4.5L Owners Thread - DeMan Motorsport
07-30-2020, 06:19 PM
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4.5L Owners Thread - DeMan Motorsport
We thought it would be beneficial to create a thread dedicated to the progress of our 4.5L Cayman GT4 package and have a place for current owners to connect with each other and share their experience with the 4.5L transformation. It is also a place to ask questions you may have.
Update 5-4-21: Matt Farah drove the 4.5L GT4 and did a full review for the Hagerty "Modified" show.
Update 11-19-20: Road and Track recently came for a visit to the shop to check out the 4.5L and many of you came by for a get together. Here is a link to the article and awesome photos. https://www.roadandtrack.com/car-cul...-gt4-45-liter/
Our 4.5L has now even made its way to Thailand and installed by Autowerks Bangkok. They were kind enough to share a build recap from start to finish. You can check it out on our youtube channel here:
We will post some recent feedback from other threads and encourage the 4.5’ers to check in.
Update 5-4-21: Matt Farah drove the 4.5L GT4 and did a full review for the Hagerty "Modified" show.
Update 11-19-20: Road and Track recently came for a visit to the shop to check out the 4.5L and many of you came by for a get together. Here is a link to the article and awesome photos. https://www.roadandtrack.com/car-cul...-gt4-45-liter/
Our 4.5L has now even made its way to Thailand and installed by Autowerks Bangkok. They were kind enough to share a build recap from start to finish. You can check it out on our youtube channel here:
We will post some recent feedback from other threads and encourage the 4.5’ers to check in.
__________________
Shop new and used parts in our NEW Online Shop
Check out our latest 4.5L Cayman GT4 Upgrades
See all cars for sale HERE
See awesome photos of out projects here.
DeMan Motorsport
530 N Highland Ave Nyack, NY 10960
845 727 3070
Porsche Sales, Service, Restorations
Porsche Race Services and Parts
DeManMotorsport.com
Shop new and used parts in our NEW Online Shop
Check out our latest 4.5L Cayman GT4 Upgrades
See all cars for sale HERE
See awesome photos of out projects here.
DeMan Motorsport
530 N Highland Ave Nyack, NY 10960
845 727 3070
Porsche Sales, Service, Restorations
Porsche Race Services and Parts
DeManMotorsport.com
Last edited by DeMan Motorsport; 05-04-2021 at 04:10 PM. Reason: new video out - formatting
Popular Reply
02-18-2021, 11:25 PM
Rennlist Member
Surprised it took almost a year since many of us started our builds for a dyno debate to show up about the 4.5L's, but hey we got here 
. +1 to @ajw45 's post above, there are a few things here that are the most critical regardless of this being 560hp or 528hp or wherever you want to peg it based on the day, the temp, the configuration of exhaust goodies, the type of dyno, blah blah blah blah
Here's my TLDR from a guy who's a year into ownership:
. +1 to @ajw45 's post above, there are a few things here that are the most critical regardless of this being 560hp or 528hp or wherever you want to peg it based on the day, the temp, the configuration of exhaust goodies, the type of dyno, blah blah blah blah- The shape of the TQ and HP curves are crazy good
- The torque is instant on paper and behaves that way in real life. The car moves like it has a high strung V8 in it.
- The stock HP dips and flat spots are loooong gone, its up and to the right and delivered in an incredibly usable way.
- Nobody is feeling the difference between 488hp and 500hp, but maybe you all have more sensitive butt dyno's than me
- The delivery of said power is deceptively functional
- Often over-looked with big builds like these is the tuning. We all don't mention it because the drive-ability is so good that we usually just forget. The car basically behaves as stock regardless of gear or RPM etc. That's REALLY hard to achieve given the increases in power we're talking about.
- My car is probably on tune V4 from a year ago....V1 was FINE. Nobody tells Elon Musk to stop updating their Tesla so who am I to tell Rick no
- It's as fast as we all say it is or sure as heck feels like it's that fast
- It's a shame I didn't film it, but over the summer I did multiple runs from 60mph to deep into the 100mph+ range side by side to my buddies 991.2 GT3 with a PDK. As a former heavy track user with his GT4, which had all the bolt-ons done, he knows what a GT4 can do out of the box and modified far more than even I do. The result of the pulls? He was laughing his *** off and the first words out of his mouth were "that's every bit 500hp at the wheels and it's insane to see that in a GT4".
- Qualitative details on the pulls
- You could easily see the ebb and flow of the cars behaving during the pulls - he had more redline, I had shorter gearing, he flicks a paddle faster than I row a gear etc, but every single time the 4.5L pulled some ground when we did 3rd-5th. If we did a 2nd through 5th he got the jump due to me being out of gearing instantly and I had to play catch up. But he did not walk away even with that jump. I'll take that ALL day long in my little mid-engine baby GT car.
- Depending on the run maybe half to a full car length is what I could gain. It's all anecdotal so take it with a grain of salt. Do I shift gears hard and fast? Not really. Do I usually drive like a wuss (which @Rick DeMan constantly scolds me about)? Yes
Was this surprising to both my friend and I and proved Rick's point to me about how fast the car is? Yep.
- Qualitative details on the pulls
- Internet is gonna internet, but for those that care if it helps justify my friends opinion (cause frankly mine is 100% worthless) he also owns the whole fleet of GT cars (of course some F cars too) and puts miles on them. So he knows what's up without much debate in terms of speed, power delivery, etc etc when a car is kick ***. The 4.5L blew his hair back. Enough said.
- It's a shame I didn't film it, but over the summer I did multiple runs from 60mph to deep into the 100mph+ range side by side to my buddies 991.2 GT3 with a PDK. As a former heavy track user with his GT4, which had all the bolt-ons done, he knows what a GT4 can do out of the box and modified far more than even I do. The result of the pulls? He was laughing his *** off and the first words out of his mouth were "that's every bit 500hp at the wheels and it's insane to see that in a GT4".
- $ per HP/TQ is a bargain
- The way I see it you have two paths if you want to mod your GT4 or any N/A car for that matter
- Option 1 = bolt-ons all at once or piece meal. Take this route and you're going to spend $18-20k on parts plus a few grand for install. Let's call it $25k all in for sake of argument. With that you're probably going get close to what, 400hp? That's not a bad thing. It cleans up the horrendous flat spots in the power curves from the factory that we all complain about and makes it more of the "it's what it should have been from Germany" kinda thing. I dig it, who wouldn't?
- Option 2 = Hog wild, stroke it, bore it, do the damn thing, drop the $30k.
- Even if the dyno charts are only 90% accurate or reliable or whatever you wanna call it the math holds up. It's something like 20% cheaper per HP taking this route. @Luca Paindelli made a whole spreadsheet on this IIRC and then @Rick DeMan confirmed this with a few cars that came in with all the bolt-ons on and decided to bump up to the 4.5L.
- Both are cool, just pick your spend level and desired power. There's no sugar coating this though, 500hp has moved the car from "this is cute and kinda fun even at 8 or 9/10ths" to "I could get into some serious s$%t at 3/10ths". I have zero regrets openly saying I had a few clench moments over the summer burying the throttle.
- The way I see it you have two paths if you want to mod your GT4 or any N/A car for that matter
Here's my TLDR from a guy who's a year into ownership:
- @Rick DeMan has built a hell of a product and is getting the global order volume he deserves. God speed man, it's only gonna get worse.
- Someone will correct me if I'm wrong, but I think there's like 30 street focused 4.5L's floating around all putting down nearly identical power and with nearly identical owner responses. That's a pretty good number for an analysis! If we were having issues with the builds, or they didn't meet our expectations, or we felt they weren't worth the money, or if Rick's work and customer service was sub par, or if there were wild fluctuations in the performance numbers, it would have called it out by now.
- Smash the like button below? J/K
- As far as I'm concerned someone can pry my 4.5L out of my cold dead hands whether its 488hp or 506hp
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Rick DeMan (08-03-2020)
07-31-2020, 12:52 PM
#3
Three Wheelin'
Yay! I hope to become an owner one of these days but for now my Deman 4.0L X51 is still running strong after 15k miles, track days, Smokies events, road trips, and just commuting back when that was a thing pre-covid.
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Rick DeMan (10-23-2020)
08-01-2020, 02:05 AM
#4
Hi everyone. I'm the owner of the 4.5L conversion in Thailand. I have been following Rick's engine builds since the 4.0L version. When I saw the 4.5L and hearing Rick say it was probably the maximum for that engine, I decided to pull the trigger. Being halfway across the world has its challenges for doing this build. However the guys at Autowerks Bangkok together with Rick's excellent service made the whole process a breeze. The install went very well. I did the 4.5L engine, short gear transmission and clutch kit.
The first drive was nuts. The power combined with the shorter ratios completely transformed the car. The GT4 was already my favorite driver's car in my collection. Rick's mods took it to the next level.
The only issue we had was with the poor fuel quality of the pump gas here in Thailand. I started off running the car with race fuel. Now Rick and Autowerks are working on a new tune to run with the pump gas here. Once that's done I'll be back with more feedback.
If anyone is thinking about doing this mod, just go for it! The quality of the parts are top notch. Rick's excellent service and support is outstanding. If I can get this level of support and do the install all the way in Thailand, you guys in the US (and elsewhere) have no excuses not to do it
Chart
The first drive was nuts. The power combined with the shorter ratios completely transformed the car. The GT4 was already my favorite driver's car in my collection. Rick's mods took it to the next level.
The only issue we had was with the poor fuel quality of the pump gas here in Thailand. I started off running the car with race fuel. Now Rick and Autowerks are working on a new tune to run with the pump gas here. Once that's done I'll be back with more feedback.
If anyone is thinking about doing this mod, just go for it! The quality of the parts are top notch. Rick's excellent service and support is outstanding. If I can get this level of support and do the install all the way in Thailand, you guys in the US (and elsewhere) have no excuses not to do it
Chart
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08-04-2020, 06:10 PM
#5
Rennlist Member
A little wide-open throttle for your evening enjoyment
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08-21-2020, 04:01 PM
#7
Rennlist Member
Trending Topics
08-21-2020, 04:29 PM
#8
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08-21-2020, 04:42 PM
#9
Rennlist Member
Ah, so you were that GT4! I was chatting with Larry a couple weeks ago about bringing mine up for him to give a quick consultation on what he think he’d need to do to my car & he mentioned he had a GT4 coming in later that day. Small world, man!
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10-20-2020, 08:42 PM
#12
Three Wheelin'
Love the pics, thanks for posting! I'm glad to see the weather cleared up for a good shoot. It was great meeting you today Luca and seeing your new 4.5! Car looks great and of course I approve of your interior taste 
Hope you finish your engine break-in soon and get some time to enjoy the full revlimit before winter. I've been spending more time lately in other people's 4.5l cars than my own GT4 and boy 4l never felt so slow!
Hope you finish your engine break-in soon and get some time to enjoy the full revlimit before winter. I've been spending more time lately in other people's 4.5l cars than my own GT4 and boy 4l never felt so slow!
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Rick DeMan (10-23-2020)
10-20-2020, 08:54 PM
#13
Love the pics, thanks for posting! I'm glad to see the weather cleared up for a good shoot. It was great meeting you today Luca and seeing your new 4.5! Car looks great and of course I approve of your interior taste
Hope you finish your engine break-in soon and get some time to enjoy the full revlimit before winter. I've been spending more time lately in other people's 4.5l cars than my own GT4 and boy 4l never felt so slow!
Hope you finish your engine break-in soon and get some time to enjoy the full revlimit before winter. I've been spending more time lately in other people's 4.5l cars than my own GT4 and boy 4l never felt so slow!
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porscheflat6 (10-28-2020)
10-21-2020, 04:44 PM
#14
Three Wheelin'
FYI, for everyone else this is just a small set of 4.5L cars (excluding my car, I was just crashing the 4.5L party). For the folks wondering if the engines are reliable and make the numbers, there are a lot of 4.5L owners that can attest to the fact that they do. It's actually shocking how many 4.5L GT4/Spyders are out there that don't post on RL, almost like RL isn't the center of the universe or something, weird.....
Last edited by ajw45; 10-21-2020 at 04:46 PM.
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10-23-2020, 12:01 AM
#15
I'm a lurker more than a poster, but I'm also another satisfied 4.5L customer...
I recently took delivery of my 4.5L GT4 with the full set of DeMan gear ratios and upgraded diff. In prep for this decision I drove a buddy's GT4 and loved the mid engine chassis balance, but didn't necessarily love the transmission. The power was fine but paled in comparison to the 991.2 GT3 parked in my driveway. I was lucky enough to go for a ride in a 4.5L car at Rick's shop and after feeling that his approach addressed these shortcomings, I went all in.
Rick had been very generous with his time, both with a detailed tour and with explaining how he arrived at the package that exists today. The 4.5L car we were in actually didn't have the shortened gears and while tach ascent was rapid, it felt like we spent a little too much time in 2nd gear, whereas an earlier throw into 3rd would have been nice (but not really necessary). He also continues to test the package to find limits (e.g. cam-gear bolts) and there haven't been any material updates since the current 4.5L offering. I guess that's reassuring. I know from speaking with him that there have been options available to address idiosyncratic customer needs, but imho it probably does more sense to keep the menu simple b/c too much customization can get complicated down the road.
I opted for the GT3RS exhaust to maximize power. While it is definitely louder than stock, its fine at low loads and bearable at most other loads until you go full throttle- at which point the sound just feeds the experience. The sound just checks all the right boxes. Most importantly, the power is absolutely intoxicating (AA here I come!) and shift points are very intuitive. The later is important as the shorter gears give the flexibility to use the torque frequently, while also allowing for quick wind outs into the nether regions of the tach. With a heavy right foot, you just want to keep throwing into the next gear...the only thing better would be a no lift Drenth. Overall, the car is docile and well behaved while puttering around town (medium clutch weight with smooth engagement, smooth power delivery, rewarding sound feedback), and is eager to be unleashed when you feel its safe to drop the hammer (once the tires are warmed up). The break-in period has been a big tease, but I have a track day coming up and can't wait to open up the set-up.
Call me old school but my gripe with many new cars is that you have to drive them hard and at instant-jail-time-speeds to feel something visceral. Well, the 4.5L package enables that experience at legal speeds, but not at the expense of higher speed capability.
For those that are on the fence, I hate sounding like an advertisement as Rick doesn't offer sponsorships, but if any of these 4.5L ownership anecdotes sound interesting then you might consider giving Rick a call. This isn't his first rodeo and he's got the data to support the recommendations.
Oh, and in case you're wondering, the GT3 is long gone.
I recently took delivery of my 4.5L GT4 with the full set of DeMan gear ratios and upgraded diff. In prep for this decision I drove a buddy's GT4 and loved the mid engine chassis balance, but didn't necessarily love the transmission. The power was fine but paled in comparison to the 991.2 GT3 parked in my driveway. I was lucky enough to go for a ride in a 4.5L car at Rick's shop and after feeling that his approach addressed these shortcomings, I went all in.
Rick had been very generous with his time, both with a detailed tour and with explaining how he arrived at the package that exists today. The 4.5L car we were in actually didn't have the shortened gears and while tach ascent was rapid, it felt like we spent a little too much time in 2nd gear, whereas an earlier throw into 3rd would have been nice (but not really necessary). He also continues to test the package to find limits (e.g. cam-gear bolts) and there haven't been any material updates since the current 4.5L offering. I guess that's reassuring. I know from speaking with him that there have been options available to address idiosyncratic customer needs, but imho it probably does more sense to keep the menu simple b/c too much customization can get complicated down the road.
I opted for the GT3RS exhaust to maximize power. While it is definitely louder than stock, its fine at low loads and bearable at most other loads until you go full throttle- at which point the sound just feeds the experience. The sound just checks all the right boxes. Most importantly, the power is absolutely intoxicating (AA here I come!) and shift points are very intuitive. The later is important as the shorter gears give the flexibility to use the torque frequently, while also allowing for quick wind outs into the nether regions of the tach. With a heavy right foot, you just want to keep throwing into the next gear...the only thing better would be a no lift Drenth. Overall, the car is docile and well behaved while puttering around town (medium clutch weight with smooth engagement, smooth power delivery, rewarding sound feedback), and is eager to be unleashed when you feel its safe to drop the hammer (once the tires are warmed up). The break-in period has been a big tease, but I have a track day coming up and can't wait to open up the set-up.
Call me old school but my gripe with many new cars is that you have to drive them hard and at instant-jail-time-speeds to feel something visceral. Well, the 4.5L package enables that experience at legal speeds, but not at the expense of higher speed capability.
For those that are on the fence, I hate sounding like an advertisement as Rick doesn't offer sponsorships, but if any of these 4.5L ownership anecdotes sound interesting then you might consider giving Rick a call. This isn't his first rodeo and he's got the data to support the recommendations.
Oh, and in case you're wondering, the GT3 is long gone.
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