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420A Need help getting more power out of the 420a and before anyone says turbo, spray, or swap it, i cant. Rules for my class dont allow any of those.

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does it have to stay a 2.0? if not you could swap in an EDZ block which is 2.4L.
other than that
-- high compression pistons
-- head work (p&p)
-- cam

actually first is should ask what do you already have done.
are you looking to gain on the high end?
 
Right now the engine is bone stock. I have removed everything but the alternator to free up some power. Highest gear I hit on this track is 3rd. Just looking at ideas right now and weighing options. Thought of doing a swap but it would have to be another n/a 2.0 or 2.4 that would pass for "stock". Rules say engine must remain stock but the Honda guys here are running k series engines in integral and techs don't say a word. I've already gone full retard on the suspension just need more hp at this point
 
here is the mod list for BulletDSM's car when he ran 13.231 @ 106.09 mph
Current mod list for the car:


Trans Modifications

Quaife LSD
NON modular clutch set-up; Audi PP, T4 Dodge disc, Neon Flywheel
Polyuerathane motor mounts (sides)
solid roll stop (front) Energy suspension filled with pl-400 (rear)


Engine Modifications
JE 12.1CR pistons
Crower 3 cams
Stainless valves
.020 off head
5 angle valve job
AMM port and polish (intake and exhaust)
MLS Head gasket
Of course, full rebuild on bearing etc. (stock)
PT Cruiser lifters and rockers
Eagle rods


Outside:
AF/X pulley
MSnS
Mustang 450cc injectors
Mustang 65 mm TB
AMM Intake
AEM adj. cam gears
Mark Peachy air horn intake
Catch can
Mark Peachy LTH
2.5 modified downpipe back exhaust
No power steering /AC
Honda “race” radiator
Snowmobile battery
Summit heat wrap


Chassis Modification
Teins and ad.j KYB’s (1.8 drop) in front
Stock springs adj. KYB in back
Upper strut bar


Interior Modifications
Remove passenger air bag; replace with modified sheetmetal gauge panel
Remove rear seat
Remove passenger seat
Remove carpet
Gut door


Exterior Modifications
Remove wing
Lexan rear window
Carbon fiber hood
Fiberglass hatch



he put down 219.4whp, max tq 175.0. on the dyno. i don't think its with that exact mod list, i believe the dyno was later on and he was running something like 16:1 pistons but i could be wrong.

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i hate to say it but if your going up against k-series engines, your at a disadvantage. a k20a2 with an intake, exhaust and header + a good kpro (hondata) tune will put down numbers like on BulletDSM's dyno.
on top of that the kseries has vtec and vtc. the vtec cams have a set of lobes optimized for the low - mid range and lobes optimized for the high end.
the vtc allows you to optimize valve overlap thru the whole rpm range.

the 420a has none of that

--
 
I take it nitrous is out? I mean that would be so easy, you wouldn't have posed the question. How about water injection and raising the compression ratio? The water suppresses detonation induced by the higher compression.
You might be well served to see what a more N/A oriented group would suggest (not that DSM folk don't want to help, but far more talk of turbos here). The SBC is the basis for all kinds of racing class engines in all kinds of racing (drag, circle, boats...) and those folks have likely looked at so many options on squeezing another 1 or 2% to be competitive. Just to be clear, I'm more of a Mopar guy, so don't pepper me with SBC-bandwagon jeers. But it IS the standard out there.

I just notice your "no spray" reference, so sorry to retread that idea.
 
I just notice your "no spray" reference, so sorry to retread that idea.

here is the mod list for BulletDSM's car when he ran 13.231 @ 106.09 mph
Current mod list for the car:


Trans Modifications

Quaife LSD
NON modular clutch set-up; Audi PP, T4 Dodge disc, Neon Flywheel
Polyuerathane motor mounts (sides)
solid roll stop (front) Energy suspension filled with pl-400 (rear)


Engine Modifications
JE 12.1CR pistons
Crower 3 cams
Stainless valves
.020 off head
5 angle valve job
AMM port and polish (intake and exhaust)
MLS Head gasket
Of course, full rebuild on bearing etc. (stock)
PT Cruiser lifters and rockers
Eagle rods


Outside:
AF/X pulley
MSnS
Mustang 450cc injectors
Mustang 65 mm TB
AMM Intake
AEM adj. cam gears
Mark Peachy air horn intake
Catch can
Mark Peachy LTH
2.5 modified downpipe back exhaust
No power steering /AC
Honda “race” radiator
Snowmobile battery
Summit heat wrap


Chassis Modification
Teins and ad.j KYB’s (1.8 drop) in front
Stock springs adj. KYB in back
Upper strut bar


Interior Modifications
Remove passenger air bag; replace with modified sheetmetal gauge panel
Remove rear seat
Remove passenger seat
Remove carpet
Gut door


Exterior Modifications
Remove wing
Lexan rear window
Carbon fiber hood
Fiberglass hatch



he put down 219.4whp, max tq 175.0. on the dyno. i don't think its with that exact mod list, i believe the dyno was later on and he was running something like 16:1 pistons but i could be wrong.

You must be logged in to view this image or video.



i hate to say it but if your going up against k-series engines, your at a disadvantage. a k20a2 with an intake, exhaust and header + a good kpro (hondata) tune will put down numbers like on BulletDSM's dyno.
on top of that the kseries has vtec and vtc. the vtec cams have a set of lobes optimized for the low - mid range and lobes optimized for the high end.
the vtc allows you to optimize valve overlap thru the whole rpm range.

the 420a has none of that

--
Some of that I can use but I can only get away with so much. Not trying to get the nascar inspectors breathing down my neck. I've got my weight down to about 2300 which is about as low as I can go. With the new suspension setup I should be able to out corner the Hondas but they have me in the straight. If I can get near the 170hp range I think I can fight them off.
 
look into the edz swap, its possible the block is just taller than the 420a's and wouldn't be noticeable if you swapped it

you could also try and shave off some weight from your rotating assembly.
like knife edge the crank, lightweight flywheel,
lightweight rods if you could find some, but i haven't ever seen any
 
Hey, look into the rev limiters. I have a Bee-R setup that I only paid around $85 for that allows me to rev to 8500 rpm. Obviously you can't just slap it on a stock car. You need some good rods to prevent snapping, some heavier springs to prevent the valves from floating, and a test pipe to prevent the cat from burning up. But it's worth it to be able to stretch each gear out farther.
 
How is it k series swaps are allowed? I mean maybe a b series looks stock in a honda bay.
they probably are running car like the ep3 (2002-05 civic SI snatchback) and RSX.
they both come with k series engines. the base RSX and the ep3 have the crappy k20a3 but you can swap in a k20a2 , use the a3 water pump housing, and ditch the oil cooler. then the only way to tell its an a2 without pulling the valve cover is the stamp on the block.
A k24 block is 19mm taller but if you bolt a (k20a2/z1) head to it and drop it in, the stamp on the block is the only tech would know the difference.

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What size track are you running? You need to be able to run the car in 2nd instead of 3rd unless you are on a 1/2 mile your probably hitting 5500rpm going into the corners in 3rd i'd guess?

If you want to do the 2.4 swap like dustyboner said then you can run 3rd since 5500 is the upper end of the 2.4's power band so if your looking into that disregard any further info below

To get the car so you can run it in 2nd you'll want to swap to a manual neon transmission instead of the eclipse one. Find one from a 2g neon that has 3.50 final drive gears instead of 3.94 gears. Then also get modern performance PCM. They list them for neons but they also work with eclipses. You can get the rev limiter raised to 8000 rpm. You have to change your rod bearings once or twice a season depedning on how much you race but it's easy enough to do that. I would also highly recommend using ARP rod bolts.

Circle track racing isn't all about horsepower. A lot of it has to do with gearing. I can run my Stock 1993 132 hp N/A 4g63 Eclipse in circles around any cavilaer and most hondas because the gear ratio is just perfect on them and they stay in the powerband. I'm sure you feel the car lug before it takes off coming out of the corners running 3rd because your dropping out of the cars powerband. If your still struggling with keeping up after getting the gearing right then you may want to start building the engine. Put a jeep throttle body on it and bore the intake manifold to match, then add cams, 18 grinds will get you power without a lumpy idle, then if your still struggling build a higher compression bottom end. Building the bottom end is the most expensive to do which is why I listed it last but it will also be the most effective especially couple with bigger cams.

NIce car by the way. I've got a clapped out 2g I race occasionally that's got the 2.4 swap in it. If I could do it all over again I would stick with the 2.0. I was just trying to go the cheap route and it makes a competitive car but I think a built 2.0 would be faster.
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look into the edz swap, its possible the block is just taller than the 420a's and wouldn't be noticeable if you swapped it

you could also try and shave off some weight from your rotating assembly.
like knife edge the crank, lightweight flywheel,
lightweight rods if you could find some, but i haven't ever seen any

Hey, look into the rev limiters. I have a Bee-R setup that I only paid around $85 for that allows me to rev to 8500 rpm. Obviously you can't just slap it on a stock car. You need some good rods to prevent snapping, some heavier springs to prevent the valves from floating, and a test pipe to prevent the cat from burning up. But it's worth it to be able to stretch each gear out farther.
I have an SRT 4 neon engine thats built, was for another project car but im thinking of pulling some of the internals if they will fit the 2.0
 
What size track are you running? You need to be able to run the car in 2nd instead of 3rd unless you are on a 1/2 mile your probably hitting 5500rpm going into the corners in 3rd i'd guess?

If you want to do the 2.4 swap like dustyboner said then you can run 3rd since 5500 is the upper end of the 2.4's power band so if your looking into that disregard any further info below

To get the car so you can run it in 2nd you'll want to swap to a manual neon transmission instead of the eclipse one. Find one from a 2g neon that has 3.50 final drive gears instead of 3.94 gears. Then also get modern performance PCM. They list them for neons but they also work with eclipses. You can get the rev limiter raised to 8000 rpm. You have to change your rod bearings once or twice a season depedning on how much you race but it's easy enough to do that. I would also highly recommend using ARP rod bolts.

Circle track racing isn't all about horsepower. A lot of it has to do with gearing. I can run my Stock 1993 132 hp N/A 4g63 Eclipse in circles around any cavilaer and most hondas because the gear ratio is just perfect on them and they stay in the powerband. I'm sure you feel the car lug before it takes off coming out of the corners running 3rd because your dropping out of the cars powerband. If your still struggling with keeping up after getting the gearing right then you may want to start building the engine. Put a jeep throttle body on it and bore the intake manifold to match, then add cams, 18 grinds will get you power without a lumpy idle, then if your still struggling build a higher compression bottom end. Building the bottom end is the most expensive to do which is why I listed it last but it will also be the most effective especially couple with bigger cams.
Track is 4/10ths mile and yea im running 3rd gear for the most part. I use 2nd when I really need to get around someone

I have a neon trans sitting in the garage. It's from a 2 door neon with the 2.0. Not sure what year tho. Definitely need a new trans tho, stock one keeps coming out of 3rd gear when I exit the corner hard. Pretty sure the synchros have had enough of the short track life.

Not sure what rpm I'm turning at the moment. Stock tach. crapped out on me and I've been waiting for the adapter for the aftermarket tach I picked up.
 
Well some neon trans
Track is 4/10ths mile and yea im running 3rd gear for the most part. I use 2nd when I really need to get around someone

I have a neon trans sitting in the garage. It's from a 2 door neon with the 2.0. Not sure what year tho. Definitely need a new trans tho, stock one keeps coming out of 3rd gear when I exit the corner hard. Pretty sure the synchros have had enough of the short track life.

Not sure what rpm I'm turning at the moment. Stock tach. crapped out on me and I've been waiting for the adapter for the aftermarket tach I picked up.

You'll want to figure out your RPM. Depending on the track banking you may have to go higher that 8000 rpm to run 2nd gear since your close to a 1/2 mile. More than 8k will require H beam rods to make it last as well as bigger valve springs to prevent float. If your in 2nd gear how far down the straightaway can you get before it hits the rev limiter? If you can get more than 1/2 way a neon trans and 8,000 rpm limiter should be all you need to run 2nd. You might have to go up in tire size a little bit too. Looks like you have plenty of room to go bigger from the pics of your car. I'd do bigger tires last as they will add more rotational weight. But if it's what you have to do to run 2nd it'd be worth it


Some neon trans are 3.94 and some are 3.55. If you don't know what year or engine you'll have to try and find the ID tag. If it has a hydraulic clutch bell housing it's probably a 3.55 unless it came from a Magnum car but that pretty rare.
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Well some neon trans


You'll want to figure out your RPM. Depending on the track banking you may have to go higher that 8000 rpm to run 2nd gear since your close to a 1/2 mile. More than 8k will require H beam rods to make it last as well as bigger valve springs to prevent float. If your in 2nd gear how far down the straightaway can you get before it hits the rev limiter? If you can get more than 1/2 way a neon trans and 8,000 rpm limiter should be all you need to run 2nd. You might have to go up in tire size a little bit too. Looks like you have plenty of room to go bigger from the pics of your car. I'd do bigger tires last as they will add more rotational weight. But if it's what you have to do to run 2nd it'd be worth it


Some neon trans are 3.94 and some are 3.55. If you don't know what year or engine you'll have to try and find the ID tag. If it has a hydraulic clutch bell housing it's probably a 3.55 unless it came from a Magnum car but that pretty rare.
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Can't go bigger on the tires. Tires have to be bought from the track and all cars in the class run same size.
 
The real questions that need to be asked here:
- what is your budget?
- what is your time frame?


There are an infinite number of possibilities. But you'll need to know the limiting factors before you start. With plenty of time and money you can build as badass 420a and still meet the ruler requirements. You could cam it, stroke it, bore it, tune it, rev it, change the ratios, etc. But I can see how that much time and work is impractical.
 
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There's many series of 4 cylinder Honda engines, each being different from the last in some form or fashion. The 420a, if built correctly, will outperform a lot of them. The ones that outperform the 420a are the ones with V-tech or some other form of VVT. And if you're revving your 420a high enough with the right valve springs and cams, you can keep up at least.

A stock 420a is by no means a powerhouse. But many of us, including myself, have spent too much money and too much effort trying to make it something it's not. And we do know what we're talking about. Whether we type our thoughts the way we meant to or not. And we try to keep DSMTuners a greatly useful resource for everyone new to the 420a platform.
 
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a chassis completely gutted except for the windshield, door sheet metal, hard brake lines and the proportioning valve, weighs in at 611-615 lbs
 
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