I don't want to come off too harsh.. but let's be realistic..

You're not going to make 400hp on a budget with a single cam 4G64.

so which dohc should I use

It's not really a matter of which motor to use, it's the 'budget' aspect of it. 400hp can be done on a SOHC 4G64, but it's going to take forged internals, a built head, and lots of other high cost parts to do.

ahhh I see now

The Evo is not a good candidate for the Mighty Max, the engine fitment is wrong, there are some fast Mighty Max trucks out there, you can probably find a few on the forums. The stock Mighty max block is a 4g64 but it is a "wide block" version whereas the cars have the narrow block version, now you could still build a 4g63 or 4g64 from a DSM and install it in your truck, you would need to use a transmission with a matching narrow block bell housing is all. Domestic guys refer to injectors in lbs of flow, import guys refer to them in cc per minute of flow, and a set of 750cc or 850cc or 1000cc shuld do you fine on gasoline for your goals, if your planning to burn alcohol then you might need to find even bigger ones.

thanks for that input

This is what I would do if I were in your shoes...get a short block and transmission from a 2.0 G63B mighty max or d50 pickup, I think the early 86-89 trucks had the 2.0 sohc carb motor, sell or ditch the sohc pistons and oil pump, all you need is the block really, now get some good 1g turbo dsm 6 bolt pistons rods and oil pump/front case, a dohc dsm head 1g or 2g, with a modified intake so the throttle body faces the front of the truck [as opposed to the bell housing], and you will have to mod the turbo plumbing add a front mount intercooler, a 90 dsm turbo oil filter housing, so you can run an air oil cooler, a timing belt kit for a dohc dsm with tensioner, if you use a base 1.8 1g dsm thermostat cover you can avoid blowing a hole into the firewall to get clearance for the upper radiator hose that is on the dohc heads, and now you have an engine that will play nice, you now need a wire harness ecu and sensors from what ever ecu and harness you get, I would guess that you could do all of this for around $2500-$3000 give or take but it could be done for a lot less it just depends where you shop for the parts etc, but I think it makes more sense to build a boosted 2.0 truck hybrid motor on the side that way you can still drive your 2.4 truck, and it gives you some time to plan the build, and do some research, so honestly I think you should do a dohc turbo swap before you even make a power goal, and yes you could turbo the 2.4, but it will cost more then making a dohc 2.0...you might even be able to save some time and use the full 90-94 1g dsm turbo 4g63t motor, if you get a rwd transmission with the narrow bell housing that matches the turbo dsm motors bolt pattern, well if your truck does not have the right pattern already that is, the only way to know for sure is to measure the bolt spacing on the bell housing.

ok thanks for that I’m glad I came here first before doing anything crazy because that makes a lot more sense

yeah making a 4g64 a dohc is sort of hard the pistons need to have lower compression for street unless you plan to only ever run e85 thats why I suggest going 2.0 or make a 2.3 stroker with a 2.0 block if you value the added torque the 4g64 gives.

You also aren’t going to make 400hp on 12psi

Just as an FYI some year mighty max and d50’s did indeed have a 4g64 narrow block.

Not to be "that guy" but psi is relative, 12 psi with the right setup could be more than 400hp... lbs/min is what you should look at to actually be relevant. Sorry to rant and steal the post, just a pet peeve of mine as car culture is rampant with a misunderstanding of psi... For example an hx40 @ 15psi is not the same as a 14b @15psi...


Budget and power don't flow well together, but slinging together used but good quality parts is key.

I don't have a ton of experience with the 4g64's, but best of luck with your mighty max, always thought they would be an awesome sleeper truck!

As far as a budget turbo setup, I'd look into Holsets (HX35's and other variants) they are very available, can put down good numbers, and have reliability(just be sure to route oil properly). The downside is that they do have a bit of laggy-ness, but with a 2.4 it may be less noticeable.

Injectors are gonna depend largely on the type of fuel you have access to and are willing to run.

If you run into issues of high compression, water/methanol injection is a good way to avoid e85 or race gas, that's fairly inexpensive to do (just be sure to have fail safes set in place)

Not sure of 4g64 internals, you are somewhat on the right track with the evo parts idea, as things like evo valve springs and evo intercoolers are a budget upgrade that will be fine for your power range

sleeper1ga said:

Not to be "that guy" but psi is relative, 12 psi with the right setup could be more than 400hp... lbs/min is what you should look at to actually be relevant. Sorry to rant and steal the post, just a pet peeve of mine as car culture is rampant with a misunderstanding of psi... For example an hx40 @ 15psi is not the same as a 14b @15psi...


Budget and power don't flow well together, but slinging together used but good quality parts is key.

I don't a ton of experience with the 4g64's, but best of luck with your mighty max, always thought they would be an awesome sleeper truck!

As far as a budget turbo setup, I'd look into Holsets (HX35's and other variants) they are very available, can put down good numbers, and have reliability(just be sure to route oil properly). The downside is that they do have a bit of laggy-ness, but with a 2.4 it may be less noticeable.

Injectors are gonna depend largely on the type of fuel you have access to and are willing to run.

If you run into issues of high compression, water/methanol injection is a good way to avoid e85 or race gas, that's fairly inexpensive to do (just be sure to have fail safes set in place)

Not sure of 4g64 internals, you are somewhat on the right track with the evo parts idea, as things like evo valve springs and evo intercoolers are a budget upgrade that will be fine for your power range

Click to expand...

You are 100% on point with this, ideally you wouldn't want any boost at all! you would want your engine to be able to flow every bit of turbo air output and match it with fuel. Lets look at what "boost" is... and that is extra air in your cars intake from the compressor outlet to your valves that cant fit into your cylinder for reasons such as poor head flow, small displacement that cant hold anymore air, cams that wont hold the valves open long enough to allow more air into the cylinder at a given rpm, piston speed vs valve timing events that prevent air from filling the cylinder any further, etc. That being the case, a better flowing engine with the same turbo will actually show less boost and make more power than a high boost poor flowing engine will, as said its all about the magic of air flow and lbs per min and density of the air.