was already there! Prob wouldn't believe me if I told you certain coils like diff rpm ranges.
I did say early zz engines and from what I've seen the smaller 350 size(the size I'm talking bout) used the same cam for awhile. Headers & exhaust are know improvers, people have swapped out the stock zz cam for improvement alone on the zz engines with the same heads(find one of those cams), it's also well know a good intake pick ups decent. Add it up 100hp isn't a stretch from a matched combo. Then tune it with. People constantly go overboard with one of those(usually headers & exhaust 1 3/4 & dual 3") and ruin potential.
I don't even care bout the dyno I care bout real world and being out front of the other car.
I did say early zz engines and from what I've seen the smaller 350 size(the size I'm talking bout) used the same cam for awhile. Headers & exhaust are know improvers, people have swapped out the stock zz cam for improvement alone on the zz engines with the same heads(find one of those cams), it's also well know a good intake pick ups decent. Add it up 100hp isn't a stretch from a matched combo. Then tune it with. People constantly go overboard with one of those(usually headers & exhaust 1 3/4 & dual 3") and ruin potential.
I don't even care bout the dyno I care bout real world and being out front of the other car.
100 is a stretch without tuning from a stock engine unless you are replacing something that was broken
Dyno removes bias and driver ability. I could be pulling ahead of my Grandma even if she were driving my car because she doesn't dare to push it hard enough. Dyno proves you got whatever gains you say you got or proves you imagined it. Pulling ahead of the other car only proves you are driving faster than the other guy. Huge difference.
Team Owner
Joined: Jul 2004
Posts: 28,378
Likes: 3,261
From: Hartford WI
I had no idea we were shifting to NASCAR and what the potential of their engines are. I thought we were talking about the L98 in the Vette and specifically what real evidence you were bringing to the table instead of speculation and butt dyno feelings. 
I mean, if we talk about what my butt dyno thinks my car is making, I'd have to guess at 800 HP, possibly 950. And today, till midnight, I have a bridge for sale. One previous owner, slightly used and well maintained. Cash only.
I mean, if we talk about what my butt dyno thinks my car is making, I'd have to guess at 800 HP, possibly 950. And today, till midnight, I have a bridge for sale. One previous owner, slightly used and well maintained. Cash only.
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 112
From: Michigan
He asked about the ignition, coil is part of the ignition and the right one helps. Stop wasting my time explaining.
The vid was an example of some of the ways to free up power vs making more. LOL your tactic to misdirect by even bringing up NASCAR is poor taste. We are not in a court room this is not about who can argue best.
Now you resort to insults and I'm done. I always try to keep an open mind to achieve the max potential. I only respond to these threads to help some(the OP) since I've learned so much online and I given you enough chances to listen. I've given my examples and the details I'm willing to share.
Just remember your opinion is worth the same as mine online and I can say the same about anything you talk about.
The vid was an example of some of the ways to free up power vs making more. LOL your tactic to misdirect by even bringing up NASCAR is poor taste. We are not in a court room this is not about who can argue best.
Now you resort to insults and I'm done. I always try to keep an open mind to achieve the max potential. I only respond to these threads to help some(the OP) since I've learned so much online and I given you enough chances to listen. I've given my examples and the details I'm willing to share.
Just remember your opinion is worth the same as mine online and I can say the same about anything you talk about.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Start explaining. That is the reason why one posts "helpful" posts on a forum....not to be cryptic, and ellusive w/their incomplete posts.
Where did I say it was "poor taste"?? Please quote where I said that so that I can fix it, would you? What I DID say, was that it had nothing to do w/the OP's original question. As for the vid, like the OP or any of us here, are going to be using MASCAR engine practices in our street car engines.
Please quote where I insulted you, so that I can fix that, too. I don't believe that an insult was given anywhere in this thread.
Then start SHARING. Not parcelled out, bit's and pieces....explain, precisely how the OP should get his ~350 crank HP!
And I can post cryptic, leading, unhelpful thoughts, random videos of crap that don't relate to the thread at hand...but I'm not going to do it. I'm going to post specific solutions that actually work. I'm going to back that up w/real experience, and real objective data. 
Please quote where I insulted you, so that I can fix that, too. I don't believe that an insult was given anywhere in this thread.
Last edited by Tom400CFI; Dec 4, 2015 at 12:23 AM.
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
I had no idea we were shifting to NASCAR and what the potential of their engines are. I thought we were talking about the L98 in the Vette and specifically what real evidence you were bringing to the table instead of speculation and butt dyno feelings. I mean, if we talk about what my butt dyno thinks my car is making, I'd have to guess at 800 HP, possibly 950. And today, till midnight, I have a bridge for sale. One previous owner, slightly used and well maintained. Cash only.
I mean, if we talk about what my butt dyno thinks my car is making, I'd have to guess at 800 HP, possibly 950. And today, till midnight, I have a bridge for sale. One previous owner, slightly used and well maintained. Cash only.
Racer
Joined: Oct 2014
Posts: 323
Likes: 21
From: Apache Junction AZ
You could install a supercharger. It is basically bolt on and I've even seen one with oilless bearings so no messy oil lines. The cool thing about them (besides the sound) is that you can leave the engine pretty much stock but you have to reduce the boost to about 6 psi. It's an efficient way to push air through the rather restricted engine components. You might have to get larger injectors and a tune would be necessary. If I were going to go that way, I would probably pull the heads and have them freshened and add studs instead of bolts but that's just me. I have a L98 in my 91 convertible. I've scratched my head about how I would go about doing it. From what I have read, you can do more harm than good since the tuned manifold is critical. That's another reason why the blower works. It does not interfere with any of the OEM design. JMHO.
Good luck,
WEK.
Good luck,
WEK.
Team Owner
Joined: Jul 2004
Posts: 28,378
Likes: 3,261
From: Hartford WI
You could install a supercharger. It is basically bolt on and I've even seen one with oilless bearings so no messy oil lines. The cool thing about them (besides the sound) is that you can leave the engine pretty much stock but you have to reduce the boost to about 6 psi. It's an efficient way to push air through the rather restricted engine components. You might have to get larger injectors and a tune would be necessary. If I were going to go that way, I would probably pull the heads and have them freshened and add studs instead of bolts but that's just me. I have a L98 in my 91 convertible. I've scratched my head about how I would go about doing it. From what I have read, you can do more harm than good since the tuned manifold is critical. That's another reason why the blower works. It does not interfere with any of the OEM design. JMHO.
Good luck,
WEK.
Good luck,
WEK.
In what way do you mean the tuned manifold is critical? You can replace the entire thing with a Miniram, HSR, Superram, etc, etc.
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Back in the day I did the whole aftermarket coil and ignition upgrades. I later learned that the stock system does just fine for serious power increases.
86 coupe with supercharger did fine with the stock distributor and coil and my 383 in my 87 convertible has the stock coil and ignition and also produces power just fine.
The only use I see for aftermarket is at 6000 rpms and above.
86 coupe with supercharger did fine with the stock distributor and coil and my 383 in my 87 convertible has the stock coil and ignition and also produces power just fine.
The only use I see for aftermarket is at 6000 rpms and above.
Racer
Joined: Oct 2014
Posts: 323
Likes: 21
From: Apache Junction AZ
WEK.
Team Owner
Joined: Jul 2004
Posts: 28,378
Likes: 3,261
From: Hartford WI
If you want to fiddle with the intake, it should be one that is tried and true for this application. You could actually put an after market one on that would not be that impressive. You guys have mentioned a mini jet or something like that. Maybe that is one that is proven to work well on this engine. I don't have much experience with the sbc but I know a Holley Systemax makes a sbf run like a bat out of h*** from about 3000 to 6500 rpms. In one Hot Rod Mag project they did a bolt on dyno proven build and the Holley added 40 hp with no other changes on a 302. The built up engine (heads, cam, etc) with a SC would be a monster, I bet.
WEK.
WEK.