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Topic Review (Newest First)
03-26-2019 04:17 PM
ericnova72 Custom built Tight 2600-3000 rpm stall, built on a 9.5" or 10" core....not a sloppy slip built on a 11" or 12" core.
Freakshow Performance is one source....FTI is another. Hughes, Performance Automatic(PA), BTE are a few more. Jegs even has decent stuff in their own Jegs house branded stuff, but it has to have the designation "XHD" in the description to be the good ones, (made for them by Transmission Specialties IIRC)

That off-the-shelf/mail order house catalog stuff like B&M, TCI, ACC(Boss Hog) is slip and slide junk.

Expect to spend between $300 and $400+....anything cheaper will be junk too.
03-26-2019 07:04 AM
Cutlass92 Whenever I get to that point of adding a stall got any suggestions of one that I should use that’s still streetable and good for cruising
03-25-2019 10:31 PM
ericnova72 I said in an earlier post the cam would be the very last thing I'd upgrade....after the rear suspension bars, bigger carb, bigger intake, better headers, heads, rocker arms, and all the related parts, tires, adjustable shocks, and probably even after a stall converter.

I'd keep the cam you've got, you'll be surprised on how well it will work with the bigger heads.
03-25-2019 08:43 PM
Cutlass92 Eric I have one last question you said a cam upgrade would be a good change too.’I currently have the xe262 is there a different cam you have in mind
03-25-2019 11:45 AM
Cutlass92 Bogie Vette and Eric appreciate all the help and advice. I’m going to do my budget make sure I get everything I need and get to work hopefully sometime this week. I’m glad I came here and asked this question and got all this information cause I was seriously considering a crate engine swap or possibly supercharging it if I had found it first but you’ve shown me changes I can make that will increase power and it’s within my range I appreciate it all guys
03-25-2019 08:50 AM
BogiesAnnex1
Quote:
Originally Posted by Cutlass92 View Post
Hmmm quite a few options too choose from thatís good too know. Iím honestly more leanient towards keeping my rims but Iím still undecided as itís the last on my list after everything else is done so Iíll weigh my options on that. I also wanted to mention that Iím fairly handy with cars Iím not a master mechanic but I do know a thing or two. Would the head swap and everything be something thatís not extremely difficult or would it be something that I should let a professional do. If so is that something thatís usually pricey to get done. I have an estimate from someone I just want to get some opinions to see if itís too high or too low
Head swaps are not difficult but are tedious with a lot of bolts, cleaning, keeping trash and coolant out of the engine, and keeping where the parts came from straight. You need standard tools and a 1/2 inch drive torque wrench.

Drain the coolant and disassemble carefully to minimize how much gets inside the moving parts, obviously an oil and filter change will be part of this. Keep the components of the valve train in order especially the lifters/tappets with the lobe they ran on this is critical if not one lobe and lifter have a very high chance of being wiped out. Also, a good idea to keep push rods and rockers matched as well but while important isn't critical like lifters to their mated cam lobe. Plastic organizers are available for this or you can devise something from cardboard to freezer bags for sets of parts with markings where they mate to.

GM heads can reuse rockers and push rods, aftermarket iron also. Typically aftermarket aluminum heads position the spring perch .1 inch higher from the chamber roof to make room for a taller port and accommodate thicker metal thickness cross sections, this sometimes happens on aftermarket iron heads as well. So these in addition to usually using a 2.02 intake and 1.6 exhaust valve instead of the factory 1.94 and 1.55 valve set, the aftermarket heads often use a .1 inch longer stem. So you need not only the proper valve in head diameter but also longer stem. The installed spring height and retainer with locks remains as GM for 11/32 stems, you have to watch for heads using 8mm stems as these take metric retainers and locks so the spring retainers and locks have to match the spring diameter and the valve stem diameter. Not difficult as it sounds just read the part descriptions and keep them in order by sizes or buy complete populated heads.

Those heads that use a .1 inch longer stem will also require a .1 inch longer push rod. If you keep the cam and rockers you have you need to know the push rod length in there now then add .1 inch. If your making cam and or rocker changes you will have to go through the push rod length drill (tour the web for details and videos) to select a length proper to the stated needs in these information sources. Keep in mind that nominally Chevy SBC with flat tappet lifters use a push rod of 7.8 inches length, the factory roller lifters use one of 7.2 inches.

Depending on rocker type that being self guiding or not self guiding the push rod material treatment can be different, where self guiding rockers are used the push rod can be unhardened or hardened it doesn't matter, however, for a not self guiding rocker the guiding function becomes guide plates or cast slots rubbing on the push rod which requires a hardened push rod.

Head gasket thickness will contribute to compression ratio and squish/quench clearance. A lot of aluminum head sellers use a thick .053 gasket, these lower compression ratios and increase the squish quench clearance neither of which is desireable. There are .028 composite gaskets out there which combined with the SBC piston being typically .025 in the bore at TDC is a lot better for compression and offers a better squish/quench at .053 instead of .078. FelPro sells a polymer coated .015 shim gasket that nets out at the magic .040 clearance for best squish/quench effect and preserves the compression ratio. Shim gaskets require the decks be in great condition, the composition gaskets tolerate more deviation from straight and smooth surfaces. There are a lot of online compression calculators to help you through these calculation as well as us here.

Bogie
03-25-2019 08:13 AM
silver74vette I think that last thing you want to think about is the head gasket that you will use. Getting the most compression with the proper quench will help you get the most power out of it.

When you have the top end of the engine take your time cleaning the gasket surface and don't use scotch brite, they have aluminum oxide which will get all over and destroy your bearings and cam. It takes at least an hour with a pack of razor blades to get a head surface clean. Make sure your torque wrench is accurate as well, head torque is critical.

Good luck, I am really happy with my new top end. Hoping for some warmer weather, have the air gap blues when it's cold and trying to make power below 2000 rpm.
03-24-2019 09:28 PM
Cutlass92 Ok glad to hear it I can definitely do those things for sure. Anything else I might need to consider
03-24-2019 07:29 PM
ericnova72 Yeah, the spring jackers have been added to lift the rear, usually because the stock spring is just worn out due to mileage and sagged out. They certainly don't help traction at all. A new set of springs would be a lot better deal.

if you can change an intake and retime a distributor, you are easily capable of changing a head...it's just bolts, cleaning of gasket surface and threaded holes, and turning a wrench.

Anything you might get stuck on or have questions about the gang here at HotRodders will be able to guide you through it.
03-24-2019 06:05 PM
Cutlass92 I forgot to mention while I was looking around at the suspension I noticed that the previous owner has what we call in Georgia “screwups” in between the coil spring my guess is it was there to make the car sit higher. Is that something that could be affecting my traction suspension wise https://www.jegs.com/i/JEGS/555/60837/10002/-1 That’s pretty much what it is
03-24-2019 06:00 PM
Cutlass92 Hmmm quite a few options too choose from that’s good too know. I’m honestly more leanient towards keeping my rims but I’m still undecided as it’s the last on my list after everything else is done so I’ll weigh my options on that. I also wanted to mention that I’m fairly handy with cars I’m not a master mechanic but I do know a thing or two. Would the head swap and everything be something that’s not extremely difficult or would it be something that I should let a professional do. If so is that something that’s usually pricey to get done. I have an estimate from someone I just want to get some opinions to see if it’s too high or too low
03-24-2019 05:16 PM
ericnova72 For a stock 15" x 7" Rally wheel, the 255/60-15 or 275/60-15 Mickey Thompson E.T. Street SS radial. The 255 is the better fit, the 275 really needs to be on an 8"+ wide rim to work well.
They have a 275/40-18, it needs a 8.5" minimum rim width and is recommended for a 9-10" rim

Hoosier D.O.T. Drag Radial 235/60-15, it is near the same width as the MT 255 but it is shorter in height which would make your rear gear seem a little steeper.
Hoosier does make a 245/40-18 if you wanted to keep the rims you have. On the street you wouldn't be able to tell a traction difference between these and a 15" diameter version, but at the track a 15" would be a noticeable bit better.

M&H Tires also has a 235 size, it has a bit more grooving than the Hoosier or Mickey T's and will last a little longer, compound not quite as soft but still works well.
M&H also has a 245/40-18

There is also Nitto and BF Goodrich Comp T/A Drag radials,
I have no experience personally with either...they are harder and longer wearing but don't hook quite as well. More streetable for some daily drive-around use, and if caught out in the rain.
03-24-2019 04:18 PM
Cutlass92 Meant to tell you also I gotta chance to do a little run with my bro and his challenger. I got em good off the take off then he end up running me down at the end and I couldn’t catch em my tach gauge was basically stuck at 4500 wasn’t accelerating anymore so I pretty much lost that
03-24-2019 04:15 PM
Cutlass92 No it’s not a daily driver mainly just a toy and drive to the corner store or grocery store things like that. Won’t really see wet weather either. I’m debating on keeping the 18s or just getting some 15” cutlass rallies as they’re plentiful where I live.
03-24-2019 03:16 PM
ericnova72
Quote:
Originally Posted by Cutlass92 View Post
Eric what would be a good size tire to get with those drag radials
What rim size do you have or are you planning to use second set of rear rims with a Drag Radial??

Is this going to have to deal with wet weather?? (Some of the Drag Radials have a very minimal tread groove pattern).

Tire wear...is this a daily driver and you expect some reasonable tire wear life?? Some of the drag radials driven daily will be lucky to last 2500 miles....and that's if you rarely really hit them hard or burnout with them.
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