I just had my car dynoed for the first time yesterday. Highest number was 245 HP at the rear wheels (obviously). My best times are 13.326 @ 101.16 in the 1/4 mile and 8.45 @82.45 in the 1/8 mile. Waddyuthink? They said the with my TH350 tranny it is estimated that 22% of power is lost from the motor to the rear wheels, which would yield about 314 HP at the motor. I think the 91 L98 is rated at like 240 hp. I just have bolt ons but I have a lot of them (see sig). Just Superram, SLP headers, Borla catback and other miscellaneous add up to mayb 3000 or 4000 dollars, so that's about $50 plus PER HP. How does this match up with others experiences ?

wow thats a helluva ET to have 245 hp.......

i have around 230-250......and i ran a 15.4 at 89...that was at really high altitude.....on a really high moisture day...with a really bad exhaust leak...and needing a tune up.....but still i wouldnt gain 2 secs!!! lol....i htink that dyno was somewhat low!

What are you basing your HP numbers on? Im trying to figure out if the dyno is low as some at our club meet there suggested, or dyno numbers at the rear wheels are normally in that range for those times. My car runs consistent in the range I mentioned, yea those are the best but we are talking 13.3 to 13.4 and 8.4 to 8.5, not some one off lucky run.

very nice et with only 245hp. I ran pretty much identical et's with 325rwhp. What was ur 60' ?

1.84 to 1.85 for the 60" times for the ets mentioned above. So you had your car dynoed and got 325 rwhp?!! Interesting, you trapped 107mph but with a much worse 60' time. Im only trapping 101 or so. If the rwhp number for our cars are right, you'v got a traction problem. If you can hook up I would expect youd be running in the high 12s.

We are thinking these dyno numbers are low, but maybe not. I have no traction problem,Im running Nitto Drag radials and I heat them up real good before racing.

In looking at you sig more carefully, I don't see anything that would indicate an 80HP increase over my car. Im wondering about the dyno numbers

I ran 13.4 at 100 with 245rwh.

I checked out your car on Cardomain, and you've done all the same bolton mods as me, with different parts, but still, intake and exaust.

Well, maybe the dyno numbers ARE right?

If u were referring to my dyno numbers, it was in my 02 ws-6. I never dynoed my thirdgen. Steve (87tpi) now owns my old car, he ran 15.7@88mph with loose intake and runner bolts. He was surging badly.

Oh my bad. I didn't notice is was an 02. Still that seems pretty high rwhp for an LS1. What do does GM rate them at, like 350 at the flywheel or so?

gm rate them 320flywheel hp. I've seen stock ls1 dynoed ranging from 290rwhp- 330rwhp stock. Every car acts differently. I do indeed have a factory freak. The saem time i had my dyno, my friend got his car dynoed. 02 ss with longtube headers, catted y-pipe, gmmg exaust, slp lid, and a crappy diablo tune and he put down 333rwhp and 346rwtq. he was pretty upset that i nearly dynoed nearly the same tq numbers and was 8rwhp less then him.

Well like I said, and you probably already know this, you need some ET Streets or drag radials to run at the track. If you get those 60 ' times down to 1.8 or less you should be running low 12s easy.

Maybe its those snappy tailights

what stall speed is the converter your running along with what is your gears? these plan a huge roll in a cars low et in comparison to power output.

Sounds about right, my best is a 13.4 and my car dynoed at 232rwhp before some more mods that i've done

Good point. Im running 2800-3000 stall converter with a race built TH350 Transmission and 3.73 gears. As I said I also running Nitto Drag radial. All of these things contribute to a relatively low 60' time and improved et, compared to a stock LS1, for sure

ya, but my rear end is gonna give pretty soon. Saving up for a 9 inch with 3.50 gears for street and 4.11 for track. Then i get some ET streets

Ran 13.67 @ 100.8 with 252 rwhp here.

sounds good, I ran a 13.21@104.63 a few years back. I dynoed my car 2 months ago and made 251.29 RWHP with my bolton in my sig

cause with my 4000stall converter and 4.10's with the old 305 combo, i went 13.03@103mph.

I've dyno'd as high as 253 HP and 362 FT LBS on a Dynojet. That was before the 2,400 Vigilante converter so it's probably down a little now.

a buddy of mine at the track did 240's at the wheels.. not sure exactly what it was. he said 240ish.

the car goes 13.6's at 100 or so. he has 3.70 gears which is a tad too much gear for that car.

his 60's are 1.93.

on a lower 1.8x i can see 13.4's. 13.3s is pretty darn good!

One thing to consider is how much does the car weigh? Same hp and start adding or dropping weight will change the numbers in a hurry. More importantly than is what is your hp to weight ratio?

How are you making 230-250 RWHP and only running 15.4s? My 5,500# van was making 275 RWHP from its hot 312 through the mufflers and ran a 15.2 @ 96. With the current 350, it is making 218 RWHP @ 4,800/ 339 RWTQ @ 2,600 (Mustang Dyno). It has turned a 16.08 @ 87.6 with a 2.08s 60' time.

I need to run where you guys run!!!

LS1 cars here run mid-high 13's even low 14's........

LT1 Cars run high 14s' Low 15's

so 15.4 is about right for my 305....

Well it sounds like the dyno numbers are about right compared to these other times and rwhp combos. This is the first time dynoing and I guess I was just expecting a higher number, wishful thinking I guess. My buddy dynoed slightly higher like 248, then he removed his cutout and went up to 259. That really impressed me, 11hp with just a cutout. Im installing my cutout this weekend.

We were also abel to do wideband O2 by drilling a hole in the exaust and mounting a fitting for the sensor (then plugging it after). and I was running way rich at the higher rpms. He said there was 20 hp there easy. So Im going to get a DIY tuner guy I know to go down there and rent the dyno and see if we can come up with 20HP.

So let's see, thats 31 more HP for about $300. If that works out thats pretty good bang for the buck. I should be running in the high 12s then I would expect.

i guess elevation and such just rape us up here.....our drag strip is in the middle of a mountain

elevation will do it!
bring it up to pittsburgh raceway and run mid high 13's on slicks.

Whaaat? LS1's run high 12's low 13's with a good driver. LT1's mid-high 13's. Must be where u live.

i am at 5k feet and the ls1 cars run on average 14.2-14.5 and a friend of mine has an 01 firehawk that ran a 13.5 on a fluke run with nittos and an airlid. Lt1 cars are high 14s and the l98 cars are running 14.8-15.3 on average.

AWESOME.....finally someone who has the same track times as me....i was feeling stupid.....thought maybe just no one could drive here hahah

I have gone 13.9 at 97 mph at 2710 feet above sea level with 224 RWHP and 385 RWTQ with a 2.1 60 that was befor the 4 inch mufflex going to see how much faster she is tonight.

Nice times.

Heres my best time

Best time (04/14/06): 60 foot 1.746, 1/8 8.498 at 79.09 mph, 1/4 13.449 at 101.86 mph

239 Horsepower, 315 Torque, and 13.5 air fuel ratio (AFR)



I still need better racing rims and I think i can hit 12s.

holy crap, thats nice ET's for such a low powered motor!

stephen was giving my beast with its new motor thats somewhere in the 300rwhp/350rw ft/lb range about mid 13s!

so good...im not the only one who is amazed that theyre running low 13's with less than 300 horse power.....like i said i need to come where you guys are!!

Was looking around the board ans saw this thread and since I am Larry Dunlap's big rivalery competitin here in hou, I thought I would post.

Both Larry's car and mine have always run within a tenth of each other.

Currently i do not know car weight. My car dynoed on the same Dyno --same day at 259 best run--air filters removed and cut out open--in street trim it was around 240

bottom end stock--bal
ZZ-9 cam--stock L98 iron head port/polished cced
Miniram intake
Hooker shorties
MSD
Stock Torque Convertor + 700 just rebuilt ( 3000 just installed--no strip passes since installed--all times on old TC)
Custom tuned chip---AFR readout looked pretty good all the way across and especially good from 4500 to 5900
4:10 gears
Spohn torque arm
solid trailing arms/pnhard bar
relocation brackets
Nittos (Larry's cast offs--LOL)

Times about the same as Larry

1/8 consistant 8.4's
1/4 mile times--13.3 in cool weather---13.4/13.5 in warmer weather
60'--consistant 1.8's a few 1.79's

So, where do I rank in running what I should be running/running slow/ or what should be expected?

I made 252 rwhp before I exchanged my flowmaster for borla, added 1.6 roller rockers, and got a custom tuned chip. Before was 13.67@ 100.8, after was 13.63 @ 102.8 gained exactly 2 mph. I think I can get it better with some better launching techniques.

Thought I'd chime in since I have some similar data.

First off, most 3rd gens don't show impressive dyno times unless really heavily mod'd or the dyno is an overly generous dynojet.

Don't bother comparing #'s to an LS1, because they are dyno queens, but when they get to the track, as you can see from PHAT89TA, they net a high mph, but can't grab and are usually around low 13's until they get the suspension/tires worked out.

As for my car, fully loaded heavy auto gta, tons of bolt ons, ran 14.1's and had a dyno on a mustang dyno (10% lower than dynojet) of 200@wheels.

With a mild cam and nice heads i've pulled a 13.5@101.8 so far, tpi on top still.
Pretty sure if I dyno again it would be in the 250's.
Doesn't look great on paper, but if you can translate it to the track and hook/launch like Larry and the others, you're at least maximizing your cars potential, which is more than a lot of LS1's do, that have much more power.

Sounds spot on to me - your just effecient!
Using corral HP calculator with vehical weight of 3450 it estimates
FWHP at 303, remove 20% drivetrain loss and leaves you with 242
or so.. Ideal et for 102 trap speed is 13.2, so you are beating ideal et by being effecient.. I would think a th350 and stock 10 bolt would be about 20% on loss. Good job!
Both my cars usually beat ideal et by about 1/10th.

A friend with mustang, bolt on only w/ weight reduction run 12.87 @ 102.8 dynoed at 240 at the wheels.. or so.. 5 speed car, 1.72 60s.

He now dynoed 336 modded, stock bottom and went 11.3 @ 117

Also have seen A couple bone stock LS1 break 12s already - an auto still with stock street tires hit 12.94 with exhaust and pulleys only.

LS1 6 speed cars suffer from a very tall first gear..
2.67 I think - horrible.. but a good clutch slipper can keep that in the power real well, just hard on clutch..

Does anyone have any input on a 305 motor with boltons? Don't ask why I built the 305 up but I have a 383 waiting for me, I just wanted to drive my car this summer. I haven't been the track yet but have been told by a few ppl around here that it's a 13 second car. Probably high 13's but still. Could you guys look at my combo and see what you think?

LB9 TPI
Ported 081 heads - ports/bowl
matched TPI base - stock runners - ported plenum
stock 48mm TB w/Air foil - home made cold air intake
L98 injectors
AFPR - set to 45/47psi
1.6 rockers
LT1 cam (w/1.6 its .477/.489)
700r4 transgo shift kit, 2400 converter
full exhaust (headers, 3" cat, bullet single exit)
3.23 posi - stock rear

Tires are just BFG kdw's, stock size.

Hey just came across the thread today, figures cause the first time I have raced at the track was yesterday. I have a 87 Iroc Z28 with the L98 and a borg warner 9 bolt with the 3.27's. All it has done to it is a set of headers. I ran a 14.662 at 97.23 mph and was wondering if that sounds right or if I was having any issues. My reaction time was .283.

It's a TPI car so just like every other modded TPI car out there it's gonna have a really good 60 foot time with a boat load of torque and a low trap speed with a mediocre horse power number. That's just the way TPI works. The only thing to do is make sure and pick a cam that is good in the lower and mid range and some good heads with similiar flow charecteristics to the vortecs and get some really sticky tires. Or get a new intake like the stealth and run a slower e.t. with a much higher trap speed, lol.

The ability for a car to run a certain time is really dependant on it's torque, stall, gear ratios, and shift points. Also a loose converter will lie to you on the dyno. I've seen dyno graphs of the turbo Chrysler vans that posted insane torque numbers before the converter stalled in then really low hp numbers, the dyno doesn't really tell you what your car will do it just gives you an indication of what it's capable of. The local track I go to has an elevation of 900 feet, at that track LS1's are usually in the mid to low 13 range, LT1's are usually at the low 14 high 13 barrier (stock and mild bolt on cars).

With a 97 MPH trap speed it's capable of more. People usually run 14.6's at like 95 MPH with L98's.

yep i have done 13.89 at 97mph on street tires with headers/exhaust/2800 stall L98 as my only mods. that was with 2.77 gears

OUCH all that money under the hood. They guy I bought the car from I have now ran 13.6 @105 at ennis he never had it on the 1/8. Its basically stock.
91 marrow with 5.7 msd wires, coil, cap, rotor, ngk plugs, lt4 cam (not the hot cam) 3 inch pipes all the way through and through into a flowmaster 80 series eibach pro springs he had ss rims and 275/40/17 eagles i think what ever stock tires are. 4th gen rear gear unknown and a slipping 700r he said every time out of the hole he had wheel hop like crazy he then put spohn relocation brackets and asjustable lca's and a t56 tranny in it. When I bought it he wanted to keep the rims and the rear end so it now has 97 firebird rims and a stock 92 marrow rear.

I'm not sure what it runs now, because the comp needs to be tuned for the cam. I'm not going to tune it till I get my 500 hooker super comp headers on it and replace the msd wires since a few have touched the manifolds :-(. I've been toying with desktop dyno trying to get it at stock readings then toss on the power adders sad thing is dd doesn't have things like wires ignition ect. :-(

I went 13.00 @102 with slicks and no rear seat on 243 rwhp/ 343 rwtq

Good times!! I am hoping for about 13.00 with the removal of cats and installation of cutout and cool weather. I'll have to wait a while for cool weather around here.

heres a pic of my timeslip from the 13.00 run...Don't mind the R/T

I wouldn't go too crazy over a 'exact' number on the dyno. Different brands, different locations, and different times of the year will affect the results. The Dyno computers try to correct for this, but its not a exact science.

The most important function of a dyno is finding 'changes'. X part makes 15 more horsepower than Y part. You find your best combination of parts.

As a side note, I have heard the Mustang dynos output slightly lower results than a Dynojet does.