LS1 Lid conversion Dyno
#1
11 Second Club
Thread Starter
iTrader: (4)
Join Date: Nov 2001
Location: Woodinville, WA
Posts: 787
Likes: 0
Received 0 Likes
on
0 Posts
LS1 Lid conversion Dyno
Dyno of LT1 conversion Lid and 85mm maf on my 236/245 Hyd roller cammed 401, thru 12 bolt, and locked auto. New numbers were with under drive pulley removed (went to SFI dampner), and heat range 9 plugs (for 200 shot) vs. heat range 4. New dyno numbers were way lean and I picked up 5tq and 6hp more than this graph thru the whole pull after tuning. 420.65TQ and 460.33HP SAE corrected now. My old numbers were 424.01TQ and 448.15HP SAE. So, I picked up 12 rwhp with this MOD, even after taking away a little with the pulley and plugs (I'm assuming that's were some of my torque went). Numbers Uncorrected were 439.54TQ and 481.00HP. Using this graph to show how my old combo was starving for air upstairs above 6K rpm...Nice gain with a upper rpm that looks more like a mechanical roller than my little HYD (for a 401 cube engine)...HP peak is now at 6425rpms instead of 6275rpms. Good Mod for me but I'm not sure less agressive combos would be worth it...time will tell
[IMG]URL=http://imageshack.us][/URL][/IMG]
[IMG]URL=http://imageshack.us][/URL][/IMG]
#3
11 Second Club
Thread Starter
iTrader: (4)
Join Date: Nov 2001
Location: Woodinville, WA
Posts: 787
Likes: 0
Received 0 Likes
on
0 Posts
Yes....Was my old 396 combo, now this year with 60 over pistons (note to people have your blocks sonic checked if going this big), I'v been running this stroker sense 1997 with ZERO problems and hundreds of drag passes over the years + a **** ton of dyno runs
I'm more impressed with the upper rpm band...Not bad for an actual "Daily Driver." 12 1/2inches of vacuum at idle, air and everything else is still on the car + roll bar....20MPG on the freeway. I'm still not sure if this power gain was from the Air Intake Mod or the 85mm MAF. Someone needs to dyno a before and after MOD (with stock MAF) a give us the answer......
I'm more impressed with the upper rpm band...Not bad for an actual "Daily Driver." 12 1/2inches of vacuum at idle, air and everything else is still on the car + roll bar....20MPG on the freeway. I'm still not sure if this power gain was from the Air Intake Mod or the 85mm MAF. Someone needs to dyno a before and after MOD (with stock MAF) a give us the answer......
#4
Its nice to see that the LS1 lid made more power, but what was the deal with the old power curve. If the motor was not getting enough air, why did the power bump back up at the end. Could something else have caused the drop, or do you think it was just the intake?
Trending Topics
#8
11 Second Club
Thread Starter
iTrader: (4)
Join Date: Nov 2001
Location: Woodinville, WA
Posts: 787
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by foggedz
Its nice to see that the LS1 lid made more power, but what was the deal with the old power curve. If the motor was not getting enough air, why did the power bump back up at the end. Could something else have caused the drop, or do you think it was just the intake?
All my older dynos with this same cam minus the air intake mods had this problem. You could actually feel the power start to go away (not bad though). I been tuning ever sense Beta LT1 edit days and could not get that straight with any timing or fuel adjustment (In fact that is my best dyno upstairs wise). Now it's weird that the Air tract and Maf would fill that area in but all 4 new dynos were all good up in that rpm....This may be a 401 cube problem (air pulsing in the intake manifold or maybe reversion/cam overlap in a certain area, anybodies quess on that one). Maybe Ed Wright or some of the other guys with weird dynos pulls from LT1's might have a better clue.
Oh, yeah...Forgot to mention that I had a GM 847 cam in there at one time and it did the same thing...and made 4-5 rear wheel less. Peaked a little earlier and had a little more drop off in the 6500-7000rpm area.."Good cam imo for an off the shelf grind".....
Yep, the dyno had a problem with lead connector, plus I would break loose the tires during some part of most runs....
Last edited by jimbob; 02-05-2007 at 12:36 PM.
#11
11 Second Club
iTrader: (46)
Join Date: Oct 2002
Location: tulsa ok
Posts: 1,617
Likes: 0
Received 0 Likes
on
0 Posts
me personally i would swap that back to the LT1 stuff and redyno
you seemed to lose under 5500 with the new stuff
i would much rather have that back then make that all mighty peak number UNLESS you always have the motor runnin at 6500
you seemed to lose under 5500 with the new stuff
i would much rather have that back then make that all mighty peak number UNLESS you always have the motor runnin at 6500
#13
11 Second Club
Thread Starter
iTrader: (4)
Join Date: Nov 2001
Location: Woodinville, WA
Posts: 787
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Z284thgen
me personally i would swap that back to the LT1 stuff and redyno
you seemed to lose under 5500 with the new stuff
i would much rather have that back then make that all mighty peak number UNLESS you always have the motor runnin at 6500
you seemed to lose under 5500 with the new stuff
i would much rather have that back then make that all mighty peak number UNLESS you always have the motor runnin at 6500
Valve float, here's the story...I use to think that, but could never explain it after using parts that I know work well with certain cam grinds I have chosen (not tooting my horn..but have had 12 years of experience with this combo). Anyway, tried several cam swaps and the upper rpm area always took a dive. I finally tried a very easy on the valves, 847 cam that never had a problem before in the upper rpms on my car (the last cam in my old pre manifold mod .060 over bore). Did the exact same thing, only at a little lower rpm....For reference I run 175 lbs (doesn't colapse the old version comp R's) of seat pressure and 420lbs at .6 lift with titanium retainers, .080 thick wall push rods and Pro Magnum Roller Rockers.....I was still going to try the bee hives springs set up from Bret Bauer, but did this mod first. Actually, I always thought it was the curtain area of the intake valve holding me back (not enough lift or duration), due to loosing a little more rpm with a mild 847 cam (less lift). But did this mod, retuned and bam. Noticed right away it was better in the upper rpm's on the street (This was before changing plugs and pulley). So, I never expected this outcome, as I was only looking to see if I could gain some peak area power. I do have dynos of valve float on my engine from late 1990's when I tried Extreem cams from comp though... not pretty
The whole thing is weird and only expected 4-6 rear wheel horse power from the MAF only (ED Wright gave me some numbers from his way old combo in this horse power range). For right now I'll just go with it and let some of the other math and physics gurus figure it out....
#15
11 Second Club
Thread Starter
iTrader: (4)
Join Date: Nov 2001
Location: Woodinville, WA
Posts: 787
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by streetwarrior96
nice numbers man.. any pics of that LS1 intake
speed_demon24
Yep, that is what I would have believed if i had not seen it myself. I'm a poster that WILL tell you everthing that happends (no holds bar) good or bad. I think TWOFAST4LV and I have been more then forth coming on what we accomplish or don't.....But thanks for the props::: "Something else was causing that problem, and it was obviously fixed when you re-dyno'd it." After reading my post I figured it was "Not" so, obvious, wish it had been......I will still monitor in case I have to eat those words.....
streetwarrior96
I see you already have something similar on yours.....I hope to justify the time and expense this spring time....Could not make a good run with it last race of the season...Hopefully 11.1-11.2 will be there. Might need some more gearing and stall to take advantage of the upper rpm area now...
Last edited by jimbob; 02-05-2007 at 07:50 PM.
#17
11 Second Club
Thread Starter
iTrader: (4)
Join Date: Nov 2001
Location: Woodinville, WA
Posts: 787
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by the_merv
Mine is similar to that.
I fixed that problem with the Radiator hose near the ABS there. I put in a little extra piece of metal to make sure that hose wouldn't get rubbed and get a hole in it. It's not in this picture.
I fixed that problem with the Radiator hose near the ABS there. I put in a little extra piece of metal to make sure that hose wouldn't get rubbed and get a hole in it. It's not in this picture.
Good job on that Air intake by the way...
#19
TECH Apprentice
iTrader: (5)
Join Date: May 2006
Location: jackson ohio
Posts: 328
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by jimbob
Cool thanks ....I was thinking of something similar but have not got around to it....Need to fix that just in case....don't want to get bit in the *** later....or worse at the drags....
Good job on that Air intake by the way...
Good job on that Air intake by the way...