Least restrictive LT1 induction?
12sec.. it is not the easiest conversion unless you are OK with modifying stuff to make it fit. Fitting it is not so much the issue, as making it fit AND look clean. I have a Glasstek 4" cowl hood, and I know others have used this hood with a lid. Some other cowl hoods have clearance.. some do not.The hood needs a little notching even still. The LS1 lid base needs to be shaved down so it sits lower on the rad support. It gets a lot harder if you don't have the hood, and want to keep your stock rad and AC.
I have the stock radiator and a/c. I had to shave the lower air box/ radiator support do that it sat flush to the core support. It took about 10 minutes with a dremel and fitting. The main kicker is I run a VFN Sunoco wide bolt on hood. Mine was special made the same as BOLO's. It's made to clear the lid with no cutting to the hood. They don't charge any extra to have the hood made this way so if you want one you just need to ask. It was definitely worth the wait on the hood to make sure I didn't have to cut my core support, and it makes for a cleaner, more factory looking install.
Far as cranking compression, a stock LT1 can crank 200psi a built one over 12:1 compression might crank 240psi or more cam plays a meaningful part. If you want to worry about it ask Lloyd for a ballpark number as he would know the complete specs on the cam not just the simple specs you posted.
My old 190cc setup cranked like 227psi and was 11.2 compression. Current setup cranks even higher.
Really though I think the CAI is the culprit here, if the HP had gone wonky instead of flatline I would look at valve float. If it had just been soft from the start I would be looking at compression and some other things.
My old 190cc setup cranked like 227psi and was 11.2 compression. Current setup cranks even higher.
Really though I think the CAI is the culprit here, if the HP had gone wonky instead of flatline I would look at valve float. If it had just been soft from the start I would be looking at compression and some other things.
Oh it also struck me that "make power to 7400rpm" could begin to plateau by say 6700 peak by 7000 and just not begin to fall off hard by 7400. My experience is with hydraulic setup but I can tell you some of the fastest heads/cam setups peak about 64-6500 but still making great power at 7-7100rpm when the pcm stops working right.
Thanks for the responses about the LS1 lid. If I can get ahold of a 96-97 WS6 air box, that should be much more simple to fit shouldn't it? Assuming a hood to properly clear it, of course.
Banned
Joined: Jan 2013
Posts: 588
Likes: 0
From: Las Vegas
Cranking/compression pressure not only tells u condition of cyl(s) but if your cam is spec'd correctly for your dynamic c.r. keeping u out of detonation. The reverse cooled LT1 may be more tolerant with this and the old sbc thumb rules may not be as accurate for the LT1. But on the other hand if your receiving the beginning of detonation the PCM will retard timing allowing the eng to run but u would be losing power. Without retard for knock eng life would be shortened.
Compression test/press for your build would be good for u to know rather than rely on hearsay or someones else's guess. It only takes 'bout and hour to do.
cardo
Compression test/press for your build would be good for u to know rather than rely on hearsay or someones else's guess. It only takes 'bout and hour to do.
cardo
Far as cranking compression, a stock LT1 can crank 200psi a built one over 12:1 compression might crank 240psi or more cam plays a meaningful part. If you want to worry about it ask Lloyd for a ballpark number as he would know the complete specs on the cam not just the simple specs you posted.
My old 190cc setup cranked like 227psi and was 11.2 compression. Current setup cranks even higher.
Really though I think the CAI is the culprit here, if the HP had gone wonky instead of flatline I would look at valve float. If it had just been soft from the start I would be looking at compression and some other things.
My old 190cc setup cranked like 227psi and was 11.2 compression. Current setup cranks even higher.
Really though I think the CAI is the culprit here, if the HP had gone wonky instead of flatline I would look at valve float. If it had just been soft from the start I would be looking at compression and some other things.
Last edited by 12sec97Z28; Feb 16, 2014 at 12:11 PM.
Cranking/compression pressure not only tells u condition of cyl(s) but if your cam is spec'd correctly for your dynamic c.r. keeping u out of detonation. The reverse cooled LT1 may be more tolerant with this and the old sbc thumb rules may not be as accurate for the LT1. But on the other hand if your receiving the beginning of detonation the PCM will retard timing allowing the eng to run but u would be losing power. Without retard for knock eng life would be shortened.
Compression test/press for your build would be good for u to know rather than rely on hearsay or someones else's guess. It only takes 'bout and hour to do.
cardo
Compression test/press for your build would be good for u to know rather than rely on hearsay or someones else's guess. It only takes 'bout and hour to do.
cardo
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Banned
Joined: Jan 2013
Posts: 588
Likes: 0
From: Las Vegas
I believe that would be less than 1 degree from what was previously mapped. No one really knows what your timing map should be until u test the engine. Every engine will have its own timing (advance) "map". But how much timing it could have with your pump gas octane without excessive detonation/pre-ignition is limited by your dynamic compression ratio and reflected in your cranking pressure.
cardo
cardo
Past seeing the difference between air filter vs no air filter on the dyno, you may need something like a sheet metal intake to really open things up.
I'm not a NA solid roller, but my cam is a 244/254 .574 114 LSA and the blower really needed a lot of air to see some gains. I ended up doing a custom sheet metal intake, and was very happy with the results.
I'm guessing you wanted to stay away from the sheet metal intake because of the cost. If you know anyone who fabricates, it may not be as bad as you think. I would never drop the coin that some of the ones go for online $1k+. I'm not saying mine was cheap, but it wasn't that bad either.
I'm not a NA solid roller, but my cam is a 244/254 .574 114 LSA and the blower really needed a lot of air to see some gains. I ended up doing a custom sheet metal intake, and was very happy with the results.
I'm guessing you wanted to stay away from the sheet metal intake because of the cost. If you know anyone who fabricates, it may not be as bad as you think. I would never drop the coin that some of the ones go for online $1k+. I'm not saying mine was cheap, but it wasn't that bad either.
Last edited by CALL911; Feb 17, 2014 at 02:00 PM.
My 2 cents on this.
I had a Moroso (or Honker) CAI and a K&N CAI and I wanted to determine which one is better flowing. I tried both and monitored the pressure drop at the MAP sensor using datamaster and determined that the K&N has about 2KPA lesser drop compared to the Moroso at WOT. I would say that the much larger filter on the K&N CAI accounted for this. So IMO, the K&N flowed better. Is it worth ditching a Moroso and getting a K&N, no.
I then did a similar test with out a CAI installed without a CAI installed to see if the MAF had any restriction. So testing with the MAF on and then off, no change. The MAF poses no obvious restriction.
Same test with the elbow with no MAF or CAI installed. Big difference in pressure drop with the elbow pulled. SAo IMO, the 90 degree elbow poses a very significant restriction in the LT1 induction while the other components, not so much. I would guess that the flowing air in the elbow just gets "slowed" as it passes through hence the reason the LS1 straight should induction design works so much better.
I have an old thread somewhere speaking to these findings in much greater detail if your interested.
I had a Moroso (or Honker) CAI and a K&N CAI and I wanted to determine which one is better flowing. I tried both and monitored the pressure drop at the MAP sensor using datamaster and determined that the K&N has about 2KPA lesser drop compared to the Moroso at WOT. I would say that the much larger filter on the K&N CAI accounted for this. So IMO, the K&N flowed better. Is it worth ditching a Moroso and getting a K&N, no.
I then did a similar test with out a CAI installed without a CAI installed to see if the MAF had any restriction. So testing with the MAF on and then off, no change. The MAF poses no obvious restriction.
Same test with the elbow with no MAF or CAI installed. Big difference in pressure drop with the elbow pulled. SAo IMO, the 90 degree elbow poses a very significant restriction in the LT1 induction while the other components, not so much. I would guess that the flowing air in the elbow just gets "slowed" as it passes through hence the reason the LS1 straight should induction design works so much better.
I have an old thread somewhere speaking to these findings in much greater detail if your interested.
TECH Addict
Joined: Feb 2012
Posts: 2,103
Likes: 21
I bought my car with a K&N intake. Not only did I not like the idea of the 90* bend before the TB, but I didn't like how the intake tube has a funky shape.
Here was my solution:
I have no data to say whether the new intake is an improvement or not. I just dl DataMaster and need to pick up a cable to be able to data log. I also have not gone WOT just in case it does flow that much better, I do not want to create a lean condition. I have plans to dyno tune the car soon though. That is a 4" to 3.5" coupler from TB to MAF, then the MAF, then 3.5" to 3.5" coupler to 3.5" exhaust pipe. MINIMAL hood bracing notching was required and a little flattening of at the top radius of the pipe...This fits under a stock 95 hood as well. It's the first prototype so it's not the prettiest but it seems to function lol.
Here was my solution:
I have no data to say whether the new intake is an improvement or not. I just dl DataMaster and need to pick up a cable to be able to data log. I also have not gone WOT just in case it does flow that much better, I do not want to create a lean condition. I have plans to dyno tune the car soon though. That is a 4" to 3.5" coupler from TB to MAF, then the MAF, then 3.5" to 3.5" coupler to 3.5" exhaust pipe. MINIMAL hood bracing notching was required and a little flattening of at the top radius of the pipe...This fits under a stock 95 hood as well. It's the first prototype so it's not the prettiest but it seems to function lol.
You said its a custom sheet metal intake, when in fact you have a cast super vic intake. You have a sheet metal elbow, not intake. Just saying.
Pointless semantics is posting a blower motor to offer advice to a NA motor question.
Banned
Joined: Jan 2013
Posts: 588
Likes: 0
From: Las Vegas
Yes, there are several lurkers here that have no helpful intentions.
I just consider them as parasitic drag to enthusiasm for high performance. Debating with them is wasted effort. But I do enjoy telling them that.
cardo
