MRL Performance 340, WOW!

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Well if nuthin else, it sounds good.
 
340's rule!, Bought a numbers '71 340 Cuda in 1980 as a stock street car with 3.55's, it had small headers, a .484 purple hyd. up it, low rise intake and a 750 Holley, a Super Holeshot 3500 verter, that ran 13.3's on 8x26" slicks, thought I could better that some......

In went a DC.590 solid cam, 4.30 gears, Strip Dominator, 2" spacer, 850DP, (went slower with a 750!!) 4200T/A verter, 10x28's, 1.3/4" Hedman Chassis hdrs, a snubber, stock springs, this was with stock unported 2.02 heads, only revved it to around 6300, result> 12.39@108 at approx 3600lbs at the line (all steel car), worked it out to be around 374 track hp, nothing amazing but it always used to pull a wheel up, I could feel the torque, put a lot of 440 cars to shame back then, terrific engines, responded well to absolutley every mod if thought about before adding. Oh the 11.01 was with a 250 shot. Learnt some since then, you can see it wrap the tyre as only 10psi in them.

I'm tempted to get back into Racing again and would certainly Use Mike for 630hp+ SB Motor, put it in a 3000lb A-body and still even today wipe out a lot of the BB stroker boys over here who mostly, not all, only seem to muster 10.3's in similar weight cars with anything up to 512cubes!!!:???:
 

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Mike, first, Im a fan of your work from the other side of the pool. You make mopars scream.

You said earlier that nowadays the rings seat after just one pull. May i dare to ask if that is caused by better macine-work or the piston/ring material package or both?

Iwe always done backyard enginebuilding, and my engines always liked oil, no rebore/honing just new rings. Now, on my new build i have decided to spend a full bore/hone/piston/rings job on it, is it important that i check around and use the company that has the newest machine, or would a old german bench with good tools do a proper job?

Engine ring seal problems has to be a place where some big power may dissapear...

Really nice 340!:happy1:
 
It's been 2 years since I asked about track times, have you made it to the track yet?
 
Nope. Moved this past year and didn't have any time to do that - by the end of the season I was just getting a really good tune in the ECU with the EFI that's on it now.
 
mopowers said:
When can we expect some 1/4 mi MPH numbers??? Seems to be a lot of skeptics around here...
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That's everybody's job! Be a jerk and call you out on it. Don't forget failure to perform leads to scorn and ridiculous never ending bad mouthing. On how bad you suck, can't tune, with advice or throw more money at it or your a cheap bastard!
LMFAO!
 
rumblefish360 said:
That's everybody's job! Be a jerk and call you out on it. Don't forget failure to perform leads to scorn and ridiculous never ending bad mouthing. On how bad you suck, can't tune, with advice or throw more money at it or your a cheap bastard!
LMFAO!
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LOL! On the otherhand maybe the OP goes out and runs 120mph in the 1/4. I tend to be a little skeptical over the big hp number though. Only one way to find out...
 
Street mannered Pro-charged small "factory" block stroker ? That is where it is at these days ...
 
Okay, well I'm not really sure, I might get a chance to go to Lapeer Dragway (not the best place) this year. Also, I gotta let you know I had to repair the trans because the bearing retainer failed over last summer the little I got to drive it. It runs a lot better than in the original video, I have no reason to be skeptical, the thing really, really hauls. Guess I'll need to shoot another video sometime.

Not really sure exactly what I would expect on the strip, 275's all around, 18" wheels, and I bet the car is on the heavy side for a-bodies.

In any case, Mike has sold a lot of engines that were run on the same dyno and also run at the strip, I'm sure there's some info out there.

Since you're skeptical, please enlighten me on what the cork would be? Not too many people have lightened up rotating assembly, roller cam, beehive spring stock stroke 340s - and I'm sure we gained some flow with the valve job. Now I even have a super victor EFI manifold with port injection and a 1000cfm throttle body.
 
goldduster318 said:
Okay, well I'm not really sure, I might get a chance to go to Lapeer Dragway (not the best place) this year. Also, I gotta let you know I had to repair the trans because the bearing retainer failed over last summer the little I got to drive it. It runs a lot better than in the original video, I have no reason to be skeptical, the thing really, really hauls. Guess I'll need to shoot another video sometime.

Not really sure exactly what I would expect on the strip, 275's all around, 18" wheels, and I bet the car is on the heavy side for a-bodies.

In any case, Mike has sold a lot of engines that were run on the same dyno and also run at the strip, I'm sure there's some info out there.

Since you're skeptical, please enlighten me on what the cork would be? Not too many people have lightened up rotating assembly, roller cam, beehive spring stock stroke 340s - and I'm sure we gained some flow with the valve job. Now I even have a super victor EFI manifold with port injection and a 1000cfm throttle body.
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I think a lot of folks are a bit skeptical because the number generated by the dyno seems a bit high for what they'd expect from that combo. The only way to shut them up (me included) is to weigh the car and show a time slip. The MPH will be the key.

From what I've seen, the members on this site who've touted big hp numbers from that dyno haven't had a timeslip with a MPH that matched up. As long as you're happy though, that's all that matters.
 
Well, if you can look at it this way, the heads are likely flowing numbers like a stock LS1 chevy, we got the rotating weight into the ballpark, run a similar cam size cam for one of those, not uncommon to see 400 rwhp and 370 rwtq from a combo like that. The whole idea behind building the engine this way was to use a lot of the ideas you'd find in a more modern engine. It's also a car that won't ever have drag radials or slicks on it so building a stroker motor would have only turned it into a burnout machine.

Comparing this to a flat tappet cammed motor with stock rods, double springs, and TRW L2316F's isn't even a fair comparison. There's a lot more area under the curve with a roller cam of the same duration. This thing also has great quench. I know we took at least 800g out of just the rods, and a ton more out of the pistons vs stock.
 
I'm a skeptic. There's nothing wrong with saying "prove it". Thing is, the only way to prove a number produced on a dyno, is to accelerate a given mass, over a measured distance, with an accurate method of measuring the speed, and calculate how much power it takes to do it. Now there's nothing against any builder that uses a dyno. We all love the numbers and as the guy who puts it together, the dyno is a great way to see if things are doing what you expect. Problem is, at least in my opinion (skeptic's), is a dyno cell is not a chassis. Most are set up for ease of setup and removal. So they have their own water supplies, their own fuels sypply, their own big, long tube, smoothly bent headers dumping into big resonators or right out the wall, and a smooth bell that isused to measure the amount of airflow going into the engine (critical job). All of which make access and setup easy, all of which will skew the actual numbers to a degree. Dyno software and calibration can also be manipulated, or simply not really paid much attention to which can also skew the numbers. The fastest way to take 30-50 horsepower off a "500hp " engine is put it in a chassis. Where it has to pump it's own fuel, drive it's own water pump and alternator and maybe power steering and AC, run at 190°+ water temps, breath in through an air cleaner assembly, and push gasses out through smaller, more severely bent headers, 10' of pipes, and mufflers. The engine is still a great engine. But the realistic power level is not what the dyno showed. The performance at track will tell what that engine does in a real situation. Dynos are tools - not "truth".
 
Gold - again - not trying to make light of any of your investment or Mike's ability. Everything you mention above only points to potential power production, and the dyno number backs your ideas up from what I can see. But the dyno is simply not how the engine is actually being run as it sits in your car.
 
moper said:
I'm a skeptic. There's nothing wrong with saying "prove it". Thing is, the only way to prove a number produced on a dyno, is to accelerate a given mass, over a measured distance, with an accurate method of measuring the speed, and calculate how much power it takes to do it. Now there's nothing against any builder that uses a dyno. We all love the numbers and as the guy who puts it together, the dyno is a great way to see if things are doing what you expect. Problem is, at least in my opinion (skeptic's), is a dyno cell is not a chassis. Most are set up for ease of setup and removal. So they have their own water supplies, their own fuels sypply, their own big, long tube, smoothly bent headers dumping into big resonators or right out the wall, and a smooth bell that isused to measure the amount of airflow going into the engine (critical job). All of which make access and setup easy, all of which will skew the actual numbers to a degree. Dyno software and calibration can also be manipulated, or simply not really paid much attention to which can also skew the numbers. The fastest way to take 30-50 horsepower off a "500hp " engine is put it in a chassis. Where it has to pump it's own fuel, drive it's own water pump and alternator and maybe power steering and AC, run at 190°+ water temps, breath in through an air cleaner assembly, and push gasses out through smaller, more severely bent headers, 10' of pipes, and mufflers. The engine is still a great engine. But the realistic power level is not what the dyno showed. The performance at track will tell what that engine does in a real situation. Dynos are tools - not "truth".
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Yeah, but big numbers sell engines.
 
mopowers said:
Yeah, but big numbers sell engines.
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This is REALLY the reason I get curious at times, not to question a guys project, but if someone buys a engine, based on a "inflated " dyno number, I sorta feel like that's lying, or at least being unethical.....Most people understand the losses from drive train and all, but if the engine is 100 HP shy, then you say hmmmmmmm... I would point out, I am not making reference to any engine in THIS thread, just so we are clear
 
I could care less about the #'s, a reliable build is what I like , with the right parts and quality never hurts.
I'm looking forward to your next build Mr Liston, the #'s are in your recipe.
 
A similar situation can/has occurred with some of the cylinder heads shops....some head porters are better than others, but if you get a shop who suddenly has numbers much better than everyone else's, on several different head types, it could be a "sales tool"
 
lets get back to converstion at hand ..... but ... if you want proof of what Mke's dyno results ... did he not build a stroker for a BLUE 70 dart ... around 500-530 HP ... i think the guy had it at the track and ran around 11.50's...sounds right to me ...
 
rrvolare said:
lets get back to converstion at hand ..... but ... if you want proof of what Mke's dyno results ... did he not build a stroker for a BLUE 70 dart ... around 500-530 HP ... i think the guy had it at the track and ran around 11.50's...sounds right to me ...
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Yes, a beautiful dart it is! I think the mph in the 1/4 was 114 or so, which definitely doesn't seem right for 530 HP.
 
Again - my comments are not in any way a questioning of Mike's abilities. It's about scientific proof vs. extrapolated info. It's about what is more important to an enthusiast: fact or fiction? If one sees a car at a cruise night and it looks and sounds fast, or one sees it at the track and the scoreboard flashes an ET & MPH?
In the Dart above - using the HP chart off Moparts which IIRC is basically the old-school and time-proven Moroso HP calculator - '70 Dart V8 curb weight is 3090lbs. Minus 30-50lbs for aluminum parts, and an assumed 200lbs driver so - 3250lbs. Rounding up to 3300. 1/4 mile speed of 114+, round up to 115. HP is indicated at 392 at the tires. I use 15% for manual trans, 18% for these vintage Torquefilte or C4 autos (more for other automatics). I'm assuming the car above is automatic. 392 x 1.18 = 462.5. That's "the numbers" as I would figure them. Still very stout for a small block stroker. Still a smiling customer. Still a talented builder. But not "530hp". The dyno didn't lie. The dyno said the parts are working well together and Mike did his job and with the dyno setup it makes 530. That's what a dyno is supposed to do. That's the EXTENT of what a dyno does. The way to make the dyno as accurate as it could be is to hook up the engine and run it in exactly the same way, using the exact same equipment as it will be run in the chassis. That's what the carmakers have to do in order to advertise horsepower figures. But they are forced to do so and the cost is spread over the unit cost of the engine package being tested. Most dyno rooms cannot accommodate all that, nor small businesses afford to spend all that money on equipment and time without charging the user for it.
 
moper said:
I use 15% for manual trans, 18% for these vintage Torquefilte or C4 autos (more for other automatics). I'm assuming the car above is automatic. 392 x 1.18 = 462.5. That's "the numbers" as I would figure them.
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But it still doesn't take into account that on the dyno it is just the engine, often with an electric water pump etc. Installed in the car there is air cleaner, full exhaust, water pump, alternator and what not. It's like the endless discussion of gross and net horsepower. So it is much more than just 18% loss, realisitically.
 
stixx said:
But it still doesn't take into account that on the dyno it is just the engine, often with an electric water pump etc. Installed in the car there is air cleaner, full exhaust, water pump, alternator and what not. It's like the endless discussion of gross and net horsepower. So it is much more than just 18% loss, realisitically.
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You're correct Stixx, but my problem is the cases where the dyno 2 dyno numbers are more than 1-2% off . IE Dyno 1 says 480 hp and same engine on Dyno 2 says 520 hp that's almost 8.5% difference. I am not saying that's the case here but if you watch this stuff like a hawk like I do you can find many examples. Always watch the tq/ci figure. There are 3 dyno shops in my area and the one that makes the customer the warmest and fuzziest is the busiest. Hint--It ain't mine. J.Rob
 
stixx said:
Sad, but better be honest. Hope there is still a few people who also appreciate this.
Btw. really like your build stories. :thumbsup:
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You're right it is better and yes I have been asked to fudge the numbers--I decline every time knowing it's a slippery slope.

Thanks, and I will have 2 or 3 coming shortly. J.Rob
 
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