Where can i get parts for my engine? It's a 84 chevy motor. I looked on ebay, but it was mostly 235 and other engine stuff. Not so much for the 250. Can you guys give me some more info on this engine? Is there any good mods, i.e. carb update, ignition, exhuast, etc. Can't find to much on this engine other than it's long lasting and get's decent gas milage. Any help is welcome, and thank'd for. Kasey
Clifford Performance and Langdons, are the first ones that come to mind. Check 'em out. One quick side note, if your 250 has the integral intake manifold, that will limit the performance upgrade potential. If it does have it, you'll want to conside swapping the head to the earlier non-integral style, whch will allow you to use any of the eftermarket intake manifolds.
I seen a pic somewhere where the intake manifold was made into part of the head. I was curious about that. Weren't these 250's head's port jobs very bad? And restrictive? I'm thinking if i need to get a new head, might as well get it opened up. That way it can actually accept a larger carb. Thanks for the reply btw!
Just checked out those links, and i got to say i will most definatly be doing buisness with them. Not sure which set up to go with though. Here is the choice's i'm considering. First, of course, the 4bbl( i guess about a 450cfm carb?), then the 3x1bbl. I love the way the three carbs look. Which would be best for performance, and still keeping some gas. 3x1? And if i do get the 3x1, can i still put the 1 into 2bbl adapter to have a 6bbl?
Thanks again for those links, definatly awesome sites!
Three carbs are very hard to get running correctly, you have to start with the right ones and each one has to be the same. And when I say the same, I mean exactly the same, year, month, make, engine size, etc..... They should give better throttle feel since the equalize the intake runner length.
The four barrel most likely will perform better since its easer to tune. Use a intake with small runners to keep the air velocity up. Step up to a mild RV type camshaft, and if you have room, use a long tube header. The shorty style headers are great for clearance but not much on torque. You will need to add heat to the under side of the intake if you add headers. The stock exhaust heats it now, and you must heat it if you wish to keep your fuel mileage up.
There are some tricks to adding air flow to the head, just opening them up will not do it. Go to the Inliners.org site and look up Tom Lowe. He will help you out with the head.
Thanks guys, got quite a few hints on the inliners.org so i'm gonna go register over there. And the 250 is in a 84 so i should have plenty of room for long headers. I read something about heating the manifold, how do i do this? Is it going to be expensive? Also, is there going to be a large difference between the engine in the 84 and the older 250's? Thanks again guys.
Heating is easy, use water or exhaust, not cheap but not real expensive either. Good information in the above link. Also a good place to straight answers.
In Brazil we have a car named Chevy OPALA that was build with a GM250 inline 6. We have many custom and performance parts. Here this engine is one of most popular for street and strip aplications.
WELCOME Ricardo! and Thank You very much for the goodies you have available in Brazil. Nice to have you aboard. Tell us more about your car and some underhood pictures would be great. Everyone here loves pictures.
Ditto on the 307 V-8 pistons. They're the same diameter, weight, wrist pin size, compression height and everything, they're just flat tops instead of having the 1/4" dish in the top. On the last one I built like that, I also milled .050" off the cylinder head. It had plenty of power, still used regular gas, and had no problems with piston-to-valve clearance. There was a noticeable increase in the low-end torque from the higher compression. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I iniciate the modifications in my car in 2008, for street aplication. Initialy I use a 4inch pistons, ISKY cam (525B) with 278x278 intake/exaust duration, one 4barrel Holley 750cfm and a spray with 70hp of NOS. The car in street is realy very funy!
In 2010 I change the configuration, with more compression (13:1) for methanol, a CRANE cam (310x320 intske/exaust), a dome pistons, and the same 4barrel (but with some modifications).
On this event, with ethanol, the car makes 2.0s 60ft and 8.6 1/8, but the best car times is 1.9s 60ft and 7.7s 1/8 with DRAG radial and 2.0s 60ft and 8.3s 1/8 with street tires.
This configuration is very popular in Brazil, for street or strip use, meanwhile with 3 40 or 44mm webber.
The best time on this class in Brazil (with street tires and 3 webber) is: 1.8s 60ft, 7,4s 1/8 and 11,6s 1/4 (pilot: Danilo Aizona by Segantini) on Curitiba/PR strip.
movie:
With DRAG radial is 1.6s 60ft, 6,9s and 10,7s (pilot: Celso Camargo by Benato) on Velopark strip.
movie:
However I need some help to the development of my new engine, mainly before read some parts of Leo Santucci´s book and see the movie about Perry and Headrick "Pocket Rocket" car, then win some race on NHRA on late´s 70´s.
What the best block to use on darg race with Drag radial, 250 or 292? And compression rate? 3 7/8 or 4 inch pistons? And the camshaft? With or without lump ports (in Brazil NOBODY use lump ports on the head).
I appreciate any help and get post more pics and movies about TO - Traseira Original (Rear Standart) and STT - Street Tração Traseira (RWD Street) class.
