Howard Jones
Supporter
OK, see ya, Give me a call.
Rear Wheel HP results
- Thread starter Fredy Fender
- Start date
Peter Delaney
GT40s Supporter
A post from one of my mates here in Oz (an RF owner who hasn't been able to overcome the "Not A Valid Host" problem since the new Forum format, so can't log on to post) :
Quote
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I bought a brand new Ford Crate Engine dead stock 302 to suit an automatic trans.-no frills and it had the aluminium GT40 heads. No HP was advertised by FMS except replacement engine etc.
This was fitted to my GT40 with stock 4 barrel Motec EFI - stock crank trigger ignition -pipes running through Cats and quiet mufflers - passed noise drive by at 89dBA -
Audi 016 trans - Rear tyres 255/50/16.
Whilst dyno tuning for emission testing - NOT HP- this engine produced 221 Rear wheel HP @ 5600RPM. Direct 1-1 4th gear. We were not going for state of tune and was running fairly LEAN. Richen it up and the numbers would be 10 to 15 higher. I work as you know for Cummins engine company and see lots of engines on both our water brake engine and wheel dynos.If our diesel engine is rated 400HP plus or minus 5% then rear wheel HP should be 340HP or a 15%
loss. If it does not produce this then we go chasing.
Most engines advertised are metric HP - non parasitic- and do not account for losses.- fans - water pumps - alternators - air compressors -etc. All our engines put out their advertised metric rating. I saw a 430HP marine
engine drop 15 HP the moment the belts and pulleys were hooked up.
The crate engine from FMS in the thread probably does have 345 potential HP but with parasitic loss is 325HP.Less 15% approx. drivetrain loss = 275 Rear wheel HP potential providing ALL other factors are in order - carb-
ignition - timing- exhaust - back pressure- heat rejection- etc etc. A good exhaust helps make the numbers.1" 5/8 versus 1" 3/4 is about 15 - 20 HP alone.
With carb tuning - jetting etc- ignition - pipes - back pressure etc all working in your favour another 50HP would be quite achievable.
The REAL test is street diveable TORQUE. A lot of engines can make big numbers but are an absolute PIG to drive. I will agree with our friend in WA Oz that any car weighing 900kgs and putting down 300 + HP at the rear
wheels is a bloody handfull. Wheelspin at 100kph +
I still go back to the sixties when these things were running cast iron heads - flat tappet cams and antiquated roller rockers and still made 400HP at 6000. Early HiPo 289s made 225HP easy with old technology.Shelby added
bigger cams- bigger carb and a set of headers and got 300HP.NO AFS Heads.
Why does this guy have to go and fit AFS heads to make his numbers look good?????????. I would try a few simple basics first - it just may save heaps $s.
UNQUOTE
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Kind Regards,
Peter D.
Quote
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I bought a brand new Ford Crate Engine dead stock 302 to suit an automatic trans.-no frills and it had the aluminium GT40 heads. No HP was advertised by FMS except replacement engine etc.
This was fitted to my GT40 with stock 4 barrel Motec EFI - stock crank trigger ignition -pipes running through Cats and quiet mufflers - passed noise drive by at 89dBA -
Audi 016 trans - Rear tyres 255/50/16.
Whilst dyno tuning for emission testing - NOT HP- this engine produced 221 Rear wheel HP @ 5600RPM. Direct 1-1 4th gear. We were not going for state of tune and was running fairly LEAN. Richen it up and the numbers would be 10 to 15 higher. I work as you know for Cummins engine company and see lots of engines on both our water brake engine and wheel dynos.If our diesel engine is rated 400HP plus or minus 5% then rear wheel HP should be 340HP or a 15%
loss. If it does not produce this then we go chasing.
Most engines advertised are metric HP - non parasitic- and do not account for losses.- fans - water pumps - alternators - air compressors -etc. All our engines put out their advertised metric rating. I saw a 430HP marine
engine drop 15 HP the moment the belts and pulleys were hooked up.
The crate engine from FMS in the thread probably does have 345 potential HP but with parasitic loss is 325HP.Less 15% approx. drivetrain loss = 275 Rear wheel HP potential providing ALL other factors are in order - carb-
ignition - timing- exhaust - back pressure- heat rejection- etc etc. A good exhaust helps make the numbers.1" 5/8 versus 1" 3/4 is about 15 - 20 HP alone.
With carb tuning - jetting etc- ignition - pipes - back pressure etc all working in your favour another 50HP would be quite achievable.
The REAL test is street diveable TORQUE. A lot of engines can make big numbers but are an absolute PIG to drive. I will agree with our friend in WA Oz that any car weighing 900kgs and putting down 300 + HP at the rear
wheels is a bloody handfull. Wheelspin at 100kph +
I still go back to the sixties when these things were running cast iron heads - flat tappet cams and antiquated roller rockers and still made 400HP at 6000. Early HiPo 289s made 225HP easy with old technology.Shelby added
bigger cams- bigger carb and a set of headers and got 300HP.NO AFS Heads.
Why does this guy have to go and fit AFS heads to make his numbers look good?????????. I would try a few simple basics first - it just may save heaps $s.
UNQUOTE
-------
Kind Regards,
Peter D.
Ross Nicol
GT40s Supporter
I have GT-40x heads on my motor.Before I fitted them I removed all the valves and carried out a mild porting job.Now during this operation I accidentally nicked a valve seat so off the heads went to the machine shop for this to be corrected.Next thing I get a phone call from the machine shop telling me how poorly all the seats have been cut and do I want them to do the job properly? Of course I got them to do it.So this begs the question Were the heads I bought a small sample from AFR where machining was not up to scratch or could HP figures be low, because no one checks they just assume the machining of a set of brand new heads is ok.
Regards Ross
Regards Ross
Ron Earp
Admin
[ QUOTE ]
I still go back to the sixties when these things were running cast iron heads - flat tappet cams and antiquated roller rockers and still made 400HP at 6000. Early HiPo 289s made 225HP easy with old technology.Shelby added
bigger cams- bigger carb and a set of headers and got 300HP.NO AFS Heads.
[/ QUOTE ]
There was a thread on this eariler. Yes, the motors made 400hp however that was SAE gross, quite a bit different from the SAE net we use nowadays. If you want the musclecar heyday era look no more than right now. We've got Corvettes coming off the line with 405 SAE net hp - more than any other engine produced in a Corvette, period, XXX gross engines from the 60s not withstanding. And the track times prove it. Same with the Mustang - latest blown factory version was 390 net hp, much more than any other version sold.
But, I agree with you on the motor, hit everything else you can before swapping those heads out!
I still go back to the sixties when these things were running cast iron heads - flat tappet cams and antiquated roller rockers and still made 400HP at 6000. Early HiPo 289s made 225HP easy with old technology.Shelby added
bigger cams- bigger carb and a set of headers and got 300HP.NO AFS Heads.
[/ QUOTE ]
There was a thread on this eariler. Yes, the motors made 400hp however that was SAE gross, quite a bit different from the SAE net we use nowadays. If you want the musclecar heyday era look no more than right now. We've got Corvettes coming off the line with 405 SAE net hp - more than any other engine produced in a Corvette, period, XXX gross engines from the 60s not withstanding. And the track times prove it. Same with the Mustang - latest blown factory version was 390 net hp, much more than any other version sold.
But, I agree with you on the motor, hit everything else you can before swapping those heads out!
[ QUOTE ]
I have GT-40x heads on my motor.So this begs the question Were the heads I bought a small sample from AFR where machining was not up to scratch or could HP figures be low, because no one checks they just assume the machining of a set of brand new heads is ok.
Regards Ross
[/ QUOTE ]
Were these Ford GT40 heads or AFR (Air Flow Research) heads?
I have GT-40x heads on my motor.So this begs the question Were the heads I bought a small sample from AFR where machining was not up to scratch or could HP figures be low, because no one checks they just assume the machining of a set of brand new heads is ok.
Regards Ross
[/ QUOTE ]
Were these Ford GT40 heads or AFR (Air Flow Research) heads?
Ross Nicol
GT40s Supporter
Gary
Sorry for the confusion in my earlier post.The heads I have on my motor are Ford GT-40X. I got confused as I have been looking at the AFR power figures and I'm very impressed.I may be looking for more power soon as I'm still
5-6 seconds away from the front of the grid.However the car is going well and handling much better.I got as high as 11th place in the races last weekend and left 1 or 2 Ferrari
360's behind and that's a nice feeling in a car I built myself.
Regards Ross
Sorry for the confusion in my earlier post.The heads I have on my motor are Ford GT-40X. I got confused as I have been looking at the AFR power figures and I'm very impressed.I may be looking for more power soon as I'm still
5-6 seconds away from the front of the grid.However the car is going well and handling much better.I got as high as 11th place in the races last weekend and left 1 or 2 Ferrari
360's behind and that's a nice feeling in a car I built myself.
Regards Ross
You can only squeeze so much horsepower out of an engine before the limiting factor becomes the heads. Consider Ford's modular 4.6 SOHC in the Mustang GT. The 96-98 GTs were pathetic...factory rated at 225 hp and with every bolt-on mod available they would make a little over 200 rwhp. In 1999 Ford equipped the 4.6 SOHC with PI (Performance Improved) heads, and the new engine was rated at 260 hp. With bolt-on mods this engine is capable of 280+ rwhp. So the new heads yielded a 35 hp increase; more with a modified engine. Now think about the AFRs and the advertised (and proven) 60 hp increase they can yield.
Bottom line, if you want a few more hp you can probably get it through better tuning (A-F ratio and timing). Most GT40 exhaust systems are pretty good, and would be damn expensive to modify. The intake tract can also be modified for a few more horsepower if you want to clean up and port-match your intake or swap a new manifold. You could probably also pick up a few hp with a new cam. But if you want to see a big jum in hp then you're going to want to pony up the bucks for a good set of heads, like AFR 185s or Vic Jr. While new heads are expensive, I think you'll find them to be cost effective when you calculate dollars per additional horsepower.
Bottom line, if you want a few more hp you can probably get it through better tuning (A-F ratio and timing). Most GT40 exhaust systems are pretty good, and would be damn expensive to modify. The intake tract can also be modified for a few more horsepower if you want to clean up and port-match your intake or swap a new manifold. You could probably also pick up a few hp with a new cam. But if you want to see a big jum in hp then you're going to want to pony up the bucks for a good set of heads, like AFR 185s or Vic Jr. While new heads are expensive, I think you'll find them to be cost effective when you calculate dollars per additional horsepower.
Well, as I mentioned earlier, I am going for a second run, around the end of May. I have not picked up any sets of heads yet. I'll wait and see how the second run goes.
The 302/345 FMS motor is very popular with the vintage mustang crowds. It has also been tested by Car Craft and put out 370HP (at the flywheel). I think Ross brings out an interesting point. The fact that, we don't really know what we are getting from head to head (or from engine to engine).
The guy at the Dyno indicated the FMS crate motors sometimes hit the mark and often did not, could this be because of poor quality control?! /ubbthreads/images/graemlins/confused.gif Evidently Chevy motors did not suffer the same fate (No he was not a chevy fan, Suburus are what they like).
Howard leavs 5 minutes from me and he has the same motor/transaxel. I would not be surprised a bit if his motor would hit the mark (I will go to his house and swap the engines /ubbthreads/images/graemlins/shocked.gif).
I just don't see how I can come up with 50 more HPs with tunning. I really really mean it when I say, I hope I am 100% wrong, it will save me at least $1300 /ubbthreads/images/graemlins/smirk.gif
The 302/345 FMS motor is very popular with the vintage mustang crowds. It has also been tested by Car Craft and put out 370HP (at the flywheel). I think Ross brings out an interesting point. The fact that, we don't really know what we are getting from head to head (or from engine to engine).
The guy at the Dyno indicated the FMS crate motors sometimes hit the mark and often did not, could this be because of poor quality control?! /ubbthreads/images/graemlins/confused.gif Evidently Chevy motors did not suffer the same fate (No he was not a chevy fan, Suburus are what they like).
Howard leavs 5 minutes from me and he has the same motor/transaxel. I would not be surprised a bit if his motor would hit the mark (I will go to his house and swap the engines /ubbthreads/images/graemlins/shocked.gif).
I just don't see how I can come up with 50 more HPs with tunning. I really really mean it when I say, I hope I am 100% wrong, it will save me at least $1300 /ubbthreads/images/graemlins/smirk.gif
Jim Rosenthal
Supporter
I don't know, Faili, I just finished watching two or three weeks of engine dyno testing on a 3l Ferrari Lusso engine converted to GTO specs (cams, pistons, Carillo rods, 6x2bbl Webers etc); the engine always sounded and ran well. First runs produced 235-240hp. Final runs after judicious tweaking of A/F ratios, fiddling with the advance curve in the distributors (note plural) and experimenting with various fuels: engine made 305 hp, limited to 8100revs. On 93 octane pump fuel. But this is a huge proportionate increase, if you think about it, and no hardware was changed. So, working with advance curves, A/F ratios, etc really does make a difference. I think, and hope, you'll see good results and not have to buy new heads. At least, not yet.
I should add: I got my engine as a bare 1968 block. I had no heads, which is why I got AFR- I had to buy something to fill those two spaces up. But clearly they are not the only good head around.
I should add: I got my engine as a bare 1968 block. I had no heads, which is why I got AFR- I had to buy something to fill those two spaces up. But clearly they are not the only good head around.
Ian Anderson
Lifetime Supporter
Back to basics here
Have you checked that when your accelerator pedal is fully depressed that your carburettor butterflies are fully open?
Sounds obvious butI had this snag years ago on a Triumph GT6
I removed the accelerator stop at the pedal and knocked 1.5 secs off the quarter mile!
Obvious but perhaps overlooked!
Ian
Have you checked that when your accelerator pedal is fully depressed that your carburettor butterflies are fully open?
Sounds obvious butI had this snag years ago on a Triumph GT6
I removed the accelerator stop at the pedal and knocked 1.5 secs off the quarter mile!
Obvious but perhaps overlooked!
Ian
When my car was on the rolling road we quit after 5 hours of fiddling around happy with where we had got to. One of the limiting factors was the air cleaner I was using and I was recommended to swap to a K&N filter to get more air in the carb. I was also told that with maybe another three hours of fiddling more power could have been squeezed out of the existing components. We were way ahead of where we started so we stopped there.
With the B303 I think you should be able to get around 290 HP (Dynojet Equivalent) with everything tuned right. The B303 has less lift than the E303. (See http://www.fordracingparts.com/parts/part_details.asp?PartKeyField=1329 for the specs on the cams) One trick would be to switch to 1.7 ratio rocker arms to bring the lift up. Just be sure to check your valve to piston clearances.
Kevin
Kevin
Well,,,,I took the Gt back for another run. Before I post the results I have to mention that after the last Dyno run I found Oil in my coolant /ubbthreads/images/graemlins/shocked.gif. Keep in mind I had 3100 miles on a brand new motor /ubbthreads/images/graemlins/confused.gif BUT, it still runs great, does not run hot and it does everything it did before!!!
Now the results,,, since the last run, I did the following borrowed Howard's exhust (Thanks bro). Re set timming to 36 degree total at 2800RPM (as told by FMS). Set A/F ratio to 12-1. Did only 3 runs.
275 RWHP at 5600RPM (Dynajet), (240 Dynamics)
308 FT Tourque at 3800RPM (Dynajet), (268 Dynamics)
Basically I gaind about 21 more HPs. We could have had done some more stuff. For example the A/F ratio drops to a shade below 11:1 when I get to around 4500 RPM.
Also, my standard GTD pumps puts out 2-3 PSI max. I purchased an equilvalant pump that puts out 6-7 PSI. But, I did not have the time to install it before the run.
I am fairly sure with more tweeking we can get to 285. There is one thing consistant about this motor though,, It takes a dump as soon as you pass 5600RPM.
Any way, I am posting this info incase anyone is interested. I have already started to e-mail Keith Craft, engine factory and 2 other outfits. It is pretty amazing when you tell them "YOUR ENGINE WILL BE REAR WHEEL DYNOED".
The response from some (the ones who have replied!!) is take our HP ratings and deduct 30%. So, if it is rated for 450HP, it will be 315HP at rear wheel /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/crazy.gif
Well, it will still be better than FMS, or will it?!!!
By the way RON, what do you think about having a section for Chassis Dyno (NOT "BS" FLYWHEEL) results? Hopefully it won't be just 4 guys posting /ubbthreads/images/graemlins/grin.gif
As an example, If I buy an engine tommorow from Keith Craft, 347/450HP, wouldn't the members be interested if this thing realy puts out?!
Now the results,,, since the last run, I did the following borrowed Howard's exhust (Thanks bro). Re set timming to 36 degree total at 2800RPM (as told by FMS). Set A/F ratio to 12-1. Did only 3 runs.
275 RWHP at 5600RPM (Dynajet), (240 Dynamics)
308 FT Tourque at 3800RPM (Dynajet), (268 Dynamics)
Basically I gaind about 21 more HPs. We could have had done some more stuff. For example the A/F ratio drops to a shade below 11:1 when I get to around 4500 RPM.
Also, my standard GTD pumps puts out 2-3 PSI max. I purchased an equilvalant pump that puts out 6-7 PSI. But, I did not have the time to install it before the run.
I am fairly sure with more tweeking we can get to 285. There is one thing consistant about this motor though,, It takes a dump as soon as you pass 5600RPM.
Any way, I am posting this info incase anyone is interested. I have already started to e-mail Keith Craft, engine factory and 2 other outfits. It is pretty amazing when you tell them "YOUR ENGINE WILL BE REAR WHEEL DYNOED".
The response from some (the ones who have replied!!) is take our HP ratings and deduct 30%. So, if it is rated for 450HP, it will be 315HP at rear wheel /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/crazy.gif
Well, it will still be better than FMS, or will it?!!!
By the way RON, what do you think about having a section for Chassis Dyno (NOT "BS" FLYWHEEL) results? Hopefully it won't be just 4 guys posting /ubbthreads/images/graemlins/grin.gif
As an example, If I buy an engine tommorow from Keith Craft, 347/450HP, wouldn't the members be interested if this thing realy puts out?!
Howard Jones
Supporter
Hummm.... I would have thought that you would have gotten a little more. Well If it were mine... Recheck valve adjustment, Ya I know it is a hyd cam but re doing the cam followers adjustments doesn't cost anything and if they are loose that might account for loss of breath on the top of the curve, Overly tight exaust valves might do the same thing. Also track down the oil in the water. Oil in the water is consistant with a leaking head gasket. The oil pressure is higher that the water pressure and so the oil has crossed over from a oil passage to a water passage. The same gasket could also be leaking compression unrelated to the oil/water issue. Start with a compression test, one low cylinder would account for the lower hp number. You seam to be making about 320hp est flywheel. 20-30 or so lost in one low cylinder would put you at 340ish and thats about right.
Also, You are sure the secondary's are all the way open right? It will run weak on the top end if the secondarys are not fully open. Could this also cause the fat fuel ratio?
Finally, loud wasn't it?
Also, You are sure the secondary's are all the way open right? It will run weak on the top end if the secondarys are not fully open. Could this also cause the fat fuel ratio?
Finally, loud wasn't it?
I know this may sound a little primative, but how does your 40 drive. Or more to the point, does it feel fast? I'm not one to trust any figures given to me by a dyno, or even a car manufacturer, well not at least until I've done my own tests. I think you can probably get a better idea of how much power your car is really developing by working back with acceleration figures.
Last summer I took by BMW m coupe to the Brighton speed trials. Before the event I used the Car Test computer programme to give me a figure for the 1/4 mile, I used the figures for vehicle weight etc. from the car's log book. The car test programme gave a figure of 13.7secs, I managed 13.9. That's pretty close, and tells me that BMW were giving the correct figures.
Fali, maybe you could go for 1/4 mile, weigh your car etc. and input the detail into Car Test. Or maybe input the figures you've got and get an estimate. I reckon its worth a try.
This year at Brighton, God willing, I will have my MDA. The engine was dynoed at 450HP. The car's final weight will be approx 1050-1100kg. That should give a 1/4 in about 11.5-12.0 secs. If not I know that something isn't right. Especially since I have already proved to myself that Car Test is pretty accurate.
And how about trying a Davies Craig water pump to free up a little more power? I think these pumps represent great value, more HP and better cooling.
Hope this helps.
Regards,
J.P /ubbthreads/images/graemlins/smirk.gif
Last summer I took by BMW m coupe to the Brighton speed trials. Before the event I used the Car Test computer programme to give me a figure for the 1/4 mile, I used the figures for vehicle weight etc. from the car's log book. The car test programme gave a figure of 13.7secs, I managed 13.9. That's pretty close, and tells me that BMW were giving the correct figures.
Fali, maybe you could go for 1/4 mile, weigh your car etc. and input the detail into Car Test. Or maybe input the figures you've got and get an estimate. I reckon its worth a try.
This year at Brighton, God willing, I will have my MDA. The engine was dynoed at 450HP. The car's final weight will be approx 1050-1100kg. That should give a 1/4 in about 11.5-12.0 secs. If not I know that something isn't right. Especially since I have already proved to myself that Car Test is pretty accurate.
And how about trying a Davies Craig water pump to free up a little more power? I think these pumps represent great value, more HP and better cooling.
Hope this helps.
Regards,
J.P /ubbthreads/images/graemlins/smirk.gif
Ron Earp
Admin
[ QUOTE ]
This year at Brighton, God willing, I will have my MDA. The engine was dynoed at 450HP. The car's final weight will be approx 1050-1100kg. That should give a 1/4 in about 11.5-12.0 secs. If not I know that something isn't right
[/ QUOTE ]
Considering that I don't think any of the GTD club have broken into the 12s at Brighton with more hp than your car has (will have) it doesn't seem likely. Something about Brighton and GT40s. From the specs I would swear there should be 11s GT40s there but that is not what I'm told.
This year at Brighton, God willing, I will have my MDA. The engine was dynoed at 450HP. The car's final weight will be approx 1050-1100kg. That should give a 1/4 in about 11.5-12.0 secs. If not I know that something isn't right
[/ QUOTE ]
Considering that I don't think any of the GTD club have broken into the 12s at Brighton with more hp than your car has (will have) it doesn't seem likely. Something about Brighton and GT40s. From the specs I would swear there should be 11s GT40s there but that is not what I'm told.
The car runs fine and it is a lot of fun. I also own a Cobra with a 428CI and 400 Flywheel HP. The Cobra would smoke the GT in Drag racing.
We all buy/build our cars for different reasons. I built my GT for two reasons, LOOKS and DRAG Racing on the STREET.
My Cobra has close to 20KMiles on it and more than half of it is drag racing on the steet. Now, lot of people will say the GT is not for drag racing,,,well, it is If I am the owner. Few broken WIMPY transaxels and engines later,,,it will be /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif
I sometime lurk in on Mustang forums where a lot of real young guys chat. There, everyone Chassis Dynos and posts. Not all of them have great numbers, but just about all of them do post there numbers, high or low.
The new GT has proven to be a nasty dragster. IMHO, bacuse the motor REALY puts out and trany doesn't break. We on the other hand ALL have "2000+lb" cars, "400+HP" cars and can't touch mid 11s. Maybe, JUST MAYBE our HP figures are Bulocks /ubbthreads/images/graemlins/grin.gif
We all buy/build our cars for different reasons. I built my GT for two reasons, LOOKS and DRAG Racing on the STREET.
My Cobra has close to 20KMiles on it and more than half of it is drag racing on the steet. Now, lot of people will say the GT is not for drag racing,,,well, it is If I am the owner. Few broken WIMPY transaxels and engines later,,,it will be /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif
I sometime lurk in on Mustang forums where a lot of real young guys chat. There, everyone Chassis Dynos and posts. Not all of them have great numbers, but just about all of them do post there numbers, high or low.
The new GT has proven to be a nasty dragster. IMHO, bacuse the motor REALY puts out and trany doesn't break. We on the other hand ALL have "2000+lb" cars, "400+HP" cars and can't touch mid 11s. Maybe, JUST MAYBE our HP figures are Bulocks /ubbthreads/images/graemlins/grin.gif
