How much HP's expected from Street ports
#1
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How much HP's expected from Street ports
How much Horse power can one expect from a Street port in a 6 port engine? I want to race a 2nd Gen in RS in SCCA and would be required to run a 6 port. How much can be expected with a Motec or similar fuel injection?
Anybody have any Dyno specs?
This is listed else where also. Really need some realistic HP quotes.
Thanks!
Anybody have any Dyno specs?
This is listed else where also. Really need some realistic HP quotes.
Thanks!
#2
OBEY YOUR MAZDA
Expect some 200-210 flywheel horsepower, I streetported a sixer for my old FC.
http://64.9.213.132/rx7club.com/foru...d.php?t=349280
It had the stock mufflers, which ate quite some hp but it was nice and quiet
http://64.9.213.132/rx7club.com/foru...d.php?t=349280
It had the stock mufflers, which ate quite some hp but it was nice and quiet
#5
Originally Posted by 7thFlame
how much would it be to street port it?
Ron
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street ported 6 port
I personally know of a E prod car in so california. That has a modifyed LARGE street port. and a modifyed S4 Intake that is making 280 + to the flywheel. It has been recently " de tuned" for drivability. But this has taken numerous hours of flow bench testing, burnt up stationary gears,and spent bearings. Probably 6 motors worth. So far, the ceramic seals have not failed though. So it is like the old adage How much HP you require depends on how deep your pockets are. I would think 200-220 would be reasonable on a budget.
#7
I'd like to see the dyno sheet on that car before I believe it. PPorts are usually in the 280+ range. a NA SP will never make that much with 13b or 12A. Feel free to prove me wrong though.
Ron
Ron
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#8
Originally Posted by Flynbryn
I personally know of a E prod car in so california. That has a modifyed LARGE street port. and a modifyed S4 Intake that is making 280 + to the flywheel. It has been recently " de tuned" for drivability. .................... I would think 200-220 would be reasonable on a budget.
Bill Gates' personal budget could not make an E-prod motor make those #'s
#9
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Is that 200 hp range using stock injectors and no mods to the stock manifold & FI electronics?
I was told by JLC Racing in Kent that the most I could expect from a port job on my pure stock 85 SE was 15% because the stock FI and induction couldn't support much more flow that the porting would give. So, assuming about 135 hp for stock plus 15% would give me around 155 hp.
I was told by JLC Racing in Kent that the most I could expect from a port job on my pure stock 85 SE was 15% because the stock FI and induction couldn't support much more flow that the porting would give. So, assuming about 135 hp for stock plus 15% would give me around 155 hp.
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I am scheduled to run my street ported 13b 6 port next wednesday(3/16/05). this is the second run(first was with broken side seals) on the dyno for this engine. I feel the 200hp at the rear wheels is very possible and I would like 225hp. I have heard rumours that some of the e production guys have gotten as high as 250hp at the wheels. If all goes well I'll post the results. the first run with the blown side seals resulted in exactly 100hp and that was with 3 of the rotor faces with 0 compression or basicly half and engine.
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I'll update everyone. I did not make the dyno test. The engine decided to act up the weekend before the test. I fixed the small problem with the ignition and I am scheduled to test again this coming friday,3/25/05. You don't have to worry about me not doing something. I will be at the dyno this friday. I may not rush home to my computer to fill you in, but I'll be there. I have run this car twice on a chassis dyno and each time there have been problems with the engine, so no need to post any results. Last time with two blown side seals it made 100HP at the wheels. The E-production guys running carbs are making 250HP to the rear wheels easily. unfortunately the EFI engine can only use the OEM intake manifold and throttle body. the carb engines can use any manifold and are allowed 44 or 48mm chokes(I can't remember which) this is very large and the shorter manifold they use is much better than the OEM intake. if the EFI engine could use a shorter custom manifold they could easily make the same HP number.
#14
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I don't know about a 13b, but I do know that a 12a is capable of 230-240hp on the engine dyno. According to my sources this range is about all that can be had, ceramic seals and a large street port. Most using Weber IDA's fully flow tested, ported/polished intake manifolds with the best exhaust made.
If anyone is making 250 rwhp, let me in on your secrets.
If anyone is making 250 rwhp, let me in on your secrets.
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OK - I run an EP 12a and I have heard recent dyno rear wheel numbers from a competitor who runs a national quality 13b and I can tell you that you are WAY off base. There is NO ONE running a legal EP rotary that is getting anything like 250 rear wheel horsepower. This sound a lot like one of those "I heard from my buddy's cousin that you can get 300 hp with one of those new cyclone intake" kind of stories. Believe me, you're not close.
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As for legal that is always a question. I do know that more than one of the engines were run at the runoffs and went through the tech and inspection. I realise this does not guarantee it is legal but it was raced. I have heard the HP numbers from more than one competitor and they were all first hand accounts. They could have also been stretching the truth a bit also but they have all been very successful with their setups too. If my test is successful(engine survives) I'll post my results. And for sure my engine would be absolutely legal. In fact it is very tame compared to others. No ceramic seals or trick lightened(sp?) rotors.
#20
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Originally Posted by tims
The E-production guys running carbs are making 250HP to the rear wheels easily. unfortunately the EFI engine can only use the OEM intake manifold and throttle body. the carb engines can use any manifold and are allowed 44 or 48mm chokes(I can't remember which) this is very large and the shorter manifold they use is much better than the OEM intake. if the EFI engine could use a shorter custom manifold they could easily make the same HP number.
#21
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Take a look at the EP trap speeds from this years runnoffs. I know Trash is legal. He had trap speeds of 130. I don't know Neal and I'm not sure if he was running a 12a or 13b, but he was the fastest 1st gen with a trap speed of 133. Who is the guy with 250 rwhp?
http://www.scca.org/_Filelibrary/Fil...n-traps-ep.pdf
http://www.scca.org/_Filelibrary/Fil...n-traps-ep.pdf
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Bob Neal is a good friend of Dave Lemon from Mazdatrix and is a very good driver. I believe he is running a 13b. Did they reduce the choke size recently for the carb engines? I said before I don't keep up on all the rule changes. These numbers were stated after the SCCA had increased the choke size for the carb engines. If they have since reduced the choke then HP levels are likely lower. I was putting my engine together early 2004 so things have likely changed since then. The one FI engine builder was still claiming similair numbers but they could not get it to last the whole race and the driver was not as talented as some of the other regulars so it never showed during the race. I have seen the lap times at some of our local tracks start to come down recently so something is happening.
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Originally Posted by tims
Bob Neal is a good friend of Dave Lemon from Mazdatrix and is a very good driver. I believe he is running a 13b. Did they reduce the choke size recently for the carb engines? I said before I don't keep up on all the rule changes. These numbers were stated after the SCCA had increased the choke size for the carb engines. If they have since reduced the choke then HP levels are likely lower. I was putting my engine together early 2004 so things have likely changed since then. The one FI engine builder was still claiming similair numbers but they could not get it to last the whole race and the driver was not as talented as some of the other regulars so it never showed during the race. I have seen the lap times at some of our local tracks start to come down recently so something is happening.
A correction to my last post.....Trash should have read Thrash as in Tom Thrash.....sorry Tom.
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Most have said that the Carbs are only getting about 210hp at the rear wheels. Now the EFi guys should be getting about 225-235 at the rear wheels. I know of 2 EFI motors that have reached those figures and have not blowen-up. Yes they have probably spent about the same on those engines as most people would have spent on there entire race cars.
We all have to remember though, that what one engine dyno readings say don't mean the same on the other side ofthe US. I also no that some figures have been based on Engine Dyno's then calculating the horsepower loss thru the drive train. You have to compare the same set-up. (i.e. same weight flywheel, same clutch unit, same transmission gears and rear end ratios. Also needs to be tested in 4th gear. Some dyno operators run cars in third gear to get it to spin up faster.)
We all have to remember though, that what one engine dyno readings say don't mean the same on the other side ofthe US. I also no that some figures have been based on Engine Dyno's then calculating the horsepower loss thru the drive train. You have to compare the same set-up. (i.e. same weight flywheel, same clutch unit, same transmission gears and rear end ratios. Also needs to be tested in 4th gear. Some dyno operators run cars in third gear to get it to spin up faster.)
#25
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your right about the dyno numbers and also some dyno shops will use corrected HP numbers. the dyno will correct the HP numbers based on the ambient air temp and other things. That is why I do all pulls in the gear which is 1:1(4th on my current gearbox) and I don't use an correction factors. I also like to use the same dyno but this has been a problem. I have yet to use a shop that when I left I felt they knew more about the dyno than I did. Seems like alot of shops have bought the equipment but never learned how to operate it properly. The latest shop comes highly recommended and has a good track record, so we will see. I will give all details after I have finished the testing and tuning.