Gathering info on L92 416 build
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From: Rowing 6 speeds Maryland
Gathering info on L92 416 build Although I have searched and read up on all the L92 416 info, I don't see too many people have completed this build. I currently have 99 FRC with 346 with 234/238 @ .050 595/605 114 LSA and AFR 205 with 921 set up with all the headers and bolt ons. I'm putting down 450/400 RWHP/TQ through 4.10's.
I am looking to upgrade/stroker to over 400 CID and the way to go would be the L92/L76 set up. Does anyone have done this set up and running? Dyno results? I would like to know the cam options to attain somewhere in the 525/475 RWHP/TQ range. The dyno numbers are just numbers but that is a place to start.
I would most likely use SDPC for the complete long block but I would like to see some cam options/power out puts.
I welcome any and all inputs.
PS: This would be ported L92 heads with upgraded valves/springs of course.
I am looking to upgrade/stroker to over 400 CID and the way to go would be the L92/L76 set up. Does anyone have done this set up and running? Dyno results? I would like to know the cam options to attain somewhere in the 525/475 RWHP/TQ range. The dyno numbers are just numbers but that is a place to start.
I would most likely use SDPC for the complete long block but I would like to see some cam options/power out puts.
I welcome any and all inputs.
PS: This would be ported L92 heads with upgraded valves/springs of course.
Thread Starter
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iTrader: (11)
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From: Rowing 6 speeds Maryland
I think I found my heads and cam combo. This was originally posted by Jason 98 TA. lxer 242 duration intake & a 251 lsk exhaust. 111+2. 
PRC L92 CNC Head Vs. Stock L92 Head Results
Guys I spent several days working on different dyno combinations for the l92 headed engines. We recently dyno tested our 418cid l92 stroker with both the stock & Precision Race Components CNC ported L92 heads. Both cylinder heads were setup with the same chamber sizes & both heads used bone stock valves.
The 418 was built 11:1 with a lxer 242 duration intake & a 251 lsk exhaust. 111+2. I'll get the exact camshaft specs for you guys later on.
Base line power with this camshaft & stock heads was 604fwhp & 555lbft torque. The torque peak was at 4900rpm & the hp peak was at 6200rpm.
Without making any other changes we swapped over to the PRC CNC ported l92 heads & stock valves. The engine proceded to make several pulls into the 630ish range. The pull I printed went 570lb ft of torque @ 5100 & 631fwhp & 6400rpm.
At 3800 where the pulls started the stock & ported cylinder heads made within a couple of horses of each other. Past that point the couple of horse advantage quickly started to rise.
Shortly I'll post a dyno video of the l92 making dyno pulls. I wish I'd had decked the heads for some extra compression, but we just ran out of time.
The stock heads typically sell for about $850 a pair. Add double springs to that $850 & you quickly spend $1100 for a bone stock pair of heads. The fully cnc ported PRC cylinder heads will sell with stock valves for $1499! So basically for $400 you can gain a minimum of 27 additional horse & 15 lb ft of torque! Not bad for $400!!!
All & all I'm pretty pleased with the results. I wasn't sure how much power the motor would pickup when swapping a 350cfm head for one that already goes 308 or so. We hope to do some testing with stainless aftermarket valves in various sizes here shortly.
I'll keep you guys posted & I'll get some info together for all the different camshafts we tested in the next few days.
Guys I only got to make 1 pull because of harness issues, but it made 550rwhp & 510 lb ft with 11.4 a/f.
Jason
Guys I spent several days working on different dyno combinations for the l92 headed engines. We recently dyno tested our 418cid l92 stroker with both the stock & Precision Race Components CNC ported L92 heads. Both cylinder heads were setup with the same chamber sizes & both heads used bone stock valves.
The 418 was built 11:1 with a lxer 242 duration intake & a 251 lsk exhaust. 111+2. I'll get the exact camshaft specs for you guys later on.
Base line power with this camshaft & stock heads was 604fwhp & 555lbft torque. The torque peak was at 4900rpm & the hp peak was at 6200rpm.
Without making any other changes we swapped over to the PRC CNC ported l92 heads & stock valves. The engine proceded to make several pulls into the 630ish range. The pull I printed went 570lb ft of torque @ 5100 & 631fwhp & 6400rpm.
At 3800 where the pulls started the stock & ported cylinder heads made within a couple of horses of each other. Past that point the couple of horse advantage quickly started to rise.
Shortly I'll post a dyno video of the l92 making dyno pulls. I wish I'd had decked the heads for some extra compression, but we just ran out of time.
The stock heads typically sell for about $850 a pair. Add double springs to that $850 & you quickly spend $1100 for a bone stock pair of heads. The fully cnc ported PRC cylinder heads will sell with stock valves for $1499! So basically for $400 you can gain a minimum of 27 additional horse & 15 lb ft of torque! Not bad for $400!!!
All & all I'm pretty pleased with the results. I wasn't sure how much power the motor would pickup when swapping a 350cfm head for one that already goes 308 or so. We hope to do some testing with stainless aftermarket valves in various sizes here shortly.
I'll keep you guys posted & I'll get some info together for all the different camshafts we tested in the next few days.
Guys I only got to make 1 pull because of harness issues, but it made 550rwhp & 510 lb ft with 11.4 a/f.
Jason
