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Discussion Starter #1
I have a 632 cu. with a set edelbrock heads done by curtis boggs. my engine is 15.1 compression. cam specs in 918 ex 875 lift intake duration at 50 is 286. exaust is 304 lobe seperation is 115. cam is degreed straight up. super victor intake. pro-systems carb 1600 cfms. Q-16 fuel. The car weighs 3200 pd with driver. 411 gear. power glide tranny 30-10.5 tire. Best E.T 5.44 at 128 in the 1/8 mile. I know the E.T will pick up with the right convertor. 60 ft is not good. This motor should make atleast 1125 to 1150 hp. I think or am I wrong? My friend has a car thats a 100 pds heavier. 632 cu inches with head hunter heads and his motor made 1133 hp. and his car is 4.5 mph faster then mine. anyone with any suggestions? anyone build any engine close to this with these heads. I'm not taking anything from curtis, I know he doe's great work. I'm trying to figure out a solution to my problem. thanks mike
 

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Can you advance the cam easy, Just make sure you have enough piston to valve clearance.
 

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If you know the converter is off I'd fix that first.
 

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Discussion Starter #4
I'm putting another convertor in tomarrow. trying it this weekend. Can't advance the cam. I only have 90 thousands now counting lash on the intake. I could but hate to.
 

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Is your gearing right? 4.11 sounds pretty conservative for an NA setup. What do you shift at and run the traps at?
 

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Converter and gears for sure... I'd go 4.30's out back and get yourself a custom spec'd converter....bet you'll wake up a bunch. I'm looking at Ultimate Converters for my next purchase.

You may also want to consider going 113 on the ICL.... I have a similar cam.. 588ci with RFD Mod'd BMF385's... and reworked Brodix HH Intake... I run Q16 as well with a Big Bore PS Dominator.... went with Curtis' recommendation on cam grinder.... tad smaller than yours.. and about identical duration specs. I have not had mine to the track yet with the updates yet, looking forward to it.

Sounds like you have a real nice combo... @ 3200lbs, shiot!!.. you should go 8.40's easy 1/4mi 162ish mph.... and I agree 1125 1150'ish HP range.

Gears and converter and she'll rip...

What do you go through the traps at rpm-wise?
 

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I'm coming up with about 1042 HP as installed in the car based on your 5.44 @ 128.

What track do you run at? Actual elevation? Density Altitude on run?

Can you post the whole timeslip?

What fuel system? What headers/exhaust? Did Curtis or someone do the intake too? If not, there is likely some power hiding in the intake.

Did you make Pro Systems aware you were going to be running Q16 fuel? If not, have you tuned for it?.

What ring package? Vac. pump? What kind of oil pan? Pan capacity?

What RPM are you shifting? What RPM are you crossing the stripe? Do you ever run the 1/4? If not, you could probably use some more gear. What size heads? What size valves?

Have you done a leakdown test? Compression test?

I would eliminate some variables and cut to the chase and pull it out of the car and stick it on the dyno. That will nail down if it is engine itself or the car/installation.

Jason G.
 

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You just got to keep testing making one change at a time. My car is a 68 camaro at 3310 lbs and runs high 5.30's at 130. I have 12 passes on this new combo. Its a 632 with dart 355 heads and super vic fixed by BES. 940 lift with 276 int and 300 exh on 115 lobe sep. Convertor is a 9 inch 5800-6000 stall, 4.10 gear and 28 x 10 M/T. Its making around 1140 to flywheel on Q 16 which was worth roughly 40 hp on limited tuning. Going to a 1550 carb from a 1300 made 20-25 more. Compression is 16.25 to 1. I am surpised that some of these newer heads flowing close to 500 cfm dont seem to be any faster than these small 355's i got that were fixed up 5 years ago with a 2.30 int valve. Might flow 440 to 450 tops. Maybe the cranking compression being around 300 to 320 makes it run. I almost switched to a larger runner cause everybody said they were way to small of a head for those cubes. I believe with more passes and new tires I can get some low 30's out of it at around 131. Good luck
 

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Have a 598 with CFE 385's. Had Pro Systems Spec a 1250 for Q16 Specific. Stock QF 1250 didn't cut it for Q fuel
 

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Why didn"t you tune the engine on an engine Dyno.? If you did you would not have to guess about the converter. or the tuneup :smt102
 

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X2...what Clevo said! All that investment in the engine and you missed the most important part. :) Takes a lot of guess work out of the car set-up , forget about just the power and torque number , look at what RPM for power and torque , fuel curve , timing , jetting , and on and on. Then you have a baseline to set-up everything else. Our customers don't get a convertor until they have a dyno sheet...usually gets them close with the right guy doing the convertor. I'd definately start there too...the wrong convertor...makes the engine builder stupid. Seen it a hundred times! Looks like an awesome piece...good luck getting it sorted out. Johnny
 

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5.44 @ 128 in a 3200lb car is around 1100hp. The ET matchs the MPH so I don't think the 60' could have been that far off, around 1.28-1.30. You need to give more info on the combo, titanium valves? what kind of rods? what oil? ring gap and ring package? base circle of cam etc. Are you in Arizona or Denver with a high DA? You never know what you have until you put it on the pump.
 

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Mike,

Over the last few years I've been trying to help you with this thing, .. I've said the same thing, .. the engine needs to go on a dyno an be checked, as there's
a 100 things that effect power, .. and to get 1150 from ANY conventional head engine takes a great deal of skill.
Doing things like running STUD mount rockers with a .900" lift cam and 1100lbs of open pressure isn't the way to get there.

You swapped head from a 410cfm to a 470 cfm head, .. and the car gained NOTHING, .. you've now had me do a free update and made other changes
and you've gained NOTHING, .. really, doing you think it's something else?

It's in the combination as the performance of those heads are VERY, VERY well documented.

curtis
 

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What are the cam specs? 286 does not describe the intake lobe. what is it at .020, .200 what is the lobe lift?

Honestly, for not having your converter figured out, nor your gear where it should be, and the likelyhood that the cam is soft... it's not running too bad IMHO.

Not unusual for a converter to pick up 1-2 tenths.... gear change to pick up more, etc.... you run 5.40's n/a at 3200 pounds with a mild effort .... your goals are attainable, with more work.

If you are making sweeping engine changes with no et-results, you likely have a driveline issue.... if the engine is isolated from the problem. Converters can suck up a bunch of power if they are not healthy, same for a trans.... bent rear end, things of that nature.

I can't believe how many people are at the track if I offer help to push their car, and it won't move....

As an engine guy, don't disregard what I'm saying next because it's a constant problem. - Guys put all their focus on an engine. If the engine is healthy, and the car has never produced the results you thought it should, concentrate on the REST of the car... leave the engine alone, run it to death and figure out the car. Work on the trans, work on the converter, work on the gearing, work on the shocks..... work on making the car roll by itself basically.... THAT is where you find ET. Looking at the engine constantly to find et.... is emptying your wallet, and your sanity.
 

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I can't believe how many people are at the track if I offer help to push their car, and it won't move....
Isn't that the truth! Bent housing, pro gears that are bent-over and about to die, brakes severely dragging, destroyed bearings....

Amazing the things people over-look in their cars at times.
 

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Discussion Starter #18
Thanks guys for the info! I know my convertor is holding me back. The convertor i'm trying this weekend stalls 6500 in 4 other cars thats over 600 inches. everyone has picked up going to this convertor. and after this weekend im taking this engine 5 hrs to a engine dyno. should had already done it but money is a issue. just now got my motor is one piece the way i wan't it. I'm affraid i'm going to be disapointed when i dyno it. The convertor that i'm running now stalls 6200. I have a 169 1st gear and drops 700 rpms between gear changes. tranny has been refreshed. I'm not running the mph the other 600 inch motors are running. It may very well be in the car and chassie. after the dyno then i will know where to focus my attention. More info on engine. Im running a magnum crank. bill miller aluminum rods. moroso eliminator oil pan. hell fire low tension rings. gas ported pistons. cz vac pump. magna fuel pro-star 500 fuel pump with 5/8 fuel line 6 to 7 pds fuel pressure. My headers are alittle small with 2 1/4 primarys. cam is a 50 mm journal. 4/7 swap. I did a leak down last yr. it was 8% or less. I worked with cutis on this thing Last year. Im not taking anything away from curtis, he was very supported. Sorry curtis if i affended you. thats not my attention. just trying to find solutions. I ran stud mount rockers and my pushrods were not heavy enough. I didn't have enough push rod clearance in the head because my cam is raised 600 thousands. but I got that issue fixed with shaft mount rockers. also upgraded from a 1300 cfm carb to a 1600 carb and both are set up for Q-16. After the pushrod and shaft mount rockers and carb swap i gain nothing from last year. The elevation where i run at. not sure. it's in southern arkansas. also i'm trying new Q-16 fuel. my fuel is almost 2 yrs old. kept it sealed in a dry place, but never know. Thanks guys!
 

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super victor intake
Carb and heads won't work if can't get through here. Is this stock?
 
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