Inliners International Forums General Discussion Hi Performance starting a new learning curve

hello to everybody. for the past ten years i have built plenty of sbc's with my father in the back yard,keep in mind im 25 now, and by now the understanding for them come really easy for me. 2 years ago i traded a 86 grand national to a 1940 chevy with a 230 inline. my goal was to take the inline 6 out and replace it with a 383 untill one of my uncles said "you see v8's everywhere, why not try to make power out of your inline 6" after he said that... my mind changed. so now im starting the learning curve. i have done some research, and orded the power manuel by leo(yesterday) and am wanting some advice. here is what im working with: 1940 chevy cab with a 1929 ford bed sitting on a s10 frame, stock 4cylinder rearend(373 gear i think)with a stock 230 out of a 1965 gmc van or chevy van not sure with a th350 behind it. truck weights 2560 with me in it. tires in the rear are 28" tall hoosier street tires.ok for the first question what is the best way to start adding some hp without tearing in to the gutz of the motor?(bolt ons) and what can i expect as far as gains.i found a good deal on a 292 that came out of a 80s one ton for 100 bucks, this is whats replacing the 230. 292 will be a brand new motor.(except for block and head)and i would like to know what is the max hp and tq i can get out of this motor with stock style head.(i will put lump ports in it). my goal here is to make a prostreet inline 6 ratrod that will be drivin a lot and might go down the track a few times just to see what she has. thanks in advance mike

Its relatively easy to reach 300 HP with either a 250 or a 292 in N/A form. The 292 in bone stock trim makes 300 ft.lbs. of torque above 2000 RPM and beyond, so torque isn't a problem with that engine. The stock type siamese head can also support 600 HP and beyond with various degrees of porting and lumps. Turbos and/or nitrous have pushed these engines to 700 HP and beyond as well, so the range of performance is very wide and parts are available for whatever you want.

thank you cnc-dude. my next question would be what kind of cam would be great for the street and give me the best of both worlds(street and strip)? i dont plan on taking the 292 past 5000 for obvious reasons. rotating assembly will be balanced with hd flywheel aftermarket harmonic balancer recondition stock rods and after market pistons.what would be the max rpm i can get out of the motor? mike

Mike,

Just curious if you considered a 4200 late model inline 6 out of a trailblazer. Stock they make 275 or 290 HP depending on the year. Way better mileage than a 292. With a low boost turbo (8 psi) 400 HP is real easy to get.

i see your point but i think im going to stick with the 292 thanks though efi.... i do have another question though.. somebody told me that 3-1 intake would work better then a single 4 barrel is this true? would a 3-1 with progressive linkage be better? mike

The 4V would work just as well - buttt - I love the looks of multiple carbs on a six.
Your call.

Mike,

In the 'Tech Tips' section of this site, under 'Cam Specs, 250" Series Engines', a listing of cams for the Chevrolet 194-230-250 engines is shown. This list should be very similar to those available for the Chevrolet 292 camshaft, which has the fuel pump lobe in a different location.

Other guys can add in here, for a street/strip cam, consider .050" duration in the 208 to 218 degree range.

consider it a .060" over 283 small block with better bottom end torque (4.12"stroke)- what would you put in it?

The camshaft needs of a 292" L6 and V8 are as different as chalk and cheese.

Theres needs and wants.

For chalk, think of it as bored 283 for carb and exhaust sizing.

The 292 seems to have combustion chambers that somewhat resemble Pontiac v-8s and both thrive on dual pattern camshafts, maybe,the 292's would like 30 degree intake seats (Pontiac ace Jim Hand says they work better than 45's in the ponchos up to .400" lift, and most cams go to .400" or more during lift and closing-and if your'e gonna do a valve job, the 30 degree should not cost any more than a 45)).

For cheese, maybe one should think of the 292 six as a 400 Pontiac when it comes to cams and try to pattern a smooth cam such as a "P" cam 197/213 @.050 113 lobe seperation; or an "S" cam 212/225 @ .050 116 lobe seperation both with 113 intake centerline. Some Pontiacs did come 1.65 rockers instead of 1.5's.
Its hard to beat a Pontiac for torque. as ol' Hank says, IMHO.

The cylinder dimensions are far more important than the total displacement.
All wedge chambers are pretty similar regardless of brand or size: Chrysler A & B, Olds early and late, Buick 400/455, SBC, Cadillac, FE, Windsor... it's a long list.
Dual pattern cams are useful to correct flow differences larger than the traditional 100/75 split (although there are other fine-tuning purposes), but it's not closely linked to chamber design.

well, one pontiac 400 cylinder is about 50 cubes, and so is a 292 cyl.

The dual pattern cam tends to aid in manifolding/porting faults which you could say both D-port Pontiacs and 194-292 chevy sixes have.

the pontiac and chevy sixes are more similar than either is to the small block chevy chamber-why not "borrow" all you can from the other engine "camps". Jim Hand has made a lifetime out of researching every thing about Pontiac engines and living with, and adjusting to their "faults". A lot of his recommendations make for big torque numbers over their limited rpm ranges-neither of which are much over 6000.

Right, just use the one from the Pontiac V8 with the siamese ports...

Uuuh, on the intake or the exhausts?
Absolutly no adventuring spirit-are we so all knowing and set in our ways that virtually all is known and no more braincells are to be made available for possibilities that there might be other worthy ideas to apply to our workhorses.
Check out what Phillip Smith had to say about the Bristol triple carbed siamese ported six, wonder if jim headrick knew that and retinkered his cam timing/indexing as a result.
We hold no corner on the market of engine science.

http://www.youtube.com/watch?v=bQKvdHkfTms&feature=player_detailpage - - - - - -This a 292 my cousin and I built last year to put in a 47" Diamond T hot rod I'm gathering parts for.Kevin Self did the lump port head,Raymond Grice did the Ferrera valves and K-Motion springs and valve angles. It has 12 cc dish JE pistons, .231 dur. 565 lift Engle, Bill Smith push rods, Harland Sharp 1:75 rockers. Glen had a ATI Super Dampner with a # 88 durometer rubber made for it also. It's smooth as silk. No dyno info