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I always know I can get an honest opinion here. :)
I know that pulleys are free in IT (except that the same type of belt is required) but I am curious if the claim that you can gain 12hp from changing pulleys is true and if it is true... how! below is a link for the specific example I am talking about.
Thanks,
Stephen
http://srmotorsports.com/RX8_Power_Pulleys.html
You betchya!
12hp from Pulleys.
15hp from a CAI.
5hp from a Grounding Kit.
20hp from Headers (any header).
20hp from a Dynomax muffler.
That's 72hp right there!
different engines gain different amounts using underdrives. it's quite possible that this is true, but I'd recon it's not likely. maybe a Steve E type will weight in with a lot more experience on the rotaries.
either way, underdriving water pumps and alternators is usually a good thing - they are typically designed for peak operation around the 2-4k RPM range. meaning the alt becomes a big drag (and you are using it less than in stock trim, too, so it's really unneeded drag) and the water pump can cavotate and let you overheat (somtimes without showing on your gauges, depending on where you plumbed in the sender).
watch the water pump underdrive as you might have to hold 4k RPM on grid/track to keep the car cold - pace car periods, grid, cooldowns you have to stay on top of the temps and drive higher revs than you might think are appropriate. we rebuilt a motor for a guy that had a high water pump underdrive (moved water from ~4-7k RPM). between the extra heat the motor was now making (accompanied by more ponies) and the operational RPM of the pump, he overheated it first time out staying ~2k RPM in 5th on his cooldown lap. there's irony for you.
If all I could get out of a stock RX8 was 172.5 I could find you 20 hp with a pulley setup and a new set of plugs.:D We have seen 5 hp when you dump the BIG stock crank pulley and run an oversize water pump setup. Pretty much standard practice because the stock setup is designed to run 5000 rpm off race numbers.
Pick the target RPM of the water pump to get adequate flow and size the setup to hit that at the low end of your power band. Then let the HP fall where it may. Extra heat will rob any gain you see running too slow.
What is a Steve E type? (Ducks as he waits for Smart A reply)
This was more informational than I thought it would be... I never gave any thought to the lower rpm concerns with cooling. Thanks everyone!
Betemotorsports... you forgot the sticker that adds in a few more ponies!
Steve, since your the only other person I have heard of with an RX8 under construction and we most likely will always race in seperate parts of the country maybe you can give me some pointers : ) pm me anytime and maybe we can chat! Are you going to Miller motorsport park with speedsource?
Stephen
PS: as far as a Steve E type... I don't know you well enough yet!
the type of guy who will sell you new plugs and pulleys and promise a 20hp gain :pQuote:
Originally Posted by seckerich
Makes no difference if you are racing here or somewhere else, glad to help you out. I will be at Miller on the 69 car so look me up.Quote:
Originally Posted by StephenB
I knew you could not pass that up Chip.:D
so maybe the weight for your car is right? :blink:
No, weight is still a little high for HP/weight for the class but the "package" is raceable at the current spec. After we have some 10/10ths builds it will be pretty close. I would just rather shoot myself than mental masturbate that subject on here again. :dead_horse: Have fun.Quote:
Originally Posted by tom91ita
I gotta imagine that switching from stock steel pulleys to the aluminum aftermarket stuff also helps simply by the reduction of MOI...
:lol::OLA:
Quote:
Originally Posted by Andy Bettencourt
That sir is outside IT's core principles, and would lead to a significant expansion of performance thresholds. If these were allowed the CRB would have to take a long hard look at beefing up the cage rules.:D
I was thinking this would fit in the SIR on the BMW and get back all the lost power.:D
The real trick is to use magnets around the SIR to get the ions right.Quote:
Originally Posted by seckerich
Put it between your lips and blow?
You just need Rapid Force Technology! http://rapidforceexhaust.com/
FYI... these guys were headquartered in my business complex but I think they've gone bankrupt. Their test car was an old ex-police Crown Vic that's still sitting here in the parking lot, held in place by 10,000 spider webs.
"I will be at Miller on the 69 car so look me up."
Fly-in guys....probably 1st class, while the rest of us drink 3.2 beer
Stephen B. if you're on the west coast the following weekend, Sevenstock is in Irvine Ca. It'll turn you into a real rotorhead
Congratulations on a great job at the speed trials. We give you guys a lot of crap on here in jest, but really proud to see some IT guys do well. Give us a report when you get a minute. :023:Quote:
Originally Posted by GKR_17
If it is the beer I think, it has been in the cooler for a year!! Wine and cheese and always the center seat. See you at Miller Jerry you lurker.Quote:
Originally Posted by HOOSER 99
I just purchased a set after breaking the fiber water pump pulley. I figure it'll help recapture some of the HP I lost by going back to the correct application intake manifold, (btw, that was ~12hp) But for my application the pulleys are haft that price.
Word travels faster than we did! It was a complete circus, nothing like a normal weekend at the track as we're used to. Spent most of the time waiting in line, or in impound. Only made 7 runs over 5 days, but got the results we'd hoped for. Pop set a new record at 149.5 right away, and then Ben bumped it a bit higher to 153.5 after we made a few minor setup changes. Still need to vacuum the salt out of the van...Quote:
Originally Posted by seckerich
http://www.mylaps.com/profiles/image...2404139733.gif
[ame]http://www.youtube.com/watch?v=_oo492S4Gt0[/ame]
[ame]http://www.youtube.com/watch?v=1O7EwN8n5U0[/ame]