get me to 70...
 

97 donzi 25zx. runs 62 now. how can I get it 70 without making it suck fuel (supercharger) I would like to do cams and headers, but is this going to be enough? 454 mag, previous owner said it was a HO 340hp, but I don't know how to confirm...

fixx
 

either way it will coat the same weather you go more cubic inches or the bower..you mat be able to change to the 110 cc edelbrock heads and cam change with a pcm program mat get you close but you will get better results with the procharger..

$$$$$$$$$$$$$$$$$$$$$

To get 8 mph, you need to add 120hp.

First thing is to figure out what you have. No such thing as a 454 HO 340hp. What does it say the engine is on top of the intake??? It should say 7.4, 454 efi, or something similar.

454 magnum. Thunderbolt ignition.

Carb model

^^^^ Yep, probly $5000 min in parts alone. by the time you do cam, valvetrain, exhaust, intake, carb, fuel pump, gaskets, and all the other misc stuff needed to go along with it you will chow up $5000 in no time flat.:eek:

i just added 110+hp to my 454MAG, didnt quite get 8mph yet but i still have to dial in a few things a little on the motor, and then get the prop right also to work with it.

If it's a 454 mag carb I recommend a supercharger as the cheapest and easiest way to get 70+.

I believe 1997 was the change over year for some 454's...?

Find out which internals you have, if forged, go with a Procharger as Fix pointed out. It is not cheap, prepare to spend AT LEAST $5000 as stated above, I would say more like $6000 to $8000 to do it right.

I installed a Procharger on my 454 Mag, along with some porting, fuel delivery upgrade, head and exhaust port work, stock crank and cam etc etc and went from 65mph to low 80's.......:coolcowboy:

Good luck with it, if you go this route ask questions here, there are a lot of guys who know their stuff and are more then willing to help.

When/if you need the ECM reflashed send it to Mark Boos, or if you are in the same neck of the woods as Eddie Young, have a chat with him.....

I have a 525sc 1997 I am finishing up a refresh on . Rebuilt blower , all new pistons, rings , bearings,gaskets, heads redone, thunderbolt distbuter and cmi headers and tales for bravo. I could give it to you finished or cheaper if you want to use your excessories $7500 out the door. Your motor can be sold to recoup some cost . You might get 2000 -2500 for yours maybe more. Your motor isn't a blower motor it could be a real pain in the ass and will cost alot more I've tried it spent alot and wasn't happy .

Then that is a 365hp engine. Its a decent candiate for supercharging, but that depends on the hours on it. I would not SC it without at least a top end refresh and better head gaskets.

A good cam, intake, carb and exhaust combo will get you about 450-475hp.

Either scenario, you are looking at 5k to get the power to get to 70.

Your best banfg for the buck is to get your prop labbed by BBlades. For $400 or so you can gain 2mph or more.

Upgrade the exhaust valves to inconel or Ferrea super alloy while the heads are off if you are planning to run the supercharger. Good insurance. I am 99.7% sure that the black engines just have standard stainless exhaust valves, and that Merc only put the inconel ones in the blue engines.

I have a gen 4 HO for 4k efi making 500Hp. Add a Once over by Bblades and you are there.
http://www.youtube.com/watch?v=L__3xcJfbjs

I would put blower pistons and high temp rings to the list just keep growing until you spend more than the cost of switching motors.

The "cost" of building or "switching" motors to somebody elses "used" motor is subjective........some people want to build their own instead of buying a complete used motor that someone else has built, history unknown, nothing wrong with that......but who knows what they are buying with a "used" motor.......yes a new motor can cost a lot although as long as it is done correctly and maintained, a new motor should last a while..........IMHO....:coolcowboy:

exactly!!:coolcowboy: thats why im banging your x old lady:hitit:many times,she was well used and abused :drink:

You know as well as I do that it does not matter a bit new or used. They all can have issues, yes even a new rebuilt one. I think what you are trying to convey is warranty is worth the $. I have been down both roads and have had decent luck with the used if you can sort out the junk. Check the video does that sound like a pile? These motors push a 10k lb boat to 90 mph no problem. If the person wanted to spend or could spend 10k I would advise him to avisit a reputable builder.
IMHO!

I would build a 525SC clone. Pull the heads and make sure everything up top looks OK. Replace your intake and exhaust valves and full roller rockers. Put on a 177 Weiand with an 850 Holley. Run 4 lbs of boost and run 2 temp range cooler spark plugs. Install a 120' thermastat. Add a higher flow fuel pump and monitor fuel pressure and boost as a minimum. Then lab finish whatever prop you end up running. I think this will get you close???

In my opinion this is a good place to start. Your 454 Mag has good components. The 8.8 compression is a bit high. The weak link are the intake and exhaust valves and the stock exhaust is only good for 450 PSHP at best.

I know it takes a lot of HP to gain a so