Need advice (383 LT1 Build) 500whp
06-12-2017, 07:55 PM
#43
06-13-2017, 08:42 AM
#45
TECH Regular
Keith screwed up my car so badly, it could barely idle correctly. I emailed him about it, and he insisted it was a problem with my car, and not his tune. I knew better and told him so. He then told me to take a hike - essentially robbing me of the $ I paid PCM4L to tune the car. Went with another tuner and it was a-ok. Amazing! I mean, if it was a problem with the car, the problem should have persisted through another tuner, right?
PCM For Less is currently run by a con artist and a thief. (Keith - go ahead and try to sue me over that. I've got everything in email form, sitting in my mailbox as proof. I'd welcome the opportunity to expose you as a crook to a wide audience.)
PCM For Less is currently run by a con artist and a thief. (Keith - go ahead and try to sue me over that. I've got everything in email form, sitting in my mailbox as proof. I'd welcome the opportunity to expose you as a crook to a wide audience.)
06-13-2017, 08:44 AM
#46
Keith screwed up my car so badly, it could barely idle correctly. I emailed him about it, and he insisted it was a problem with my car, and not his tune. I knew better and told him so. He then told me to take a hike - essentially robbing me of the $ I paid PCM4L to tune the car. Went with another tuner and it was a-ok. Amazing! I mean, if it was a problem with the car, the problem should have persisted through another tuner, right?
PCM For Less is currently run by a con artist and a thief. (Keith - go ahead and try to sue me over that. I've got everything in email form, sitting in my mailbox as proof. I'd welcome the opportunity to expose you as a crook to a wide audience.)
PCM For Less is currently run by a con artist and a thief. (Keith - go ahead and try to sue me over that. I've got everything in email form, sitting in my mailbox as proof. I'd welcome the opportunity to expose you as a crook to a wide audience.)
06-13-2017, 10:38 AM
#47
TECH Regular
I've been messing with LT1s for 18 years. I can count the number of street-oriented LT1 cars I know of that have made 490+rwhp SAE with a hydraulic roller cam on one hand. All of them have manual transmissions. Also, all of them have been built by owners, shops, and head porters that I would consider to be the foremost experts in the LT1 world with 15+ years of intensive experience with the platform.
Oh, and one other thing. For every LT1 street-oriented HR build that acutally makes 500rwhp SAE on a dynojet, there are several others that are spec'd and built by people just as good and just as experienced, that make in the 470 to 490 range. That is still a hell of an achievement with this platform, but there are several dozen that have done it. To do this, it generally takes a top-notch rotating assembly, aftermarket 210+cc castings with a top notch (AI or LE) port job, EXCELLENT tuning, and everything perfectly up to snuff with the induction and exhaust.
Oh yea, and for every LT1 stroker making 470+ like mentioned above, there are a dozen or more LT1 strokers built by the rest of us with a set of merely "very good" ported factory castings (AI 190s/200s or LE2s/3s) making somewhere between 420 and 450rwhp. When most people ask about a typical budget and street friendly LT1 stroker build, this is what I typically would tell them to expect if they know what they're doing and everything is up to par.
Your uncle set his goal pretty high for being someone who seems to know almost nothing about this platform. The builder seems not to know much either, as what he has spec'd will likely end up making 375 through that 4L60 on a good day. If he does indeed go with that particular builder, the advice I would give him would be as follows:
-make sure your builder achieves a SCR of 11.5 or better, through quench. You can do this with pump gas on a LT and it won't hurt anything.
-a quality set of pistons that are as light, or lighter than stock is what you want. The Mahle Powerpacks are good.
-unless your guy has a long track record and lots of experience building high hp LT motors, less is more on the head work. It's easy to eff up a set of LT heads if someone who doesn't know what they're doing tries to reshape the ports.
-pick a cam with less than 234 or so degrees of intake duration and a tight (108-110) lsa. It'll be a lot more fun and street friendly and still make good power.
-Put a set of good rod bolts in.
If you follow those few guidelines, you'll end up with something that at least makes enough midrange punch to be fun to drive on the street and may end up cracking the 400rwhp barrier. But with the rest of the build the way it is, I wouldn't expect much more than that.
Oh, and one other thing. For every LT1 street-oriented HR build that acutally makes 500rwhp SAE on a dynojet, there are several others that are spec'd and built by people just as good and just as experienced, that make in the 470 to 490 range. That is still a hell of an achievement with this platform, but there are several dozen that have done it. To do this, it generally takes a top-notch rotating assembly, aftermarket 210+cc castings with a top notch (AI or LE) port job, EXCELLENT tuning, and everything perfectly up to snuff with the induction and exhaust.
Oh yea, and for every LT1 stroker making 470+ like mentioned above, there are a dozen or more LT1 strokers built by the rest of us with a set of merely "very good" ported factory castings (AI 190s/200s or LE2s/3s) making somewhere between 420 and 450rwhp. When most people ask about a typical budget and street friendly LT1 stroker build, this is what I typically would tell them to expect if they know what they're doing and everything is up to par.
Your uncle set his goal pretty high for being someone who seems to know almost nothing about this platform. The builder seems not to know much either, as what he has spec'd will likely end up making 375 through that 4L60 on a good day. If he does indeed go with that particular builder, the advice I would give him would be as follows:
-make sure your builder achieves a SCR of 11.5 or better, through quench. You can do this with pump gas on a LT and it won't hurt anything.
-a quality set of pistons that are as light, or lighter than stock is what you want. The Mahle Powerpacks are good.
-unless your guy has a long track record and lots of experience building high hp LT motors, less is more on the head work. It's easy to eff up a set of LT heads if someone who doesn't know what they're doing tries to reshape the ports.
-pick a cam with less than 234 or so degrees of intake duration and a tight (108-110) lsa. It'll be a lot more fun and street friendly and still make good power.
-Put a set of good rod bolts in.
If you follow those few guidelines, you'll end up with something that at least makes enough midrange punch to be fun to drive on the street and may end up cracking the 400rwhp barrier. But with the rest of the build the way it is, I wouldn't expect much more than that.
Last edited by HellTeeOne; 06-13-2017 at 10:53 AM.
06-13-2017, 12:31 PM
#48
HellTeeOne, do you think 400rwhp is possible with LE1 heads flowing 260cfm with 2.02/1.60 valves on a m6 383?
I'm wanting at least 450fwhp and tons of torque out of my build. Peak torque around 4k, peak hp in the 5500-5800rpm range.
Im thinking peak torque close to 500lbs would be more important to me over having peak hp numbers over 6k.
I'm wanting at least 450fwhp and tons of torque out of my build. Peak torque around 4k, peak hp in the 5500-5800rpm range.
Im thinking peak torque close to 500lbs would be more important to me over having peak hp numbers over 6k.
06-13-2017, 01:00 PM
#50
06-13-2017, 02:49 PM
#52
http://www.enginelabs.com/news/video-383ci-stroker-lt1-makes-a-strong-case-for-gen-ii-engines/ This is my motor. These heads are for sale for $1000.00
06-13-2017, 06:48 PM
#54
It was on a carburator Dyno. That's usually going to make more power than the LT1 intake. http://www.jegs.com/p/Dart/Dart-LT1-LT4-Pro-1-Aluminum-Cylinder-Heads/932783/10002/-1 . These are the heads. It should have all the information on them here.
06-14-2017, 02:09 PM
#55
TECH Regular
HellTeeOne, do you think 400rwhp is possible with LE1 heads flowing 260cfm with 2.02/1.60 valves on a m6 383?
I'm wanting at least 450fwhp and tons of torque out of my build. Peak torque around 4k, peak hp in the 5500-5800rpm range.
Im thinking peak torque close to 500lbs would be more important to me over having peak hp numbers over 6k.
I'm wanting at least 450fwhp and tons of torque out of my build. Peak torque around 4k, peak hp in the 5500-5800rpm range.
Im thinking peak torque close to 500lbs would be more important to me over having peak hp numbers over 6k.
06-14-2017, 07:42 PM
#56
My 215/224 cam on my stock headed lt1 gave me my stock like torque and hard hitting midrange but only so so power after 5k......so yeah i will heed your advice and cam the 383 for at least a 6k peak. I would kind of like to stick with my gm "crane" self alligning roller rockers for the 383. I don't feel i need to switch over to NSA if im only reving to 6000- 6200 max. Im guessing those 2.00 1.56 valves would be enough then on le1's or le2's.
Keeping my meziere ewp.
Maybe bore out the stock TB to 52mm.
Keeping my mac mids on because they fit perfect. Catless y pipe. Figure its worth having lloyd port the intake to the heads for $200 too.
Keeping my meziere ewp.
Maybe bore out the stock TB to 52mm.
Keeping my mac mids on because they fit perfect. Catless y pipe. Figure its worth having lloyd port the intake to the heads for $200 too.
06-14-2017, 10:47 PM
#57
cams that make the bigger HP do so at high RPM. Good for racing
Street driving low-mid range TQ is what you want.
The 383 just on increased CI will get you more TQ over a identical 350.
Talk to Lloyd on what your use intent and HP/TQ goals are. There are several other factors that will effect how much cam you should go with
On your SA RR.....above 5500 RPM...if the valve springs are not PERFECT you stand a chance of popping one off the valve tip. So if going for the higher HP, thus higher RPM use, I would strongly encourage NSA and guide plates. At that point go 7/16" RR studs.
Yes on 52mm. Get stock TB bored. IMHO way more plug & play vs aftermarket TB.
You "may" (read most do) need 30 LB injectors to support the H/C
...yes it is a domino effect
Street driving low-mid range TQ is what you want.
The 383 just on increased CI will get you more TQ over a identical 350.
Talk to Lloyd on what your use intent and HP/TQ goals are. There are several other factors that will effect how much cam you should go with
On your SA RR.....above 5500 RPM...if the valve springs are not PERFECT you stand a chance of popping one off the valve tip. So if going for the higher HP, thus higher RPM use, I would strongly encourage NSA and guide plates. At that point go 7/16" RR studs.
Yes on 52mm. Get stock TB bored. IMHO way more plug & play vs aftermarket TB.
You "may" (read most do) need 30 LB injectors to support the H/C
...yes it is a domino effect
06-15-2017, 09:45 AM
#58
Build a sloppy *** 383, keep it cheap but forged. Then buy turbo kit from below
http://lt1boost.net/cast_manifold_kit
Then add boost to reach this magical 500rwhp number that you want.
Simple.
http://lt1boost.net/cast_manifold_kit
Then add boost to reach this magical 500rwhp number that you want.
Simple.
06-15-2017, 10:05 AM
#59
TECH Regular
My 215/224 cam on my stock headed lt1 gave me my stock like torque and hard hitting midrange but only so so power after 5k......so yeah i will heed your advice and cam the 383 for at least a 6k peak. I would kind of like to stick with my gm "crane" self alligning roller rockers for the 383. I don't feel i need to switch over to NSA if im only reving to 6000- 6200 max. Im guessing those 2.00 1.56 valves would be enough then on le1's or le2's.
Keeping my meziere ewp.
Maybe bore out the stock TB to 52mm.
Keeping my mac mids on because they fit perfect. Catless y pipe. Figure its worth having lloyd port the intake to the heads for $200 too.
Keeping my meziere ewp.
Maybe bore out the stock TB to 52mm.
Keeping my mac mids on because they fit perfect. Catless y pipe. Figure its worth having lloyd port the intake to the heads for $200 too.
Unless you blatantly over-cam a LT motor (say, more than 230 degrees of intake duration without a corresponding significant bump in SCR and better flowing heads), you're not going to lose any midrange. My stock bottom end setup actually makes equivalent midrange and a better overall curve than many over-cammed strokers.
Also, running a lsa of 112 or tighter helps. There's really no compelling reason to run a lsa any wider than that unless you're a max effort boost or nitrous oriented setup, or trying to pass emissions in some commie jurisdiction.
06-15-2017, 01:19 PM
#60
Village Troll 
iTrader: (2)
Build a sloppy *** 383, keep it cheap but forged. Then buy turbo kit from below
http://lt1boost.net/cast_manifold_kit
Then add boost to reach this magical 500rwhp number that you want.
Simple.
http://lt1boost.net/cast_manifold_kit
Then add boost to reach this magical 500rwhp number that you want.
Simple.