How much can a 2.5 Take?

slpcamaross97 · 07-02-2009, 02:37 PM

Hey guys.

Finally got on here after looking for a few years. have some crazy ideas. i have a show truck with a 2.5 A code in it now. as we all know they lack some major power. So i had a few ideas

1. Turbo charge the stock 2.5. ---how much can this motor take before it tosses a piston?

2. Was doing a marine 2.5 swap. but looks like there is some major problems and machine work that would need to be done to make it all mesh ???

3. Was Pulling both motor and trasn and swaping in a DSM trubo motor.

I do not want a chevy 350.... i drive it way to much to aford the fuel for it.... and want to keep it simple-er.

My main goal is so be able to pull a little pop-up trailer so i dont have to pay someone to pull my truck up and me pull the camper.

Any idea? truck only has 69k org. miles.

XDime99 · 07-02-2009, 02:52 PM

Why dont you just get an old 4.3 and build it a little, like put a cam in it, p+p the heads, pistons, etc...? That would give you all the power youd need....

slpcamaross97 · 07-02-2009, 03:06 PM

really looking to keep my mpg when cruizing it around. I drive this truck as much as possible in the short time of summer have. i start driving it after 5 good rain storms after winter and will keep driving it till the first little sign of snow. i baged it about 5 years ago and everything is still in geat cond. replaced 4 link bushings.

So really want a little trubo motor in it since i have a ton of room and can fab up a header easy and other stuff i need but dont know the limits of the motor.

beaniebmx · 07-02-2009, 07:14 PM

swap an ls1 in there and get the same mileage with a tune

Steady Eddie · 07-02-2009, 07:28 PM

The connecting rods are pretty weak.

Go forged rods.

The cast pistons (OE) are junk.

Go forged pistons.

The OE crankshaft flexes like crazy, but you have the strongest OE crank already.

Consider having it cyro treated, if it is OK otherwise.

Maximum overbore is .030, otherwise you weaken the block.

The Fiero rubber biscuit front vibration damper will help a lot.

Replace the plastic OE timing gears with an all-metal set from Cloyes, helical cut gears for more quiet.

The OE head flow signs off at about 4500 RPMs.

The OE camshaft is just about perfect, as is the OE ignition.
You *might* like an aftermarket, hotter coil, but there have been QC issues, and they wind up being worse than OE.

OE only has a 1 BAR MAP Sensor, so you gotta change that, and the tune.

THEN you can turbo it, with some degree of life to it.

FarEastDime · 07-06-2009, 12:55 AM

Quote: Originally Posted by Steady Eddie

The connecting rods are pretty weak.

Go forged rods.

The cast pistons (OE) are junk.

Go forged pistons.

The OE crankshaft flexes like crazy, but you have the strongest OE crank already.

Consider having it cyro treated, if it is OK otherwise.

Maximum overbore is .030, otherwise you weaken the block.

The Fiero rubber biscuit front vibration damper will help a lot.

Replace the plastic OE timing gears with an all-metal set from Cloyes, helical cut gears for more quiet.

The OE head flow signs off at about 4500 RPMs.

The OE camshaft is just about perfect, as is the OE ignition.
You *might* like an aftermarket, hotter coil, but there have been QC issues, and they wind up being worse than OE.

OE only has a 1 BAR MAP Sensor, so you gotta change that, and the tune.

THEN you can turbo it, with some degree of life to it.

the only person on this damm site that could give you all that info and it be correct. dont ever question eddie

lesterl · 07-06-2009, 09:45 PM

Yeah, he knows his $hit. We all freak out a little bit when he says he is going on Vacation..... :-)

max1million · 07-07-2009, 09:42 AM

Old hotrod mag article (87) said for a stock short block 180 probably wouldn't last long 140 is more reasonable with 5000 rpm rev limit.

Steady Eddie · 07-07-2009, 01:05 PM

Quote: Originally Posted by max1million

Old hotrod mag article (87) said for a stock short block 180 probably wouldn't last long 140 is more reasonable with 5000 rpm rev limit.

====================================
max--

I read that article, too.

I think that the engine (88-up block and OE crankshaft) will handle 50 HP per cylinder. (if you use the forged parts).

No one on here has ever (to my knowledge) experienced an honest-to-God 200 HP "reliable" Iron Duke engine.

At 200 HP to the flywheel, you enter the realm of the V-8 modded S-10s, with about 1/2 the weight.

The rig would be so much fun to drive, you'd never want anything else.

Freek · 07-10-2009, 12:58 PM

What would the mileage be like at 200HP?

Edit- I'm going to rebuild the 2.5 and maybe do it like that, maybe even the turbo. Engine only has 80K on it.

That's why I want to know.

max1million · 07-10-2009, 02:09 PM

Well the article didn't mention or list any forged parts for that build. It was cam, and head up bolt ons. And it was naturally aspirated build which generally means also shifting the rpm range higher (w/cam) to get the hp, but they limited to under 5000. The hp was only "a more reasonable 140hp" instead of the targeted 180 with "...durability ... questionable". Small turbo may help boost torque/hp starting at lower rpm, to ~4900.

Think I hit 5000 once (all stock) just to see what it would do. It doesn't sound good to me up there. And it flattens out starting about 4500 like you mentioned. Maybe I'm just not used to pushing it (less then 4800). Not much go under 2800 rpm either.

The 200hp+ build was using complete super duty with all the goodies.

More hp still burns more fuel. Well tuned (computer controlled) v8s can get near same mileage.

Freek · 07-20-2009, 12:39 AM

I don't know, the 350 stock gets 14-17 highway. I just want a bit more off the line pull.

BTW that's a 94 fullsize longbed.

92 s10 project · 07-23-2009, 04:52 PM

Carbuerated V-8's are the most common in an S10, and they get not so good mileage. Now if you go and swap in an LS1 and get that thing tuned, your going to get the same mileage you did with the 2.5. Visit the LSX section here and check it out, its pretty impressive, albeit more expensive.

FarEastDime · 07-26-2009, 10:50 PM

Quote: Originally Posted by slpcamaross97

Hey guys.

Finally got on here after looking for a few years. have some crazy ideas. i have a show truck with a 2.5 A code in it now. as we all know they lack some major power. So i had a few ideas

.

i dont beleive you, pics are necessary

07-02-2009, 02:37 PM	#1
slpcamaross97 Registered User Age: 24 Join Date: Jul 2009 Posts: 3 Location: User is: OffLine	How much can a 2.5 Take? Hey guys. Finally got on here after looking for a few years. have some crazy ideas. i have a show truck with a 2.5 A code in it now. as we all know they lack some major power. So i had a few ideas 1. Turbo charge the stock 2.5. ---how much can this motor take before it tosses a piston? 2. Was doing a marine 2.5 swap. but looks like there is some major problems and machine work that would need to be done to make it all mesh ??? 3. Was Pulling both motor and trasn and swaping in a DSM trubo motor. I do not want a chevy 350.... i drive it way to much to aford the fuel for it.... and want to keep it simple-er. My main goal is so be able to pull a little pop-up trailer so i dont have to pay someone to pull my truck up and me pull the camper. Any idea? truck only has 69k org. miles.
	[Reply w/Quote]

07-02-2009, 02:52 PM	#2
XDime99 Registered User Age: 17 Join Date: Apr 2009 Posts: 366 Location: Gainesville, Fl User is: OffLine	Re: How much can a 2.5 Take? Why dont you just get an old 4.3 and build it a little, like put a cam in it, p+p the heads, pistons, etc...? That would give you all the power youd need....
	[Reply w/Quote]

07-02-2009, 03:06 PM	#3
slpcamaross97 Registered User Age: 24 Join Date: Jul 2009 Posts: 3 Location: User is: OffLine	Re: How much can a 2.5 Take? really looking to keep my mpg when cruizing it around. I drive this truck as much as possible in the short time of summer have. i start driving it after 5 good rain storms after winter and will keep driving it till the first little sign of snow. i baged it about 5 years ago and everything is still in geat cond. replaced 4 link bushings. So really want a little trubo motor in it since i have a ton of room and can fab up a header easy and other stuff i need but dont know the limits of the motor.
	[Reply w/Quote]

07-02-2009, 07:14 PM	#4
beaniebmx Has Training Wheels Join Date: Jun 2007 Posts: 2,458 Location: Iowa User is: OffLine	Re: How much can a 2.5 Take? swap an ls1 in there and get the same mileage with a tune
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07-02-2009, 07:28 PM	#5
Steady Eddie Sending Big Oil a Message Join Date: Mar 2008 Posts: 1,001 Location: The Great Pacific Northwet User is: OffLine	Re: How much can a 2.5 Take? The connecting rods are pretty weak. Go forged rods. The cast pistons (OE) are junk. Go forged pistons. The OE crankshaft flexes like crazy, but you have the strongest OE crank already. Consider having it cyro treated, if it is OK otherwise. Maximum overbore is .030, otherwise you weaken the block. The Fiero rubber biscuit front vibration damper will help a lot. Replace the plastic OE timing gears with an all-metal set from Cloyes, helical cut gears for more quiet. The OE head flow signs off at about 4500 RPMs. The OE camshaft is just about perfect, as is the OE ignition. You might like an aftermarket, hotter coil, but there have been QC issues, and they wind up being worse than OE. OE only has a 1 BAR MAP Sensor, so you gotta change that, and the tune. THEN you can turbo it, with some degree of life to it. Last edited by Steady Eddie : 07-02-2009 at 07:34 PM.
	[Reply w/Quote]

07-06-2009, 12:55 AM	#6
FarEastDime WWW.CAROLINATRUCKSCENE. Age: 26 Join Date: Oct 2008 Posts: 1,251 Location: User is: OffLine	Re: How much can a 2.5 Take? Quote: Originally Posted by Steady Eddie The connecting rods are pretty weak. Go forged rods. The cast pistons (OE) are junk. Go forged pistons. The OE crankshaft flexes like crazy, but you have the strongest OE crank already. Consider having it cyro treated, if it is OK otherwise. Maximum overbore is .030, otherwise you weaken the block. The Fiero rubber biscuit front vibration damper will help a lot. Replace the plastic OE timing gears with an all-metal set from Cloyes, helical cut gears for more quiet. The OE head flow signs off at about 4500 RPMs. The OE camshaft is just about perfect, as is the OE ignition. You might like an aftermarket, hotter coil, but there have been QC issues, and they wind up being worse than OE. OE only has a 1 BAR MAP Sensor, so you gotta change that, and the tune. THEN you can turbo it, with some degree of life to it. the only person on this damm site that could give you all that info and it be correct. dont ever question eddie
	[Reply w/Quote]

07-06-2009, 09:45 PM	#7
lesterl Wire Splicin Fool :-) Age: 30 Join Date: May 2008 Posts: 4,346 Location: Harrisonville, MO User is: OffLine	Re: How much can a 2.5 Take? Yeah, he knows his $hit. We all freak out a little bit when he says he is going on Vacation..... :-)
	[Reply w/Quote]

07-07-2009, 09:42 AM	#8
max1million Registered User Join Date: Feb 2009 Posts: 177 Location: User is: OffLine	Re: How much can a 2.5 Take? Old hotrod mag article (87) said for a stock short block 180 probably wouldn't last long 140 is more reasonable with 5000 rpm rev limit.
	[Reply w/Quote]

07-07-2009, 01:05 PM	#9
Steady Eddie Sending Big Oil a Message Join Date: Mar 2008 Posts: 1,001 Location: The Great Pacific Northwet User is: OffLine	Re: How much can a 2.5 Take? Quote: Originally Posted by max1million Old hotrod mag article (87) said for a stock short block 180 probably wouldn't last long 140 is more reasonable with 5000 rpm rev limit. ==================================== max-- I read that article, too. I think that the engine (88-up block and OE crankshaft) will handle 50 HP per cylinder. (if you use the forged parts). No one on here has ever (to my knowledge) experienced an honest-to-God 200 HP "reliable" Iron Duke engine. At 200 HP to the flywheel, you enter the realm of the V-8 modded S-10s, with about 1/2 the weight. The rig would be so much fun to drive, you'd never want anything else.
	[Reply w/Quote]

07-10-2009, 12:58 PM	#10
Freek Shred The Shit Age: 17 Join Date: Feb 2008 Posts: 663 Location: Indianapolis, IN User is: OffLine	Re: How much can a 2.5 Take? What would the mileage be like at 200HP? Edit- I'm going to rebuild the 2.5 and maybe do it like that, maybe even the turbo. Engine only has 80K on it. That's why I want to know. Last edited by Freek : 07-10-2009 at 01:00 PM.
	[Reply w/Quote]

07-10-2009, 02:09 PM	#11
max1million Registered User Join Date: Feb 2009 Posts: 177 Location: User is: OffLine	Re: How much can a 2.5 Take? Well the article didn't mention or list any forged parts for that build. It was cam, and head up bolt ons. And it was naturally aspirated build which generally means also shifting the rpm range higher (w/cam) to get the hp, but they limited to under 5000. The hp was only "a more reasonable 140hp" instead of the targeted 180 with "...durability ... questionable". Small turbo may help boost torque/hp starting at lower rpm, to ~4900. Think I hit 5000 once (all stock) just to see what it would do. It doesn't sound good to me up there. And it flattens out starting about 4500 like you mentioned. Maybe I'm just not used to pushing it (less then 4800). Not much go under 2800 rpm either. The 200hp+ build was using complete super duty with all the goodies. More hp still burns more fuel. Well tuned (computer controlled) v8s can get near same mileage.
	[Reply w/Quote]

07-20-2009, 12:39 AM	#12
Freek Shred The Shit Age: 17 Join Date: Feb 2008 Posts: 663 Location: Indianapolis, IN User is: OffLine	Re: How much can a 2.5 Take? I don't know, the 350 stock gets 14-17 highway. I just want a bit more off the line pull. BTW that's a 94 fullsize longbed.
	[Reply w/Quote]

07-23-2009, 04:52 PM	#13
92 s10 project R/C Guru Age: 22 Join Date: Jan 2007 Posts: 605 Location: St Louis, MO User is: OffLine	Re: How much can a 2.5 Take? Carbuerated V-8's are the most common in an S10, and they get not so good mileage. Now if you go and swap in an LS1 and get that thing tuned, your going to get the same mileage you did with the 2.5. Visit the LSX section here and check it out, its pretty impressive, albeit more expensive.
	[Reply w/Quote]

07-26-2009, 10:50 PM	#14
FarEastDime WWW.CAROLINATRUCKSCENE. Age: 26 Join Date: Oct 2008 Posts: 1,251 Location: User is: OffLine	Re: How much can a 2.5 Take? Quote: Originally Posted by slpcamaross97 Hey guys. Finally got on here after looking for a few years. have some crazy ideas. i have a show truck with a 2.5 A code in it now. as we all know they lack some major power. So i had a few ideas . i dont beleive you, pics are necessary
	[Reply w/Quote]