Looks so nice and 308s are such a nice sized car that we love em. Classic v12s have that splined crank and I never saw trouble in 28yrs with the cars, I saw lots of trouble with bmws and that awfull keyed crank.Will that front pulley hold up? I grew up in a Pontiac Buick Opel dealership and we burned out every ride. Will that front pulley take t he pounding of continuous full off/on throttle. At high speed interstate work backing off /on throttle @ 130mph really puts a rockin on the piece even being smooth.Have you run it @80/135 continuous on interstates? I really do appreciate your great efforts and would love to splurge but remember the old addage,"if you want a faster Ferrari, buy one"
yes I have run for extended periods of time at high speed and down shifted at 85mph into 4th for passing as well. I've run it for over 6hrs at 90mph with bursts into the arrest me range. no issues at all, I have put it thru 6k miles of grueling abuse from 110*F days to 14*F days. 100 octane racing abuse, full throttle red-line shifts. all of this at 20psi. I wanted to make sure it will stay together when pushed. the pulley is attached to a new mechanical dampener that replaces the stock unit. it is concentrically mounted to the dampener and held with (3) 5/16-24 screws and then the large crank bolt holds the entire assembly to the crank.
I've put about 15k supercharged miles on my including about a dozen autocrosses and there has not been even a hint of a problem with the balance or anything else for that matter.....well the clutch wasn't too happy. My pulley is quite a bit shorter than Scott's, but I've also got a 10 rib belt on mine cranked about as tight as I can get it to keep it from slipping.
Why no need for an intercooler in constant high speed operation?Will the jet tronic compensate @ 20psi or are there mods? Ive done a couple of snapped trans shafts in euro and USA 308s, any comment? Will the ebay kit for $6500 fit my euro 84 german gts?
I have no affiliation with the Ebay kit so I can't answer that one. as to the 20psi, this is a centrifugal supercharger in order to operate at full boost for extended periods of time would require vast amounts of open highway. most of the time i'm operating at 8~10psi with blips into the 15~20 range for brief seconds. when cruising at speed the charger is bleeding boost because the throttle is barely open. under the boost threshold there is little to no strain. unlike a positive displacement blower where boost is constant and available from off idle the centrifugal builds boost in relation to RPM, so at 20psi max it's only 4psi at 3krpm. with the power building in such a manner it's harder to strain the transmission. no intercooler as yet, I'm working on a water/air plenum to replace the stock one. the infrared temps show that the heat from the engine and exhaust into the plenum still exceed the supercharger heat from compression. which is why i want to cool the plenum as well. I could not find any info on the pressure limit for the CIS, I'm running what I'd consider the limit but I don't know. the WUR Ferrari spec'd controls fuel pressure based on boost, vacuum and altitude that is why you can boost these motors with the stock CIS.
I know it kind of looks like that's what I've done, but it's really just the rear-side external view of the machined gear/shaft casing of the particular V9-G model that Scott spec'd out.
Alright, in keeping with the current theme of sharing here's some video of runs I've done. i'm going out this week to do the install on Mike C's 308qv. I'll get some vids of that as well. there will be more added, upload is slow right now. http://www.youtube.com/watch?v=s-w3B6QcaJ8
the tunnel run http://www.youtube.com/watch?v=PoKQebXuVN4 I think any of these would sound more like the real thing with a separate mic out back. the rear engine layout, okay mid, doesn't make it easy.
Sounds great to me - I cannot discern any supercharger whine in yours or Lou's - is that accurate or just my speakers? Would love to hear it from the outside. Great work!
it's weird to me as well but there is no whine. I know that positive displacement blowers will whine due to their nature but the centrifugal should have some, but it's drowned out by the engine noise. the only tip off is the blow off valve which on mine is LOUD due to 20psi and when you shut her off for a brief second the gear whine is noticeable.
So, if I want to do this to my GT4: 1) I have to convert to FI 2) Will all that extra stuff fit in my car?
A point of clarification, please? I thought the point of this was that you could run the supercharger without converting from CIS to EFI? Am I wrong?
no no no, you're right, David is running carbs from what i recall so he would indeed need to run some sort of FI or EFI. this was and is designed to run on the stock CIS. however I'd think that if you were to upgrade to FI from carbs I'd go past CIS and move over to EFI, additional power and better adjustability in tunning. so yes, i got fast and sloppy with my acronyms
Hmmm.. This is sounding intriguing. The idea of converting though, seems a little daunting, if not fairly expensive.. any thoughts?
if going to CIS you'd need all the stock bits. CIS, manifolds, intakes, WUR, injectors, sensors, etc... not sure what that would cost, probably ALOT from a parts place. you might find somebody who upgraded their CIS for EFI and buy their old stuff, providing they sell. I think EFI would run about 3k, check with Mark, aka Mke here, the other insanely boosted 308. he'd know for sure.
Oh right, forgot where he was starting from. My apologies I have a friend with an 82 Mondial who might be persuaded to swap for a carb setup. I can't guarantee that the CIS is currently set up right, though. As a second thought, isn't there someone on here with a GT4 and CIS? Maybe some creative trading there? Just random late night thoughts.
YEAH, MAN!!!! It's very disturbing... I mean I'm so jazzed and eager that it's disturbing my concentration on getting anything else done between now and then! Wednesday is the planned install day, Thursday is tuning and Dyno!
