The valve seals? Hogwash! That's not where it's coming from. It's a little blowby getting past the rings. It's normal. You're wasting your time with seals.
What hp and torque am I making?
- Thread starter dustyaman
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Didn't engine masters do it once with a lot of other cams?
They have numerous times but it is always at Westech on their dyno.
275-290hp 325tq
The sums of the parts is less than a factory 340.
The sums of the parts is less than a factory 340.
Yeah the heads kill the hp. I'm probably missing 50 hp because of them but it is on the wish list to get some trick flows.
I'll throw my slightly informed WAG out there- 321 HP 378 LB FT
I ain't sure I go along with that. Think of these differences. First, he's got 20 more cubes. Next, he's got a WAY more modern camshaft grind. 110 LSA VS I forget....either 115 or 116, so there's some cylinder pressure right there to help make up for the lower static compression. Plus, he's runnin headers. I think with a good hot ignition curve with initial 16-20 and total limited to 34 or so and he's all over @crackedback's estimate. Either way, it's gonna be a dang hoot to drive. Old school build and I love it.
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What's a WAG?
I left out his better than the 340 intake, too.
Wild arse guess
Yeah, those intakes make awesome torque down low!
Yes and it came in about where I said for my numbers. I might be a little high, Maybe in the 325-335 area and 375tq. No chance that makes less than 300hp with the cam it has unless something is VERY wrong. Same cam, 1.88 J's, LD340, 750DP Dougs, 9.7:1 about 350/395 IIRC. This one may be lacking a little from heads and compression
Maybe compression and 1.88 heads are lacking. The cam is MUCH larger than a factory 340. .477 lift on intake vs the 340 .429.... That will make a BIG difference.
I'll stick to my real world guesstimate .
It should be a fun car either way
It should be a fun car either way
Exactly. It's not like it's an over bloated overweight Camaro. lol
Sounds exactly right. Dulcich did a supposedly everything stock 340 build with the 268xe and X heads with a 3 angle valve job and claimed 400 hp. That is what makes me think the Westech dyno is a little happy. Must have had some magic dyno dust sprinkled around that day.
OP's build will be lots of fun on little coin- what hot rodding is about in my mind. Need to get those stock 360 springs swapped out though to let that combo rpm like it can.
HP numbers are highly subjective, too. It all depends on what corrections are used and so forth. Are they claiming net or gross? Just too many variables to really nail it down. I like to say "it'll be a fun ride" and leave it there, really, because it will be.
Some old school combos listed here for reference sake. First 3 builds could be improved on with a more modern cam grind and air gap intake.
Dyno proven 360 packages
Package one:
Rebuilt 360 with factory crank and rods. Cast 9 to 1 compression flat top pistons. Heads are "308" swirl port heads from 1988-91, rebuilt with competition valve job and a slight mill to true up the surface. Camshaft is MP P4452759 .430"/.450" lift, 260/268 duration, 110 lsa, installed at 108 intake centerline. MP M1 dual plane intake P4529116, 750 Holley #3310 carb, 1 5/8" small primary tube headers.
300 h.p. @ 4750 rpm
350 lbs. torque @ 4,000 rpm
Package two:
360 rebuild with stock crank, rods and windage tray. 9 to 1 cast flat top pistons. Heads are "J" castings with 2.02" intake and 1.60" exhaust, competition valve job, lightly bowl prepped. Intake is the Edelbrock RPM, carb is the Carter Competition 750. Hooker 1 3/4" headers. Timing set at a total of 32 degrees. Cam is an Edelbrock RPM with .488" lift and 308 duration installed at a 107 intake centerline.
370 h.p. @ 5,750 rpm
360 lbs. of torque @ 4,250 rpm
Package three:
360 rebuild with stock crank, rods and windage tray. Factory iron 360 heads from a 1979 motor opened to 2.02" intake valves with a competition valve job. Bowls lightly blended and runners lightly cleaned up. TRW flat top cast pistons rated at 10. to 1 compression. Comp Cams Magnum hydralic 280 cam. This cam has a .480" lift and 280 degrees advertised duration. Intake is an Edelbrock Torker II. Topped with a Carter TQ with .137 rear jets.
401 h.p. @ 5,400 rpm
420 lbs. of torque @ 4,700 rpm
Package four:
360 rebuilt to 9.9:1 compression, Eddelbrock heads, Edelbrock RPM Airgap intake, 750 Eddelbrock carb, Hughes cam HE2430 with 224/230 degrees @ .050", .504"/.515" lift, 1 5/8" headers.
397 h.p. @ 5,500 rpm
436 lbs. of torque @ 3,800 rpm
Package five:
This package is a little more pricey but it is a bolt on package with all parts right out of the box using the Edelbrock RPM parts/package. 360 rebuilt with stock crank and rods, block bored .030" over, 9.5 to 1 flat top pistons. Edelbrock RPM heads, RPM intake, Performer 750 carb and RPM camshaft with .488" lift and 308 advertised duration, installed at 110 intake centerline. Timing was set at 34 degrees total.
399 h.p. @ 5,500 rpm
438 lbs. of torque @ 4,250
Package five-B:
The above motor was tried with a modified Holley carb flowing over 800 cfm and having .076" front jets and .080" rear jets.
430 h.p. @ 5,750 rpm
469 lbs. of torque @ 4,000 rpm
Package six:
Rebuilt 360, bored .030" over with Hypereutectic pistons, bowl ported smog type 360 heads with 2.02" intake valves and competition valve job. Edelbrock Torker II intake, Carter 750 AVS, Comp Cams Magnum roller rockers, Comp Cams custom ground solid lift tight lash cam with .542"/.549" gross lift, 272/276 advertised duration, 243/247 duration at .050" with 108 lsa and a 108 intake centerline. Headers with small 1 5/8" primery tubes.
430 h.p. @ 6,000 rpm
412 lbs. of torque @ 4,900 rpm
Package seven:
360 rebuilt with factory crank and rods, KB191 high compression pistons with 12:1 compression, 2.02" "J" heads ported to flow 260 cfm,Holley 3310 750 cfm, Victor intake, 1 3/4" primary tube headers, Engle Cams solid tappet KV-2 cam with .560 gross lift, 275 advertised duration, 245 @ .050", 110 lobe seperation angle and 106 intake centerline.
450 h.p. @ 6,200 rpm
425 lbs. of torque @ 4,250 rpm
Package eight:
360 rebuilt with 9.5 to 1 cast pistons, original crank, rods and windage tray. 202 heads with competition valve job and ported to flow 260 cfm. Edelbrock RPM intake, Holley 750 rejetted, Large tube headers and Mopar Performance P4120231 cam with .484" lift, 284 duration, 108 lsa, installed at 106 intake centerline.
460 h.p. @6000 rpm
486 lbs. of torque @ 4,250 rpm
Package nine:
360 rebuilt with 10:1 compression flat top cast pistons, original crank turned .010"/.010", rebuilt factory rods. Factory windage tray installed. 2.02" heads with competition valve job and ported to flow 260 cfm. Edelbrock RPM intake, port/gasket matched. Holley H.P. 750 (.076" front, .080" rear jets). Large 1 3/4" primary tube headers. Comp Cams 305AH-8 camshaft with .525"/.540" lift and 305/312 degree advertised duration, 253/260 degrees @ .050", 110 lsa, installed at 108 intake centerline. This motor is a brute for a street car and would only be considered a weekend blaster.
495 h.p. @ 6,000 rpm
500 lbs. of torque @ 4,500 rpm
Dyno proven 360 packages
Package one:
Rebuilt 360 with factory crank and rods. Cast 9 to 1 compression flat top pistons. Heads are "308" swirl port heads from 1988-91, rebuilt with competition valve job and a slight mill to true up the surface. Camshaft is MP P4452759 .430"/.450" lift, 260/268 duration, 110 lsa, installed at 108 intake centerline. MP M1 dual plane intake P4529116, 750 Holley #3310 carb, 1 5/8" small primary tube headers.
300 h.p. @ 4750 rpm
350 lbs. torque @ 4,000 rpm
Package two:
360 rebuild with stock crank, rods and windage tray. 9 to 1 cast flat top pistons. Heads are "J" castings with 2.02" intake and 1.60" exhaust, competition valve job, lightly bowl prepped. Intake is the Edelbrock RPM, carb is the Carter Competition 750. Hooker 1 3/4" headers. Timing set at a total of 32 degrees. Cam is an Edelbrock RPM with .488" lift and 308 duration installed at a 107 intake centerline.
370 h.p. @ 5,750 rpm
360 lbs. of torque @ 4,250 rpm
Package three:
360 rebuild with stock crank, rods and windage tray. Factory iron 360 heads from a 1979 motor opened to 2.02" intake valves with a competition valve job. Bowls lightly blended and runners lightly cleaned up. TRW flat top cast pistons rated at 10. to 1 compression. Comp Cams Magnum hydralic 280 cam. This cam has a .480" lift and 280 degrees advertised duration. Intake is an Edelbrock Torker II. Topped with a Carter TQ with .137 rear jets.
401 h.p. @ 5,400 rpm
420 lbs. of torque @ 4,700 rpm
Package four:
360 rebuilt to 9.9:1 compression, Eddelbrock heads, Edelbrock RPM Airgap intake, 750 Eddelbrock carb, Hughes cam HE2430 with 224/230 degrees @ .050", .504"/.515" lift, 1 5/8" headers.
397 h.p. @ 5,500 rpm
436 lbs. of torque @ 3,800 rpm
Package five:
This package is a little more pricey but it is a bolt on package with all parts right out of the box using the Edelbrock RPM parts/package. 360 rebuilt with stock crank and rods, block bored .030" over, 9.5 to 1 flat top pistons. Edelbrock RPM heads, RPM intake, Performer 750 carb and RPM camshaft with .488" lift and 308 advertised duration, installed at 110 intake centerline. Timing was set at 34 degrees total.
399 h.p. @ 5,500 rpm
438 lbs. of torque @ 4,250
Package five-B:
The above motor was tried with a modified Holley carb flowing over 800 cfm and having .076" front jets and .080" rear jets.
430 h.p. @ 5,750 rpm
469 lbs. of torque @ 4,000 rpm
Package six:
Rebuilt 360, bored .030" over with Hypereutectic pistons, bowl ported smog type 360 heads with 2.02" intake valves and competition valve job. Edelbrock Torker II intake, Carter 750 AVS, Comp Cams Magnum roller rockers, Comp Cams custom ground solid lift tight lash cam with .542"/.549" gross lift, 272/276 advertised duration, 243/247 duration at .050" with 108 lsa and a 108 intake centerline. Headers with small 1 5/8" primery tubes.
430 h.p. @ 6,000 rpm
412 lbs. of torque @ 4,900 rpm
Package seven:
360 rebuilt with factory crank and rods, KB191 high compression pistons with 12:1 compression, 2.02" "J" heads ported to flow 260 cfm,Holley 3310 750 cfm, Victor intake, 1 3/4" primary tube headers, Engle Cams solid tappet KV-2 cam with .560 gross lift, 275 advertised duration, 245 @ .050", 110 lobe seperation angle and 106 intake centerline.
450 h.p. @ 6,200 rpm
425 lbs. of torque @ 4,250 rpm
Package eight:
360 rebuilt with 9.5 to 1 cast pistons, original crank, rods and windage tray. 202 heads with competition valve job and ported to flow 260 cfm. Edelbrock RPM intake, Holley 750 rejetted, Large tube headers and Mopar Performance P4120231 cam with .484" lift, 284 duration, 108 lsa, installed at 106 intake centerline.
460 h.p. @6000 rpm
486 lbs. of torque @ 4,250 rpm
Package nine:
360 rebuilt with 10:1 compression flat top cast pistons, original crank turned .010"/.010", rebuilt factory rods. Factory windage tray installed. 2.02" heads with competition valve job and ported to flow 260 cfm. Edelbrock RPM intake, port/gasket matched. Holley H.P. 750 (.076" front, .080" rear jets). Large 1 3/4" primary tube headers. Comp Cams 305AH-8 camshaft with .525"/.540" lift and 305/312 degree advertised duration, 253/260 degrees @ .050", 110 lsa, installed at 108 intake centerline. This motor is a brute for a street car and would only be considered a weekend blaster.
495 h.p. @ 6,000 rpm
500 lbs. of torque @ 4,500 rpm
That's the next plan. Is get the matching comp springs and retainers. Quick question will the rotating retainer exhaust valves work with the new springs and all new retainers. I thought a long time ago a guy posted about the valve lock position was different than the intake valves causing the exhaust and intake springs to be different heights on the smog heads.
If your heads have the exhaust valve rotators I would lose those. They weigh a ton and can hurt rpms.
I don't recall if the valve itself is the same- check to see if it has the same number of grooves on the stem for the keepers.
Those are good heads and have the best exhaust runner for LA style heads.
That article makes me laugh everytime someone brings up making 400hp with a stock headed 340 and a XE268H.
Had real world experience with an engine that was tested at westech then another shop about 2 weeks later. Numbers were not close to each other. The car ran almost spot on to the second shops lower numbers for MPH once it got sorted out a little.
I think the set up at westech is closer to reality now. You can make any software spit out numbers if you know what to tweak in the code/tables. A cheap humidifier can do wonders mucking up the weather stations readings for making great air seem like garbage. I did that to prove a point once or twice. LOL
The dyno's Holdner did with his 360 give useful info for comparisons sake between the different the combos he did. I just don't put much faith in the top end numbers.
The 268XE in a small block mopar is about a 1hp per cube cam when everything else is working as a well tuned combo ie compression, prepped heads, etc.
With a stockish head, this is spot on IMO. It'll make about 1hp/ci when tuned well. Put a really good, strong flowing head on it, you can get in the 1.1-1.15 range
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