Ethanol on an NA engine - Dyno tested
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Test engine spec:
Modified smallport head w/ oversized valves
kelford beehive valve springs
shimless buckets
oversize toda pistons (1627cc)
bc rods
approx 12.5:1 compression
arp hardware throughout
toda oil pump gears
toda 3.7kg flywheel
52mm itb's
Garage4age Header and 3" exhaust
Link g4 ecu
Kelford 300 deg camshafts + VVTi
E100
E85
E50
E30 - ยานยนต์และพาหนะ
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Lots of comments saying the engine needs more compression to see more gains. As I said in the video most people know there is a benefit when the engine is knock limited. So of course raising the compression until the engine is knock limited on 95 ron. There will be a bigger benefit from ethanol due to the higher octane of ethanol. Its the same situation on a forced induction engine. The test was to show the other property's of the fuel, not just the octane rating. Ethanol isn't easy or cheap to get here, so this engine will be staying on 95
95+meth is the way to go for a streetable daily when you need to exceed the knock threshold of the fuel you have at the pump (certainly the case here inthe uk) I was knock limited to 19psi on a stock rover 1400cc k-series bottom end (about 240hp) but a bit of water meth and i could roll 30+psi through her and make mid 300hp. from what I gather E85 would have the same effect, but you cant get it at the pump here.
Same in Aus, ethanol is not very common except E10 which is basically RON95. So many people on net doing dyno runs on E85 claiming big power. I think Motive did it with the GR Yaris and told me that you can have barrels delivered to your house, hardly accessible. Thanks for the video.
@@chippyjohn1 Yeah, e10 98 was available in my area till about a month ago. which was 95 with 10% ethanol. now best can get from the pump is 95ron. Flex fuel seems like the way to go for a knock limited setup. Once all setup and tuned right, just dump some e85/e100 in the tank when want to go fast. when run out still can drive your car
@@Garage4age In the US we use AKI for some reason which is (RON+MON)/2 so our regular is 87(90RON) and our premium is 91 or sometimes 93(95/97RON). Where I am almost all fuel has at least e10 if not e15, but the octane is figured after the ethanol is added. There are some stations without ethanol in the premium which is better in small carbed engines. And e85 is very common, I'd say at least 25% of stations have it. Sometimes stations will have weird blends like e30 for some reason. We're in a big corn producing area so our e85 is super cheap, about half the price of regular low octane.
Dyno nitro methane
Very interesting. Rare to see such comparisons on an NA engine
You are so generous with pulls I love it.
Others make 10 minute video from one pull.
I've gotten pretty much the exact same results as you did between 95 & E85, (our 95 at the time of the test had 10% ethanol added to it). ~5whp at peak power.
I also tested 98 and for some strange reason I got more power from that compared to 95, the 98 had 5% ethanol mixed in, I find it strange that the higher octane gave more power than the lower octane with 0 change in tune. Would be very nice If you could replicate the results, with a lot better NA motor than I tested with.
Great video as usual :) Thanks for all the work you are putting i, I know it takes a lot of time and money.
Not that strange, unless you have direct injection the fuel takes up space that could be used for more air. E10 requires more fuel to be mixed in then E5 or straigth gasoline.. It's a small difference but it's there.
Yes e10 has less calories per grams compared to e5
Hi mate, Im from Brazil and we have E100 on pump gas since 70's here , to get real good bennefits from Ethanol u must run a engine with 12:1 to 14:1 compression rate (sea level) for real good gains especialy on low and mid revs torque
And u should use more cold degreas spark plugs like 6 or 7
And the engine showld work with more temperature around 92 to 98 Celsius
15:1 was commonly used in racing engines with E100.
Yeah, some 100% ethanol engines came 13~14:1 from factory
And yes, default tuning is advance spark timing, change plugs, change thermostat, correct afr
Brazilian Power
Love the intro that 4ag ITB sound track 🤌🏼
We've been seeing absolutely massive gains running E85 on multiple NA E36 BMW's. Feels like the car gained an extra cylinder on every single one we tried.
I've been wanting someone to do this test for a long time, 5hp is nothing to sneeze at for just changing fuel.
While it's decent gains for a NA, you can't buy it from the pump here in NZ so it's rather expensive
@@NEOVVL. Yeah it's only worth it if your area has it
With the same CR off Gasoline Yes, try that with 13.5:1 CR and see the miracle happens
Not really considering the massive difference in km per litre.
Unless you were getting the ethanol cheap or something.
Not worth it for 5hp
Club racing car and economy ? C'mon guys
Man your videos are always so interesting... but the work of answering so many comments and discussions afterwards is at least as commendable!
Great video. That 4A in your KP is a real champ to be constantly flogged like that. SAE paper 2010-01-0619 Investigation of Knock Limited Compression Ratio of Ethanol Gasoline Blends tests compression ratios from 9.2 to 13.66 and E10 to E85 blends. Very interesting read for the nerds among us.
like some sweds they machine 3mm or more of their engine heads on the old B230's and run pump E85 the ability to increase compression without knock is where the biggest gains lay
Awesome info as always boet, thanks for Dyno results on different fuel
I used E100 for quite some time in race engines. You can extract a lot more power in a NA engine with ethanol, but to do so you need a higher compression ratio. 20 years ago, when just a few gasoline engine were using 11:1 or higher, you could use 15:1 with ethanol very easily. And the power gains were outstanding.
decent gains with something like 12.7-13:1 Cr on ethanol?
Finally a proper test on this, thanks 🥰
Your videos are perfect.Straight to the point. I think you can get more power with the higher octane fuels by advancing more after 9200rpm.
Been considering making the switch myself. This is exactly the kinda video I was looking for. Thanks!
atleast e85 is a bit cheaper than gas in some locations. Do like a 80% 91/93 gas and 20% ethanol blend. For Na that should be more than enough Knock mitigation.
This is one of my favourite channels, no BS no theories just straight up testing and results. Keep it up man!
Great videos man! Thanks!
Ethanol is magical. Been using e100 for years in a high comp engine
Great video as usual
Very cool test, results are spot on with what I was told by my guru, gotta run way higher comp to get anything more out of it, at that point you have to get fuel in by the barrel load and you're looking at a 20hr engine unless you invest in Titanium internals (re: the white/yellow hillclimb Starlet).
12.5:1'ish on good pump gas simply seems to be where built 4A-GE's are happiest, anything more than that you're better off with a different engine all together (even the white/yellow hillclimb Starlet guy went over to a V8).
Yep, and people seem to think going from 12.5:1 to 13 or 14 is going to add lots of power, but isnt going to be any big gains there. Compression that high in a 4a, start to end up with an ugly shape combustion chamber that promotes knock due to the shape of the pistons. The hillclimb starlet was super cool. but imo, he could have built something that made the same power, with less revs and be more reliable/ less maintenance.
I've done a thesis on blend of ethanol on a 4age. If you start to increase compression, you start to see the real gains, without any knock
Lol 😂
Love the content bro
in smaller engines the cooling of ethanol is quite nice when you are constantly at high rpm and especially at slower speeds :3
It may not be much of a peak HP jump, but the overall improvement below the curve is actually great. Ethanol seems to help a lot of engines gain torque and peak earlier in the powerband, which isn't a bad thing.
Always fascinating, always testing different ideas 👍🏻🍻
E85 is half the price of 98 where I live. Glad I made sure the fuel system was compatible when I EFI'd the motor!
Where do you live?
@@adrianzmajla4844 France. 4th biggest producer of E85 world wide.
Sur quel moteur ? @@dra911
J'ai regardé ta chaîne, pas mal la porsche gros boulot.
J'ai même vu du e85 à 77cts contre quasi 1.80 le SP98 pas loin de chez moi. Mais globalement, c'est moitié moins cher, oui
Every hp Count wen the Engine is on Limit..Great video ✊
I saw a science paper which found adding 1%water to ethanol blend helped somewhat also.
100ron and 2-3 degrees advance is the best both for power and for safety from unexpected detonation
Very informative, thanks!
Great work
Best opening 10sec ever!
higher dynamic compression may show even more gains with ethanol
Great video! I especially love the doort-meter. Can this be a regular feature in the trumpet design vids 😊
NA tuning is all about stacking the 3-4hp gains one on top of another and all of a sudden you’re making 10-15% more power than you should
maybe the next trumpet video can be a dort off, who can make the loudest trumpets haha.
@@Garage4age I read a musical trumpet thread that concluded that oval shaped orifices can make more noise than circular!?? Might be something to that or a massive yarn. Who knows?
Good to know what to expect when I'm setting up my flex fuel.
This is amazing, I would love to see see the comparison between Avgas, pump fuel and ethanol.
This is very similar to the results I found as well many years ago, except in my case there was a slight loss in power with E85 despite adjusting the ignition on the dyno for best torque.
I believe this is due to the lost effective displacement from having to run it 50.5% richer to get correct AFRs and there was no gain to offset this slight loss due to most likely the lower CR of 8.5.
The only time high E blends worked well on NA was on engine builds where we built the engine from get go to run E85 with 14:1 CR.
Nice to see(and hear) a 4AGE in its natural habitat 0.04.
I’ve seen the comments about high compression. But I’m going to try this on my 4AFE with a 9:5:1 compression ratio. I’ll port the head too, even lowering the CR further. And I’ll use PerfExpert app as I don’t have a dyno to measure results. As always thanks for sharing your findings bro
Raise the compression!
we did (~2 points) in fsae with a zx6r powered go kart, though that was also influenced by a restrictor plate on the intake.
You are the MAN! Did u measured differences on the road in terms of acceleration?
More outside video of the starlet 🙏 the Sound is fab
Would have been good to see NPD 100 as well. On a side note, in boosted cars, we have seen good results from only 10% ethanol with the flex fuel setup. It seems having any ethanol in the system can reduce knock dramatically.
Great and useful info.
I would really like to see you test plenum volumes. There's very little information or testing out there.
In Brazil do not exist pure Gasoline . Gasoline in Brazil has 27,5% etanol.
Do all of your modern Chevy products etc have provision for E30 blend?
Modern Chevys here are all flexfuel, they can run any % or mix of alcohol in the gasoline... Only problem is that our gas is almost never pure/always mixed with solvents or else...@@Christdeliverme
@@Christdeliverme my 1995 Ford möndeo , Zetec 2.0 runs ok whit OEM ecu. In Brazil flexfuel cars is standart since 2005.
Yes, we dont have 100% pure Gasoline in gás station
What were the AFR on 95 and E85 ?
You mention that you corrected it,but what are they ?
12.5 - 13 afr on all runs, on the gasoline scale. 85-88 lambda. I checked if it liked richer or leaner on the ethanol before recording the video.
@@Garage4age Ok,thanks.
Thx for the Ethanol testing.
I use E85 in my 323f with Z5 engine. I portet the Head and at the Dyno it get from Stock 88hp to 96hp and wonder how much the Ethanol help to get the +8hp
How big were the air mass flow changes when switching between fuels? (can estimate this from the required fuel change to reach same lambda)
3% is in-line with all the NA ethanol data I've seen. Unless compression is insane, it only benefits from the oxygenated content (liquid o2). 8-11% is what turbo/SC engines typically get. I've seen 40% make the same as C16 with an blown LSX.
As for octane, effective octane skyrockets from 0-30%, then flattens off where 40% to 100% only gains a few more points. This is largely from the charge cooling effect, and why it helps so much more with boost.
Good to see you again. Could the gains be bigger in hot weather?
Gains will be considered bigger with a higher compression ratio.
Another great vid! Who would have thought a little additional charge cooling and some extra oxygen would give more output..... Shows also just how spot on your tune really is! Time to up the comp? (Your second E50 run during the run was shown as being an E85 run btw.)
So it is, must have dropped the wrong text in there. Too much of a pain and expensive to get ethanol here considering the extra it uses. so will be sticking to the current compression ratio and 95
I thought it sounded good on the dyno! Sounds even better on a road pull!
E85 or more needs an afr of 7-9:1 and much higher advance to get optimal resultuts
If not octane / knock limited, ethanol actually needs less timing to get to mbt than gasoline/petrol. so just tipping it in the tank is like advancing the timing a bit
If you add a bit of “top-lube,” the common upper cylinder lubricant that’s used in methanol powered race cars to limit corrosion / friction, I’d bet it would pick up a little bit more from just the ring / valve seal improvement and slight friction reduction.
Thats completly bullshit
Now try toluene ahaha.
What interests me is the change in the shape of the curve. Especially right at the top. The more pump gas in the mix the more it has the defined dip and spike at the top wheras with Ethanol it smooths out.
Pretty sure that's just a coincidence at the top end. Dyno does weird stuff on this car at the end of the run. its pushing the speed limit on dyno and engine is setup to to go into the limiter softly, not hard cut. so depends which way the stars align, sometimes it does a dip at the end sometimes a spike. I would ignore anything past 9500rpm. it doesn't do it if run it up in a lower gear. but all my testing is based on 4th gear runs, so 4th it is
Looks like higher peak hp with 95 but quite a bit more area under the curve with the higher ethanol blends?
Hey are you gonna test david vizard theory on unequal headers length.. that he supported with data and has more hp over the whole dyno curve ?
What is the AFR for your engine for max power on 100% petrol and 100% ethanol? Do you need to tune your fuel maps?
Have you done runs comparing NZ 95 and 98?
I think each test run at iso richness. With ethanol you can hope gain at richness 1.2 instead of 1.12 for gasoline.
i would be very interested to see you test tri-pak octane booster (or similar) using 95 octane and boosting it to 99 and trying more timing with it
What's the point? The engine is at MBT now and would probably lose power with much more advance.
@garage4age Could you do water methanol vs. E85? Theres a big debate on which is better, people like me forexample swear its better than even E85 when it comes to knock resistance AND power . Would love to see that!
One more thing. I think it has a good potential for improvement if you’d rise the cr.
Id be interested to see what you did with injectors and duty cycles.
And it would be interesting to see an ethanol test on big compression
It was just a % change in the fuel map, so easy to get pretty close. from memory the e100 needed about 40% more fuel. lower blends obviously less. engine has 980cc injectors so plenty of headroom
Maybe try with higher compression?
I like ethanol and liked mixing E85 to get to E20. This worked best in various cars without any changes. Unfortunately, there have hardly been any E85 in Germany since 2016 for political reasons. Our state tyrannizes us wherever possible and restricts us from many beautiful things. Ethanol is a great way to bring coked-up and rough-running engines back to life. I work in an independent workshop and used to do a lot of repairs until 2016. Problems that arise from the EGR and oil carbon can be cleaned again
Hi! As always, great video!!!! Bravo!!!
May I ask what ecu you use for tuning?
link g4
@@Garage4age awesome! I always use Link too 🔥🔥🔥
How about a test, rec fuel with no ethanol vs 87, 89 and 93 with its percentage of ethanol.
I was surprised, the 93 with ethanol made more power on my higher compression 2 stroke.
I got the same results with nikos motor, there wasn't enough in it to warrant running e85, it's more of a hassle to acquire compared to pump 98 where you can purchase that everywhere in AUS
Yeah, Is even worse here, cant get E anything from the pump anymore. Maybe if it was worth 10-15hp, would consider going flex fuel. Good to hear results were the same
Nitro blend next?
Excellent as usual - cheers. How do the prices per litre compare across those fuel types and mixes?
Here its bad, Can only get ethanol in containers. E100 is about 30% to cost wise and need about 40% more volume wise to get to the correct fuel ratio. so yeah would cost over double to run. safe to say im not going for that power gain
Does your 95 Ron have 10% ethanol in it? Grass roots motorsports tested a Miata on straight 93 octane and e10 93 made more power.
no ethanol in the 95. I used to run pump e10 98 but they stopped selling it. judging by the the trend i've probably lost a kw or so on 95ron.
If I recall standoff injection was a difficult one to test, so it's understandable if yo would prefer not to revisit. It would be interesting though to see if giving the ethanol more room to cool the charge would give any additional gains.
If i get keen one day, will try it
This is somthing im keen to see
i currently have a 4age 16v with 20v rotating assembly and other modded internals,std cams but the head is ported and pollished,what to you suggest i do next? its a street car and no means a track car, do your suggest a rev kit?
just looking to gain knowledge
Ask someone to flow test the head, and recommend cams based on the flow test results. If they can't or won't recommend cams, they don't know what they're doing and shouldn't be doing performance head work.
E100 likes higher compression ratio. From 12:1 to 14:1 and more advanced ignition timing than gasoline.
Ethanol actually requires less advance that gasoline. It can tolerate more compression yes, due to the higher octane rating. Engine in video is 12.5:1
Biggest problem we have when converting to E85 is injectors not giving enough fuel at higher RPMs. Don't know if it happened here.
Has 980cc injectors. so no issue feeding it enough fuel
Needs a few points of compression.
Can you try methanol injection on this motor with pump gas or e85? Maybe you can borrow a methanol setup.
I can confirm this on Renault F4R engine (2.0L 16V). Engine with standalone MaxxECU and tuned for both Pb98 (E10, our comercial fueal) and E50. There was no difference, or was so small (dyno tolerance) so this is totally economically non sense.
50 /50 methanol 💦🏁🚀🚀🚀🚀🚀 ron98 shell
Is there a build series on this engine specs?
basic spec list in description
Ethanol to yield its maximum, needs about 3 points more compression ratio
not a lot of advantage running alky in this engine. have to run advance because alky is hard to start and slower burning. the real benefit of alky is being able to run much higher compression ratios
and pick up the HP
Diesel has a higher energy density, so it would be great to see different diesel-ethanol blends on the dyno! 😄👌
F1 did use a bit of diesel along with benzene and toluene back ib the 80s
Diesel also has an octane rating of 0, so you will knock at like 5:1 compression on 100% diesel (also you have to pre-heat it so it will vapourise). Ethanol has a blending octane of 120, so 50/50 ethanol/diesel should have an octane of like 60.
Fun facts, the Swedes used to run diesel buses on ethanol. It's hard to imagine a worse diesel fuel, they had to add lots of cetane booster (5% of the fuel was cetane boosting additive) and run a compression ratio of 28:1, along with a special exhaust catalyst to get rid of the aldehyde smell. Apparently the exhaust emissions were pretty good otherwise.
are you using stock crank ? or dry sump ? i have a built 4age ( rods pistons with balanced bottom end etc ) with 300cams and i am afrid to go beyond 8100 rpm, are those rpm reliable ?
stock crank and sump. just some minor oiling mods. not expecting it to last forever at 10k. but they will do 9k all day, even stock bottom end is fine in the low 8000's
@@Garage4age thanks for the kind reply, guess i will crank it up a bit more then :)
182 kw 🚀🚀
Does that mean in regular car that accept E85 you won't notice difference in performance?
assume you mean flex fuel car. it really depends on how its setup. if the engine is knock limited on normal petrol/gasoline. you will likely find the ecu will change the tune to take advantage of extra octane rating in the e85 and make more power. my engine isnt knock limited on either fuel. so is only small gains
Would be interesting to use an O2 bottle, just bring up the oxygen content to maybe 25% and see how much power it makes, either that or nitrous with the ethanol. Using the ethanol nitrous as a cobined shot might be an option for fun. Or go hybrid, install an electric motor to smooth out the powerband.
Liquid oxygen injection was tried on aircraft during WW2, to get more power at high altitude. It sure boosts power, but unfortunately it also has the effect of making the combustion temperatures insanely high leading to burnt pistons and exhaust valves.
Nitrous is much more tolerable in that regard.
@@nerd1000ify That is why it would be good with methanol as methanol reduces temperatures significantly.
My most liked channel. I would be happy if you could give me some hints for ignition map and afr a VW, 2,0l, 8V, 11,4:1, 272°.
I have no knock sensor ....
Currently I run only 28 degree advance above 5000.
Thanks for your videos!
Hey, cant really suggest anything for ignition map, every engine likes something a bit different, but 28 degrees sounds ballpark. afr wise, most engines will make basically the same power over a pretty wide range. I have a video showing this if you havent seen it already. 12.5 - 13afr fine for most na stuff
Always love your no nonsense videos. Be interesting to see water meth injection, to cool the intake down and see what difference it makes to a NA engine.
Could a test be done with the 100% ethanol with maybe less timing as it burns quicker?
Gains probably wouldn't be drastic but just an idea
Yeah it was probably a touch over timed on the ethanol runs. hence power staying the same with timing change. other than the 2nd e100 run, which im 99% sure was the dyno or engine spitting out a bit more power for what ever reason that run, rather than the igntion change. 95ron was probably a touch under timed hence why it made a little more at the end.
I would like to know why the E100 fell off at 9600rpms, unlike every other blend that seemed to soar due to, what I imagine, is the intake pulse boost.
its just the dyno having moment up there. Its getting a bit fast for it speed wise and the car starts going into the limiter at about 9800 so does weird stuff. ignore above 9500,.
Alcohol makes more torque down low because it displaces more air in ports, making them act smaller, thats why peak power rpm drops also.
You need a higher CR to get the max gains
So In conclusion more octane and the old dizzy twist makes all the difference?
all the dizzy wind
Well very little actually....
Seems.like the injectors are topping out on E100 in the top end. How much of a difference is there in air fuel ratio between e100 and ron95?
Has plenty of injector. 980cc 40% dc on the 95 , over 60% on the e100. Can't remember the exact numbers. 12.5 to 13 afr in the gasoline scale on both. Checked different ratios before made video. Ignore the bump at the end of graph, it's not a thing
@@Garage4age 980.. WOW, yeah that should be enough. I've never used pure ethanol, but shouldn't that be run at 11:1 afr or higher? The bump is present on both ron95 runs, how come?
@@hectorae86 just a coincidence, the dyno does it on this this car as its maxing out the dyno speed and the way engine goes into rev limiter, sometimes it dips sometimes it spikes, just ignore after 9500rpm. If i re scaled the wideband to ethanol scale, that same 12.5 afr would be 7.6afr when on e100. or lambda .85
@@Garage4age dude, you truly are a well respected source of valuable information and I applaud you giving it away for free.
Air fuel ration for gasoline is 14.7;
Air fuel ration for ethanol is 9.1;
Air fuel ration for methanol is 6.47;
Did you add fuel when measuring with ethanol?
Yeah afr was correct for each fuel. Before making the video, I even tested to see how rich or lean could go with the ethanol before loosing power on this engine. All those numbers are just same in lambda
finally a video on this. This is a concern for my stock 3sge Beams Redtop motor. Here in california we only have 91 octane (95Ron other countries) I think im better off just getting a VP race fuels octane booster when I get my Link MonsoonX ECU.
stock compression beams will be fine on 95ron/91 usa
@@Garage4age well to my understanding. Beams is tuned on 100ron (93 or 94 octane) from toyota
@@justintowers8230 you'll get to best power on 95ron. unless is really carbon'd up. from memory they are only 11.5:1 compression
@@Garage4age 11.5 compression is for 2zz and altezza. Mine is 11.1 compression on the redtop from the Celica SS3 and MR2
I’m a bit surprised you can run MBT spark everywhere on 95. Have you done MBT/DBL spark loops during your tuning?
Unsure what you mean by "DBL spark loops"? Assuming you mean advance the timing to best power, then remove timing to confirm? if so yes, and i always tune with a headset listening for knock.
@@Garage4age Yeah, basically that, keep advancing until you over advance and lose power to find Maximum Brake Torque (MBT) timing, if you hit knock before you start losing power you have reached Detonation Borderline (DBL) timing and probably haven’t reach MBT so you’re detonation limited. MBT timing is pretty much only affected by combustion speed, whereas DBL timing is affected by air charge temperature (ACT), combustion chamber temperature, fuel octane rating and some other things. You can be at MBT at one ACT and if it goes up then it can put you into detonation. At peak torque, where the cylinder fill is best, it’s unlikely that you can run MBT timing. When I was a powertrain calibrator for an OEM we had seperate tables for MBT and DBL, with modifiers for both. The control strategy picked the least advanced of the two. At peak torque when the volumetric efficiency was over 110% it was heavily detonation limited, but as the volumetric efficiency dropped off at peak power it wasn’t detonation limited. Yours will be different as it looks like you’ve designed your intake to be very efficient at peak power. So long as you’re not under-fuelling, getting the spark right is more important than fuelling.
Where did you pull the acronym DBL from?
@@jzab Yeah i've been tuning stuff for over 15 years, just hadn't heard or knew what the abbreviation / acronym DBL meant. I was assuming you meant "minimum best timing" by MBT. The only time i would over advance an engine, is to see how much of a safety buffer before engine runs into knock. Not much point over advancing till lose power, which can be a lot more advance in some cases.
Working at an OEM. Some engineers call it BDL (borderline detonation limit) some other call it DBL (detonation borderline). Either way it's the spark timing where the engine just starts to detonate. It's good to know when tuning because even it is more advanced than maximum brake torque timing (MBT), you need to know how close your running to it. BDL timing changes a fair bit with engine temperature, intake air temperature, AFR and other things whereas MBT timing doesn't move much, therefore if you tune at one engine condition and everything is all right, it may get pushed into detonation if engine conditions move away from where you've tuned.
what is the injector size on the engine?
bosch 980cc