This was my first time having an engine dynoed and having something built like this. I was pleased with the results, but more happy that things went so well... had to do minimal tuning and nothing went wrong.... carnage, leaks, etc.
All runs were made on straight PUMP GAS - 91 OCTANE.
654 HP @ 6700 (TRQ was 512) (VE% 104.9)
552 TRQ @ 5300 (HP was 557) (VE% 102.2)
The dyno operator thought it needed more carb actually (Dominator 1250 and would get about 20 more HP)
Barry @ Survival provided the Stroker kit, BT MR heads Stage X and Cam
HERE ARE THE SPECS:
Ford FE 390 / 451 stroker
D4TE/ 105 mirror block (stroke 4.25, 4.11 bore - 451 C.I.)(sonic checked very good)
Needless to say, I'm pretty stoked to get 1.45HP per C.I. and on 91 octane. I will scan my dyno sheets tomorrow at the office and see if can get them to post on here, but would be willing to email them if anyone is interested. I can understand if there would be skepticism for sure.
Congratulations on your stroker 390! It would be interesting
July 17 2011, 10:54 AM
to compare your dyno results on another dyno. Not to steal any of your excitement but, my friend bought a used 901 (which I am learning to operate) from a guy who said that there can be as much as 50 HP and TQ swings from dyno to dyno...depending on calibration and cooling methodology. The fact that this was acheived with 91 octane is saying something!
All thing being equal, you will know when you make the first complete pass. Good luck!
1967 Cougar 12.0 Street Car
1967 Mustang S Code FB(in body shop now for final paint)
1968 Mustang GT 350 (next to restore)
1964 Comet AFX 427 Project (for sale)
1966 Comet 428 Drag Car (test & tuning)
Non mi rompere le palle
Every customer wants their engine dyno'd, but then you are compared against every other builder that's on the internet...including the ones with "happy" dynos.
My opinion is, if you do in fact find a "stingy" dyno, then you're a lot better off. I'd rather have a 400hp engine that whoops all the 500hp engines' butts....or an engine with 450hp that runs in the 10's against a 600hp engine that runs in the 11's. It happens.
I think there was an issue somewhere with the fuel or the exhaust. If you ignore the horsepower/torque numbers and just look at the camshaft specs vs the peak horsepower rpm, it seems like that's a lot of cam to only pull to 6700, especially with BT MR heads. I have pulled 428's to 6500 with Edelbrock heads that just had fancy valve jobs....with 20° less duration. A 445-450ci engine is certainly larger than a 428, which will "eat up" a little duration, but those BT heads should be head and shoulders above basic Edelbrocks, even with 390 sized valve packages.
As for the octane requirements, the BT heads certainly have a more efficient chamber. However, I would be very leery about running 91 octane while you're on the street. An engine in a car behaves a lot differently than an engine in a dyno...its loaded differently, outside heat, header heat, etc, etc. With 11.5:1 compression, even with longer advertised durations and efficient combustion chambers, I'd play it safe and run some real good gas.
All in all, I say congratulations on a nice engine.
I wouldn't say that anyone is skeptical, but as they say, the proof is in the pudding. A lot of people have been burnt with overrated street and race engines. A guy brought me a 482ci BBC the other day that had puked. The builder had told him that the engine was 750hp....complete with Procomp heads, factory rods, and a factory GM crankshaft.
B2 Motorsports, LLC
This message has been edited by blykins on Jul 17, 2011 12:09 PM
The dyno operator did say the heads were capable of much more,
July 17 2011, 1:36 PM
The dyno operator did say the heads were capable of much more, but due to the engine displacement (451 C.I.) and RPM limitation (we did take it to 7K rpm, but HP would start falling at 6800-7000, we did not see the point of flogging it past 7000) that's what we were able to get.
No issue with the fuel. Yes, I agree I will have to see how it does on the street and the pump gas may have to be spiked a bit. I do live in Colorado, so altitude is factor and you can get away with running a bit more compression.
was? It's measured in RPS or revs per second. As I understand it, a lower sample rate will give a higher HP rating and vice versa. Standard practice is 300 I believe but could be wrong on all the above. Sounds like a good combination to come up with those numbers with the exception of the comp ratio and low octane fuel. Even at 11.5 I'd expect you'd need more octane. Car info will help with the ET guessing game we're so fond of here.