JDL turbo kit owners thread

[Steveiam]

I thought that's the power range where pump gas becomes prone to knock

[Amputechture]

You are right about that, I'm just speaking about that from a cost/benefit perspective. It would be much easier and cost effective to run ethanol and safely make power in the mid 300s. Beyond that, your next roadblock would be the strength of the factory connecting rods....or lack thereof. The cost of going flex fuel is roughly anywhere from 1K to 2K. The cost of building your motor is going to be waaaaay more than that, and lowering the compression ratio will cost you response. I would completely understand if you wanted to surpass 400 and do not have access to ethanol, but going through all of that and ending up making 334 or something on the rollers would not be an effective use of resources.

[James Russels]

Originally Posted by Amputechture

It would be much easier and cost effective to run ethanol and safely make power in the mid 300s.

Can you explain why ethanol would allow one to safely make power in the mid 300s whereas, I assume, achieving that power with higher boost isn't safe? In my mind, the rods have to be able to withstand that amount of power regardless of how you get there.

Also, and the reason I came to post in the first place, is because I am having trouble getting the bumper to fit after installing the kit. The weld on the bottom of the intercooler sticks down about 1 cm and is pressing on the black plastic tray lip thing that the bottom of the bumper attaches to, so I have to really stretch the bumper to get it on. This causes the bottom of the bumper to bow downward, and the grill pops out. Did anyone else have this issue, and if so, how did you fix it?

Pictures: https://imgur.com/a/xy1ZdsA

[OzzyGT86]

Originally Posted by James Russels

Can you explain why ethanol would allow one to safely make power in the mid 300s whereas, I assume, achieving that power with higher boost isn't safe? In my mind, the rods have to be able to withstand that amount of power regardless of how you get there.

Also, and the reason I came to post in the first place, is because I am having trouble getting the bumper to fit after installing the kit. The weld on the bottom of the intercooler sticks down about 1 cm and is pressing on the black plastic tray lip thing that the bottom of the bumper attaches to, so I have to really stretch the bumper to get it on. This causes the bottom of the bumper to bow downward, and the grill pops out. Did anyone else have this issue, and if so, how did you fix it?

Pictures: https://imgur.com/a/xy1ZdsA

IN MY OPINION, the reason for e85 being “safer” is the fact that it is more resistant to knock as opposed to 91-93. The fact that a stock FA20 has a compression ratio of 12.5:1 makes it paramount for you to be running a higher octane fuel especially on a forced induction set up. This is also the reason as to why on e85 you make much more power at the same PSI than on 91. You’re able to make more use of extra timing therefore making more power. So essentially you could be making mid 300s at give or take 8-10 psi on e85 while to achieve mid 300s on say 91 you’d have to be at 12-14 psi. As far as I know the rods are more sensitive to the amount of boost your running and less so to the amount of power you’re making. PLUS there are other properties that e85 offers that 91-93 does not like running much cooler due to its vaporizing of ethanol during combustion and etc. Hope that helps

[Amputechture]

^What he said. At a certain point though, it's not knock resistance and exhaust gas temperatures you are fighting...it's sheer stress on the rods. From speaking with different FI 86 owners over the past few years the 300whp neighborhood is the threshold for "safely" running pump gas/mid 300s is the threshold for "safely" running ethanol....and beyond that one needs to begin considering forged internals as the factory connecting rods don't care that there isn't detonation occuring, they are only physically capable of so much.

[gtengr]

Based on Cosworth's analysis that the rods are on the verge of their safe limit with their supercharger kits, I assume rod failure on this car is primarily a combination of force and number of cycles, combined with variance in buckling capacity of each individual's rods. E85 vs. 93 oct shouldn't really factor in.

[jRuN]

With that information, at what overall mileage on the motor should forced induction not be added without first rebuilding the engine with forged internals, strictly just due to mileage.






Sent from my Pixel XL using Tapatalk

[Amputechture]

Originally Posted by James Russels

Can you explain why ethanol would allow one to safely make power in the mid 300s whereas, I assume, achieving that power with higher boost isn't safe? In my mind, the rods have to be able to withstand that amount of power regardless of how you get there.

Also, and the reason I came to post in the first place, is because I am having trouble getting the bumper to fit after installing the kit. The weld on the bottom of the intercooler sticks down about 1 cm and is pressing on the black plastic tray lip thing that the bottom of the bumper attaches to, so I have to really stretch the bumper to get it on. This causes the bottom of the bumper to bow downward, and the grill pops out. Did anyone else have this issue, and if so, how did you fix it?

Pictures: https://imgur.com/a/xy1ZdsA

Wish I could help you there....I am not 100% certain as I have a version 1 kit. If you watch Ian Barton's installation video on YT, he ran into the same issue and found an alternative way to mount the intercooler to the radiator support bracket if I remember correctly. Maybe that will help you find a solution.

[Xero-Limit]

The "safe" HP level comes up very frequently in other threads too and I probably discuss this almost daily on the phone.

OEM like safe HP is 175. Not a single one more. Over the next 50k miles 98% of people will generally have no issues with bolt-ons/e85 at 200whp. 90% will not have any issues with a mild supercharged setup at around 260whp with 10% drag on the motor, so an effective 290whp as far as the motor is concerned had it been turbo without the belt drag. Most turbo setups will do around 300 whp at 10 psi. Many people have few issues there unless they are doing top speed runs or a multitude of 1/4 mile passes. Go above that and the chance / time to failure is a logarithmic curve.

I'd take e85 and 8 psi or e85 and 10 psi (but more conservative AFR/timing) any day of the week versus the same on pump gas (or more). When a knock/preignition/detonation event happens, the stress on the rods/pistons/bearings is 2-4 fold or more (will depend on the engine speed/load). So you are essentially putting 600 whp worth of stress on the rod during a knock event versus a regular power stroke. This is what kills most motors. Some fail from fatigue, push the motor at 300+ at the track with frequent high speed runs, it will suffer the same fate, just take longer.

So the safest path is 10 psi or less, use e85 if you can. If you plan on going past 12 psi on pump or e85, have the budget for a new motor. Doesn't mean you'll need to use it, but there is the possibility and nobody wants to part out a freshly built car.

[sroby]

Mike, that’s probably one of the best understandable, logical explanations in common sense that I have heard explained in a long long time. If a human being can’t understand this simplification, they really need to be driving a 2004 crown Vic with mustang Gt wheels, and call it a day. Outstanding my man. ❤️��

[Rekzer]

I'm thinking of buying the uel jdl v2 turbo kit and I already have the open flash tablet as I'm running full exhaust stage 2+ tune. Is there a base tune I can load onto my brz using the open flash tablet and then drive my car to a tuner. Also could the tuner tune it thru the oft??

[Amputechture]

Swapped the old JB precision 4854 for a disco this past weekend. Man oh man, what an incredible improvement in response and low end power. For deliberating opting for a BB it is worth every penny and then some. The difference in transient response is night & day. I was hesitant on going for the 2860 rather than a 2871...and ended up going with a 2860 with larger .82 housing to help with any high rpm drop off.

https://ibb.co/PQ3Pppy
https://ibb.co/0nsmX0b
https://ibb.co/C790TT8

[Joveen]

Originally Posted by Rekzer

I'm thinking of buying the uel jdl v2 turbo kit and I already have the open flash tablet as I'm running full exhaust stage 2+ tune. Is there a base tune I can load onto my brz using the open flash tablet and then drive my car to a tuner. Also could the tuner tune it thru the oft??

I doubt it. You can get a base map from shiv and have him etune it but that takes weeks. Just get Ecutek which much better for tuning.

Sent from my SM-N960U using Tapatalk

[DarkPira7e]

Originally Posted by Rekzer

I'm thinking of buying the uel jdl v2 turbo kit and I already have the open flash tablet as I'm running full exhaust stage 2+ tune. Is there a base tune I can load onto my brz using the open flash tablet and then drive my car to a tuner. Also could the tuner tune it thru the oft??

It's not ideal, but a tune for a turbo car is definitely doable through the OpenFlash Tablet. A lot of people run a simple turbo build using Shiv's remote tunes. I definitely think an ECUTEK tune would be much better, because there are a lot more options available through it.

When I put my turbo on my car, I drove it on the car's OEM basemap for a few days. If you stay with OEM injectors and fuel pump until you get the tune, honestly it'll drive fine out of boost. If you drive this way, also leave the stock MAP sensor plugged in. Just don't hit boost. Don't. And don't expect it to run perfectly. Still monitor LTFT, AF/R, knock correction, etc. because if there's an exhaust leak at the header flange it'll cause your AF/r to be way off and give high high LTFT.